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Sample records for eurasian perch perca

  1. Domestication drive the changes of immune and digestive system of Eurasian perch (Perca fluviatilis).

    Science.gov (United States)

    Chen, Xiaowen; Wang, Jun; Qian, Long; Gaughan, Sarah; Xiang, Wei; Ai, Tao; Fan, Zhenming; Wang, Chenghui

    2017-01-01

    Domestication has altered a variety of traits within the Eurasian perch (Perca fluviatilis), including phenotypic, physiological and behavioral traits of Eurasian perch (Perca fluviatilis). Little is known, however, about the genetic changes between domesticated and wild Eurasian perch. In this study, we assembled a high-quality de novo reference transcriptome and identified differentially expressed genes between wild and domesticated Eurasian perch. A total of 113,709 transcripts were assembled, and 58,380 transcripts were annotated. Transcriptomic comparison revealed 630 differentially expressed genes between domesticated and wild Eurasian perch. Within domesticated Eurasian perch there were 412 genes that were up-regulated including MHCI, MHCII, chia, ighm within immune system development. There were 218 genes including try1, ctrl, ctrb, cela3b, cpa1 and cpb1, which were down-regulated that were associated with digestive processes. Our results indicated domestication drives the changes of immune and digestive system of Eurasian perch. Our study not only provide valuable genetic resources for further studies in Eurasian perch, but also provide novel insights into the genetic basis of physiological changes in Eurasian perch during domestication process.

  2. The energy requirements of Eurasian perch (Perca fluviatilis L.) in intensive culture

    DEFF Research Database (Denmark)

    Strand, A.; Overton, Julia Lynne; Alanara, A.

    2011-01-01

    requirements of this species. The aim of this study was to develop an energy requirement model for intensive culture of Eurasian perch reared at rational temperatures. Data on growth (the thermal unit growth coefficient, TGC, 3√g ‧ (℃ ‧ days)-1) and digestible energy need (DEN, kJ DE ‧ g -1) of Eurasian perch......Fish feed constitutes one of the largest costs in aquaculture, therefore inefficient feed management will have a negative impact on fish farm economics. Eurasian perch (Perca fluviatilis L.) is a relatively new candidate for freshwater aquaculture, however little is known about the energy...... of the daily theoretical weight increment (TWi, g ‧ day)1) and (ii) a linear DEN model. The TGC model was validated by comparing theoretical data with data obtained from a commercial growth trial. By combining the TWi and the DEN, a model describing the daily theoretical energy requirement (TER, kJ ‧ day)1...

  3. The effect of turbidity and prey fish density on consumption rates of piscivorous Eurasian perch Perca fluviatilis

    DEFF Research Database (Denmark)

    Jacobsen, Lene; Berg, Søren; Baktoft, Henrik

    2014-01-01

    piscivorous Eurasian perch Perca fluviatilis L. This was done in outdoor mesocosm (16 m2) experiments with clear water and two levels of turbidity (25 and 105 NTU) and two prey fish densities [3.1 and 12.5 roach Rutilus rutilus (L.) individuals m–2]. Perch consumption rates were affected by visibility less...... than expected, while they were highly affected by increased prey fish density. Perch responded to high prey density in all visibility conditions, indicating that prey density is more crucial for consumption than visibility in turbid lakes...

  4. Genetic characterization and relatedness of wild and farmed Eurasian perch (Perca fluviatilis: Possible implications for aquaculture practices

    Directory of Open Access Journals (Sweden)

    Sana Ben Khadher

    2016-05-01

    Full Text Available Aquaculture of the Eurasian perch, Perca fluviatilis, in recirculating systems has emerged over the past decades to become a significant way of diversification for inland areas in Europe. The development of such a production relies partly on the improvement of growth performance (i.e., reducing production costs, which requires suitable genetic management of broodstocks and the development of selective breeding programs. In this context, the present study was undertaken assessing for the first time the genetic diversity of farmed stocks of perch. Twelve microsatellite loci were used to investigate the genetic diversity of nine farmed stocks (547 individuals from two perch farms located in France and their supposedly wild founder population from Lake Geneva (394 individuals. First, the wild population displayed the lowest genetic diversity and differed genetically from all farmed populations except one, XB2. Second, genetic diversity did not decrease between farmed breeders and their potential offspring. However, in the three groups of broodstock-offspring the number of alleles decreased by 10%, 21%, and 15%, respectively. In addition, effective population size decreased in all offspring groups. A family structuring was also observed among broodstocks and their offspring, with an unequal family contribution being suspected. In the absence of parental information, these results attest to the utility of genetic tools to evaluate genetic diversity and the necessity of a monitoring program to maintain genetic variability among farmed perch. Genetic variability among farmed stocks appears to be sufficient for perch production to be sustainable and selective breeding programs to be developed.

  5. Decrease of Population Divergence in Eurasian Perch (Perca fluviatilis) in Browning Waters: Role of Fatty Acids and Foraging Efficiency.

    Science.gov (United States)

    Scharnweber, Kristin; Strandberg, Ursula; Karlsson, Konrad; Eklöv, Peter

    2016-01-01

    Due to altered biogeochemical processes related to climate change, highly colored dissolved organic carbon (DOC) from terrestrial sources will lead to a water "brownification" in many freshwater systems of the Northern Hemisphere. This will create deteriorated visual conditions that have been found to affect habitat-specific morphological variations in Eurasian perch (Perca fluviatilis) in a previous study. So far, potential drivers and ultimate causes of these findings have not been identified. We conducted a field study to investigate the connection between morphological divergence and polyunsaturated fatty acid (PUFA) composition of perch from six lakes across a gradient of DOC concentration. We expected a decrease in the prevalence of PUFAs, which are important for perch growth and divergence with increasing DOC concentrations, due to the restructuring effects of DOC on aquatic food webs. In general, rate of morphological divergence in perch decreased with increasing DOC concentrations. Proportions of specific PUFAs (22:6n-3, 18:3n-3, 20:5n-3, and 20:4n-6) identified to primarily contribute to overall differences between perch caught in clear and brown-water lakes tended to be connected to overall decline of morphological divergence. However, no overall significant relationship was found, indicating no severe limitation of essential fatty acids for perch inhabiting brown water lakes. We further broaden our approach by conducting a laboratory experiment on foraging efficiency of perch. Therefore, we induced pelagic and littoral phenotypes by differences in habitat-structure and feeding mode and recorded attack rate in a feeding experiment. Generally, fish were less efficient in foraging on littoral prey (Ephemeroptera) when visual conditions were degraded by brown water color. We concluded that browning water may have a strong effect on the forager's ability to find particular food resources, resulting in the reduced development of evolutionary traits, such as

  6. Spermatozoa motility and variation in the seminal plasma proteome of Eurasian perch (Perca fluviatilis) during the reproductive season.

    Science.gov (United States)

    Shaliutina, A; Hulak, M; Dzuyba, B; Linhart, O

    2012-12-01

    This study evaluated physiological and functional sperm parameters and the seminal plasma proteome of Eurasian perch (Perca fluviatilis) over the course of their reproductive season. Spermatozoa velocity (169.56 ± 6.53 to 158.5 ± 7.4 µm sec(-1)), percent motility (95.89 ± 4.28% to 89.55 ± 4.5%), and osmolality of seminal plasma (290 ± 5 to 297 ± 12 mOsmol kg(-1)) remained stable throughout the reproductive season. Milt volume and protein concentration of seminal plasma gradually increased and reached the highest values late in the reproductive period. Spermatozoa concentration peaked in the mid-reproductive season (66.90 ± 13 × 10(9)  spermatozoa ml(-1)) and decreased towards the end (54 ± 10 × 10(9)  spermatozoa ml(-1)). A proteomic analysis of seminal plasma using two-dimensional polyacrylamide gel electrophoresis revealed 10 protein spots significantly altered over the course of the reproductive season. Subsequent protein characterization suggested that time in the reproductive season predominantly affected proteins involved in membrane trafficking, organization, cell motility, and oxido-reductase activity. This study provides new data on physiological properties of sperm and protein patterns of seminal plasma over the course of the reproductive season that should be considered in the development of methods for artificial reproduction of perch. Copyright © 2012 Wiley Periodicals, Inc.

  7. Salinity tolerance of cultured Eurasian perch, Perca fluviatilis L.: Effects on growth and on survival as a function of temperature

    DEFF Research Database (Denmark)

    Overton, Julia Lynne; Bayley, M.; Paulsen, Helge

    2008-01-01

    Eurasian perch is generally only considered to be a candidate for freshwater aquaculture even though wild populations are found in estuarine and brackish water habitats. Little knowledge exists on two issues a) the effect of temperature on the salinity tolerance of perch and b) the long......-term effects of brackish water on their overall growth performance. The present study addresses these two questions. Firstly, the effect of temperature (12, 15, 20 and 25°C) on perch survival of a salinity challenge at either 13 or 18‰ was determined. Survival was unaffected by 13‰ at the two lowest...... temperatures whereas higher temperature and higher salinities had a dramatic detrimental effect (at 25°C, 50% mortality was reach at 62h and 39h for 13‰ and 18‰, respectively). Secondly, we examined the effect of salinity on growth, which was assessed by measuring standard length and body weight at regular...

  8. Observations of Eurasian perch (Perca fluviatilis L. post-larvae growth performances reared in an illuminated floating cage in Varese lake (N-W Italy over a two years period

    Directory of Open Access Journals (Sweden)

    Micaela Antonini

    2010-02-01

    Full Text Available Eurasian perch (P. fluviatilis is a very important fish species in Varese lake (N-W Italy. Since the second half of 20th century, perch catches in the lake have steadily decreased and by the end of the ‘80s the species resulted clearly endangered. The purpose of this study was to investigate growth, mortality and feeding conditions of perch postlarvae, reared in illuminated floating cage in Varese lake, to obtain fingerlings for a restocking program. In June 2006 and 2007, groups of 280 and 300 pre-weaned post-larvae (average body weight 0.64±0.09 g and 0.25±0.08 g respectively P<0.01 were held in an illuminated net cage for 90 days. The cage was illuminated inside from 20:30 p.m. to 6:30 a.m. During the trial, the nightly zooplankton accumulation inside the cage was assessed weekly. At night time the zooplankton biomass, which resulted dominated by Cladocera family, was higher inside the cage than in the lake. In 2006, 322±36 zooplankters L–1 were observed, compared to 945±600 observed in 2007 (P<0.05. In the lake, the number of zooplankters per litre was similar in both years, resulting in 63.3±50.30 and 61.10±45 zooplankters L–1, respectively on 2006 and 2007. In order to assess perch growth performances, 25 fishes were sampled from the cage every 15-20 days and length (cm and weight (g were assessed for each sample. At the end of September, specific growth rate (SGR and survival rate were assessed. In 2006 the final mean body weight of the perch fry was 4.65±1.47 g and that results significantly lower (P<0.05 than of 2007 (6.3±1.69 g. The SGR was 2.04% and 3.42%, respectively. The higher growth rate observed in 2007 was influenced by a higher zooplankton accumulation in the cage due to an improved cage management. In order to assess the cage efficiency, in September 2006 and 2007, the weight of young-of-year perch (n=50 captured in the lake were compared to those of reared fish. Wild fry showed a mean body weight significantly

  9. Marine spawning sites of perch Perca fluviatilis revealed by oviduct-inserted acoustic transmitters

    DEFF Research Database (Denmark)

    Skovrind, Mikkel; Christensen, Emil A.F.; Carl, Henrik

    2013-01-01

    In the 1970s, a flood-protection system dramatically changed a large part of the coastal environment of Køge Bugt, a bay in the western Baltic Sea, from open coast to a brackish lagoon habitat. An anadromous stock of European perch Perca fluviatilis seems to have benefitted from this change...... a strong proof of concept of oviduct-inserted acoustic transmitters in brackish and marine fish spawning studies. The transmitter expulsions were validated using an egg map, which was based on visual observations of perch egg-strands, and 11 of the 12 expulsed transmitters (92%) were located in areas...... with eggs. Many fish spawned in the brackish water with salinities up to 9.6 PSU. These salinities are higher than those previously observed for European perch spawning in the wild, and call for further investigations of salinity tolerance in perch eggs...

  10. 2,3,7,8-tetrachlorodibenzo-p-dioxin toxicity in yellow perch (Perca flavescens)

    Energy Technology Data Exchange (ETDEWEB)

    Spitsbergen, J.M.; Kleeman, J.M.; Peterson, R.E.

    1988-01-01

    Growth, mortality and morphologic lesions in juvenile, hatchery-reared yellow perch, Perca flavescens, were studied after treatment with graded single doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, 1-125 ..mu..g/kg, intraperitoneally). TCDD doses of 25 and 125 ..mu..g/kg caused 95% mortality by 28 d after treatment, without decreasing body weight. A TCDD dose of 5 ..mu..g/kg resulted in progressive loss of body weight with cumulative mortality of 80% by 80 d posttreatment. Periodic handling stress did not affect the time course of mortality or cumulative percent lethality in TCDD-treated perch. Fin necrosis, petechial cutaneous hemorrhage, and ascites occurred in perch treated with 5 ..mu..g/kg or more of TCDD. Thymic atrophy, decreased hematopoiesis in the head kidney, fibrinous pericarditis, focal myocardial necrosis, submucosal gastric edema, and hyperplasia of the epithelium of gill filaments and lamellae occurred in perch dosed with 25 or 125 ..mu..g/kg. Dose-related splenic lymphoid depletion occurred in perch receiving 5 ..mu..g/kg or more TCDD, and hepatocycte lipidosis occurred in groups treated with doses of 1 ..mu..g/kg or more TCDD. Thus yellow perch are as responsive to the acute toxic effects of TCDD as some of the more sensitive mammalian species, and neither loss of body weight nor histologic lesions in TCDD-treated perch are sufficient to explain mortality.

  11. Evidence of hypoxic foraging forays by yellow perch (Perca flavescens) and potential consequences for prey consumption

    Science.gov (United States)

    Roberts, James J.; Grecay, Paul A.; Ludsin, Stuart A.; Pothoven, Steve A.; Vanderploeg, Henry A.; Höök, Tomas O.

    2012-01-01

    Previous studies in a variety of ecosystems have shown that ecologically and economically important benthic and bentho-pelagic fishes avoid hypoxic (−1) habitats by moving vertically or horizontally to more oxygenated areas. While avoidance of hypoxic conditions generally leads to a complete shift away from preferred benthic prey, some individual fish continue to consume benthic prey items in spite of bottom hypoxia, suggesting complex habitat utilisation and foraging patterns. For example, Lake Erie yellow perch (Perca flavescens) continue to consume benthic prey, despite being displaced vertically and horizontally by hypolimnetic hypoxia. We hypothesised that hypolimnetic hypoxia can negatively affect yellow perch by altering their distribution and inducing energetically expensive foraging behaviour. To test this hypothesis, we used drifting hydroacoustics and trawl sampling to quantify water column distribution, sub-daily vertical movement and foraging behaviour of yellow perch within hypoxic and normoxic habitats of Lake Erie’s central basin during August-September 2007. We also investigated the effects of rapid changes in ambient oxygen conditions on yellow perch consumption potential by exposing yellow perch to various static and fluctuating oxygen conditions in a controlled laboratory experiment. Our results indicate that, while yellow perch in general avoid hypoxic conditions, some individuals undertake foraging forays into hypoxic habitats where they experience greater fluctuations in abiotic conditions (pressure, temperature and oxygen concentration) than at normoxic sites. However, laboratory results suggest short-term exposure to low oxygen conditions did not negatively impact consumption potential of yellow perch. Detailed understanding of sub-daily individual behaviours may be crucial for determining interactive individual- and ecosystem-level effects of stressors such as hypoxia.

  12. Personalities in a crowd: What shapes the behaviour of Eurasian perch and other shoaling fishes?

    Directory of Open Access Journals (Sweden)

    Carin MAGNHAGEN

    2012-02-01

    Full Text Available Lately, there has been an increasing interest in intraspecific variation in behaviour, and numerous studies on persona- lity have been performed in a variety of animals, including several fish species. Individuals have been divided into coping style categories or arranged along a behaviour gradient, such as the bold/shy continuum. However, many fish species live in groups, and the social environment can influence the behaviour of an animal in different ways. There may be conflicts within groups due to competition for resources, and dominance hierarchies are commonly found. On the other hand, there are many benefits of consensus decision-making within the group. Conformity of behaviour is probably adaptive, due to the benefit of public information on, for example, food resources and predation risk. Accordingly, studies of fish shoals have found evidence of consensus decision-making. Furthermore, factors in the environment, such as predation risk would also influence the behaviour expressed. To be able to understand behaviour patterns in a group of fish, it is necessary to consider the variation of individual characteristics, and how the group, as well as other environmental factors, affects the behaviour of individuals. Here, I will review studies on different aspects of personality within a social context in fish, with a special emphasis on the Eurasian perch Perca fluviatilis [Current Zoology 58 (1: 35–44, 2012].

  13. Diphyllobothrium latum in Italy: plerocercoids larvae distribution in perch (Perca fluviatilis fillets

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    MariaLetizia Fioravanti

    2013-04-01

    Full Text Available Following the diffusion of new eating habits (consumption of uncooked, undercooked, marinated or cold-smoked fish, some cases of parasitic zoonosis from freshwater fish are recently reappeared in Italy. One of these is tapeworm Diphyllobothrium latum, whose final host could be human. This study aimed to individuate the position of plerocercoid larvae inside perch fillets (Perca fluviatilis caught in 4 different sites on Como lake in 2011. The fish analyzed were 390. The larvae totally isolated from 112 positive fishes were 164: 85 found in the right fillets and 79 in left ones. According to dorso-ventral disposition in fish, 144 larvae were individuated in dorsal muscles and 20 in ventral ones. Data collected confirm that plerocercoid larvae prefer the upper mass of perch muscle. Dietary education and sanitary care on fish supply are necessary to prevent the diffusion of tapeworm zoonosis in high-risk zones. European legislation establishes freezing to sanitize fish to be eaten raw, marinated or cold-smoked.

  14. Influence of nearshore structure on growth and diets of yellow perch (Perca flavescens) and white perch (Morone americana) in Mexico Bay, Lake Ontario

    Science.gov (United States)

    Danehy, Robert J.; Ringler, Neil H.; Gannon, John E.

    1991-01-01

    The growth diets of 969 yellow perch (Perca flavescens) and white perch (Morone americana) caught at 3.3 and 7.0 m depths were compared between two cobble/rubble shoals and two featureless sand sites in Mexico Bay, eastern Lake Ontario during 1981. The growth rate of both species was significantly greater for individuals captured over the cobble/rubble shoals. Females of both species were faster growing than the males, although only significantly so in the white perch. The seasonal diet and breadth of diet (H′) of yellow perch and white perch were not substantially different with respect to substrate type. Diet overlap between substrate types was also equivalent for each species. Benthic invertebrates, primarilyGammarus spp., were the major prey of both species at all sites. Alewife eggs were the most important item for the white perch in mid-summer, and alewife juveniles were important to both species in the fall. Differences in growth patterns between cobble/rubble shoals and sand sites illustrate a subtle effect of habitat on these species.

  15. Histopathology and the inflammatory response of European perch, Perca fluviatilis muscle infected with Eustrongylides sp. (Nematoda).

    Science.gov (United States)

    Dezfuli, Bahram S; Manera, Maurizio; Lorenzoni, Massimo; Pironi, Flavio; Shinn, Andrew P; Giari, Luisa

    2015-04-15

    The European perch, Perca fluviatilis L. is a common paratenic host of dioctophymatid nematodes belonging to the genus Eustrongylides. In this host, once infected oligochaetes, which serve as the first intermediate host, are ingested, Eustrongylides migrates through the intestine and is frequently encountered within the musculature, free within the body cavity, or encapsulated on the viscera. The current study details the first Italian record of Eustrongylides sp. with larvae reported in the muscle of P. fluviatilis. Uninfected and nematode-infected muscle tissues of perch were fixed and prepared for histological evaluation and electron microscopy. Some sections were subjected to an indirect immunohistochemical method using anti-PCNA, anti-piscidin 3 and anti-piscidin 4 antibodies. A total of 510 P. fluviatilis (TL range 15-25 cm) from Lake Trasimeno, Perugia were post-mortemed; 31 individuals had encysted nematode larvae within their musculature (1-2 worms fish(-1)). Histologically, larvae were surrounded by a capsule with an evident acute inflammatory reaction. Muscle degeneration and necrosis extending throughout the sarcoplasm, sarcolemmal basal lamina, endomysial connective tissue cells and capillaries was frequently observed. Within the encapsulating reaction, macrophage aggregates (MAs) were seen. Immunohistochemical staining with the proliferating cell nuclear antigen (PCNA) revealed numerous PCNA-positive cells within the thickness of the capsule and in the immediate vicinity surrounding Eustrongylides sp. larvae (i.e. fibroblasts and satellite cells), suggesting a host response had been initiated to repair the nematode-damaged muscle. Mast cells (MCs) staining positively for piscidin 3, were demonstrated for the first time in response to a muscle-infecting nematode. The piscidin 3 positive MC's were seen principally in the periphery of the capsule surrounding the Eustrongylides sp. larva. A host tissue response to Eustrongylides sp. larvae infecting the

  16. Flow cytometric method for measuring chromatin fragmentation in fixed sperm from yellow perch (Perca flavescens)

    Science.gov (United States)

    Jenkins, Jill A.; Draugelis-Dale, Rassa O.; Pinkney, Alfred E.; Iwanowicz, Luke R.; Blazer, Vicki

    2015-01-01

    Declining harvests of yellow perch, Perca flavescens, in urbanized watersheds of Chesapeake Bay have prompted investigations of their reproductive fitness. The purpose of this study was to establish a flow cytometric technique for DNA analysis of fixed samples sent from the field to provide reliable gamete quality measurements. Similar to the sperm chromatin structure assay, measures were made on the susceptibility of nuclear DNA to acid-induced denaturation, but used fixed rather than live or thawed cells. Nuclei were best exposed to the acid treatment for 1 minute at 37 °C followed by the addition of cold (4 °C) propidium iodide staining solution before flow cytometry. The rationale for protocol development is presented graphically through cytograms. Field results collected in 2008 and 2009 revealed DNA fragmentation up to 14.5%. In 2008, DNA fragmentation from the more urbanized watersheds was significantly greater than from reference sites (P = 0.026) and in 2009, higher percentages of haploid testicular cells were noted from the less urbanized watersheds (P = 0.032) indicating better reproductive condition at sites with less urbanization. For both years, total and progressive live sperm motilities by computer-assisted sperm motion analysis ranged from 19.1% to 76.5%, being significantly higher at the less urbanized sites (P < 0.05). This flow cytometric method takes advantage of the propensity of fragmented DNA to be denatured under standard conditions, or 1 minute at 37 °C with 10% buffered formalin–fixed cells. The study of fixed sperm makes possible the restrospective investigation of germplasm fragmentation, spermatogenic ploidy patterns, and chromatin compaction levels from samples translocated over distance and time. The protocol provides an approach that can be modified for other species across taxa.

  17. Establishment and interspecific associations in two species of Ichthyocotylurus (Trematoda) parasites in perch (Perca fluviatilis)

    Science.gov (United States)

    2011-01-01

    Background Co-infections of multiple parasite species in hosts may lead to interspecific associations and subsequently shape the structure of a parasite community. However, few studies have focused on these associations in highly abundant parasite species or, in particular, investigated how the associations develop with time in hosts exposed to co-infecting parasite species for the first time. We investigated metacercarial establishment and interspecific associations in the trematodes Ichthyocotylurus variegatus and I. pileatus co-infecting three age cohorts of young perch (Perca fluviatilis). Results We found that the timing of transmission of the two Ichthyocotylurus species was very similar, but they showed differences in metacercarial development essentially so that the metacercariae of I. pileatus became encapsulated faster. Correlations between the abundances of the species were significantly positive after the first summer of host life and also within the main site of infection, the swim bladder. High or low abundances of both parasite species were also more frequent in the same host individuals than expected by chance, independently of host age or size. However, the highest abundances of the species were nevertheless observed in different host individuals and this pattern was consistent in all age cohorts. Conclusions The results suggest similar temporal patterns of transmission, non-random establishment, and facilitative rather than competitive associations between the parasite species independently of the age of the infracommunities. However, we suggest that spatial differences in exposure are most likely responsible for the segregation of the parasite species observed in the few most heavily infected hosts. Regardless of the underlying mechanism, the result suggests that between-species associations should be interpreted with caution along with detailed examination of the parasite distribution among host individuals. PMID:21599910

  18. REPRODUCTIVE PHYSIOLOGY OF YELLOW PERCH (PERCA FLAVESCENS): ENVIRONMENTAL AND ENDOCRINOLOGICAL CUES

    Science.gov (United States)

    An understanding of the mechanisms involved in the regulation of reproductive processes in yellow perch is fundamental for intensive culture of this commercially important, freshwater, perciform fish. This paper describes the annual reproductive cycle of female and male perch. It...

  19. Reproductive health of yellow perch Perca flavescens in selected tributaries of the Chesapeake Bay

    Science.gov (United States)

    Blazer, Vicki; Pinkney, Alfred E.; Jenkins, Jill A.; Iwanowicz, Luke R.; Minkkinen, Steven; Draugelis-Dale, Rassa O.; Uphoff, James H.

    2013-01-01

    Reduced recruitment of yellow perch has been noted for a number of years in certain urbanized watersheds (South and Severn Rivers) of the Chesapeake Bay. Other rapidly developing watersheds such as Mattawoman Creek are more recently showing evidence of reduced recruitment of anadromous fishes. In this study, we used a battery of biomarkers to better document the reproductive health of adult yellow perch collected during spring spawning in 2007–2009. Perch were collected in the South and Severn Rivers, Mattawoman Creek and the less developed Choptank and Allen's Fresh watersheds for comparison. Gonadosomatic indices, plasma reproductive hormone concentrations, plasma vitellogenin concentrations and gonad histology were evaluated in mature perch of both sexes. In addition, sperm quantity (cell counts) and quality (total and progressive motility, spermatogenic stage and DNA integrity), were measured in male perch. Many of these biomarkers varied annually and spatially, with some interesting statistical results and trends. Male perch from the Choptank and Allen's Fresh had generally higher sperm counts. In 2008 counts were significantly lower in the perch from the Severn when compared to other sites. The major microscopic gonadal abnormality in males was the proliferation of putative Leydig cells, observed in testes from Severn and less commonly, Mattawoman Creek perch. Observations that could significantly impact egg viability were an apparent lack of final maturation, abnormal yolk and thin, irregular zona pellucida. These were observed primarily in ovaries from Severn, South and less commonly Mattawoman Creek perch. The potential association of these observations with urbanization, impervious surface and chemical contaminants is discussed.

  20. Reproductive health of yellow perch Perca flavescens in selected tributaries of the Chesapeake Bay

    Energy Technology Data Exchange (ETDEWEB)

    Blazer, Vicki S., E-mail: Vblazer@usgs.gov [U.S. Geological Survey, National Fish Health Research Laboratory, Leetown Science Center, 11649 Leetown Road, Kearneysville, WV 25430 (United States); Pinkney, Alfred E., E-mail: Fred_Pinkeny@fws.gov [U.S. Fish and Wildlife Service, Chesapeake Bay Field Office, 177 Admiral Cochrane Drive, Annapolis, MD 21401 (United States); Jenkins, Jill A., E-mail: jenkinsj@usgs.gov [U.S. Geological Survey, National Wetlands Research Center, 700 Cajundome Blvd., Lafayette, LA 70506 (United States); Iwanowicz, Luke R., E-mail: Liwanowicz@usgs.gov [U.S. Geological Survey, National Fish Health Research Laboratory, Leetown Science Center, 11649 Leetown Road, Kearneysville, WV 25430 (United States); Minkkinen, Steven, E-mail: steve_minkkinen@fws.gov [U.S. Fish and Wildlife Service, Chesapeake Bay Field Office, 177 Admiral Cochrane Drive, Annapolis, MD 21401 (United States); Draugelis-Dale, Rassa O., E-mail: daler@usgs.gov [U.S. Geological Survey, National Wetlands Research Center, 700 Cajundome Blvd., Lafayette, LA 70506 (United States); Uphoff, James H., E-mail: juphoff@dnr.state.md.us [Maryland Department of Natural Resources, Fisheries Service, Cooperative Oxford Laboratory, 904 South Morris Street, Oxford, MD 21654 (United States)

    2013-03-01

    Reduced recruitment of yellow perch has been noted for a number of years in certain urbanized watersheds (South and Severn Rivers) of the Chesapeake Bay. Other rapidly developing watersheds such as Mattawoman Creek are more recently showing evidence of reduced recruitment of anadromous fishes. In this study, we used a battery of biomarkers to better document the reproductive health of adult yellow perch collected during spring spawning in 2007–2009. Perch were collected in the South and Severn Rivers, Mattawoman Creek and the less developed Choptank and Allen's Fresh watersheds for comparison. Gonadosomatic indices, plasma reproductive hormone concentrations, plasma vitellogenin concentrations and gonad histology were evaluated in mature perch of both sexes. In addition, sperm quantity (cell counts) and quality (total and progressive motility, spermatogenic stage and DNA integrity), were measured in male perch. Many of these biomarkers varied annually and spatially, with some interesting statistical results and trends. Male perch from the Choptank and Allen's Fresh had generally higher sperm counts. In 2008 counts were significantly lower in the perch from the Severn when compared to other sites. The major microscopic gonadal abnormality in males was the proliferation of putative Leydig cells, observed in testes from Severn and less commonly, Mattawoman Creek perch. Observations that could significantly impact egg viability were an apparent lack of final maturation, abnormal yolk and thin, irregular zona pellucida. These were observed primarily in ovaries from Severn, South and less commonly Mattawoman Creek perch. The potential association of these observations with urbanization, impervious surface and chemical contaminants is discussed. - Highlights: ► Reduced recruitment of yellow perch has occurred in urban tributaries of Chesapeake Bay. ► We compared reproductive health biomarkers in perch from two urban, one developing, two less developed

  1. Reproductive health of yellow perch, Perca flavescens, in Chesapeake Bay Tributaries

    Science.gov (United States)

    Blazer, Vicki; Pinkney, A.E.; Uphoff, James H.

    2013-01-01

    Yellow perch live in creeks, rivers, ponds, lakes, and estuaries across the central and eastern United States and Canada. In Chesapeake Bay, they tolerate salinities up to one-third that of seawater. The adults reside in the brackish waters of the bay’s tributaries and migrate upstream to spawn. Yellow perch are eagerly sought by recreational fishermen for their excellent taste and, because their late winter spawning runs are the earliest of the year, they are regarded as a harbinger of spring. Yellow perch also support a small but valuable, tightly regulated commercial fishery in the part of Chesapeake Bay that lies in Maryland.

  2. Feeding under predation risk: potential sex-specific response of perch (Perca fluviatilis).

    Czech Academy of Sciences Publication Activity Database

    Estlander, Satu; Nurminen, L.

    2014-01-01

    Roč. 23, č. 3 (2014), s. 478-480 ISSN 0906-6691 Institutional support: RVO:60077344 Keywords : foraging * sexual size dimorphism * predation * perch * pike Subject RIV: EH - Ecology, Behaviour Impact factor: 1.701, year: 2014

  3. Challenge studies of European stocks of redfin perch, Perca fluviatilis L., and rainbow trout, Oncorhynchus mykiss (Walbaum), with epizootic haematopoietic necrosis virus

    DEFF Research Database (Denmark)

    Ariel, Ellen; Jensen, Ann Britt Bang

    2009-01-01

    A challenge model for comparison of the virulence of epizootic haematopoietic necrosis virus (EHNV) to European stock of redfin perch, Perca fluviatilis L., and rainbow trout, Oncorhynchus mykiss (Walbaum), was tested. The model investigated intraperitoneal (IP), bath and cohabitation routes at 10......, 15 and 20 C for 5–6 g fish and 15 C for 20 g perch. In the IP challenges of perch, significant mortality occurred at 15 C and 20 C. In challenge trials for rainbow trout, significant mortalities were observed in IP and bath challenges at 20 C. The mortality observed in IP-challenged 20 g perch...... was not significantly different from that recorded for 6 g fish challenged IP. No significant mortality was observed in any other treatment groups. Re-isolation of ranavirus was confirmed by IFAT and was con- sistently associated with dead or moribund fish in the trial groups challenged with EHNV. The find- ings...

  4. Larval dispersal underlies demographically important inter-system connectivity in a Great Lakes yellow perch (Perca flavescens) population

    Science.gov (United States)

    Brodnik, Reed M.; Fraker, Michael E.; Anderson, Eric J.; Carreon-Martinez, Lucia; DeVanna, Kristen M.; Heath, Dan D.; Reichert, Julie M.; Roseman, Edward F.; Ludsin, Stuart A.

    2016-01-01

    Ability to quantify connectivity among spawning subpopulations and their relative contribution of recruits to the broader population is a critical fisheries management need. By combining microsatellite and age information from larval yellow perch (Perca flavescens) collected in the Lake St. Clair – Detroit River system (SC-DRS) and western Lake Erie with a hydrodynamic backtracking approach, we quantified subpopulation structure, connectivity, and contributions of recruits to the juvenile stage in western Lake Erie during 2006-2007. After finding weak (yet stable) genetic structure between the SC-DRS and two western Lake Erie subpopulations, microsatellites also revealed measurable recruitment of SC-DRS larvae to the juvenile stage in western Lake Erie (17-21% during 2006-2007). Consideration of pre-collection larval dispersal trajectories, using hydrodynamic backtracking, increased estimated contributions to 65% in 2006 and 57% in 2007. Our findings highlight the value of complementing subpopulation discrimination methods with hydrodynamic predictions of larval dispersal by revealing the SC-DRS as a source of recruits to western Lake Erie and also showing that connectivity through larval dispersal can affect the structure and dynamics of large-lake fish populations.

  5. Baseline concentrations of biliary PAH metabolites in perch (Perca fluviatilis) in the open Gulf of Finland and in two coastal areas

    Science.gov (United States)

    Vuorinen, Pekka J.; Saulamo, Kari; Lecklin, Tiina; Rahikainen, Mika; Koivisto, Pertti; Keinänen, Marja

    2017-07-01

    Female perch (Perca fluviatilis) were sampled annually in late summer from 2006 to 2009 from the open sea of the eastern Gulf of Finland off Haapasaari island to monitor baseline biliary PAH metabolite concentrations. In addition, two coastal locations were sampled in 2008. PAH metabolite concentrations were compared between the open sea and coastal samples and between the sampling years and examined in relation to the body characteristics of perch. Of the PAH metabolites, only 1-hydroxypyrene (1-OH pyrene) was detected at quantifiable levels in the bile of nearly all perch individuals. There were some annual differences but no temporal trend in the concentration of biliary 1-OH pyrene in perch from Haapasaari. At the coastal locations, 1-OH pyrene concentrations in the bile of perch were significantly higher than in the open sea Haapasaari area, probably due to greater contamination of the coastal sites and differences in feeding behaviour. No correlations between the body characteristics of perch and 1-OH pyrene concentrations were detected. It is concluded that PAH metabolites in the bile of fish could be measured in the Gulf of Finland to detect oil spills in the open sea, and the cost-effective total fluorescence method could be used in such monitoring programmes.

  6. Yellow Perch (Perca flavescens) Mercury Unaffected by Wildland Fires in Northern Minnesota.

    Science.gov (United States)

    Riggs, Charlotte E; Kolka, Randall K; Nater, Edward A; Witt, Emma L; Wickman, Trent R; Woodruff, Laurel G; Butcher, Jason T

    2017-05-01

    Wildland fire can alter mercury (Hg) cycling on land and in adjacent aquatic environments. In addition to enhancing local atmospheric Hg redeposition, fire can influence terrestrial movement of Hg and other elements into lakes via runoff from burned upland soil. However, the impact of fire on water quality and the accumulation of Hg in fish remain equivocal. We investigated the effects of fire-specifically, a low-severity prescribed fire and moderate-severity wildfire-on young-of-the-year yellow perch () and lake chemistry in a small remote watershed in the Boundary Waters Canoe Area Wilderness in northeastern Minnesota. We used a paired watershed approach: the fire-affected watershed was compared with an adjacent, unimpacted (reference) watershed. Prior to fire, upland organic horizons in the two study watersheds contained 1549 μg Hg m on average. Despite a 19% decrease in upland organic horizon Hg stocks due to the moderate severity wildfire fire, fish Hg accumulation and lake productivity were not affected by fire in subsequent years. Instead, climate and lake water levels were the strongest predictors of lake chemistry and fish responses in our study lakes over 9 yr. Our results suggest that low- to moderate-severity wildland fire does not alter lake productivity or Hg accumulation in young-of-the-year yellow perch in these small, shallow lakes in the northern deciduous and boreal forest region. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  7. Variation of whole body amino acid profile in Eurasian perch Perca ...

    African Journals Online (AJOL)

    Dr Gatsing

    amino acid needs of other fish in order to design and improve their test diets. Wilson and Poe (1985) have reported that the amino acid patterns of fish eggs and whole body tissue have been used for this purpose in channel catfish Ictalurus punctatus. Rumsey and Ketola (1975) reported that improved growth was observed ...

  8. Variation of whole body amino acid profile in Eurasian perch Perca ...

    African Journals Online (AJOL)

    Samples of fish were analyzed on the Water Pico-Tag amino acid analysis system. For the study period, survival rate calculated after counting all survival fish reached 7.5%. Final fish body weight averaged 0.850 ± 0.678 g (measured for 600 fish), but some large fish reached up to 2.1 g. During the first week, specific growth ...

  9. The effect of salinity on resting metabolism in Eurasian perch (Perca fluviathlis L.)

    DEFF Research Database (Denmark)

    Ern, R.; Cong, N.; Houng, D.

    2008-01-01

    to properly maintain ion balance even with minor increases in the environmental salinity. The elevated resting VO2 in 10 ppt is equivalent to an increased energy consumption of 975 extra calories per day, and since food intake was unaffected, it is reasonable to assume that the reduced growth seen...

  10. Location and timing of the deposition of egg strands by perch (Perca fluviatilis L.: the roles of lake hydrology, spawning substrate and female size

    Directory of Open Access Journals (Sweden)

    Čech M.

    2011-10-01

    Full Text Available The reproduction biology of perch Perca fluviatilis was studied in relation to lake hydrology, spawning substrate and female size using SCUBA divers during late April and mid-May 2009 in Chabařovice Lake, Czech Republic. An extreme displacement of water mass, induced by a long-lasting strong wind, caused the abundance of egg strands to differ significantly between individual parts of the lake. On average, 91% of perch spawning activity occurred at depths greater than 3 m. The mean concentration of dissolved organic carbon (DOC indicated that the lake belongs to the category where DOC influencing the penetration of ultraviolet radiation, is not responsible for the deep deposition of egg strands by perch. Most probably, the avoidance of shallow depths (<3 m results from strong wind/waves coming from any direction. Larger perch females started to spawn earlier than their smaller conspecifics and they used shallower depths for depositing their egg strands. As a spawning substrate, perch strongly selected dead submerged vegetation, such as common reed Phragmites communis and worm weed Artemisia sp. These substrates, however, reveal signs of progressive degradation and seem likely to disappear from the lake within several years.

  11. A comparative assessment of the adrenotoxic effects of cadmium in two teleost species, rainbow trout, Oncorhynchus mykiss, and yellow perch, Perca flavescens

    Energy Technology Data Exchange (ETDEWEB)

    Lacroix, Alexandra; Hontela, Alice

    2004-03-30

    Rainbow trout (Oncorhynchus mykiss) and yellow perch (Perca flavescens) have a different sensitivity to cadmium (Cd) in vivo (troutperch). Metals and particularly Cd impair cortisol secretion by adrenocortical cells in both species. The purpose of the present study was to assess in vitro the effect of Cd on cortisol secretion by adrenocortical cells of trout and perch, to compare the sensitivity of adrenal steroidogenesis in these two teleosts. Adrenocortical cells were exposed to Cd for 60 min, then stimulated with ACTH, dbcAMP or with pregnenolone, a cortisol precursor. Cd inhibited ACTH-stimulated cortisol secretion in a dose-dependent manner in both fish species, however, the EC50s (concentration resulting in 50% inhibition of cortisol secretion) was significantly lower in trout (EC50=0.09 mM) than perch (EC50=0.26 mM). To test the specificity of Cd to act as an endocrine disrupter, the LC50 (concentration that kills 50% of the cells) was also evaluated to determine the LC50/EC50 ratio (LC50/EC50{sub O.mykiss}=175.6>LC50/EC50{sub P.flavescens}=37.7). Adrenocortical cells of trout were more sensitive than those of perch and Cd had a higher endocrine-disrupting potential and specificity in trout than in perch. However, in both species, Cd had the same effect on ACTH, dbcAMP and pregnenolone-stimulated cortisol secretion, with pregnenolone maintaining cortisol secretion until cell viability was impaired. These results confirm that for both species, Cd interferes in the signalling pathway of cortisol synthesis in a step prior to the pregnenolone formation. Data provided by the present study revealed important differences in vulnerability of adrenal steroidogenesis between rainbow trout and yellow perch.

  12. Prévalence de l’infestation par Diphyllobothrium latum, L., 1758 chez les perches (Perca fluviatilis du lac Léman

    Directory of Open Access Journals (Sweden)

    Nicoulaud J.

    2005-12-01

    Full Text Available La bothriocéphalose se contracte en consommant des poissons d’eau douce crus ou peu cuits et est encore présente sur les rivages du lac Léman. Le but de cette étude était d’évaluer la prévalence des larves plérocercoïdes de Diphyllobothrium latum dans les perches (Perca fluviatilis de ce lac. Des larves de D. latum ont été retrouvées dans 4 à 10% des filets de perche examinés en novembre 2003, février 2004, avril 2004 et janvier 2005. L’identification des larves a été confirmée par PCR et séquençage de l’ADNr 18S.

  13. Biochemical and ultrastructural changes in the liver of European perch (Perca fluviatilis L. in response to cyanobacterial bloom in the Gruža reservoir

    Directory of Open Access Journals (Sweden)

    Perendija Branka R.

    2011-01-01

    Full Text Available We investigated the biochemical and ultrastructural changes in the liver of the freshwater fish, European perch (Perca fluviatilis, in response to Aphanizomenon flos-aquae bloom in the Gruža Reservoir, Serbia. The activities of total manganese- and copper zinc-containing superoxide dismutase (Tot SOD, Mn-SOD, Cu/Zn-SOD, catalase (CAT, glutathione peroxidase (GSH-Px, glutathione reductase (GR and biotransformation phase II enzyme glutathione-S-transferase (GST, as well as concentrations of total glutathione (GSH and sulfhydryl (-SH groups were examined before and during the bloom period. Mn-SOD activity was significantly higher, while the activities of Cu/Zn-SOD, CAT and GSH-Px and the concentration of the -SH groups were significantly lower during the bloom. The ultrastructure of the liver revealed necrotic and apoptotic damage to the hepatocytes during the bloom period. Our work represents the first study to report the influences of an Aphanizomenon flos-aquae bloom in the Gruža Reservoir on antioxidant biomarkers and on histopathological alterations in the liver of the freshwater fish European perch (Perca fluviatilis.

  14. Integrated spatial health assessment of yellow perch (Perca flavescens) populations from the St. Lawrence River (QC, Canada), part B: cellular and transcriptomic effects.

    Science.gov (United States)

    Bruneau, Audrey; Landry, Catherine; Giraudo, Maeva; Douville, Mélanie; Brodeur, Philippe; Boily, Monique; Gagnon, Pierre; Houde, Magali

    2016-09-01

    Multi-biological level assessments have become great tools to evaluate the health of aquatic ecosystems. Using this approach, a complementary study was designed to evaluate the health of yellow perch (Perca flavescens) populations in the St. Lawrence River (Quebec, Canada). In the present study, stress responses were compared at the transcriptomic, cellular, and tissue levels in yellow perch collected at six sites along the river: Lake St. François, Lake St. Louis (north and south), Beauregard Island and Lake St. Pierre (north and south). These results complement the physiological and chemical parameters as well as pathogen infection investigated in a companion paper published in the present issue. Thiobarbituric acid reactive substance (TBARS) analyses indicated the presence of oxidative stress in fish collected in the southern part of Lake St. Louis and at the downstream sites of Lake St. Pierre. High lipid peroxidation levels were found in the muscle of yellow perch caught at Beauregard Island, located downstream of the Montreal's wastewater treatment plant, suggesting an impact of the municipal effluent on redox homeostasis. Transcriptomic results indicated the down-regulation of genes related to lipid, glucose, and retinoid in southern Lake St. Pierre as well as a decrease in retinoid storage. Overall, biochemical and molecular markers indicated that the health status of yellow perch followed a decreasing gradient from upstream to downstream of the St. Lawrence River. This gradient is representative of the cumulative negative impacts of human activities on water and habitat quality along the river.

  15. Branchial cadmium and copper binding and intestinal cadmium uptake in wild yellow perch (Perca flavescens) from clean and metal-contaminated lakes.

    Science.gov (United States)

    Klinck, J S; Green, W W; Mirza, R S; Nadella, S R; Chowdhury, M J; Wood, C M; Pyle, G G

    2007-08-30

    Branchial binding kinetics and gastro-intestinal uptake of copper and cadmium where examined in yellow perch (Perca flavescens) from a metal-contaminated lake (Hannah Lake, Sudbury, Ontario, Canada) and an uncontaminated lake (James Lake, North Bay, Ontario, Canada). An in vivo approach was taken for gill binding comparisons while an in vitro gut binding assay was employed for gastro-intestinal tract (GIT) uptake analysis. By investigating metal uptake at the gill and the gut we cover the two main routes of metal entry into fish. Comparisons of water and sediment chemistries, metal burdens in benthic invertebrate, and metal burdens in the livers of perch from the two study lakes clearly show that yellow perch from Hannah L. are chronically exposed to a highly metal-contaminated environment compared to a reference lake. We found that metal-contaminated yellow perch showed no significant difference in gill Cd binding compared to reference fish, but they did show significant decreases in new Cd binding and absorption in their GITs. The results show that gill Cd binding may involve low-capacity, high-affinity binding sites, while gastro-intestinal Cd uptake involves binding sites that are high-capacity, low-affinity. From this we infer that Cd may be more critically controlled at the gut rather than gills. Significant differences in branchial Cu binding (increased binding) were observed in metal-contaminated yellow perch. We suggest that chronic waterborne exposure to Cu (and/or other metals) may be the dominant influence in gill Cu binding rather than chronic exposure to high Cu diets. We give supporting evidence that Cd is taken up in the GIT, at least in part, by a similar pathway as Ca(2+), principally that elevated dietary Ca(2+) reduces Cd binding and uptake. Overall our study reveals that metal pre-exposure via water and diet can alter uptake kinetics of Cu and Cd at the gill and/or the gut.

  16. Diphyllobothrium latum (Cestoda: Diphyllobothriidea in perch (Perca fluviatilis in three sub-alpine lakes: influence of biotic and abiotic factors on prevalence

    Directory of Open Access Journals (Sweden)

    Orlando PETRINI

    2009-08-01

    Full Text Available In recent years, human diphyllobothriosis has staged a comeback in Swiss, French and Italian sub-alpine regions. The main putative infective source of the causative agent (the tapeworm Diphyllobothrium latum in these areas is perch (Perca fluviatilis. Therefore, the occurrence of D. latum in this fish species was investigated between 2005 and 2008 in the sub-alpine lakes Maggiore, Lugano and Geneva. Prevalence in fish of Lake Maggiore was 14% (n = 880. In Lake Geneva, 5.1% fillets (n = 532 were infected, whereas perch from Lake Lugano were free from the parasite. These results are discussed in relation to previous studies. Data on fish size and weight indicate that infection of perch by D. latum is independent of age and sex. Abiotic factors considered critical for D. latum life cycle (water temperature and oxygen concentration characterize the three basins and were related to their infestation frequencies. The presence of this parasite was most likely favoured by warmer, well oxygenated waters. Previous studies indicate that the lake’s trophic state (i.e. content of total phosphorus influenced the availability of the first intermediate hosts (copepods of some pseudophyllideans. In our study, no correlation was observed between the amount of phosphorus and the number of copepods in populations of zooplankton. Nevertheless, the trophic states of the three lakes seemed to affect the degree of infection in fish. In conclusion, at least in sub-alpine lakes, abiotic factors such as water temperature, oxygenation and trophic state seem to have an influence on maintaining or preventing perch infection with D. latum.

  17. Concentrations of Zn, Mn, Cu and Cd in different tissues of perch (Perca fluviatilis) and in perch intestinal parasite (Acanthocephalus lucii) from the stream near Prague (Czech Republic)

    Energy Technology Data Exchange (ETDEWEB)

    Jankovska, Ivana, E-mail: jankovska@af.czu.cz [Department of Zoology and Fisheries, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, 165 21 Prague 6 - Suchdol (Czech Republic); Miholova, Daniela [Department of Chemistry, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, 165 21 Prague 6 - Suchdol (Czech Republic); Lukesova, Daniela [Department of Animal Science and Food Processing in Tropics and Subtropics, Institute of Tropics and Subtropics, Czech University of Life Sciences, 165 21 Prague 6 - Suchdol (Czech Republic); Kalous, Lukas; Valek, Petr; Romocusky, Stepan; Vadlejch, Jaroslav; Petrtyl, Miloslav; Langrova, Iva; Cadkova, Zuzana [Department of Zoology and Fisheries, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, 165 21 Prague 6 - Suchdol (Czech Republic)

    2012-01-15

    We monitored concentrations of Cd, Cu, Mn and Zn in acantocephalan parasites (Acanthocephalus lucii) and its final host (Perca fluviatilis). The concentrations in parasites were found to be significantly higher than those found in the muscle, gonads and liver of fish host. The bioaccumulation factor values were 194, 24.4, 2.2 and 4.7 for Cd, Cu, Mn and Zn, respectively. This suggests a benefit for the host due to the high accumulation of toxic cadmium.

  18. Expression kinetics of key genes in the early innate immune response to Great Lakes viral hemorrhagic septicemia virus IVb infection in yellow perch (Perca flavescens)

    Science.gov (United States)

    Olson, Wendy; Emmenegger, Eveline; Glenn, Jolene; Simchick, Crystal; Winton, Jim; Goetz, Frederick

    2013-01-01

    The recently discovered strain of viral hemorrhagic septicemia virus, VHSV-IVb, represents an example of the introduction of an extremely pathogenic rhabdovirus capable of infecting a wide variety of new fish species in a new host-environment. The goal of the present study was to delineate the expression kinetics of key genes in the innate immune response relative to the very early stages of VHSV-IVb infection using the yellow perch (Perca flavescens) as a model. Administration of VHSV-IVb by IP-injection into juvenile yellow perch resulted in 84% cumulative mortality, indicating their high susceptibility to this disease. In fish sampled in the very early stages of infection, a significant up-regulation of Mx gene expression in the liver, as well as IL-1β and SAA activation in the head kidney, spleen, and liver was directly correlated to viral load. The potential down-regulation of Mx in the hematopoietic tissues, head kidney and spleen, may represent a strategy utilized by the virus to increase replication.

  19. A Kinetic Study of Accumulation and Elimination of Microcystin-LR in Yellow Perch (Perca Flavescens Tissue and Implications for Human Fish Consumption

    Directory of Open Access Journals (Sweden)

    Donna R. Kashian

    2011-12-01

    Full Text Available Fish consumption is a potential route of human exposure to the hepatotoxic microcystins, especially in lakes and reservoirs that routinely experience significant toxic Microcystis blooms. Understanding the rates of uptake and elimination for microcystins as well as the transfer efficiency into tissues of consumers are important for determining the potential for microcystins to be transferred up the food web and for predicting potential human health impacts. The main objective of this work was to conduct laboratory experiments to investigate the kinetics of toxin accumulation in fish tissue. An oral route of exposure was employed in this study, in which juvenile yellow perch (Perca flavescens were given a single oral dose of 5 or 20 μg of microcystin-LR (MC-LR via food and accumulation in the muscle, liver, and tank water were measured over 24 h. Peak concentrations of the water soluble fraction of microcystin were generally observed 8–10 h after dosing in the liver and after 12–16 h in the muscle, with a rapid decline in both tissues by 24 h. Up to 99% of the total recoverable (i.e., unbound microcystin was measured in the tank water by 16 h after exposure. The relatively rapid uptake and elimination of the unbound fraction of microcystin in the liver and muscle of juvenile yellow perch within 24 h of exposure indicates that fish consumption may not be a major route of human exposure to microcystin, particularly in the Great Lakes.

  20. A kinetic study of accumulation and elimination of microcystin-LR in yellow perch (Perca flavescens) tissue and implications for human fish consumption.

    Science.gov (United States)

    Dyble, Julianne; Gossiaux, Duane; Landrum, Peter; Kashian, Donna R; Pothoven, Steven

    2011-12-01

    Fish consumption is a potential route of human exposure to the hepatotoxic microcystins, especially in lakes and reservoirs that routinely experience significant toxic Microcystis blooms. Understanding the rates of uptake and elimination for microcystins as well as the transfer efficiency into tissues of consumers are important for determining the potential for microcystins to be transferred up the food web and for predicting potential human health impacts. The main objective of this work was to conduct laboratory experiments to investigate the kinetics of toxin accumulation in fish tissue. An oral route of exposure was employed in this study, in which juvenile yellow perch (Perca flavescens) were given a single oral dose of 5 or 20 μg of microcystin-LR (MC-LR) via food and accumulation in the muscle, liver, and tank water were measured over 24 h. Peak concentrations of the water soluble fraction of microcystin were generally observed 8-10 h after dosing in the liver and after 12-16 h in the muscle, with a rapid decline in both tissues by 24 h. Up to 99% of the total recoverable (i.e., unbound) microcystin was measured in the tank water by 16 h after exposure. The relatively rapid uptake and elimination of the unbound fraction of microcystin in the liver and muscle of juvenile yellow perch within 24 h of exposure indicates that fish consumption may not be a major route of human exposure to microcystin, particularly in the Great Lakes.

  1. Perch, Perca fluviatilis show a directional preference for, but do not increase attacks toward, prey in response to water-borne cortisol

    Directory of Open Access Journals (Sweden)

    Lindsay J. Henderson

    2017-10-01

    Full Text Available In freshwater environments, chemosensory cues play an important role in predator-prey interactions. Prey use a variety of chemosensory cues to detect and avoid predators. However, whether predators use the chemical cues released by disturbed or stressed prey has received less attention. Here we tested the hypothesis that the disturbance cue cortisol, in conjunction with visual cues of prey, elevates predatory behavior. We presented predators (perch, Perca fluviatilis with three chemosensory choice tests and recorded their location, orientation, and aggressive behavior. We compared the responses of predators when provided with (i visual cues of prey only (two adjacent tanks containing sticklebacks; (ii visual and natural chemical cues of prey vs. visual cues only; and (iii visual cues of prey with cortisol vs. visual cues only. Perch spent a significantly higher proportion of time in proximity to prey, and orientated toward prey more, when presented with a cortisol stimulus plus visual cues, relative to presentations of visual and natural chemical cues of prey, or visual cues of prey only. There was a trend that perch directed a higher proportion of predatory behaviors (number of lunges toward sticklebacks when presented with a cortisol stimulus plus visual cues, relative to the other chemosensory conditions. But they did not show a significant increase in total predatory behavior in response to cortisol. Therefore, it is not clear whether water-borne cortisol, in conjunction with visual cues of prey, affects predatory behavior. Our results provide evidence that cortisol could be a source of public information about prey state and/or disturbance, but further work is required to confirm this.

  2. Cadmium-handling strategies in two chronically exposed indigenous freshwater organisms-the yellow perch (Perca flavescens) and the floater mollusc (Pyganodon grandis)

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, Peter G.C. [Universite du Quebec, INRS Eau Terre et Environnement (INRS-ETE), 490 de la Couronne, Que., G1K 9A9 (Canada)]. E-mail: peter_campbell@ete.inrs.ca; Giguere, Anik [Universite du Quebec, INRS Eau Terre et Environnement (INRS-ETE), 490 de la Couronne, Que., G1K 9A9 (Canada); Bonneris, Emmanuelle [Universite du Quebec, INRS Eau Terre et Environnement (INRS-ETE), 490 de la Couronne, Que., G1K 9A9 (Canada); Unite mixte de recherche INRA-DGER-1233, ' Mycotoxines et Toxicologie comparees des xenobiotiques' , 1 av Bourgelat, BP 83, 69290 Marcy l' Etoile (France); Hare, Landis [Universite du Quebec, INRS Eau Terre et Environnement (INRS-ETE), 490 de la Couronne, Que., G1K 9A9 (Canada)

    2005-03-25

    Laboratory experiments on a variety of aquatic organisms suggest that metallothionein-like proteins (MT) play an important role in the regulation of essential metals, and in the sequestration and detoxification of non-essential metals (e.g., Cd). However, the importance of metallothionein production relative to alternative strategies of metal detoxification, and its effectiveness in metal detoxification, remain largely unexplored in field situations. In the present study we explored metal-handling strategies in an adult benthic bivalve (Pyganodon grandis) and in juvenile yellow perch (Perca flavescens), exposed to Cd in their natural habitat. The two biomonitor species were collected from lakes located along a Cd concentration gradient. Ambient dissolved Cd concentrations were determined by in situ dialysis as a measure of metal exposure. Sub-cellular Cd partitioning was determined in target tissues (bivalve gills and digestive gland; perch liver) by differential centrifugation, and metallothionein was measured independently by a mercury-saturation assay in the bivalve tissues. Malondialdehyde concentrations were measured as a potential indicator of oxidative stress. Ambient dissolved Cd concentrations ranged from 0.06 to 0.57 nM in the nine lakes from which bivalves were collected, and from <0.3 to 6.7 nM in the eight lakes from which yellow perch were sampled. Bioaccumulated Cd also varied from lake to lake, more so for the bivalve than for the yellow perch; the [Cd]{sub max}/[Cd]{sub min} ratios for the various tissues decreased in the order: bivalve gill Cd (28) > bivalve digestive gland Cd (18) > perch hepatic Cd (14). In the two lakes that were common to both the bivalve and perch studies, i.e. lakes Opasatica and Vaudray, accumulated Cd concentrations were consistently higher in the bivalve than in the perch. Cadmium-handling strategies were similar in the bivalve digestive gland and perch liver, in that Cd was mainly associated with the heat-stable protein

  3. A multi-level biological approach to evaluate impacts of a major municipal effluent in wild St. Lawrence River yellow perch (Perca flavescens)

    Energy Technology Data Exchange (ETDEWEB)

    Houde, Magali, E-mail: magali.houde@ec.gc.ca [Centre Saint-Laurent, Environment Canada, 105 McGill Street, Montreal, QC H2Y 2E7 (Canada); Giraudo, Maeva, E-mail: maeva.giraudo@ec.gc.ca [Centre Saint-Laurent, Environment Canada, 105 McGill Street, Montreal, QC H2Y 2E7 (Canada); Douville, Mélanie, E-mail: melanie.douville@ec.gc.ca [Centre Saint-Laurent, Environment Canada, 105 McGill Street, Montreal, QC H2Y 2E7 (Canada); Bougas, Bérénice, E-mail: berenice.bougas.1@ulaval.ca [Institut de biologie intégrative et des systèmes, Université Laval, 1030, avenue de la Médecine, Québec, QC G1V 0A6 (Canada); Institut National de la Recherche Scientifique, Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC G1K 9A9 (Canada); Couture, Patrice, E-mail: patrice.couture@ete.inrs.ca [Institut National de la Recherche Scientifique, Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC G1K 9A9 (Canada); De Silva, Amila O., E-mail: amila.desilva@ec.gc.ca [Canada Centre for Inland Waters, Environment Canada, 867 Lakeshore Road, P.O. Box 5050, Burlington, ON L7R 4A6 (Canada); Spencer, Christine, E-mail: christine.spencer@ec.gc.ca [Canada Centre for Inland Waters, Environment Canada, 867 Lakeshore Road, P.O. Box 5050, Burlington, ON L7R 4A6 (Canada); Lair, Stéphane, E-mail: stephane.lair@umontreal.ca [Centre québécois sur la santé des animaux sauvages, Université de Montréal, C.P. 5000, St-Hyacinthe, QC J2S 7C6 (Canada); and others

    2014-11-01

    The development of integrated ecotoxicological approaches is of great interest in the investigation of global concerns such as impacts of municipal wastewater effluents on aquatic ecosystems. The objective of this study was to investigate the effects of a major wastewater municipal effluent on fish using a multi-level biological approach, from gene transcription and enzyme activities to histological changes. Yellow perch (Perca flavescens) were selected based on their wide distribution, their commercial and recreational importance, and the availability of a customized microarray. Yellow perch were sampled upstream of a major municipal wastewater treatment plant (WWTP) and 4 km and 10 km downstream from its point of discharge in the St. Lawrence River (Quebec, Canada). Concentrations of perfluoroalkyl substances (PFASs), polybrominated diphenyl ethers (PBDEs) and metals/trace elements in whole body homogenates were comparable to those from other industrialized regions of the world. Genomic results indicated that the transcription level of 177 genes was significantly different (p < 0.024) between exposed and non-exposed fish. Among these genes, 38 were found to be differentially transcribed at both downstream sites. Impacted genes were associated with biological processes and molecular functions such as immunity, detoxification, lipid metabolism/energy homeostasis (e.g., peroxisome proliferation), and retinol metabolism suggesting impact of WWTP on these systems. Moreover, antioxidant enzyme activities were more elevated in perch collected at the 4 km site. Biomarkers of lipid metabolism, biosynthetic activity, and aerobic capacities were significantly lower (p < 0.05) in fish residing near the outfall of the effluent. Histological examination of the liver indicated no differences between sites. Correlations between PFAS, PBDE, and metal/trace element tissue concentrations and markers of peroxisomal proliferation, oxidative stress, and retinoid metabolism were found

  4. Activity and food choice of piscivorous perch ( Perca fluviatilis ) in a eutrophic shallow lake: a radio-telemetry study

    DEFF Research Database (Denmark)

    Jacobsen, Lene; Berg, Søren; Broberg, M.

    2002-01-01

    1. Radio transmitters were implanted in large perch (27-37 cm) in a shallow lake in Denmark. Between 6 and 13 perch were tracked every 3 h for 24-h periods twice (summer) or once a month (winter) from August 1997 to July 1998. Activity levels were recorded as minimum distance moved per hour. 2....... No significant differences in activity levels of individual fish were observed. 3. Highest activities were observed at daytime with peaks at dawn and dusk or midday. This diel pattern was most pronounced from October to April, whereas diel variations were less in the summer months, with no peaks occurring...... in midsummer. The general lack of activity at night supports the idea that perch is a visually oriented forager. 4. There was no significant relationship between daytime activity during the year and temperature or day length, but nighttime activity was correlated with temperature. In contrast with previous...

  5. How does exposure to nickel and cadmium affect the transcriptome of yellow perch (Perca flavescens) – Results from a 1000 candidate-gene microarray

    Energy Technology Data Exchange (ETDEWEB)

    Bougas, Bérénice, E-mail: Berenice.Bougas@ete.inrs.ca [Institut National de la Recherche Scientifique, Centre INRS Eau Terre et Environnement, 490, rue de la Couronne, Québec, Québec G1K 9A9 (Canada); Département de biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec G1V 0A6 (Canada); Normandeau, Eric [Département de biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec G1V 0A6 (Canada); Pierron, Fabien [Université de Bordeaux, EPOC, UMR 5805, F-33400 Talence (France); CNRS, EPOC, UMR 5805, F-33400 Talence (France); Campbell, Peter G.C. [Institut National de la Recherche Scientifique, Centre INRS Eau Terre et Environnement, 490, rue de la Couronne, Québec, Québec G1K 9A9 (Canada); Bernatchez, Louis [Département de biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec G1V 0A6 (Canada); Couture, Patrice [Institut National de la Recherche Scientifique, Centre INRS Eau Terre et Environnement, 490, rue de la Couronne, Québec, Québec G1K 9A9 (Canada)

    2013-10-15

    Highlights: •The transcriptional responses of Perca flavescens to both metal and non metal stressors were measured with a 1000 candidate-gene microarray. •475, 287 and 176 genes were differentially transcribed depending on temperature, Ni and Cd concentrations, respectively. •Genes involved in iron metabolism, transcriptional and translational processes, vitamin metabolism, blood coagulation, and calcium transport were impacted by metals. •The developed microarray contributes to a better characterization of the impact of different stressors on the transcriptome. -- Abstract: The molecular mechanisms underlying nickel (Ni) and cadmium (Cd) toxicity and their specific effects on fish are poorly understood. Documenting gene transcription profiles offers a powerful approach toward identifying the molecular mechanisms affected by these metals and to discover biomarkers of their toxicity. However, confounding environmental factors can complicate the interpretation of the results and the detection of biomarkers for fish captured in their natural environment. In the present study, a 1000 candidate-gene microarray, developed from a previous RNA-seq study on a subset of individual fish from contrasting level of metal contamination, was used to investigate the transcriptional response to metal (Ni and Cd) and non metal (temperature, oxygen, and diet) stressors in yellow perch (Perca flavescens). Specifically, we aimed at (1) identifying transcriptional signatures specific to Ni and Cd exposure, (2) investigating the mechanisms of their toxicity, and (3) developing a predictive tool to identify the sublethal effects of Ni and Cd contaminants in fish sampled from natural environments. A total of 475 genes displayed significantly different transcription levels when temperature varied while 287 and 176 genes were differentially transcribed at different concentrations of Ni and Cd, respectively. These metals were found to mainly affect the transcription level of genes

  6. The feeding behaviour of large perch Perca fluviatilis (L.) in relation to food availability: a comparative study

    NARCIS (Netherlands)

    Dörner, H.; van den Berg, S.A.; Jacobsen, L.; Hülsmann, S.; Brojerg, M.; Wagner, A.

    2003-01-01

    The aim of the present study was to analyse and compare the feeding behaviour of large perch (>25 cm total length) in two lakes of different state and corresponding differences in food availability. Investigations were conducted in the Bautzen Reservoir, Germany, (biomanipulated, macrophyte cover

  7. Mercury in flounder, Platichtys flesus, cod, Gadus morhua, and perch, Perca fluviatilis, in relation to their length and environment

    Energy Technology Data Exchange (ETDEWEB)

    Luten, J.B.; Bouquet, W.; Riekwel-Booy, G.; Rauchbaar, A.B.; Scholte, M.W.M.

    1987-02-01

    During the last ten years several changes have been taken place in the use of mercury. Industrial discharges have been restricted and several fields of application have been eliminated or reduced. However, the use of mercury containing batteries is still increasing. Monitoring the mercury content of fish is however still an important aspect of environmental pollution control. It has been shown by several investigators that the mercury content in fish might be correlated with biological parameters like length and age. In this paper the results are presented of a few recent Dutch monitoring studies of mercury in flounder, cod and perch in relation to biological and environmental parameters.

  8. Thresholds for opportunistic disease in yellow perch (Perca flavescens) exposed to oil sand process-affected waters

    Energy Technology Data Exchange (ETDEWEB)

    Hogan, N.; Van Den Heuvel, M. [Prince Edward Island Univ., Charlottetown, PE (Canada); Van Meer, T.; Mackinnon, M. [Syncrude Canada Ltd., Edmonton, AB (Canada)

    2010-07-01

    Reclaimed oil sands wetlands will contain process-affected materials with elevated salt, naphthenic acids (NA) and polycyclic aromatic hydrocarbons (PAH). Mature fine tailings may also be placed at the bottom of reclaimed lakes. This study investigated the effects of oil sands-impacted aquatic systems on the health of perch stocked in 2 experimental lakes between 1995 and 1997. A demonstration pond was constructed in 1989 and contained 70,000 m{sup 3} of mature fine tailings capped with 70,000 m{sup 3} of surface water. The South Bison pond was formed in a natural depression in an area where unrecovered bitumen was deposited. The area surrounding the pond was reclaimed for pasture in 1996. Two disease pathologies were observed in perch stocked in both lakes, notably fin erosion caused by an unidentified pathogen, and lymphocystis. The pathologies were initially more prevalent in the South Bison pond. Later studies confirmed that the diseases were substantially more prevalent in the demonstration pond. The study showed that while NA decreased over time in the South Bison pond, NA was doubled in the demonstration pond as a result of tailings densification. The study suggested that temporal changes in NA correlate with the incidence of disease pathologies.

  9. Performances zootechniques comparées de Rotifères d'eau douce Brachionus calyciflorus et de nauplii d'Artemia salina chez les larves de la perche fluviatile Perca fluviatilis

    Directory of Open Access Journals (Sweden)

    Fiogbé, ED.

    2003-01-01

    Full Text Available Zootechnic Performences Compared between Freshwater Rotifer (Brachionus calyciflorus and Nauplii Artemia salina in River Perch Perca fluviatilis L. In able to improve survival rate and growth in perch Perca fluviatilis larvae which are very small at hatching stage, larvae are submitted two days after hatching to different live food: fresh water Rotifer Brachionus calyciflorus and nauplii of Artemia salina.Thus, to avoid the big mortality which occure because of manipulation of larvae, eggs in eye stage were shared in two duplicated groups and feeding of larvae started two days after hatching. Mortality was significant in the two groups from the day 7. However, at the end of the experiment, the group fed Rotifer at the begining of feeding, exhibited the best homogeneity, the best survival and the best food convertion ratio. So, this experiment has shown clearly that at hatching time, all perch larvae are not able to ingest nauplii Artemia. It is necessary to mix their starter food with Rotifer.

  10. De novo transcriptome sequencing and analysis of male, pseudo-male and female yellow perch, Perca flavescens.

    Directory of Open Access Journals (Sweden)

    Yan-He Li

    Full Text Available Transcriptome sequencing could facilitate discovery of sex-biased genes, biological pathways and molecular markers, which could help clarify the molecular mechanism of sex determination and sexual dimorphism, and assist with selective breeding in aquaculture. Yellow perch has unique gonad system and sexual dimorphism and is an alternative model to study mechanism of sex determination, sexual dimorphism and sexual selection. In this study, we performed the de novo assembly of yellow perch gonads and muscle transcriptomes by high throughput Illumina sequencing. A total of 212,180 contigs were obtained, ranging from 127 to 64,876 bp, and N50 of 1,066 bp. The assembly RNA-Seq contigs (≥200bp were then used for subsequent analyses, including annotation, pathway analysis, and microsatellites discovery. No female- and pseudo-male-biased genes were involved in any pathways while male-biased genes were involved in 29 pathways, and neuroactive ligand receptor interaction and enzyme of trypsin (enzyme code, EC: 3.4.21.4 was highly involved. Pyruvate kinase (enzyme code, EC: 2.7.1.40, which plays important roles in cell proliferation, was highly expressed in muscles. In addition, a total of 183,939 SNPs, 11,286 InDels and 41,479 microsatellites were identified. This study is the first report on transcriptome information in Percids, and provides rich resources for conducting further studies on understanding the molecular basis of sex determinations, sexual dimorphism, and sexual selection in fish, and for population studies and marker-assisted selection in Percids.

  11. A combined food web toxicokinetic and species bioenergetic model for predicting seasonal PCB elimination by yellow perch (Perca flavescens).

    Science.gov (United States)

    Drouillard, Ken G; Paterson, Gordon; Haffner, G Douglas

    2009-04-15

    A commonly used toxicokinetic model was coupled to a bioenergetic submodel optimized for yellow perch and an empirical growth submodel to predict daily PCB elimination flux in three size classes of fish under seasonally variable temperatures. Across seasons, the bioenergetic model predicted highly variable gill ventilation and fecal egestion rates which varied by 74.2-111.2 fold and 35-65 fold, respectively, over the annual cycle. The empirical growth model accounted for seasonal trends in overwintering lipid losses evident for all fish size classes and growth, evident only for the small fish size class, during warm water periods. The toxicokinetic model described seasonal trends in congener specific PCB mass balance of fish, but tended to overestimate PCB elimination for less hydrophobic congeners when the recommended gill transfer efficiency term (Ew) of 0.54 was used. Downward adjustment of Ew to an average value of 0.14 produced the strongest model fit for several low Kow PCBs but had less effect on model performance for mid- to high Kow congeners. The toxicokinetic model was less sensitive to parameters involved in fecal elimination of PCBs when applied to low and mid-Kow PCBs. This study demonstrates the importance of seasonal trends in metabolic rate, growth, and overwintering weight loss as factors that modify PCB toxicokinetics in temperate fish.

  12. Anti-oxidative effects of some dietary supplements on Yellow perch (Perca flavescens exposed to different physical stressors

    Directory of Open Access Journals (Sweden)

    Hiam Elabd

    2017-11-01

    Full Text Available In current study, Yellow perch (P. flavescens was exposed to common forms of physical stressors and antioxidative effects of dietary incorporated Astragalus membranaceus (AM and Glycyrrhiza glabra (liquorice were assessed. To address this, for a four-week five groups of fish (31 ± 1.0 g, average weight received 1, 2, and 3% (w/w Glycyrrhiza glabra; and 1% G. glabra- A. membranaceus mixture daily. Control group fed an additive-free basal diet. Immunological, biochemical and histopathological profiles were evaluated; and fish were redistributed to be exposed to heat, cold, hypoxia and capture stressors. The current findings demonstrated that A. membranaceus and G. glabra dietary incorporation remarkably enhanced antioxidative and biochemical parameters. Also, the study showed markedly up-regulation of related genes expression; and revealed better liver histology in supplemented groups over the control. In conclusion, A. membranaceus and G. glabra dietary supplementation markedly enhanced antioxidantive responses throughout the experimental period, indicating the ability of both herbal plants to confer protection against different physical stressors.

  13. Perca fluviatilis L.

    African Journals Online (AJOL)

    AISA

    Pour une meilleure survie, les larves de la perche fluviatile Perca fluviatilis L., qui sont en général de petite taille, ont été nourries, dès l'éclosion, avec deux proies vivantes : le Rotifère d'eau douce (Brachionus calyciflorus) et le nauplii d'Artemia salina. Pour minimiser les mortalités dues aux manipulations des larves.

  14. Hanging out at the airport: Unusual upside-down perching behavior by Eurasian Jackdaws (Corvus monedula) in a human-dominated environment

    Science.gov (United States)

    Katzner, Todd E.

    2016-01-01

    Animals occupying human-dominated environments show the capacity for behavioral flexibility. Corvids are among the most intelligent synanthropic bird species. During a layover at Schipol Airport in Amsterdam, Netherlands, I photographically documented Eurasian Jackdaws (Corvus monedula) perching upside down from a building cornice. In contrast to other reports of hanging birds, these jackdaws did not forage or play while upside down and appeared to use the perching spot to observe their surroundings. Although Corvids and Psittacines are known to hang upside down, especially in captive situations, such behaviors are rarely documented in the wild, and never before in association with human-built structures.

  15. Impact of the cestode Triaenophorus nodulosus on the exotic Lepomis gibbosus and the autochthonous Perca fluviatilis.

    Science.gov (United States)

    Masson, G; Vanacker, M; Fox, M G; Beisel, J-N

    2015-05-01

    The effects of plerocercoids of the cestode Triaenophorus nodulosus infecting the livers of native Eurasian perch Perca fluviatilis and non-native pumpkinseed Lepomis gibbosus was investigated in 17 sites along the Moselle watershed. With a single exception, infected individuals were not observed in the main channel whether or not northern pike Esox lucius, a final host, was present. In ponds where the pike was present, the prevalence of T. nodulosus averaged 86% in Eurasian perch and 15% in pumpkinseed. The parasite was not present at all in ponds when pike were absent. Parasite load, hepatosomatic index (HSI), gonadosomatic index (GSI) and body condition index (CI) were compared between hosts in one site where parasite prevalence and fish abundance was highest. HSI in infected perch was significantly higher than in uninfected perch, whereas no differences in HSI were detected between infected and uninfected pumpkinseed. While perch were more frequently infected and had a greater average parasite load than pumpkinseed, there were no significant differences in either indicator between the two species. Furthermore, no significant differences in GSI or CI were observed between infected and uninfected fish in either species, by either gender or maturity stage. We hypothesize that pumpkinseed is more resistant to the parasite or less likely to feed upon infected copepods than perch.

  16. Contribution à l'étude des besoins nutritionnels chez les larves et juvéniles de la perche fluviatile (Perca fluviatilis L.

    Directory of Open Access Journals (Sweden)

    Fiogbé, ED.

    2003-01-01

    Full Text Available Contribution to the Study of the Nutrional Requirements in the Larvas and Juveniles of the River Perch (Perca fluviatilis L.. Les possibilités d'introduction de la petite motorisation dans le secteur maraîcher du Sahel tunisien ont été étudiées par la conduite d'une enquête auprès d'exploitants maraîchers de la région visant la collecte de données précises sur les caractéristiques de l'exploitation (taille et nombre de parcelles, spéculations pratiquées, mécanisation adoptée, etc., et le diagnostic de la petite motorisation disponible sur le marché local (nature, puissance, etc.. Les résultats ont montré une dominance des exploitations de petite taille constituées pour la plupart de deux parcelles séparées et pratiquant plusieurs spéculations. Au niveau de ces exploitations qui sont gérées dans la majorité par des agriculteurs jeunes mais d'une grande expérience, seul le travail du sol était entièrement motorisé. La motorisation faisait appel à des engins de traction de taille et puissance importante (plus de 50 kW. Au niveau du marché local, la petite motorisation était représentée par des motohoues de puissance comprise entre 5 et 7 kW, des motoculteurs dont la puissance est comprise entre 6 et 10,5 kW et de deux types de petits tracteurs de puissance respective 12 et 16 kW. Il s'est avéré que toutes les opérations culturales motorisées disposaient des outils attelables correspondants. De même, plusieurs autres opérations pouvaient être motorisées (binage, buttage, traitement phytosanitaire.

  17. 62 years of population dynamics of European perch (Perca fluviatilis) in a mesotrophic lake tracked using angler diaries: The role of commercial fishing, predation and temperature

    DEFF Research Database (Denmark)

    Skov, Christian; Jansen, Teunis; Arlinghaus, Robert

    2017-01-01

    the harvest of pike, the top predator of the lake. The size distribution and growth rates of perch caught by anglers also changed substantially during the study period, most likely controlled by density-dependent mechanisms as well as size-selective commercial harvest. The effect of selective harvest on size......Standardised angler diaries could produce useful proxy data for assessing fish population density and size distribution, but few rigorous studies about their utility exist. We use 62 years of angling diary data (1949–2010), from a large mesotrophic lake, to investigate population structure......, indicating large variation in population abundance over decadal time scales. Our statistical analysis revealed that the anglers’ harvest rates of perch were related to pike CPUE (proxy of pike predation), temperature and commercial fishing directly through the harvest of perch and indirectly through...

  18. Physiological-biochemical status of perch (Perca fluviatilis Linnaeus, 1758 and roach in conditions (Rutilus rutilus Linnaeus, 1758 of excessive anthropogenic pressure on the body of water

    Directory of Open Access Journals (Sweden)

    V. Martseniuk

    2017-12-01

    Full Text Available Purpose. To establish during the spring and summer period the physiologically-biochemical response of fish to the effect of excessive anthropogenic contamination on the indicators of the maintenance of hormones and glucose in their blood plasma, and the possibility of using these indicators to assess the ecological status of the water body. Methodology. Two Lakes in the city of Kyiv were selected for research, which are characterized by various hydrochemical and toxicological indices. These water objects were Lake Kyrylivske (Opechen Upper – a water body from the system of Lakes Opechen (polluted by the water body and Lake Babyne that is on Trukhanov Island (relatively clean Lake, control. Fishing was carried out in the early spring and in the middle of the summer by hook fishing gear. In laboratory conditions, the total content of thyroxine (T4, triiodothyronine (T3 and cortisol in blood plasma of fish was determined by enzyme immunoassay, using commercial T3-EIA, T4-EIA sets (NPL Granum, Ukraine and DS-EIA-Steroid-Cortisol ("Diagnostic Systems" NGO, Russia using the Rayto RT-2100C EIA Analyzer. The glucose content was determined by spectrophotometrically glucose oxidase method using standard commercial kits "Filisit-Diagnostika" (Ukraine. Statistical data was processed using the programs Statistica 10.0 and Excel programs from the Microsoft Office suite. Findings. In the spring, excessive anthropogenic pressure on the Lake Kyrylivske causes an energy imbalance in fish, which causes the deceleration of catabolic reactions in their tissues. In this period, the perch and roach react to the conditions of existence in the Lake Kyrylivske increase in the content of cortisol in the blood compared with fish from the Lake. Babyne, what can be their reaction to excessive anthropogenic stress. Also, during this period, the low content of thyroxin and triiodothyronine in the perch from the Lake Kyrylivske was noted compared with the Lake. Babyne, which

  19. Combined effects of temperature and metal exposure on the fatty acid composition of cell membranes, antioxidant enzyme activities and lipid peroxidation in yellow perch (Perca flavescens)

    Energy Technology Data Exchange (ETDEWEB)

    Fadhlaoui, Mariem; Couture, Patrice, E-mail: patrice.couture@ete.inrs.ca

    2016-11-15

    Highlights: • The fatty acid composition of yellow perch muscle at 9 °C was enhanced in monounsaturated and polyunsaturated fatty acids compared to fish maintained at 28 °C. • The thermal adjustment of muscle phospholipid fatty acid profiles is likely due to modifications of desaturase and elongase activities. • Exposure to Ni and Cd modified muscle phospholipid fatty acid composition in a temperature-dependent manner. • The higher fatty polyinsaturation in cold-acclimated fish did not increase their vulnerability to peroxidation. • Lower concentrations of malondialdehyde were measured in warm-acclimated, Ni-exposed fish, suggesting an overcompensation of antioxidant mechanisms that could explain their lower condition. - Abstract: The aim of this study was to investigate the combined effects of temperature and metal contamination (cadmium and nickel) on phospholipid fatty acid composition, antioxidant enzyme activities and lipid peroxidation in fish. Yellow perch were acclimated to two different temperatures (9 °C and 28 °C) and exposed either to Cd or Ni (respectively 4 μg/L and 600 μg/L) for seven weeks. Superoxide dismutase, catalase, glutathione-S-transferase, glutathione peroxidase activities and glutathione concentration were measured as indicators of antioxidant capacities, while malondialdehyde concentration was used as an indicator of lipid peroxidation. Poikilotherms including fish counteract the effects of temperature on phospholipid fatty acid ordering by remodelling their composition to maintain optimal fluidity. Accordingly, in our study, the fatty acid composition of yellow perch muscle at 9 °C was enhanced in monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA) compared to fish maintained at 28 °C, in agreement with the theory of homeoviscous adaptation. Using ratios of various fatty acids as surrogates for desaturase and elongase activities, our data suggests that modification of the activity of these enzymes is

  20. Combined effects of temperature and metal exposure on the fatty acid composition of cell membranes, antioxidant enzyme activities and lipid peroxidation in yellow perch (Perca flavescens).

    Science.gov (United States)

    Fadhlaoui, Mariem; Couture, Patrice

    2016-11-01

    The aim of this study was to investigate the combined effects of temperature and metal contamination (cadmium and nickel) on phospholipid fatty acid composition, antioxidant enzyme activities and lipid peroxidation in fish. Yellow perch were acclimated to two different temperatures (9°C and 28°C) and exposed either to Cd or Ni (respectively 4μg/L and 600μg/L) for seven weeks. Superoxide dismutase, catalase, glutathione-S-transferase, glutathione peroxidase activities and glutathione concentration were measured as indicators of antioxidant capacities, while malondialdehyde concentration was used as an indicator of lipid peroxidation. Poikilotherms including fish counteract the effects of temperature on phospholipid fatty acid ordering by remodelling their composition to maintain optimal fluidity. Accordingly, in our study, the fatty acid composition of yellow perch muscle at 9°C was enhanced in monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA) compared to fish maintained at 28°C, in agreement with the theory of homeoviscous adaptation. Using ratios of various fatty acids as surrogates for desaturase and elongase activities, our data suggests that modification of the activity of these enzymes is responsible for the thermal acclimation of phospholipid fatty acid profiles. However, this response was altered under Ni and Cd exposure: PUFA decreased (specifically n-6 PUFA) while the proportion of saturated fatty acids increased at 9°C, whereas at 28°C, PUFA increased to proportions exceeding those observed at 9°C. Lipid peroxidation could be observed under all experimental conditions. Both enzymatic and non-enzymatic antioxidant defense systems acted cooperatively to cope with oxidative stress leading to lipid peroxidation, which was not affected by temperature acclimation as indicated by malondialdehyde concentration, in spite of a higher polyinsaturation in cold-acclimated fish which would be predicted to increase their vulnerability to

  1. Expression of Hsp70, Igf1, and Three Oxidative Stress Biomarkers in Response to Handling and Salt Treatment at Different Water Temperatures in Yellow Perch, Perca flavescens

    Directory of Open Access Journals (Sweden)

    Nour Eissa

    2017-09-01

    Full Text Available Stress is a major factor that causes diseases and mortality in the aquaculture industry. The goal was to analyze the expression of stress-related biomarkers in response to different stressors in yellow perch, which is an important aquaculture candidate in North America and highly sensitive to handling in captivity. Three fish groups were established, each having four replicates, and subjected to water temperatures of 14, 20, and 26°C and acute handling stress was performed followed by a salt treatment for 144h at a salinity of 5 ppt. Serum and hepatic mRNA levels of heat shock protein (hsp70, insulin-like growth factor 1 (Igf1, glutathione peroxidase (Gpx, superoxide dismutase 1 (Sod1, and glutathione reductase (Gsr were quantified at seven times interval over 144 h using ELISA and RT-qPCR. Handling stress caused a significant down-regulation in Hsp70, Gpx, Sod1, and Gsr at a water temperature of 20°C compared to 14 and 26°C. Igf1 was significantly upregulated at 20°C and down-regulated at 14 and 26°C. Salt treatment had a transient reverse effect on the targeted biomarkers in all groups at 72 h, then caused an upregulation after 144 h, compared to the control groups. The data showed a negative strong regulatory linear relationship between igf1 with hsp70 and anti-oxidative gene expressions. These findings could provide valuable new insights into the stress responses that affect fish health and could be used to monitor the stress.

  2. Annual Developmental Cycle of Gonads of European Perch Females (Perca fluviatilis L.) from Natural Sites and a Canal Carrying Post-cooling Water from the Dolna Odra Power Plant (NW Poland).

    Science.gov (United States)

    Kirczuk, Lucyna; Domagała, Józef; Pilecka-Rapacz, Małgorzata

    2015-01-01

    The European perch is a species endowed with high adaptation capabilities as regards different environmental conditions. The aim of the study was to analyse the annual developmental cycle of ovaries of the European perch from the Oder river, Lake Dąbie and a drainage canal (Warm Canal) carrying post-cooling water from the Dolna Odra power plant (annual average water temperature in the canal is higher by 6-8°C than the water of the other sampling sites). Most of the female perch caught in the canal carrying post-cooling water had immature stage 2 gonads (delayed development of the gonads) and were smaller than the fish from the other sites. No traces of spawning in the form of deposed egg strings were found in the drainage canal. Adult individuals avoid high temperatures found in the Warm Canal. In April, in perch from all sites, ovaries with post-spawning oocytes were observed. The spawning season of the females lasted from the beginning of April until May. Stage 4 of gonad development, with oocytes in advanced vitellogenesis, was the longest and ranged from September through February.

  3. Perch Rhabdovirus

    OpenAIRE

    Institute, Marine

    2011-01-01

    This leaflet gives information on perch rhabdovirus. Rhabdoviruses of the genus Vesiculovirus are an emerging group of pathogenic viruses and include perch rhabdovirus, pike-fry rhabdovirus, tench rhabdovirus, lake trout rhabdovirus and spring viraemia of carp virus.

  4. Chemometric analysis of fatty acids profile of bream (Abramis brama, ruffe (Gymnocephalus cernua and perch (Perca fluviatilis meat from Lake Gopło and Włocławski Dam Reservoir

    Directory of Open Access Journals (Sweden)

    Bogumila Kupcewicz

    2012-01-01

    Full Text Available The 18 fatty acid profiles have been determined in 63 samples of muscles from three freshwater fish species: bream, ruffe and perch by gas chromatography method. The fish were collected in natural condition from two reservoirs located in central Poland: Lake Gopło and Włocławski Reservoir. A chemometric study with the use of hierarchical cluster analysis (HCA, principal component (PCA and stepwise linear discrimination analysis (LDA was applied to characterize, classify and differentiate collected samples. The chemometric techniques by using fatty acids content as descriptors allow clearly distinguish 6 groups according to fish species and their geographical origin.

  5. Scaling the sublethal effects of methylmercury to yellow perchs population dynamics using adverse outcome pathway framework

    Science.gov (United States)

    This study sought to evaluate the effects of environmentally relevant dietary MeHg exposures on adult female yellow perch (Perca flavescens) and zebrafish (Danio rerio) reproduction. Yellow perch were used in the study for their socioeconomic and ecological importance within the Great Lakes basin, a...

  6. Rapid proliferation of an endemic galaxiid following eradication of an alien piscivore (Perca fluviatilis) from a reservoir.

    Science.gov (United States)

    Beatty, S J; Morgan, D L

    2017-03-01

    Following the complete eradication of the alien piscivorous perch Perca fluviatilis from a potable reservoir, the abundance of the endemic western minnow Galaxias occidentalis, which was previously undetectable prior to the initial eradication event, increased dramatically. The study reveals the potential of reservoirs to act as ecological refuges and has implications for understanding the relative effects of alien fishes v. habitat alteration on native freshwater fishes. © 2016 The Fisheries Society of the British Isles.

  7. PENGOLAHAN KAIN PERCA MENJADI SEKAT PEREDAM SUARA

    Directory of Open Access Journals (Sweden)

    Patricia Pahlevi Noviandri

    2016-12-01

    Full Text Available Permasalahan sampah di Indonesia sangat tinggi. Sebanyak 2% dari total sampah di Indonesia berasal dari kain. Pengolahan 2% limbah kain ini dinilai mampu meningkatkan perekonomian warga. Berbagai macam pengolahan limbah kain diantaranya menjadi tas, selimut, sandal, tatakan meja, maupun keset mampu bersaing dengan produk industri besar. Inovasi dalam pengolahan limbah kain saat ini sebagai sekat ruangan. Sekat ruangan yang bersifat temporer untuk rumah tinggal saat ini diindikasi mampu untuk memisahkan ruang secara visual namun tidak mampu memisahkan suara antar ruang yang satu dengan yang lain. Penelitian ini bertujuan mendapatkan olahan bahan kain yang efektif meredam suara dengan metode eksperimen. Pengujian dilakukan dengan menggunakan beberapa sampel dengan tiap sampel diberikan beberapa tingkat bunyi (125 Hz hingga 2000 Hz. Variabel pembeda sampel berupa material sekat yaitu kain perca berbahan jeans dan kain perca berbahan katun. Manfaat dari hasil penelitian ini yaitu mendapatkan desain partisi yang memenuhi aspek keindahan untuk dekorasi ruang dan memenuhi aspek akustik sebagai peredam suara tingkat rumah tinggal. Hasil dari penelitian ini yaitu olahan kain perca berupa gempal efektif meredam suara dan memberikan motif dekorasi yang unik. Kemampuan sekat dari olahan kain perca ini dalam meredam suara sebesar 6 dB sampai 15 dB dilihat dari nilai tingkat penurunan kebisingannya. Olahan kain perca dapat meredam suara pada frekuensi yang dihasilkan oleh suara manusia (<2000Hz. 

  8. Susceptibility of Koi and Yellow Perch to infectious hematopoietic necrosis virus by experimental exposure

    Science.gov (United States)

    Palmer, Alexander D.; Emmenegger, Eveline J.

    2014-01-01

    Infectious hematopoietic necrosis virus (IHNV) is a novirhabdoviral pathogen that originated in western North America among anadromous Pacific salmonids. Severe disease epidemics in the late 1970s resulting from IHNV's invasion into farmed Rainbow Trout Oncorhynchus mykiss in North America, Asia, and Europe emphasized IHNV's ability to adapt to new hosts under varying rearing conditions. Yellow Perch Perca flavescens and Koi Carp Cyprinus carpio (hereafter, “Koi”) are aquaculture-reared fish that are highly valued in sport fisheries and the ornamental fish trade, respectively, but it is unknown whether these fish species are vulnerable to IHNV infection. In this study, we exposed Yellow Perch, Koi, and steelhead (anadromous Rainbow Trout) to IHNV by intraperitoneal injection (106 PFU/fish) and by immersion (5.7×105 PFU/mL) for 7 h, and monitored fish for 28 d. The extended immersion exposure and high virus concentrations used in the challenges were to determine if the tested fish had any level of susceptibility. After experimental exposure, Yellow Perch and Koi experienced low mortality (35%). Virus was found in dead fish of all species tested and in surviving Yellow Perch by plaque assay and quantitative reverse transcription polymerase chain reaction (qPCR), with a higher prevalence in Yellow Perch than Koi. Infectious virus was also detected in Yellow Perch out to 5 d after bath challenge. These findings indicate that Yellow Perch and Koi are highly resistant to IHNV disease under the conditions tested, but Yellow Perch are susceptible to infection and may serve as possible virus carriers.

  9. Effects of long-term changes in the benthic community on yellow perch in Saginaw Bay, Lake Huron

    Science.gov (United States)

    Schaeffer, Jeffrey S.; Diana, James S.; Haas, Robert C.

    2000-01-01

    Abundance, mortality, age and growth, food habits, and energetics of a yellow perch Perca flavescens population were investigated in eutrophic Saginaw Bay, Lake Huron during May to October, 1986 to 1988, and compared population characteristics with historical data from times when eutrophic conditions were less severe. During 1986 to 1988, yellow perch were abundant, but grew slowly and experienced high natural mortality. A size threshold was present at 150 to 180 mm beyond which few individuals survived, and sex ratios became biased toward males. An energetic model suggested that yellow perch were food limited; as they increased in size they spent a greater proportion of the growing season near maintenance ration. Low feeding rates were a consequence of subsistence on small chironomid larvae. Piscivory provided little energetic relief. Historical data suggested that availability of large benthic prey such as nymphs of the burrowing mayfly Hexagenia was important to yellow perch. Yellow perch formerly consumed Hexagenia, but mayflies were extirpated from Saginaw Bay during 1953 to 1965, and never recovered. When Hexagenia was present, yellow perch growth was moderate to fast depending on population size, size thresholds were not present, and yellow perch reached large size and older age despite moderate to high fishing mortality. Decreases in yellow perch growth rates during 1952 to 1955 coincided with extirpation of Hexagenia. Fast growth of yellow perch did occur after Hexagenia became extirpated, but only when fishing mortality was high, population size was small, and some large benthic invertebrates remained. Eutrophication of Saginaw Bay appeared to affect yellow perch by changing species composition and reducing size structure of the benthic community.

  10. Evaluation of daily creel and minimum length limits for Black Crappies and Yellow Perch in Wisconsin

    Science.gov (United States)

    Mosel, Kyle; Isermann, Daniel A.; Hansen, Jonathan F.

    2015-01-01

    Harvest regulations for Black Crappie Pomoxis nigromaculatus and Yellow Perch Perca flavescens in the northern USA and Canada have not been thoroughly evaluated, and specific guidance regarding where minimum length limits (MLLs) might improve these fisheries is lacking. We examined whether: (1) transitioning from an aggregate statewide daily creel limit of 25 panfish to species-specific daily creel limits of managers to make more informed decisions regarding harvest regulations, but more information regarding angler preferences is needed for selecting appropriate management objectives and harvest regulations.

  11. Angling web forums as an additional tool for detection of new fish introductions: the first record of Perca fluviatilis in continental Portugal

    Directory of Open Access Journals (Sweden)

    Banha F.

    2015-01-01

    Full Text Available This work reports for the first time the presence of a non-native fish, the European Perch (Perca fluviatilis, in continental Portugal. The presence of this species was first reported on an angling web forum and its occurrence was scientifically confirmed later in a small reservoir of the Tagus river basin, located in the central region of Portugal. The importance of the angling web forums as a useful tool to help detection of non-native fish species introductions and their potential for education on biological invasions is discussed.

  12. Modeling turbidity type and intensity effects on the growth and starvation mortality of age-0 yellow perch

    Science.gov (United States)

    Manning, Nathan M; Bossenbroek, Jonathan M.; Mayer, Christine M.; Bunnell, David B.; Tyson, Jeff T.; Rudstam, Lars G.; Jackson, James R.

    2014-01-01

    We sought to quantify the possible population-level influence of sediment plumes and algal blooms on yellow perch (Perca flavescens), a visual predator found in systems with dynamic water clarity. We used an individual-based model (IBM), which allowed us to include variance in water clarity and the distribution of individual sizes. Our IBM was built with laboratory data showing that larval yellow perch feeding rates increased slightly as sediment turbidity level increased, but that both larval and juvenile yellow perch feeding rates decreased as phytoplankton level increased. Our IBM explained a majority of the variance in yellow perch length in data from the western and central basins of Lake Erie and Oneida Lake, with R2 values ranging from 0.611 to 0.742. Starvation mortality was size dependent, as the greatest daily mortality rates in each simulation occurred within days of each other. Our model showed that turbidity-dependent consumption rates and temperature are key components in determining growth and starvation mortality of age-0 yellow perch, linking fish production to land-based processes that influence water clarity. These results suggest the timing and persistence of sediment plumes and algal blooms can drastically alter the growth potential and starvation mortality of a yellow perch cohort.

  13. Yellow perch (Perca flavescens) mercury unaffected by wildland fires in northern Minnesota

    Science.gov (United States)

    Charlotte E. Riggs; Randall K. Kolka; Edward A. Nater; Emma L. Witt; Trent R. Wickman; Laurel G. Woodruff; Jason T. Butcher

    2017-01-01

    Wildland fire can alter mercury (Hg) cycling on land and in adjacent aquatic environments. In addition to enhancing local atmospheric Hg redeposition, fire can influence terrestrial movement of Hg and other elements into lakes via runoff from burned upland soil. However, the impact of fire on water quality and the accumulation of Hg in fish remain equivocal. We...

  14. Behavioural strategy of large perch Perca fluviatilis varies between a mesotrophic and a hypereutrophic lake

    DEFF Research Database (Denmark)

    Jacobsen, Lene; Berg, Søren; Baktoft, Henrik

    2015-01-01

    pelagic residency during daytime towards the littoral zone at night. In contrast, P. fluviatilis in the hypereutrophic lake were active during the entire diel cycle and were spread throughout the lake also during dark. During winter, crepuscular patterns of activity were seen in both lakes. Condition...

  15. Effect of Feeding-Fasting Cycles on Oxygen Consumption and Bioenergetics of Yellow Perch

    Science.gov (United States)

    Chipps, Steven R.; Travis W. Schaeffer,; Daniel E. Spengler,; Casey W. Schoenebeck,; Michael L. Brown,

    2012-01-01

    We measured growth and oxygen consumption of age-1 yellow perch Perca flavescenssubjected to ad libitum (control) or variable feeding cycles of 2 (i.e., 2 d of feed, 2 d of deprivation), 6, or 12 d for a 72-d period. Individual, female yellow perch (initial weight = 51.9 ± 0.9 g [mean ± SE]) were stocked in 110-L aquaria to provide six replicates per treatment and fed measured rations of live fathead minnow Pimephales promelas. Consumption, absolute growth rate, growth efficiency, and oxygen consumption were similar among feeding regimens. However, growth trajectories for fish on the 2-d cycle were significantly lower than other feed–fast cycles. Hyperphagia occurred in all treatments. Bioenergetics model simulations indicated that consumption was significantly underestimated (t = 5.4, df = 4, P = 0.006), while growth was overestimated (t = −5.5, df = 4, P = 0.005) for fish on the 12-d cycle. However, model errors detected between observed and predicted values were low, ranging from −10.1% to +7.8%. We found that juvenile yellow perch exhibited compensatory growth (CG), but none of the feed–fast treatments resulted in growth overcompensation. Likewise, we found no evidence that respiration rates varied with CG, implying that yellow perch bioenergetics models could be used to predict the effects of feeding history and CG response on food consumption and fish growth.

  16. Development Stability and Cytogenetic Homeostasis of Perca Fluviatilis (Perciformes, Percidae in the Rivers of Rivne Region

    Directory of Open Access Journals (Sweden)

    Klimenko M. O.

    2016-12-01

    Full Text Available The article presents the results of the study on nuclear damages or injuries of red blood cells (RBCs and asymmetry of meristic characters of the European perch (Perca fluviatilis Linnaeus 1758 that lives in small and medium rivers of Rivne Region. The research has found that the species representatives living in the small rivers demonstrated worse cytogenetic homeostasis indicators compared to the fish from the medium rivers: the lowest frequency of P. fluviatilis’ nuclear damages appeared to be 4.25 times higher for the individuals living in the small rivers given the noticeable excess of spontaneous mutations by average damage frequency. Fish morphological homeostasis demonstrates a tendency to injuries in small rivers as well. The functional relationships between the studied parameters which have been established by the author were “close” for the fish from the small rivers and primary “moderate” for the fish from the medium rivers. It is concluded that the enhanced activity of the stressors existing in the water environment affects the physiological state of the P. fluviatilis species.

  17. Lake Erie Yellow perch age estimation based on three structures: Precision, processing times, and management implications

    Science.gov (United States)

    Vandergoot, C.S.; Bur, M.T.; Powell, K.A.

    2008-01-01

    Yellow perch Perca flavescens support economically important recreational and commercial fisheries in Lake Erie and are intensively managed. Age estimation represents an integral component in the management of Lake Erie yellow perch stocks, as age-structured population models are used to set safe harvest levels on an annual basis. We compared the precision associated with yellow perch (N = 251) age estimates from scales, sagittal otoliths, and anal spine sections and evaluated the time required to process and estimate age from each structure. Three readers of varying experience estimated ages. The precision (mean coefficient of variation) of estimates among readers was 1% for sagittal otoliths, 5-6% for anal spines, and 11-13% for scales. Agreement rates among readers were 94-95% for otoliths, 71-76% for anal spines, and 45-50% for scales. Systematic age estimation differences were evident among scale and anal spine readers; less-experienced readers tended to underestimate ages of yellow perch older than age 4 relative to estimates made by an experienced reader. Mean scale age tended to underestimate ages of age-6 and older fish relative to otolith ages estimated by an experienced reader. Total annual mortality estimates based on scale ages were 20% higher than those based on otolith ages; mortality estimates based on anal spine ages were 4% higher than those based on otolith ages. Otoliths required more removal and preparation time than scales and anal spines, but age estimation time was substantially lower for otoliths than for the other two structures. We suggest the use of otoliths or anal spines for age estimation in yellow perch (regardless of length) from Lake Erie and other systems where precise age estimates are necessary, because age estimation errors resulting from the use of scales could generate incorrect management decisions. ?? Copyright by the American Fisheries Society 2008.

  18. Live transport of Yellow Perch and Nile Tilapia in AQUI-S 20E (10% Eugenol) at high loading densities

    Science.gov (United States)

    Cupp, Aaron R.; Schreier, Theresa M.; Schleis, Sue M.

    2017-01-01

    Fish transport costs are a substantial portion of the operational expenses for aquaculture facilities in the USA. Safely transporting higher loading densities of fish would benefit haulers by increasing efficiency and reducing costs, but research evaluating transport for individual species is generally lacking. In this study, Yellow Perch Perca flavescens and Nile Tilapia Oreochromis niloticus were transported for 6 h immersed in water containing AQUI-S 20E (10% eugenol) at fish loading densities of 240 g/L (2 lb/gal) for perch and 480 g/L (4 lb/gal) for tilapia. Survival was quantified for fish transported in AQUI-S 20E concentrations of (1) control or 0 mg/L of water, (2) 100 mg/L, or (3) 200 mg/L. Yellow Perch had 98–100% survival, and Nile Tilapia had 100% survival up to through 14 d after transport across all AQUI-S 20E levels, including the control. Eugenol concentrations decreased rapidly in transport tank water, and fish showed no signs of sedation by the end of transport. We conclude that live transport of Yellow Perch and Nile Tilapia at higher loading densities resulted in high survival regardless of the AQUI-S 20E concentrations we tested.

  19. Impact of different colours of artificial light at night on melatonin rhythm and gene expression of gonadotropins in European perch.

    Science.gov (United States)

    Brüning, Anika; Hölker, Franz; Franke, Steffen; Kleiner, Wibke; Kloas, Werner

    2016-02-01

    The distribution and intensity of artificial light at night, commonly referred to as light pollution, is consequently rising and progressively also ecological implications come to light. Low intensity light is known to suppress nocturnal melatonin production in several fish species. This study aims to examine the least suppressive light colour for melatonin excreted into the holding water and the influence of different light qualities and quantities in the night on gene expression of gonadotropins in fish. European perch (Perca fluviatilis) were exposed to light of different wavelengths during the night (blue, green, and red). Melatonin concentrations were measured from water samples every 3h during a 24h period. Gene expression of gonadotropins was measured in perch exposed to different light colours and was additionally examined for perch subjected to different intensities of white light (0 lx, 1 lx, 10 lx, 100 lx) during the night. All different light colours caused a significant drop of melatonin concentration; however, blue light was least suppressive. Gene expression of gonadotropins was not influenced by nocturnal light of different light colours, but in female perch gonadotropin expression was significantly reduced by white light already at the lowest level (1 lx). We conclude that artificial light with shorter wavelengths at night is less effective in disturbing biological rhythms of perch than longer wavelengths, coinciding with the light situation in freshwater habitats inhabited by perch. Different light colours in the night showed no significant effect on gonadotropin expression, but white light in the night can disturb reproductive traits already at very low light intensities. These findings indicate that light pollution has not only the potential to disturb the melatonin cycle but also the reproductive rhythm and may therefore have implications on whole species communities. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Plasma osmolality and oxygen consumption of perch Perca fluviatilis in response to different salinities and temperatures

    DEFF Research Database (Denmark)

    Christensen, Emil Aputsiaq Flindt; Svendsen, Morten Bo Søndergaard; Steffensen, John Fleng

    2017-01-01

    with salinity at 10 and 20° C. Maximum metabolic rate (MMR) and aerobic scope was lowest at salinity of 15 at 5° C, yet at 20° C, they were lowest at a salinity of 0. A cost of osmoregulation (SMR at a salinity of 0 and 15 compared with SMR at a salinity of 10) could only be detected at a salinity of 15 at 20...... of osmoregulation (28%) at a salinity of 15 at 20° C indicates that the cost of osmoregulation in P. fluviatilis increases with temperature under hyperosmotic conditions and a power analysis showed that the cost of osmoregulation could be lower than 12·5% under other environmental conditions. The effect of salinity...

  1. The biology of perch and related fish

    National Research Council Canada - National Science Library

    Craig, John F; Craig, John

    1987-01-01

    This book presents a definitive volume on perch and related fish. In the introduction an outline is given on the characteristics of the order Perciformes, the suborder Percoidea and the family Percidae...

  2. Transcriptional and biochemical markers in transplanted Perca flavescens to characterize cadmium- and copper-induced oxidative stress in the field

    Energy Technology Data Exchange (ETDEWEB)

    Defo, Michel A. [Institut National De La Recherche Scientifique (INRS), Centre Eau Terre Environnement, 490 De La Couronne, Québec, QC G1K 9A9 (Canada); Bernatchez, Louis [Institut De Biologie Intégrative Et Des Systèmes (IBIS), Université Laval, Québec, QC G1V 0A6 (Canada); Campbell, Peter G.C.; Couture, Patrice [Institut National De La Recherche Scientifique (INRS), Centre Eau Terre Environnement, 490 De La Couronne, Québec, QC G1K 9A9 (Canada)

    2015-05-15

    Highlights: • Four-weeks exposure is sufficient to increase kidney metal levels in wild perch. • Cd and Cu affected indicators of retinoid metabolism and oxidative stress in fish. • Multi-level biological approaches are needed when assessing fish metal toxicology. • Changes at molecular level do not always mean changes at the functional level. • Wild juvenile perch may partly adjust to metal contamination by plastic responses. - Abstract: Despite recent progress achieved in elucidating the mechanisms underlying local adaptation to pollution, little is known about the evolutionary change that may be occurring at the molecular level. The goal of this study was to examine patterns of gene transcription and biochemical responses induced by metal accumulation in clean yellow perch (Perca flavescens) and metal depuration in contaminated fish in a mining and smelting region of Canada. Fish were collected from a reference lake (lake Opasatica) and a Cd, Cu and Zn contaminated lake (lake Dufault) located in the Rouyn-Noranda region (Qc, Canada) and caged for one or four weeks in their own lake or transplanted in the other lake. Free-ranging fish from the same lakes were also collected. Kidney Cd and Cu concentrations in clean fish caged in the contaminated lake increased with the time of exposure, but metal depuration did not occur in contaminated fish caged in the clean lake. After 4 weeks, the major retinoid metabolites analysed, the percentage of free dehydroretinol (dROH) and the retinol dehydrogenase-2 (rdh-2) transcription level in liver decreased in clean fish transplanted into the metal-contaminated lake, suggesting that metal exposure negatively impacted retinoid metabolism. However, we observed an increase in almost all of the retinoid parameters analysed in fish from the metal-impacted lake caged in the same lake, which we interpret as an adaptation response to higher ambient metal concentration. In support of this hypothesis, liver transcription levels

  3. Pressure load on keel bone and foot pads in perching laying hens in relation to perch design.

    Science.gov (United States)

    Pickel, T; Schrader, L; Scholz, B

    2011-04-01

    The provision of perches in housing systems for laying hens is meant to improve hens' welfare by allowing a more natural behavior repertoire. However, the use of perches is associated with welfare problems, such as keel bone deviations and foot pad lesions, that may possibly result from high mechanical pressure load during extended perching activities. The aim of this study was to analyze peak force and contact area of hens' keel bones and foot pads on solid test perches of square, round, and oval shape with 3 different diameters each (experiment 1) and on commercially used perches (round steel tube, 2 sizes of mushroom-shaped plastic, and flattened round plastic) together with 2 prototypes of soft, round polyurethane perches (experiment 2). Test perches were covered with a pressure sensor film and 36 laying hens (18 Lohmann Selected Leghorn, 18 Lohmann Brown) were consecutively placed on each perch in an experimental cage during nighttime. Peak force (N/cm(2)) and contact area (cm(2)) were measured while hens were sitting and standing on the different test perches. Pressure peaks on the keel bone were approximately 5 times higher compared with single foot pad. On square perches, keel bone peak force was lower (P keel bones in sitting hens and foot pads in standing hens (experiment 1). On prototype perches, peak force on the keel bone was lower and contact area was larger compared with all commercial perches tested (P keel bone and foot pad welfare problems in perching laying hens.

  4. Spotlight on fish: light pollution affects circadian rhythms of European perch but does not cause stress.

    Science.gov (United States)

    Brüning, Anika; Hölker, Franz; Franke, Steffen; Preuer, Torsten; Kloas, Werner

    2015-04-01

    Flora and fauna evolved under natural day and night cycles. However, natural light is now enhanced by artificial light at night, particularly in urban areas. This alteration of natural light environments during the night is hypothesised to alter biological rhythms in fish, by effecting night-time production of the hormone melatonin. Artificial light at night is also expected to increase the stress level of fish, resulting in higher cortisol production. In laboratory experiments, European perch (Perca fluviatilis) were exposed to four different light intensities during the night, 0 lx (control), 1 lx (potential light level in urban waters), 10 lx (typical street lighting at night) and 100 lx. Melatonin and cortisol concentrations were measured from water samples every 3h during a 24 hour period. This study revealed that the nocturnal increase in melatonin production was inhibited even at the lowest light level of 1 lx. However, cortisol levels did not differ between control and treatment illumination levels. We conclude that artificial light at night at very low intensities may disturb biological rhythms in fish since nocturnal light levels around 1 lx are already found in urban waters. However, enhanced stress induction could not be demonstrated. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Combined effects of temperature changes and metal contamination at different levels of biological organization in yellow perch

    Energy Technology Data Exchange (ETDEWEB)

    Grasset, Julie [Institut National de la Recherche Scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC G1K 9A9 (Canada); Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC G1V 0A6 (Canada); Ollivier, Élodie [Institut National de la Recherche Scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC G1K 9A9 (Canada); Bougas, Bérénice [Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC G1V 0A6 (Canada); Yannic, Glenn [Laboratoire d’Écologie Alpine, UMR CNRS 5553, Université de Savoie Mont Blanc, 73376 Le Bourget-du-lac (France); Campbell, Peter G.C. [Institut National de la Recherche Scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC G1K 9A9 (Canada); Bernatchez, Louis [Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC G1V 0A6 (Canada); Couture, Patrice, E-mail: patrice.couture@ete.inrs.ca [Institut National de la Recherche Scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC G1K 9A9 (Canada)

    2016-08-15

    Highlights: • Yellow perch were exposed to a combination of heat and metal (Cd or Ni) stress. • Kidney metal accumulation was greatly enhanced at higher temperatures. • Elevated temperatures negatively affected several indicators of condition and metabolic capacities. • Exposure to Ni stimulated gonad development. • Metal stress modified the normal response of antioxidant capacities and apoptosis to heat stress. - Abstract: In this study, we measured the effects of temperature (9 °C, 20 °C, and 28 °C), metal contamination (cadmium and nickel) and their interaction on yellow perch (Perca flavescens) using liver enzymatic and transcriptomic endpoints and biometric indices. Kidney metal concentrations increased with a rise of temperature. The biometric indices analysed (Fulton condition factor, pyloric cæca, hepatosomatic and gonadosomatic indices) generally decreased with an increase of temperature but not with metal contamination. At the enzymatic level, the activity of superoxide dismutase (SOD), involved in antioxidant response, was affected by both temperature and metal contamination, whereas the activity of glucose-6-phosphate dehydrogenase (G6PDH), involved in energy accumulation but also in antioxidant response, was only affected by metal exposure. The response of perch to the stressors at the transcriptional level differed from the metabolic response. In particular, the transcription level of the cco and g6pdh genes sharply decreased with increasing temperature, while the activities of the corresponding enzymes remained stable. The normal response of the transcription level of the apoptotic gene (diablo) to heat stress was also altered in metal-contaminated fish. The combination of metal and temperature stresses also modified the response of antioxidant metabolism induced by these stressors individually. This study contributes to a better understanding of the influences of natural stressors like temperature on biomarkers commonly used in

  6. Perch availability and ground cover: factors that may constitute ...

    African Journals Online (AJOL)

    1996-02-21

    Feb 21, 1996 ... than height because these birds hunt almost exclusively from perches, move regularly between them, and an increased number of .... of a perch-based hunter: (a) the bird searches a circular area under each perch; and ..... breeding birds. In: Natural selection and social behavior: recent research and new.

  7. Perch and Its Parasites as Heavy Metal Biomonitors in a Freshwater Environment: The Case Study of the Ružín Water Reservoir, Slovakia

    Directory of Open Access Journals (Sweden)

    Dana Miklisová

    2012-03-01

    Full Text Available Heavy metal concentrations were determined in 43 perches (Perca fluviatilis and in two of its most common parasites, the acanthocephalan Acanthocephalus lucii and the cestode Proteocephalus percae, collected in the period 2009–2010 from Ružín, a seriously polluted water reservoir in Slovakia. Samples of muscle, liver, kidney, brain, male and female reproductive organs and adipose tissue of fish and both parasites were analyzed for As, Cd, Cr, Cu, Hg, Mn, Ni, Pb and Zn, by ICP-MS. Mean concentrations of individual heavy metals in all fish samples decreased in the order zinc > copper > manganese > mercury > arsenic > chromium > cadmium > nickel > lead. Zinc was found to be the dominant element and its antagonistic interaction with copper was confirmed. The kidney was a key target organ receiving the highest mean concentrations of all analyzed metals, but some metals showed specific affinity for particular tissues. In terms of human health, concentration of Hg in fish muscle, which exceeded more than two-times its maximum level admitted in foodstuffs in European countries, is of great importance and should be taken into account. Bioaccumulation factors (C[parasite]/C[fish tissue] calculated for all elements indicated much higher detection skills of A. lucii and P. percae parasites than fish organs and hence, present results allow proposing both parasite models as useful tools to monitor aquatic environmental quality. Acanthocephalans, however, seem to be superior for heavy metal monitoring, also demonstrated under experimental conditions. Present results also indicate the decreasing heavy metal burden of the reservoir and its gradual recovery in the course of time.

  8. Depletion of the chloramine-T marker residue, para-toluenesulfonamide, from skin-on fillet tissue of hybrid striped bass, rainbow trout, and yellow perch

    Science.gov (United States)

    Meinertz, J.R.; Stehly, G.R.; Greseth, Shari L.; Gaikowski, M.P.; Gingerich, W.H.

    2004-01-01

    Waterborne exposure to n-sodium-n-chloro-p-toluenesulfonamide (chloramine-T) is an effective treatment for controlling fish mortalities caused by bacterial gill disease (BGD). Currently, data are being generated to gain United States Food and Drug Administration (FDA) approval for the use of chloramine-T in aquaculture. As part of the data required for an approval, depletion of the chloramine-T marker residue (para-toluenesulfonamide [p-TSA]) from the edible fillet tissue of exposed fish must be determined. Hybrid striped bass (Morone saxatilis??Morone chrysops; mean weight 357 g), rainbow trout (Oncorhynchus mykiss; mean weight 457 g), and yellow perch (Perca flavescens; mean weight 144 g) were exposed to 20 mg/l of chloramine-T for 60 min on 4 consecutive days (the most aggressive treatment expected for approved use in the United States). Groups of fish (n=15 or 19) were sampled immediately after the last treatment and periodically through 48 or 168 h after the treatment phase. Duplicate subsamples of skin-on fillet tissue from each fish were analyzed for p-TSA. Mean p-TSA concentrations in fillet tissue from fish sampled immediately after the last treatment were 142 ng/g (hybrid striped bass), 97 ng/g (rainbow trout), and 150 ng/g (yellow perch). Mean p-TSA concentrations at terminal sample times were 94 (168 h; hybrid striped bass), 74 (48 h; rainbow trout), and 35 ng/g (168 h; yellow perch). The half-lives of p-TSA in fillet tissue from fish near or at market size were 11.4 (hybrid striped bass), 4.3 (rainbow trout), and 3.2 days (yellow perch).

  9. 832-IJBCS-Article-Dr Temitope Jegede

    African Journals Online (AJOL)

    DR GATSING

    energy expenditure of juvenile Eurasian perch, Perca fluviatilis L. Aquaculture,. 272 (1-4): 312-318. Yasharian D, Coyle SD, Tidwell JH, Stilwil. WE. 2005. The effect of tank colouration on survival, Metamorphosis rate, growth and time to metamorphosis fresh water prawn (Macrobrachium rosenbergii) rearing. Aquaculture ...

  10. The Sources and Evolution of Eurasianism

    Directory of Open Access Journals (Sweden)

    Yulia Evgenievna Shulika

    2014-01-01

    Full Text Available In the recent time we have been witnessing the progressing Eurasian integration processes based on economic integration. In this context, we see the growing interest to Eurasianism that was approached not in terms of the “cold-head calculations”, but as civilizational, cultural, historical and formational determinism.

  11. Perch use by laying hens in a commercial aviary1

    Science.gov (United States)

    Campbell, D. L. M.; Makagon, M. M.; Swanson, J. C.; Siegford, J. M.

    2016-01-01

    Non-cage housing systems, such as the aviary, are being implemented by the laying hen industry, including in North America, in an attempt to improve the welfare of hens. Perches are a resource that is consistently included in aviaries. Hens are strongly motivated to perch, and perching can improve leg bone strength. However, hens may prefer elevated perches, particularly at night, and thus simply providing perches is not enough to improve welfare; they must be provided in a way that allows all hens to access them. Observations of laying hens using perches and ledges (flat, solid metal shelves to assist hens’ movement between tiers) in a commercial aviary revealed variation in where hens roosted within the tiered aviary enclosure across the flock cycle (peak, mid and end of lay; P < 0.001 for all age points). Hens most often preferred roosting in the highest enclosure levels, leading to crowding on upper perches and ledges while perch space remained available on lower levels. Restricted access to preferable perches may cause frustration in hens, leading to welfare issues. Hens roosted more on perches at peak lay than mid and end lay (P < 0.001) but roosted less on ledges at peak lay than mid and end lay (P < 0.001). Additionally, more hens roosted on both perches and ledges in the ‘dark’ observation period compared with the number of hens roosting during the ‘light’ observation period (P < 0.001). Further research should look at all structural elements within the system that are used by hens for roosting, such as edges of tiers and upper wire floors, to evaluate how changes in perching preferences across the lay cycle may correlate with system design and bird-based parameters. PMID:26994206

  12. The state in the Eurasian doctrine

    Directory of Open Access Journals (Sweden)

    S N Lebedev

    2016-12-01

    Full Text Available The article considers the role of the state in the Eurasian doctrine, one of the most distinctive and significant movements of the Russian sociological and political-philosophical thought abroad in the 1920-1930’s. The issues addressed by the Eurasians are still relevant under the current epoch of the new Russian statehood construction and to a certain extent are implemented in the contemporary political practice. According to the classical Eurasian doctrine, all nations of “Russia-Eurasia” are united by the “place of development” and constitute a single historical and socio-cultural world, which organically combines elements of the East and the West. The Eurasian doctrine of the state proclaims the idea of strong government and powerful state, which represents the interests of the people and maintains direct connections with its citizens by combining the law and justice principles with the norms of morality, welfare and conscience. The article examines the key Eurasian concept “ideocratic state” and the essential characteristics of the Eurasian concept of the state system, such as ideocracy, autarchy, idea-ruler, and ruling selection. The key state-forming concept is “Pan-Eurasian nationalism” interpreted by the Eurasians as an archetype of ideology, a basis of the national idea. The authors consider basic principles of the socio-economic structure of the Eurasian state, including active participation of the state in the economic life of the country, the coexistence of public and private properties. According to the Eurasian doctrine, the state-planned economy and the state regulation of culture form the foundations of autarchic states that protect the country from economic and humanitarian intervention. The authors come to the conclusion that Eurasian theory of the state can significantly enrich nowadays scientific theory and help to solve the tasks of modernization of the Russian society at the present stage for it takes

  13. The role of vision in perching and grasping for MAVs

    Science.gov (United States)

    Thomas, Justin; Loianno, Giuseppe; Daniilidis, Kostas; Kumar, Vijay

    2016-05-01

    In this work, we provide an overview of vision-based control for perching and grasping for Micro Aerial Vehicles. We investigate perching on at, inclined, or vertical surfaces as well as visual servoing techniques for quadrotors to enable autonomous perching by hanging from cylindrical structures using only a monocular camera and an appropriate gripper. The challenges of visual servoing are discussed, and we focus on the problems of relative pose estimation, control, and trajectory planning for maneuvering a robot with respect to an object of interest. Finally, we discuss future challenges to achieve fully autonomous perching and grasping in more realistic scenarios.

  14. Waterborne cadmium and nickel impact oxidative stress responses and retinoid metabolism in yellow perch

    Energy Technology Data Exchange (ETDEWEB)

    Defo, Michel A. [Institut national de la recherche scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, Québec G1K 9A9 (Canada); Bernatchez, Louis [Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec G1V 0A6 (Canada); Campbell, Peter G.C. [Institut national de la recherche scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, Québec G1K 9A9 (Canada); Couture, Patrice, E-mail: patrice.couture@ete.inrs.ca [Institut national de la recherche scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, Québec G1K 9A9 (Canada)

    2014-09-15

    Highlights: • Cd and Ni affected indicators of retinoid metabolism and oxidative stress in fish. • Liver rdh-2 transcription levels increase in fish exposed to waterborne Cd. • Liver REH and LdRAT activities increase with increasing kidney Cd concentration. • Changes at molecular levels do not always mean changes at the functional levels. • Multi-level biological approaches are needed when assessing fish metal toxicology. - Abstract: In this experiment, we studied the transcriptional and functional (enzymatic) responses of yellow perch (Perca flavescens) to metal stress, with a focus on oxidative stress and vitamin A metabolism. Juvenile yellow perch were exposed to two environmentally relevant concentrations of waterborne cadmium (Cd) and nickel (Ni) for a period of 6 weeks. Kidney Cd and Ni bioaccumulation significantly increased with increasing metal exposure. The major retinoid metabolites analyzed in liver and muscle decreased with metal exposure except at high Cd exposure where no variation was reported in liver. A decrease in free plasma dehydroretinol was also observed with metal exposure. In the liver of Cd-exposed fish, both epidermal retinol dehydrogenase 2 transcription level and corresponding enzyme activities retinyl ester hydrolase and lecithin dehydroretinyl acyl transferase increased. In contrast, muscle epidermal retinol dehydrogenase 2 transcription level decreased with Cd exposure. Among antioxidant defences, liver transcription levels of catalase, microsomal glutathione-S-transferase-3 and glucose-6-phosphate dehydrogenase were generally enhanced in Cd-exposed fish and this up-regulation was accompanied by an increase in the activities of corresponding enzymes, except for microsomal glutathione-S-transferase. No consistent pattern in antioxidant defence responses was observed between molecular and biochemical response when fish were exposed to Ni, suggesting a non-synchronous response of antioxidant defence in fish exposed to

  15. MOLDOVA: MISSED ADVANTAGES OF EURASIAN INTEGRATION

    Directory of Open Access Journals (Sweden)

    Ludmila Vasiljevna Fokina

    2015-01-01

    Full Text Available The article is devoted to potentially missed advantages of Eurasian integration (EAEU for Moldova. Special attention is given to the branches in which the country could get evident advantages including agriculture, power engineering, external trade ties with the EAEU countries. Possible positive effects of Eurasian integration in solution of the Transnistrian problem, in the sphere of labour migration and other fields are also shown.

  16. Enhancement of anaerobic digestion of Nile perch fish processing ...

    African Journals Online (AJOL)

    In East Africa, Nile perch processing into fish fillets for export generates large proportions of both solid and liquid fish wastes. These wastes are improperly utilized and/or disposed off untreated leading to environmental pollution problems. On the other hand, Nile perch fish processing wastewater (FPW) contains high ...

  17. A Kinetic Study of Accumulation and Elimination of Microcystin-LR in Yellow Perch (Perca Flavescens) Tissue and Implications for Human Fish Consumption

    OpenAIRE

    Kashian, Donna R.; Peter Landrum; Duane Gossiaux; Julianne Dyble; Steven Pothoven

    2011-01-01

    Fish consumption is a potential route of human exposure to the hepatotoxic microcystins, especially in lakes and reservoirs that routinely experience significant toxic Microcystis blooms. Understanding the rates of uptake and elimination for microcystins as well as the transfer efficiency into tissues of consumers are important for determining the potential for microcystins to be transferred up the food web and for predicting potential human health impacts. The main objective of this work was...

  18. Experimental analysis of perching in the European starling (Sturnus vulgaris: Passeriformes; Passeres), and the automatic perching mechanism of birds.

    Science.gov (United States)

    Galton, Peter M; Shepherd, Jeffrey D

    2012-04-01

    The avian automatic perching mechanism (APM) involves the automatic digital flexor mechanism (ADFM) and the digital tendon-locking mechanism (DTLM). When birds squat on a perch to sleep, the increased tendon travel distance due to flexion of the knee and ankle supposedly causes the toes to grip the perch (ADFM) and engage the DTLM so perching while sleeping involves no muscular effort. However, the knees and ankles of sleeping European starlings (Sturnus vulgaris) are only slightly flexed and, except for occasional balancing adjustments, the distal two-thirds of the toes are not flexed to grip a 6-mm-diameter perch. The cranial ankle angle (CAA) is ∼120° and the foot forms an inverted "U" that, with the mostly unflexed toes, provides a saddle-like structure so the bird balances its weight over the central pad of the foot (during day weight further back and digits actively grasp perch). In the region of the pad, the tendon sheath of many birds is unribbed, or only very slightly so, and it is always separated from the tendon of the M. flexor digitorum longus by tendons of the other toe flexor muscles. Passive leg flexion produces no toe flexion in anesthetized Starlings and only after 15-20 min, at the onset of rigor mortis, in freshly sacrificed Starlings. Anesthetized Starlings could not remain perched upon becoming unconscious (ADFM, DTLM intact). Birds whose digital flexor tendons were severed or the locking mechanism eliminated surgically (no ADFM or DTLM), so without ability to flex their toes, slept on the perch in a manner similar to unoperated Starlings (except CAA ∼90°-110°). Consequently, there is no APM or ADFM and the DTLM, although involved in lots of other activities, only acts in perching with active contraction of the digital flexor muscles. © 2012 WILEY PERIODICALS, INC.

  19. Population morphological variation of the Nile perch (Lates niloticus ...

    African Journals Online (AJOL)

    use

    3264. The existence of 2 morphs agrees with earlier taxonomists (Harrison, 1991; Ribbink, 1987; Bwathondi, 1985; Holden, 1967) who proposed that Nile perch exists in two populations – a bigger shallow water dwelling morph and a.

  20. Flavonoid variation in Eurasian Sedum and Sempervivum

    NARCIS (Netherlands)

    Stevens, J.F; 't Hart, H; Elema, E.T; Bolck, A

    Flavonoids from vegetative parts of 29 species of Eurasian Sedum, Sedum meyeri-johannis from central East Africa, 34 species of Sempervivum, and Jovibarba heuffelii have been identified after acid hydrolysis. Ten flavonoid aglycones were detected, i.e. kaempferol, herbacetin, sexangularetin,

  1. To the Question of the Eurasian Integration

    Directory of Open Access Journals (Sweden)

    G R Akhmedova

    2009-06-01

    Full Text Available In this article the author analyses the main directions and perspectives of cooperation among member countries of CIS in the framework of Eurasian Organization. The potential of this cooperation is great, but realization of this potential demands considerable efforts from the participants of the process.

  2. The Eurasian Knowledge-based Economy Formation in the Eurasian Economic Union Area

    Directory of Open Access Journals (Sweden)

    Elena Vladimirovna Sapir

    2015-12-01

    Full Text Available Currently, there is an intensification of integration processes in the global economy. Integration is an effective tool to overcome the modern challenges and threats. However, for the effective countries and regions integration in the global economy it requires the active development of innovation processes along with the integration processes. On the 29th of May, 2014 in Astana the Treaty establishing the Eurasian Economic Union was signed by the Presidents of Russia, Belarus and Kazakhstan, and entered into force on the First of January 2015. In this regard, the article analyzes the foundations of the knowledge economy concept. Moreover, it researches the emergence of the Eurasian knowledge economy in several stages using the statistical data and the index method. The article suggests that the Eurasian Economic Union has a significant potential for the development of the Eurasian regional knowledge economy and proposes a number of measures for successful formation of it. International legal formalization of the process can become Eurasian Convention in the field of the knowledge economy. This article expands the understanding of the prospects of integration and innovation processes within the Eurasian Economic Union.

  3. Numerical modeling of perched water under Yucca Mountain, Nevada

    Science.gov (United States)

    Hinds, J.J.; Ge, S.; Fridrich, C.J.

    1999-01-01

    The presence of perched water near the potential high-level nuclear waste repository area at Yucca Mountain, Nevada, has important implications for waste isolation. Perched water occurs because of sharp contrasts in rock properties, in particular between the strongly fractured repository host rock (the Topopah Spring welded tuff) and the immediately underlying vitrophyric (glassy) subunit, in which fractures are sealed by clays that were formed by alteration of the volcanic glass. The vitrophyre acts as a vertical barrier to unsaturated flow throughout much of the potential repository area. Geochemical analyses (Yang et al. 1996) indicate that perched water is relatively young, perhaps younger than 10,000 years. Given the low permeability of the rock matrix, fractures and perhaps fault zones must play a crucial role in unsaturated flow. The geologic setting of the major perched water bodies under Yucca Mountain suggests that faults commonly form barriers to lateral flow at the level of the repository horizon, but may also form important pathways for vertical infiltration from the repository horizon down to the water table. Using the numerical code UNSAT2, two factors believed to influence the perched water system at Yucca Mountain, climate and fault-zone permeability, are explored. The two-dimensional model predicts that the volume of water held within the perched water system may greatly increase under wetter climatic conditions, and that perched water bodies may drain to the water table along fault zones. Modeling results also show fault flow to be significantly attenuated in the Paintbrush Tuff non-welded hydrogeologic unit.

  4. FOREIGN POLICY OF EUROPEAN UNION: EURASIAN AGENDA

    Directory of Open Access Journals (Sweden)

    Oleksiy KANDYUK

    2016-10-01

    Full Text Available EU’s influence at so-called post-Soviet space gradually increases and becomes a significant factor of regional policy. Today we can already speak of the European Union as a full participant in the political processes occurring in the post-Soviet and broader – Eurasian area. Foreign policy of EU is evolving under impact of reasons stemming from both structural and political context and from external geopolitical trends. At the same time, challenges in the geopolitical environment in Europe today require the EU to develop new conceptual approaches helping to deal with the problems of relations with its eastern neighbours and the Russian impact. Only the development of a new Eurasian agenda could help to improve European eastern policy, consolidate the position of EU as a geopolitical actor in this region and foster Europeanization and integration of neighbour countries.

  5. Development of a bio-inspired UAV perching system

    Science.gov (United States)

    Xie, Pu

    Although technologies of unmanned aerial vehicles (UAVs) including micro air vehicles (MAVs) have been greatly advanced in the recent years, it is still very difficult for a UAV to perform some very challenging tasks such as perching to any desired spot reliably and agilely like a bird. Unlike the UAVs, the biological control mechanism of birds has been optimized through millions of year evolution and hence, they can perform many extremely maneuverability tasks, such as perching or grasping accurately and robustly. Therefore, we have good reason to learn from the nature in order to significantly improve the capabilities of UAVs. The development of a UAV perching system is becoming feasible, especially after a lot of research contributions in ornithology which involve the analysis of the bird's functionalities. Meanwhile, as technology advances in many engineering fields, such as airframes, propulsion, sensors, batteries, micro-electromechanical-system (MEMS), and UAV technology is also advancing rapidly. All of these research efforts in ornithology and the fast growing development technologies in UAV applications are motivating further interests and development in the area of UAV perching and grasping research. During the last decade, the research contributions about UAV perching and grasping were mainly based on fixed-wing, flapping-wing, and rotorcraft UAVs. However, most of the current researches in UAV systems with perching and grasping capability are focusing on either active (powered) grasping and perching or passive (unpowered) perching. Although birds do have both active and passive perching capabilities depending on their needs, there is no UAV perching system with both capabilities. In this project, we focused on filling this gap. Inspired by the anatomy analysis of bird legs and feet, a novel perching system has been developed to implement the bionics action for both active grasping and passive perching. In addition, for developing a robust and

  6. Orthopoxvirus DNA in Eurasian Lynx, Sweden

    OpenAIRE

    Tryland, Morten; Okeke, Malachy Ifeanyi; Hård af Segerstad, Carl; Mörner, Torsten; Traavik, Ingemar Terje; Ryser-Degiorgis, Marie-Pierre

    2011-01-01

    Cowpox virus, which has been used to protect humans against smallpox but may cause severe disease in immunocompromised persons, has reemerged in humans, domestic cats, and other animal species in Europe. Orthopoxvirus (OPV) DNA was detected in tissues (lung, kidney, spleen) in 24 (9%) of 263 free-ranging Eurasian lynx (Lynx lynx) from Sweden. Thymidine kinase gene amplicon sequences (339 bp) from 21 lynx were all identical to those from cowpox virus isolated from a person in Norway a...

  7. Atmospheric controls on Eurasian snow extent

    Science.gov (United States)

    Clark, Martyn P.; Serreze, Mark C.; Robinson, David A.

    1999-01-01

    Composite analyses, based on weekly snow-cover charts, temperature, sea level pressure, cyclone tracks and a rotated PCA of daily filtered 700 hPa geopotential height are used to examine relationships between the dominant modes of low-frequency atmospheric variability and mid-winter snow extent over the Eurasian continent. Two of the circulation modes examined have been identified previously and represent the North Atlantic Oscillation (NAO) and the Eurasian Type 1 (EU1) pattern. A third, termed the Siberian pattern (SIB), has not been identified previously, and describes variability in 700 hPa height over central Asia and southern Siberia. The most coherent snow-cover signals occur in the transient snow regions over Europe and south-western Asia, where variations in snow extent are largely controlled by temperature. Snow signals in east Asia are difficult to explain, but appear to be primarily determined by the availability of precipitation. For the NAO, snow-cover signals are largely restricted to central Europe. This result is initially surprising, as the NAO is associated with large temperature anomalies over a large part of the Eurasian continent. However, east of the Ural Mountains temperature anomalies in NAO extremes are confined to northern regions where mean temperatures are well below freezing, and air temperatures have little influence on snow extent. In extremes of the EU1 and SIB patterns, significant snow-cover signals are found in south-western Asia, where variability in the amplitude of the Eurasian wave train results in large differences in air temperature and cyclone activity over the transient snow regions. No coherent snow-cover signals are associated with extremes of the Siberian High.

  8. Evaluating fishery rehabilitation under uncertainty: A bioeconomic analysis of quota management for the Green Bay yellow perch fishery

    Science.gov (United States)

    Johnson, B.L.; Milliman, S.R.; Bishop, R.C.; Kitchell, J.F.

    1992-01-01

    The fishery for yellow perch Perca flavescens in Green Bay, Lake Michigan, is currently operating under a rehabilitation plan based on a commercial harvest quota. We developed a bioeconomic computer model that included links between population density and growth, recruitment, and fishing effort for this fishery. Random variability was included in the stock-recruitment relation and in a simulated population assessment. We used the model in an adaptive management framework to evaluate the effects of the rehabilitation plan on both commercial and sport fisheries and to search for ways to improve the plan. Results indicate that the current quota policy is a member of a set of policies that would meet most management goals and increase total value of the fishery. Sensitivity analyses indicate that this conclusion is robust over a wide range of biological conditions. We predict that commercial fishers will lose money relative to the baseline condition, but they may receive other benefits from the elimination of the common-property nature of the fishery. The prospect exists for managing variability in harvest and stock size and for maximizing economic returns in the fishery, but more information is required, primarily on sportfishing effort dynamics and angler preferences. Stock-recruitment relations, density dependence of growth, and dynamics of sportfishing effort are the primary sources of uncertainty limiting the precision of our predictions. The current quota policy is about as good as other policies at reducing this uncertainty and appears, overall, to be one of the best choices for this fishery. The analytical techniques used in this study were primarily simple, heuristic approaches that could be easily transferred to other studies.

  9. Perch use by broiler breeders and its implication on health and production.

    Science.gov (United States)

    Gebhardt-Henrich, S G; Toscano, M J; Würbel, H

    2017-10-01

    Broiler breeders are commonly kept without perches, although perching has been shown to be a high-priority behavior in laying hens. We studied whether broiler breeders used elevated perches of different lengths during the night and how access to perches affected health and production. Using the Ross 308 hybrid, pens offering 4 different perch spaces per bird (5, 10, 14, and 20 cm) in a cross-over design were compared with pens without perches. The number of birds on perches at midnight were recorded 7 times during production. Prevalence of keel bone fractures, breast blisters, pododermatitis, and plumage quality of hens was assessed at 45 wk, and production was monitored daily. To determine subsequent effects on offspring, chicks from hens with and without perches were reared and their growth rate was assessed. Analysis found more broiler breeders perched at night when 14 cm perch length per bird was provided than with less available perch length (P = 0.0005), but there was no difference between 14 and 20 cm per bird. Perch use declined with age from about 50 to 20% (P growth of chicks was not affected by the parent treatment. In conclusion, our results suggest that perches were chosen for roosting by broiler breeders depending on their age and did not impair production. © 2017 Poultry Science Association Inc.

  10. Scientific Opinion on welfare aspects of the use of perches for laying hens

    National Research Council Canada - National Science Library

    Berg, Charlotte; Vågsholm, Ivar; Ducrot, Christian

    2015-01-01

    This opinion investigated the use of perches for laying hens in cage and non‐cage systems. It is based on various activities reviewing the effects of perch height and design on hen health and welfare...

  11. Putin’s Third Term: The Triumph of Eurasianism?

    Directory of Open Access Journals (Sweden)

    Paul Pryce

    2013-03-01

    Full Text Available In the midst of the Russian Federation's 2012 presidential election, Vladimir Putin expressed his support for the establishment of a functioning Eurasian Union by 2015. This article attempts to demonstrate that this Eurasian push, taken in context together with a number of other policies and programs pursued by Putin and Dmitri Medvedev, reflects a shift in Russian identity politics towards neo-Eurasianism. In doing so, the potential weaknesses of neo-Eurasianism as an identity framework for the whole of Russian society will be highlighted, indicating that the further centralization of political authority with the core (Moscow will only exacerbate grievances in the regions of the periphery.

  12. EURASIAN CUSTOMS UNION – ANALYSES AND PERSPECTIVES

    Directory of Open Access Journals (Sweden)

    Brindusa-Nicoleta PINCU

    2014-10-01

    Full Text Available In the era of Globalization the process of integration is speeded and taken to a different level. After the EU model, we are facing now with different entities trying to copy this model and adjusting it to their needs. Such a project is the Eurasian Customs Union, a project which has only recently come into being. The present paper will analyze the driven forces behind this and its capacity to fully function as a customs union before the year 2020- the time limit set by the Russian President Vladimir Putin.

  13. Salmonella and Vibrio cholerae in Nile perch ( Lates niloticus ...

    African Journals Online (AJOL)

    The Nile perch (Lates niloticus) industry in East Africa has suffered severe economic losses in the last few years due to failure to comply with the microbiological standards of European Union (E.U). Fresh and frozen products have been suspected to be contaminated with Salmonella and Vibrio cholerae. This has led to a ...

  14. Bird Perches Increase Forest Seeds on Puerto Rican Landslides.

    Science.gov (United States)

    Aaron B. Shiels; Lawrence R. Walker

    2003-01-01

    Landslides result in the loss of vertical vegetative structure, soil nutrients, and the soil seed bank. These losses impede timely recovery of tropical forest communities. In this study we added bird perches to six Puerto Rican landslides with three types of surfaces (bare, climbing fern, grass) in an effort to facilitate inputs of forest seeds through bird dispersal...

  15. Fish protein fingerprint in whole muscle samples of yellow perch ...

    African Journals Online (AJOL)

    However, the role of genes supporting the cellular and molecular mechanisms responsible for fish was to compare whole muscle proteomic profiles of large versus small growth yellow perch and identify the proteins associated with fish growth or size. Seven samples of large fish (16 - 18g) and seven samples of small fish (3 ...

  16. Pan Eurasian Experiment (PEEX): a new research initiative focused on the Northern Pan-Eurasian Region

    Science.gov (United States)

    Petäjä, Tuukka; Lappalainen, Hanna; Zaytseva, Nina; Shvidenko, Anatoli; Kujansuu, Joni; Kerminen, Veli-Matti; Viisanen, Yrjö; Kotlyakov, Vladimir; Kasimov, Nikolai; Bondur, Valery; Matvienko, Gennadi; Zilitinkevich, Sergej; Kulmala, Markku

    2014-05-01

    The increasing human activities are changing the environment and the humanity is we are pushing the safe boundaries of the globe. It is of utmost importance to gauge with a comprehensive research program on the current status of the environment, particularly in the most vulnerable locations. Pan-Eurasian Experiment (PEEX) is a new multidisciplinary research approach aiming at resolving the major uncertainties in the Earth system science and global sustainability questions in the Arctic and boreal Pan-Eurasian regions. The PEEX program aims (i) to understand the Earth system and the influence of environmental and societal changes in pristine and industrialized Pan-Eurasian environments, (ii) to establish and sustain long-term, continuous and comprehensive ground-based airborne and seaborne research infrastructures, and to utilize satellite data and multi-scale model frameworks, (iii) to contribute to regional climate scenarios in the northern Pan-Eurasia and determine the relevant factors and interactions influencing human and societal wellbeing (iv) to promote the dissemination of PEEX scientific results and strategies in scientific and stake-holder communities and policy making, (v) to educate the next generation of multidisciplinary global change experts and scientists, and (vi) to increase the public awareness of climate change impacts in the Pan-Eurasian region. The development of PEEX research infrastructure will be one of the first activities of PEEX. PEEX will find synergies with the major European land-atmosphere observation infrastructures such as ICOS a research infrastructure to decipher the greenhouse gas balance of Europe and adjacent regions, ACTRIS (Aerosols, Clouds, and Trace gases Research InfraStructure Network-project), and ANAEE (The experimentation in terrestrial ecosystem research) networks and with the flag ship stations like the SMEARs (Station for Measuring Ecosystem-Atmosphere Relations) when design, re-organizing and networking existing

  17. Demonstrations of bio-inspired perching landing gear for UAVs

    Science.gov (United States)

    Tieu, Mindy; Michael, Duncan M.; Pflueger, Jeffery B.; Sethi, Manik S.; Shimazu, Kelli N.; Anthony, Tatiana M.; Lee, Christopher L.

    2016-04-01

    Results are presented which demonstrate the feasibility and performance of two concepts of biologically-inspired landing-gear systems that enable bird-sized, unmanned aerial vehicles (UAV's) to land, perch, and take-off from branchlike structures and/or ledges. The first concept follows the anatomy of birds that can grasp ahold of a branch and perch as tendons in their legs are tensioned. This design involves a gravity-activated, cable-driven, underactuated, graspingfoot mechanism. As the UAV lands, its weight collapses a four-bar linkage pulling a cable which curls two opposing, multi-segmented feet to grasp the landing target. Each foot is a single, compliant mechanism fabricated by simultaneouly 3D-printing a flexible thermo-plastic and a stiffer ABS plastic. The design is optimized to grasp structures over a range of shapes and sizes. Quasi-static and flight tests of this landing gear affixed to RC rotorcraft (24 cm to 550 cm in diameter) demonstrate that the aircraft can land, perch, and take-off from a tree branch, rectangular wood board, PVC pipe, metal hand rail, chair armrest, and in addition, a stone wall ledge. Stability tests show that perching is maintained under base and wind disturbances. The second design concept, inspired by roosting bats, is a two-material, 3D-printed hooking mechanism that enables the UAV to stably suspend itself from a wire or small-diameter branch. The design balances structural stiffness for support and flexibility for the perching process. A flight-test demonstrates the attaching and dis-engaging of a small, RC quadcopter from a suspended line.

  18. Ultraviolet radiation influences perch selection by a neotropical poison-dart frog.

    Directory of Open Access Journals (Sweden)

    Lee B Kats

    Full Text Available Ambient ultraviolet-B radiation can harm amphibian eggs, larvae and adults. However, some amphibians avoid UV-B radiation when given the opportunity. The strawberry poison dart frog, Oophaga pumilio, is diurnal and males vocalize throughout the day in light gaps under forest canopies that expose them to solar radiation. Previous studies have demonstrated that males calling from high perches are more successful at mating than those at lower perches. We investigated whether frogs at higher perches receive more ultraviolet-B than those calling from lower perches. We also investigated whether frogs on perches receiving relatively low ultraviolet-B levels maintained their positions for longer compared to individuals calling from perches receiving higher levels of ultraviolet-B. Finally, since it has been hypothesized that some animals utilize levels of UV-A as a visual cue to avoid UV-B damage, we artificially elevated ultraviolet-A levels to examine whether males exposed to artificially elevated ultraviolet-A abandoned their perches sooner compared to males exposed to visible light. We found that frogs called from perches receiving low ultraviolet-B regardless of perch height, and that frogs maintain their positions longer on perches receiving low ultraviolet-B compared to perches receiving even slightly higher ultraviolet-B levels. Exposing the frogs to artificially elevated levels of ultraviolet-A radiation caused males to move off of their perches faster than when they were exposed to a control light source. These experiments suggest that ultraviolet radiation plays an important role in frog behavior related to perch selection, even in rainforests where much of the solar radiation is shielded by the forest canopy.

  19. Orthopoxvirus DNA in Eurasian lynx, Sweden.

    Science.gov (United States)

    Tryland, Morten; Okeke, Malachy Ifeanyi; Af Segerstad, Carl Hård; Mörner, Torsten; Traavik, Terje; Ryser-Degiorgis, Marie Pierre

    2011-04-01

    Cowpox virus, which has been used to protect humans against smallpox but may cause severe disease in immunocompromised persons, has reemerged in humans, domestic cats, and other animal species in Europe. Orthopoxvirus (OPV) DNA was detected in tissues (lung, kidney, spleen) in 24 (9%) of 263 free-ranging Eurasian lynx (Lynx lynx) from Sweden. Thymidine kinase gene amplicon sequences (339 bp) from 21 lynx were all identical to those from cowpox virus isolated from a person in Norway and phylogenetically closer to monkeypox virus than to vaccinia virus and isolates from 2 persons with cowpox virus in Sweden. Prevalence was higher among animals from regions with dense, rather than rural, human populations. Lynx are probably exposed to OPV through predation on small mammal reservoir species. We conclude that OPV is widely distributed in Sweden and may represent a threat to humans. Further studies are needed to verify whether this lynx OPV is cowpox virus.

  20. Northern Eurasian Heat Waves and Droughts

    Science.gov (United States)

    Schubert, Siegfried; Wang, Hailan; Koster, Randal; Suarez, Max; Groisman, Pavel

    2013-01-01

    This article reviews our understanding of the characteristics and causes of northern Eurasian summertime heat waves and droughts. Additional insights into the nature of temperature and precipitation variability in Eurasia on monthly to decadal time scales and into the causes and predictability of the most extreme events are gained from the latest generation of reanalyses and from supplemental simulations with the NASA GEOS-5 AGCM. Key new results are: 1) the identification of the important role of summertime stationary Rossby waves in the development of the leading patterns of monthly Eurasian surface temperature and precipitation variability (including the development of extreme events such as the 2010 Russian heat wave), 2) an assessment of the mean temperature and precipitation changes that have occurred over northern Eurasia in the last three decades and their connections to decadal variability and global trends in SST, and 3) the quantification (via a case study) of the predictability of the most extreme simulated heat wave/drought events, with some focus on the role of soil moisture in the development and maintenance of such events. A literature survey indicates a general consensus that the future holds an enhanced probability of heat waves across northern Eurasia, while there is less agreement regarding future drought, reflecting a greater uncertainty in soil moisture and precipitation projections. Substantial uncertainties remain in our understanding of heat waves and drought, including the nature of the interactions between the short-term atmospheric variability associated with such extremes and the longer-term variability and trends associated with soil moisture feedbacks, SST anomalies, and an overall warming world.

  1. Nutritional composition and shelflife of the lake victoria nile perch ...

    African Journals Online (AJOL)

    The %FFA increased from 1.9 to 2.7% at the point of rejection, while the TVC and hydrogen sulphide producing bacterial counts increased from 6.6 log cfu/g to 8.0 log cfu/g and 4.3 log cfu/g to 7.3 log cfu/g, respectively. The study established that the ungutted iced Nile perch handled under normal conditions in this fishery ...

  2. Ecology and population status of trout-perch (Percopsis omiscomaycus) in western Lake Erie

    Science.gov (United States)

    Kocovsky, Patrick; Stoneman, Andrea T.; Kraus, Richard T.

    2014-01-01

    Trout-perch Percopsis omiscomaycus is among the most abundant benthic species in Lake Erie, but comparatively little is known about its ecology. Although others have conducted extensive studies on trout-perch ecology, those efforts predated invasions of white perch Morone americana, Dreissena spp., Bythotrephes longimanus and round goby Neogobius melanostomus, suggesting the need to revisit past work. Trout-perch were sampled with bottom trawls at 56 sites during June and September 2010. We examined diets, fecundity, average annual mortality, sex ratio, and long-term population trends at sites sampled since 1961. Trout-perch abundance fluctuated periodically, with distinct shorter- (4-year) and longer-term (over period of 50 years) fluctuations. Males had higher average annual mortality than females. Both sexes were equally abundant at age 0, but females outnumbered males 4:1 by age 2. Diets of trout-perch were dominated by macroinvertebrates, particularly chironomids and Hexagenia sp. Size distributions of trout-perch eggs varied widely and exhibited multiple modes indicative of protracted batch spawning. A review of the few other studies of trout-perch revealed periodic fluctuations in sex ratio of adults, which in light of our evidence of periodicity in abundance suggests the potential for sex-ratio-mediated intrinsic population regulation. Despite the introduction of numerous invasive species in Lake Erie, trout-perch remain one of the most abundant benthic invertivores and the population is relatively stable.

  3. Regional energy projects in the Eurasian Area

    Directory of Open Access Journals (Sweden)

    Vesić Dobrica

    2012-03-01

    Full Text Available The Eurasian area has a very rich energy reserves, and is characterized by a complex network of relationships between major suppliers and consumers. The central place in this area has Russia as a country richest in energy resources in Eurasia. Beside her, the European Union is the largest economic and political grouping in the world, and a huge consumer of energy. The dynamic development of Chinese economy requires more energy imports by China. Dependence of the European Union and China on imported energy is high and will grow in the future. Russia is the world's dominant natural gas producer and one of the two largest oil producers in the world. Russia is the largest natural gas supplier of the EU and a significant oil and natural gas supplier of China. Energy projects in Eurasia are the result of the need to strengthen the stability of energy supplies, efforts to diversify sources of supply, and the geographic redistribution of Russian oil and gas exports. Although the interests of the main actors often do not agree, the reasons of energy security affect the development of joint energy projects.

  4. The diet of reservoir perch before, during and after establishment of non-native tubenose goby

    Czech Academy of Sciences Publication Activity Database

    Všetičková, Lucie; Mikl, Libor; Adámek, Zdeněk; Prášek, Václav; Roche, Kevin Francis; Jurajda, Pavel

    2018-01-01

    Roč. 419, č. 419 (2018), č. článku 4. ISSN 1961-9502 R&D Projects: GA ČR(CZ) GBP505/12/G112 Institutional support: RVO:68081766 Keywords : dietary shift * food preference * Gobiidae * invasive species * Perca fluviatilis * piscivore diet Subject RIV: EG - Zoology Impact factor: 1.217, year: 2016

  5. Dynamics and Control of Three-Dimensional Perching Maneuver under Dynamic Stall Influence

    Science.gov (United States)

    Feroskhan, Mir Alikhan Bin Mohammad

    Perching is a type of aggressive maneuver performed by the class 'Aves' species to attain precision point landing with a generally short landing distance. Perching capability is desirable on unmanned aerial vehicles (UAVs) due to its efficient deceleration process that potentially expands the functionality and flight envelope of the aircraft. This dissertation extends the previous works on perching, which is mostly limited to two-dimensional (2D) cases, to its state-of-the-art threedimensional (3D) variety. This dissertation presents the aerodynamic modeling and optimization framework adopted to generate unprecedented variants of the 3D perching maneuver that include the sideslip perching trajectory, which ameliorates the existing 2D perching concept by eliminating the undesirable undershoot and reliance on gravity. The sideslip perching technique methodically utilizes the lateral and longitudinal drag mechanisms through consecutive phases of yawing and pitching-up motion. Since perching maneuver involves high rates of change in the angles of attack and large turn rates, introduction of three internal variables thus becomes necessary for addressing the influence of dynamic stall delay on the UAV's transient post-stall behavior. These variables are then integrated into a static nonlinear aerodynamic model, developed using empirical and analytical methods, and into an optimization framework that generates a trajectory of sideslip perching maneuver, acquiring over 70% velocity reduction. An impact study of the dynamic stall influence on the optimal perching trajectories suggests that consideration of dynamic stall delay is essential due to the significant discrepancies in the corresponding control inputs required. A comparative study between 2D and 3D perching is also conducted to examine the different drag mechanisms employed by 2D and 3D perching respectively. 3D perching is presented as a more efficient deceleration technique with respect to spatial costs and

  6. Are high perches in the blackcap Sylvia atricapilla song or listening posts? A sound transmission study

    DEFF Research Database (Denmark)

    Mathevon, Nicolas; Dabelsteen, Torben; Blumenrath, Sandra Helene

    2005-01-01

    Birds often sing from high perches referred to as song posts. However, birds also listen and keep a lookout from these perches. We used a sound transmission experiment to investigate the changes for receiving and sending conditions that a territorial songbird may experience by moving upwards...

  7. Distribution of Nile perch Lates niloticus in southern Lake Victoria is ...

    African Journals Online (AJOL)

    Although Nile perch Lates niloticus is assumed to be sensitive to low oxygen concentrations, it was found in deep water in Lake Victoria, where oxygen depletion is common during the rainy season. Since factors determining Nile perch distribution are not well understood its spatial distribution in the Mwanza Gulf of Lake ...

  8. Nile perch and the transformation of Lake Victoria | Taabu-Munyaho ...

    African Journals Online (AJOL)

    The sudden eutrophication of the lake was attributed to Nile perch, but evidence of eutrophication from 1950 onwards led some researchers to conclude that it was the result of climatic changes. We conclude that the haplochromine destruction disrupted the complex food webs that existed prior to the upsurge of Nile perch.

  9. Communication in the Third Dimension: Song Perch Height of Rivals Affects Singing Response in Nightingales

    NARCIS (Netherlands)

    Sprau, P.; Roth, T.; Naguib, M.; Amrhein, V.

    2012-01-01

    Many animals use long-range signals to compete over mates and resources. Optimal transmission can be achieved by choosing efficient signals, or by choosing adequate signalling perches and song posts. High signalling perches benefit sound transmission and reception, but may be more risky due to

  10. Eurasian Union on the Viewpoint of China: Geopolitical Perspective

    Directory of Open Access Journals (Sweden)

    Guo Cheng

    2015-12-01

    Full Text Available This article is about geopolitical strategic analyze of Russian President Vladimir Putin’s “Eurasian Union” strategy from Chinese viewpoint. The article describes historical background of Eurasian Union, its geopolitical purposes, achievements and weakness, particularly from China's national strategic design and stance of Central Asia in Eurasian Continent. The geopolitical analysis of possibility for Sino-Russian Alliance and realistic difficulties of it are provided. Different point of Chinese experts on Russia-West relations are given. Some of them believe that he Warsaw Pact and the Cold War revival in the CIS, its purpose is to play as geopolitical blunders against the Western countries under the leadership of NATO, IMF and the United States. While others, take into consideration the US-Russian Strategic Arms Reduction Treaty, and Russia’s actively participation in the former Group of Eight, accession to WTO and other initiatives that indicates the current Moscow is not the Soviet Union, and does not exclude cooperation with existing international system dominated by the Western world. And finally, China's own Eurasian strategy design is represented, especially China’s foreign policy options on Central Asia as solutions to some current existing geopolitical differences between China and Russia’s own Eurasian Strategy in order to achieve mutual win-set goal.

  11. Effects of stocking density, light and perches on broiler growth.

    Science.gov (United States)

    Velo, Ramón; Ceular, Angel

    2017-02-01

    The aim of this study was to determine the effect of stocking density, light intensity and light color on broiler growth. The experiment consisted of four 35-day phases during each of which 320 chickens were surveyed. The research was performed at stocking densities of four and six birds/m(2) . Illuminances of 15 and 30 lx were obtained through commercial lamps with 4000 K and 6000 K color temperatures. Lighting was used 17 h a day, between 06.00 and 23.00 hours (17 L:7 D). The results showed a decrease in body, carcass, breast and thighs weight (P < 0.05) with the increase in stocking density. Body weight decreased by 10.5% and carcass weight decreased by 9.4% at six birds/m(2) stocking density. Contrastingly, no differences were found for the tested light colors. Increasing illuminance from 15 to 30 lx caused a 1.9% decrease in body weight. The analysis of the effect of perches revealed that using perches significantly increased body (2.5%) and breast weight (11.8%). The interactions between light intensity or color and stocking density and between light intensity and light color were analyzed. © 2016 Japanese Society of Animal Science.

  12. 36Cl in shallow, perched aquifers from central Indiana

    Science.gov (United States)

    Vogt, S.; Elmore, D.; Fritz, S. J.

    1994-06-01

    36Cl/Cl ratios and chloride concentrations were measured in several shallow, perched aquifers situated within glacial till in west-central Indiana (USA). Most of these aquifers show 36Cl/Cl ratios which have to be attributed to admixed 36Cl from nuclear weapons tests in the 1950s and 1960s. Two wells from Purdue's Horticultural Farm tap perched aquifers uninfluenced by anthropogenic sources of chloride, and their 36Cl/Cl ratios are comparable with ratios measured in modern, local precipitation. As such, the chloride contents of these wells (1 to 3 ppm) reflect evaporative concentration of the precipitation's chloride contents (averaging 0.17 ppm) in the vadose zone. Since one of these two wells (HA-2a) does not contain any detectable tritium, we conclude that recent pre-bomb 36Cl/Cl ratios and 36Cl deposition in precipitation are quite similar to those in modern precipitation. We attribute the slight 36Cl excess of about 20% in both of these wells largely to 36Cl deposition associated with dry fall-out. As much as 2 × 10 4 at. 36Cl/cm 2 might reach the surface via dry fall-out annually.

  13. Biology, History, Status and Conservation of Sacramento Perch, Archoplites interruptus

    Directory of Open Access Journals (Sweden)

    Patrick K Crain

    2011-04-01

    Full Text Available This paper is a review of the biology of Sacramento perch (Archoplites interruptus based mainly on recent studies of their distribution, ecology, physiology, and genetics. The Sacramento perch is the only member of the family Centrarchidae that is endemic to California. It is most closely related to the rock basses (Ambloplites spp. and is thought to have split from its eastern cousins during the Middle Miocene Period (15.5 to 5.2 million years ago, MYA. Their native range includes the Central Valley, Pajaro and Salinas rivers, tributaries to the San Francisco Estuary (e.g., Alameda Creek, and Clear Lake (Lake County. Today, they are most likely extirpated from all of their native range. They are known to persist in 28 waters outside their native range: 17 in California, nine in Nevada, and one each in Utah and Colorado. Disappearance from their native range coincided with massive changes to aquatic habitats in the Central Valley and with the introduction of alien species, including other centrarchids. Unfortunately, many populations established outside their native range have also disappeared and are continuing to do so.

  14. 76 FR 43934 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch for Catcher/Processors...

    Science.gov (United States)

    2011-07-22

    ... Economic Zone Off Alaska; Pacific Ocean Perch for Catcher/Processors Participating in the Rockfish Limited...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific ocean perch by catcher/processors... perch allocated to catcher/processors participating in the rockfish limited access fishery in the...

  15. 75 FR 42337 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch for Catcher/Processors...

    Science.gov (United States)

    2010-07-21

    ... Economic Zone Off Alaska; Pacific Ocean Perch for Catcher/Processors Participating in the Rockfish Limited...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific ocean perch by catcher/processors... perch allocated to catcher/processors participating in the rockfish limited access fishery in the...

  16. Beyond frontiers: Ancient Rome and the Eurasian trade networks

    Directory of Open Access Journals (Sweden)

    Marco Galli

    2017-01-01

    Full Text Available During the second half of the 19th century, the Roman Empire was already considered one of the key players inside the Eurasian networks. This research focuses on four relevant points. From a historiographical perspective, the reconstruction of the trading routes represented a central theme in the history of the relationship between the Roman Empire and the Far East. Imagining a plurality of itineraries and combinations of overland and sea routes, it is possible to reconstruct a complex reality in which the Eurasian networks during the Early Roman Empire developed. As far as economics is concerned, new documentation demonstrates the wide range and the extraordinary impact of the Eastern products on Roman markets. A final focus on the process of Chinese silk unravelling and reweaving provides an important clue on how complex and absolutely not mono-directional were the interactions and the exchanges in the Eurasian networks during the first centuries of the Roman Empire.

  17. Hatching success in brackish water of Perca fluviatilis eggs obtained from the western Baltic Sea

    DEFF Research Database (Denmark)

    Christensen, Emil Aputsiaq Flindt; Skovrind, Mikkel; Olsen, Morten Tange

    2016-01-01

    the population genetically among other European perch populations, individual egg samples were sequenced for a 390 base pair fragment of the mtDNA Dloop region. Hatching occurred at all four salinities, with no statistical differences among treatments. Successful hatching at 12 ‰ is well above salinities of 7...

  18. Letter Report: Stable Hydrogen and Oxygen Isotope Analysis of B-Complex Perched Water Samples

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Brady D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Moran, James J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Nims, Megan K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Saunders, Danielle L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2017-04-13

    Fine-grained sediments associated with the Cold Creek Unit at Hanford have caused the formation of a perched water aquifer in the deep vadose zone at the B Complex area, which includes waste sites in the 200-DV-1 Operable Unit and the single-shell tank farms in Waste Management Area B-BX-BY. High levels of contaminants, such as uranium, technetium-99, and nitrate, make this aquifer a continuing source of contamination for the groundwater located a few meters below the perched zone. Analysis of deuterium (2H) and 18-oxygen (18O) of nine perched water samples from three different wells was performed. Samples represent time points from hydraulic tests performed on the perched aquifer using the three wells. The isotope analyses showed that the perched water had δ2H and δ18O ratios consistent with the regional meteoric water line, indicating that local precipitation events at the Hanford site likely account for recharge of the perched water aquifer. Data from the isotope analysis can be used along with pumping and recovery data to help understand the perched water dynamics related to aquifer size and hydraulic control of the aquifer in the future.

  19. Food habits of stunted and non-stunted white perch (Morone americana)

    Science.gov (United States)

    Gosch, N.J.C.; Stittie, J.R.; Pope, K.L.

    2010-01-01

    We studied food habits of white perch (Morone americana) from two populations with different stable states (stunted [Branched Oak Lake, Nebraska] and nonstunted [Pawnee Lake, Nebraska]) to determine if change in food habits of white perch is likely to occur in situations where a stunted white perch population is altered to a nonstunted state and vice versa. Three approaches were used to quantitatively describe seasonal (spring = March-May, summer = June-August, autumn = September-November) diets of white perch - 1) frequency of occurrence, 2) percentage of composition by volume, and 3) mean stomach fullness. White perch diets were dominated by cladocerans and dipterans in both reservoirs during all seasons. Fish egg predation was similar between reservoirs, and white perch rarely consumed fishes in either the stunted or the non-stunted population. Shifting a white perch population between stunted and non-stunted states will likely cause little or no change in food habits; fish in both states will primarily consume invertebrates.

  20. Russia in the context of Eurasian integration: The social dimension

    Directory of Open Access Journals (Sweden)

    G I Osadchaya

    2015-12-01

    Full Text Available On the basis of empirical data (a number of representative nationwide opinion polls and expert estimates the article presented a detailed overview of the Russians’ and experts’ perception of the results and prospects of the Eurasian integration, and an analytical evaluation of their opinions, hopes and expectations taking into account the potential of the labor movement in the new integrated socio-economic and geopolitical space. The author explains the role and meaning of the social interaction of members of the Eurasian Economic Union (EEU in ensuring the effectiveness of integration, and proposes methodological foundations for the development of the social model of the Eurasian Union with an emphasis on its social dimension. The article reveals the essence of the today supranational model of social policy and its influence on social policies of the members of EEU. Thus, the author explains the primary need to harmonize social actions of the members of EEU in employment policies, and proposes a number of measures for social policy in Russia to ensure free movement of labor in the Eurasian economic space as a key host state and society.

  1. Ancient DNA reveals past existence of Eurasian lynx in Spain

    DEFF Research Database (Denmark)

    Rodríguez-Varela, R.; García, N.; Nores, C.

    2016-01-01

    The known distribution of the Iberian lynx Lynx pardinus within the Iberian Peninsula since the Middle Pleistocene and the lack of reliable records of Eurasian lynx Lynx lynx in this region have led to the assumption that the Iberian lynx was the sole inhabitant of Iberia. In this study, we ident...

  2. Deglaciation of the Eurasian ice sheet complex

    Science.gov (United States)

    Patton, Henry; Hubbard, Alun; Andreassen, Karin; Auriac, Amandine; Whitehouse, Pippa L.; Stroeven, Arjen P.; Shackleton, Calvin; Winsborrow, Monica; Heyman, Jakob; Hall, Adrian M.

    2017-08-01

    The Eurasian ice sheet complex (EISC) was the third largest ice mass during the Last Glacial Maximum with a span of over 4500 km and responsible for around 20 m of eustatic sea-level lowering. Whilst recent terrestrial and marine empirical insights have improved understanding of the chronology, pattern and rates of retreat of this vast ice sheet, a concerted attempt to model the deglaciation of the EISC honouring these new constraints is conspicuously lacking. Here, we apply a first-order, thermomechanical ice sheet model, validated against a diverse suite of empirical data, to investigate the retreat of the EISC after 23 ka BP, directly extending the work of Patton et al. (2016) who modelled the build-up to its maximum extent. Retreat of the ice sheet complex was highly asynchronous, reflecting contrasting regional sensitivities to climate forcing, oceanic influence, and internal dynamics. Most rapid retreat was experienced across the Barents Sea sector after 17.8 ka BP when this marine-based ice sheet disintegrated at a rate of ∼670 gigatonnes per year (Gt a-1) through enhanced calving and interior dynamic thinning, driven by oceanic/atmospheric warming and exacerbated by eustatic sea-level rise. From 14.9 to 12.9 ka BP the EISC lost on average 750 Gt a-1, peaking at rates >3000 Gt a-1, roughly equally partitioned between surface melt and dynamic losses, and potentially contributing up to 2.5 m to global sea-level rise during Meltwater Pulse 1A. Independent glacio-isostatic modelling constrained by an extensive inventory of relative sea-level change corroborates our ice sheet loading history of the Barents Sea sector. Subglacial conditions were predominately temperate during deglaciation, with over 6000 subglacial lakes predicted along with an extensive subglacial drainage network. Moreover, the maximum EISC and its isostatic footprint had a profound impact on the proglacial hydrological network, forming the Fleuve Manche mega-catchment which had an area of

  3. Eutrophication, Nile perch and food-web interactions in south-east Lake Victoria

    NARCIS (Netherlands)

    Cornelissen, I.J.M.

    2015-01-01

    The increasing eutrophication, the introduction of Nile perch (Lates niloticus) and the increasing fishing pressure has changed Lake Victoria tremendously the last century. Since the 1960s, eutrophication increased primary production, enabling an increase in fish production. However, eutrophication

  4. Characterization and Extraction of Uranium Contamination Perched within the Deep Vadose Zone at the Hanford Site, Washington State

    Science.gov (United States)

    Williams, B. A.; Rohay, V. J.; Benecke, M. W.; Chronister, G. B.; Doornbos, M. H.; Morse, J.

    2012-12-01

    A highly contaminated perched water zone has been discovered in the deep vadose zone above the unconfined aquifer during drilling of wells to characterize groundwater contamination within the 200 East Area of the U.S. Department of Energy's Hanford Site in southeast Washington. The perched water, which contains nitrate, uranium, and technetium-99 at concentrations that have exceeded 100,000 μg/L, 70,000 μg/L, and 45,000 pCi/L respectively, is providing contamination to the underlying unconfined aquifer. A perched zone extraction well has been installed and is successfully recovering the contaminated perched water as an early remedial measure to reduce impacts to the unconfined aquifer. The integration and interpretation of various borehole hydrogeologic, geochemical, and geophysical data sets obtained during drilling facilitated the delineation of the perching horizon and determination of the nature and extent of the perched contamination. Integration of the borehole geologic and geophysical logs defined the structural elevation and thickness of the perching low permeability silt interval. Borehole geophysical moisture logs, gamma logs, and sample data allowed detailed determination of the elevation and thickness of the oversaturated zone above the perching horizon, and the extent and magnitude of the radiological uranium contamination within the perching interval. Together, these data sets resolved the nature of the perching horizon and the location and extent of the contaminated perched water within the perching zone, allowing an estimation of remaining contaminant extent. The resulting conceptual model indicates that the contaminated perched water is contained within a localized sand lens deposited in a structural low on top of a semi-regional low-permeability silt layer. The top of the sand lens is approximately 72 m (235 ft) below ground surface; the maximum thickness of the sand lens is approximately 3 m (10 ft). The lateral and vertical extent of the

  5. Soft perches in an aviary system reduce incidence of keel bone damage in laying hens.

    Directory of Open Access Journals (Sweden)

    Ariane Stratmann

    Full Text Available Keel bone fractures and deviations are one of the major welfare and health issues in commercial laying hens. In non-cage housing systems like aviaries, falls and collisions with perches and other parts of the housing system are assumed to be one of the main causes for the high incidence of keel bone damage. The objectives of this study were to investigate the effectiveness of a soft perch material to reduce keel bone fractures and deviations in white (Dekalb White and brown laying hens (ISA Brown kept in an aviary system under commercial conditions. In half of 20 pens, all hard, metal perches were covered with a soft polyurethane material. Palpation of 20 hens per pen was conducted at 18, 21, 23, 30, 38, 44 and 64 weeks of age. Production data including egg laying rate, floor eggs, mortality and feed consumption were collected over the whole laying period. Feather condition and body mass was assessed twice per laying period. The results revealed that pens with soft perches had a reduced number of keel bone fractures and deviations. Also, an interaction between hybrid and age indicated that the ISA hybrid had more fractured keel bones and fewer non-damaged keel bones compared with the DW hybrid at 18 weeks of age, a response that was reversed at the end of the experiment. This is the first study providing evidence for the effectiveness of a soft perch material within a commercial setting. Due to its compressible material soft perches are likely to absorb kinetic energy occurring during collisions and increase the spread of pressure on the keel bone during perching, providing a mechanism to reduce keel bone fractures and deviations, respectively. In combination with genetic selection for more resilient bones and new housing design, perch material is a promising tool to reduce keel bone damage in commercial systems.

  6. Investigation of groundwater recirculation for the removal of RDX from the Pantex Plant perched aquifer

    Energy Technology Data Exchange (ETDEWEB)

    Woods, A.L. [ed.; Barnes, D.L. [Amarillo National Resource Center for Plutonium, TX (United States); Boles, K.M.; Charbeneau, R.J. [Univ. of Texas, Austin, TX (United States); Black, S.; Rainwater, K. [Texas Tech Univ., Lubbock, TX (United States). Water Resources Center

    1998-07-01

    The Pantex Plant near Amarillo, Texas, is a US Department of Energy (DOE) facility that has been in operation since 1942. Past and present operations at Pantex include the creation of chemical high explosives components for nuclear weapons and assembly and disassembly of nuclear weapons. The Pantex Plant is underlain by the Ogallala aquifer, which in this area, consists of the main water-bearing unit and a perched water zone. These are separated by a fine-grained zone of low permeability. Multiple contaminant plumes containing high explosive (HE) compounds have been detected in the perched aquifer beneath the plant. The occurrence of these contaminants is the result of past waste disposal practices at the facility. RDX is an HE compound, which has been detected in the groundwater of the perched aquifer at significant concentrations. A pilot-scale, dual-phase extraction treatment system has been installed at one location at the plant, east of Zone 12, to test the effectiveness of such a system on the removal of these contaminants from the subsurface. A tracer test using a conservative tracer, bromide (Br), was conducted at the treatment site in 1996. In addition to the bromide, RDX and water elevations in the aquifer were monitored. Using data from the tracer test and other relevant data from the investigations at Pantex, flow and contaminant transport in the perched aquifer were simulated with groundwater models. The flow was modeled using MODFLOW and the transport of contaminants in the aqueous phase was modeled using MT3D. Modeling the perched aquifer had been conducted to characterize the flow in the perched aquifer; estimate RDX retardation in the perched aquifer; and evaluate the use of groundwater re-circulation to enhance the extraction of RDX from the perched aquifer.

  7. Nitrate-nitrogen concentrations in the perched ground water under seepage-irrigated potato cropping systems.

    Science.gov (United States)

    Munoz-Arboleda, F; Mylavarapu, R; Hutchinson, C; Portier, K

    2008-01-01

    Excessive nitrogen rates for potato production in northeast Florida have been declared as a potential source of nitrate pollution in the St. Johns River watershed. This 3-yr study examined the effect of N rates (0, 168, and 280 kg ha(-1)) split between planting and 40 d after planting on the NO(3)-N concentration in the perched ground water under potato (Solanum tuberosum cv. Atlantic) in rotation with sorghum sudan grass hybrid (Sorghum vulgare x Sorghum vulgare var. sudanese, cv. SX17), cowpea (Vigna unguiculata cv. Iron Clay), and greenbean (Phaseolus vulgare cv. Espada). Soil solution from the root zone and water from the perched ground water under potato were sampled periodically using lysimeters and wells, respectively. Fertilization at planting increased the NO(3)-N concentration in the perched ground water, but no effect of the legumes in rotation with potatoes on nitrate leaching was detected. Fertilization of green bean increased NO(3)-N concentration in the perched ground water under potato planted in the following season. The NO(3)-N concentration in the soil solution within the potato root zone followed a similar pattern to that of the perched ground water but with higher initial values. The NO(3)-N concentration in the perched ground water was proportional to the rainfall magnitude after potato planting. A significant increase in NO(3)-N concentration in the perched ground water under cowpea planted in summer after potato was detected for the side-dressing of 168 kg ha(-1) N applied to potato 40 d after planting but not at the 56 kg ha(-1) N side-dress. Elevation in NO(3)-N concentration in the perched ground water under sorghum was not significant, supporting its use as an effective N catch crop.

  8. Impact of impingement on the Hudson River white perch population. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Barnthouse, L.W.; Van Winkle, W.; Kirk, B.L.; Vaughan, D.S.

    1982-02-01

    This report summarizes a series of analyses of the magnitude and biological significance of the impingement of white perch at the Indian Point Nuclear Generating Station and other Hudson River power plants. Included in these analyses were evaluations of: (1) two independent lines of evidence relating to the magnitude of impingement impacts on the Hudson River white perch population; (2) the additional impact caused by entrainment of white perch; (3) data relating to density-dependent growth among young-of-the-year white perch; (4) the feasibility of performing population-level analyses of impingement impacts on the white perch populations of Chesapeake Bay and the Delaware River; and (5) the feasibility of using simple food chain and food web models to evaluate community-level effects of impingement and entrainment. Estimated reductions in the abundances of the 1974 and 1975 white perch year classes, caused by impingement and entrainment, were high enough that the possibility of adverse long-term effects cannot be excluded.

  9. Bio-Inspired Trajectory Generation for UAV Perching Movement Based on Tau Theory

    Directory of Open Access Journals (Sweden)

    Zhen Zhang

    2014-09-01

    Full Text Available This paper offers a bio-inspired trajectory generation method for UAV/MAV perching (i.e., the final approach to, and landing on, a target. The method is based on tau theory, which was established based on the study of the natural motion patterns of animals (including humans when they approach a fixed or moving object for perching or capturing prey. In our research, tau theory is applied to the trajectory generation problem of an air vehicle for perching on a target object. Three bio-inspired strategies, namely the tau in the action gap strategy, the tau coupling strategy and the intrinsic tau gravity strategy are studied for perching tasks. A key parameter of the method inspired by biological systems is discussed. Two perching scenarios, one from a flight state (with non-zero initial velocity and one from a hovering state (with zero initial velocity, are studied. Numerical simulations with a rotary vehicle are presented as examples to demonstrate the performance of the proposed approach. The simulation results show that the resulting flight trajectories meet all the desired requirements for the vehicle in perching on an object.

  10. Haematological studies of climbing perch (Anabas testudineus Bloch

    Directory of Open Access Journals (Sweden)

    Sukasem, N.

    2005-02-01

    Full Text Available Some blood parameters of the climbing perch (Anabas testudineus Bloch i.e. red (RBC and white (WBC blood cell count, percent haematocrit (HTC, hemoglobin, plasma protein as well as hepatosomatic index (HSI were studied. There were no statistically significant difference (p>0.05 in average body weight and length of fish from the earthen pond and net cage culture, which were 16.85±1.46 g and 16.24±2.42 g, respectively, for the weight and 10.02±0.25 and 9.74±0.37 cm, respectively, for the length. Haematologicalstudies revealed that RBC, WBC including percent HTC levels of the fish from earthen pond and net cage were not significantly different (> 0.05. Whereas hemoglobin and serum protein concentration of the fish sampling from net cage were higher than those sampled from the earthen pond (p<0.05, with value of 12.21± 0.91 g/dl and 11.12±0.85 g/dl for hemoglobin and 4.61±0.50 mg/dl and 3.87±0.62 mg/dl for serum protein, respectively. HSI of the fish cultured in the earthen pond was significantly (p<0.05 higher than that of fish reared in net cage, with value of 1.93±0.12% and 1.66±0.12%, respectively.

  11. Ancient Ethiopian genome reveals extensive Eurasian admixture in Eastern Africa

    KAUST Repository

    Gallego Llorente, M.

    2015-10-09

    Characterizing genetic diversity in Africa is a crucial step for most analyses reconstructing the evolutionary history of anatomically modern humans. However, historic migrations from Eurasia into Africa have affected many contemporary populations, confounding inferences. Here, we present a 12.5×coverage ancient genome of an Ethiopian male ("Mota") who lived approximately 4500 years ago. We use this genome to demonstrate that the Eurasian backflow into Africa came from a population closely related to Early Neolithic farmers, who had colonized Europe 4000 years earlier. The extent of this backflow was much greater than previously reported, reaching all the way to Central, West, and Southern Africa, affecting even populations such as Yoruba and Mbuti, previously thought to be relatively unadmixed, who harbor 6 to 7% Eurasian ancestry.

  12. Trichomonosis in Eurasian sparrowhawks in the Czech Republic.

    Science.gov (United States)

    Kunca, Tomas; Smejkalova, Pavla; Cepicka, Ivan

    2015-07-07

    Pigeon, doves and songbirds are hosts of the parasite Trichomonas gallinae (Rivolta, 1878), which causes avian trichomonosis. Raptors are infected when they digest infected prey. A high percentage of the diet of Eurasian sparrowhawk Accipiter nisus (Linnaeus) is comprised of birds. During the breeding season 2012 and 2013, we clinically tested 298 nestling Eurasian sparrowhawks from urban and rural areas of the Czech Republic for the presence of trichomonads. Sparrowhawk nestlings in the urban area were more infected (32.9%) than in the rural area (12.2%) in 2012 (χ(2) = 6.184, P = 0.045). The number of infected nestlings dropped in the urban area (5.4%) and remained similar in the rural area (16.6%) in 2013. Sequences of ITS region and SSU rDNA confirmed that the isolates from infected sparrowhawk nestlings belonged to Trichomonas gallinae.

  13. Assessing controls on perched saturated zones beneath the Idaho Nuclear Technology and Engineering Center, Idaho

    Science.gov (United States)

    Mirus, Benjamin B.; Perkins, Kim S.; Nimmo, John R.

    2011-01-01

    Waste byproducts associated with operations at the Idaho Nuclear Technology and Engineering Center (INTEC) have the potential to contaminate the eastern Snake River Plain (ESRP) aquifer. Recharge to the ESRP aquifer is controlled largely by the alternating stratigraphy of fractured volcanic rocks and sedimentary interbeds within the overlying vadose zone and by the availability of water at the surface. Beneath the INTEC facilities, localized zones of saturation perched on the sedimentary interbeds are of particular concern because they may facilitate accelerated transport of contaminants. The sources and timing of natural and anthropogenic recharge to the perched zones are poorly understood. Simple approaches for quantitative characterization of this complex, variably saturated flow system are needed to assess potential scenarios for contaminant transport under alternative remediation strategies. During 2009-2011, the U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Energy, employed data analysis and numerical simulations with a recently developed model of preferential flow to evaluate the sources and quantity of recharge to the perched zones. Piezometer, tensiometer, temperature, precipitation, and stream-discharge data were analyzed, with particular focus on the possibility of contributions to the perched zones from snowmelt and flow in the neighboring Big Lost River (BLR). Analysis of the timing and magnitude of subsurface dynamics indicate that streamflow provides local recharge to the shallow, intermediate, and deep perched saturated zones within 150 m of the BLR; at greater distances from the BLR the influence of streamflow on recharge is unclear. Perched water-level dynamics in most wells analyzed are consistent with findings from previous geochemical analyses, which suggest that a combination of annual snowmelt and anthropogenic sources (for example, leaky pipes and drainage ditches) contribute to recharge of shallow and

  14. INTERESTS OF THE MEMBER STATES IN THE EURASIAN ECONOMIC UNION

    OpenAIRE

    Tomasz Michałowski

    2016-01-01

    The article presents the interests of the member countries in the Eurasian Economic Union (EEU), which is formed by Russia, Belarus, Kazakhstan, Armenia and Kyrgyzstan. The author argues that Russia has been involved in the project primarily for geopolitical reasons. Belarus, Kazakhstan, Armenia and Kyrgyzstan have perceived the integration within EEU primarily through the possible economic benefits. While analyzing the interests of the members in the EEU, the author also refers to the develo...

  15. EURASIAN LANGUAGES: THE BASIS OF ALLOCATION, LOGICS, SEMANTICS

    Directory of Open Access Journals (Sweden)

    KHALINA NATALIYA VASILIEVNA

    2015-01-01

    Full Text Available In the article the authors show the logical basis for the idea of J. Greenberg about Eurasian languages. A dominant position of this idea is the assertion that all the languages of Central and South America are included in the Amerind gens. The logic of fuzzy sets or fuzzy logic is examined as a logical foundation of J. Greenberg's concept. A linguistic variable "truth" takes a special place in this logic.

  16. Russian neo-revisionist strategy and the Eurasian Project

    Directory of Open Access Journals (Sweden)

    Ruslan Dzarasov

    2017-03-01

    Full Text Available The article is focused on the real meaning of the Eurasian Integration Project for East–West relations. The author departs from Sakwa’s treatment of Russian strategy as neo-revisionist. It does not aspire to change the current world order while trying to make the West observe its national interests within the existing framework. This perspective is treated in the article from the standpoint of world-systems analysis. The Eurasian Project is understood as a reaction of the Russian state to the failure of the neoliberal attempt to integrate into the world economy and the international security system. The two great trade mega-unions—the Trans-Pacific Partnership (TPP and the Trans-Atlantic Partnership—are seen as geoeconomic bolt clamps, which put Russia under enormous pressure. The Russian strategy in the Ukrainian and Syrian crises is designed to find the way out of strategic isolation. The Eurasian Union is expected by the Russian ruling elite to be an important tool to forestall the isolation of the country and secure her economic, military and international security.

  17. Woody structure facilitates invasion of woody plants by providing perches for birds.

    Science.gov (United States)

    Prather, Chelse M; Huynh, Andrew; Pennings, Steven C

    2017-10-01

    Woody encroachment threatens prairie ecosystems globally, and thus understanding the mechanisms that facilitate woody encroachment is of critical importance. Coastal tallgrass prairies along the Gulf Coast of the US are currently threatened by the spread of several species of woody plants. We studied a coastal tallgrass prairie in Texas, USA, to determine if existing woody structure increased the supply of seeds from woody plants via dispersal by birds. Specifically, we determined if (i) more seedlings of an invasive tree ( Tridacia sebifera ) are present surrounding a native woody plant ( Myrica cerifera ); (ii) wooden perches increase the quantity of seeds dispersed to a grassland; and (iii) perches alter the composition of the seed rain seasonally in prairie habitats with differing amounts of native and invasive woody vegetation, both underneath and away from artificial wooden perches. More T. sebifera seedlings were found within M. cerifera patches than in graminoid-dominated areas. Although perches did not affect the total number of seeds, perches changed the composition of seed rain to be less dominated by grasses and forbs. Specifically, 20-30 times as many seeds of two invasive species of woody plants were found underneath perches independent of background vegetation, especially during months when seed rain was highest. These results suggest that existing woody structure in a grassland can promote further woody encroachment by enhancing seed dispersal by birds. This finding argues for management to reduce woody plant abundance before exotic plants set seeds and argues against the use of artificial perches as a restoration technique in grasslands threatened by woody species.

  18. Robust jumping performance and elastic energy recovery from compliant perches in tree frogs.

    Science.gov (United States)

    Astley, Henry C; Haruta, Alison; Roberts, Thomas J

    2015-11-01

    Arboreal animals often move on compliant branches, which may deform substantially under loads, absorbing energy. Energy stored in a compliant substrate may be returned to the animal or it may be lost. In all cases studied so far, animals jumping from a static start lose all of the energy imparted to compliant substrates and performance is reduced. Cuban tree frogs (Osteopilus septentrionalis) are particularly capable arboreal jumpers, and we hypothesized that these animals would be able to recover energy from perches of varying compliance. In spite of large deflections of the perches and consequent substantial energy absorption, frogs were able to regain some of the energy lost to the perch during the recoil. Takeoff velocity was robust to changes in compliance, but was lower than when jumping from flat surfaces. This highlights the ability of animals to minimize energy loss and maintain dependable performance on challenging substrates via behavioral changes. © 2015. Published by The Company of Biologists Ltd.

  19. ASEAN-LED MULTILATERAL SECURITY DIALOGUE: EURASIAN PRIORITIES

    Directory of Open Access Journals (Sweden)

    Е А Канаев

    2017-12-01

    Full Text Available The article focuses upon new aspects in ASEAN priorities relevant to the rise of efficiency of ASEAN-led multilateral dialogues platforms - ASEAN Regional Forum (ARF, ASEAN Defense Ministers Meeting Plus Eight (ADMM+8 and East Asia Summit (EAS. Having outlined the conceptual contradiction between the rise of the global component in Asia-Pacific security challenges, the authors trace the intellectual and practical dimensions of ASEAN response. On reviewing the key directions of intra-ASEAN expert discussions, the authors reveal their qualitatively new component - to link the modi-fication of ASEAN modality of cooperation and its expansion to the Eurasian area. The trace of factors responsible for the possibility and necessity to adopt ARF, ADMM+8 and EAS to the impeding format ASEAN-SCO-EAEU and practically-oriented proposals about the promising directions of cooperation within this format are the key academic value-added of the study. The actuality and academic significance of the study stem from the necessity to analyze issues important for ASEAN and its Eurasian partners. Among these issues, the key are: which directions of cooperation can be of help for ASEAN in order to strengthen its positions as the driving force of Asia-Pacific multilateral dialogue frameworks? By what means can ASEAN and ASEAN-led formats be integ-rated in the establishment of Greater Eurasia with the maximum outcomes for both ASEAN and its Eurasian partners? How can ASEAN experience be used for the establishment of an efficient trans-continental rather than regional multilateral security dialogue? Findings on these issues make the article academi-cally unique.

  20. INTERESTS OF THE MEMBER STATES IN THE EURASIAN ECONOMIC UNION

    Directory of Open Access Journals (Sweden)

    Tomasz Michałowski

    2016-12-01

    Full Text Available The article presents the interests of the member countries in the Eurasian Economic Union (EEU, which is formed by Russia, Belarus, Kazakhstan, Armenia and Kyrgyzstan. The author argues that Russia has been involved in the project primarily for geopolitical reasons. Belarus, Kazakhstan, Armenia and Kyrgyzstan have perceived the integration within EEU primarily through the possible economic benefits. While analyzing the interests of the members in the EEU, the author also refers to the development of the economic situation in each country in recent years. The starting point for discussion is the analysis of benefits of economic integration in the light of theory.

  1. Helminth fauna of Eurasian lynx (Lynx lynx) in Estonia.

    Science.gov (United States)

    Valdmann, H; Moks, E; Talvik, H

    2004-04-01

    Thirty-seven carcasses of Eurasian lynx (Lynx lynx) collected and examined in Estonia during 1999-2001 had helminths. Parasites identified and their prevalence included Diphyllobothrium latum (5%), Taenia pisiformis (100%), Taenia laticollis (41%), Taenia hydatigena (3%), Taenia taeniaeformis (3%), Toxocara cati (68%), and Trichinella spp. (22%). The only significant relationships (P lynx, and older males had a greater number of species of helminth than did younger lynx. Sixty-one fecal samples collected during snow tracking of nine lynx were examined; eggs of T. cati were identified in 38 samples, and Capillaria spp were found in eight samples. This is the first systematic investigation of parasites of lynx in Estonia.

  2. Echolocation intensity and directionality of perching and flying fringe-lipped bats, Trachops cirrhosus (Phyllostomidae)

    DEFF Research Database (Denmark)

    Surlykke, Annemarie; Jakobsen, Lasse; Kalko, Elisabeth K V

    2013-01-01

    The Neotropical frog-eating bat, Trachops cirrhosus, primarily hunts stationary prey, either by gleaning on the wing, or in a sit-and-wait mode hanging from a perch. It listens passively for prey-generated sounds, but uses echolocation in all stages of the hunt. Like other bats in the family...... with closed and open mouth. We hypothesize that its flexibility extends to echolocation call design. We investigated the effect of hunting mode, perching or flying, as well as the effect of mouth opening, on the acoustic parameters and directionality of the echolocation call. We used a multi-microphone array...

  3. Susceptibility of pike-perch Sander lucioperca to a panel of ranavirus isolates

    DEFF Research Database (Denmark)

    Jensen, Britt Bang; Holopainen, Riikka; Tapiovaara, Hannele

    2011-01-01

    The host range of ranaviruses was investigated by challenging pike-perch (Sander lucioperca) with the following ranavirus isolates: epizootic haematopoietic necrosis virus (EHNV), European sheatfish virus (ESV), European catfish virus (ECV), pike-perch iridovirus (PPIV), short-finned eel virus...... challenge with EHNV, ESV, ECV and PPIV at 16°C. Statistically significant mortality was observed in EHNV-challenged fish at both temperatures in the five week old fish. No mortalities were seen in older fish challenged with EHNV and PPIV. High mortalities were registered in i.p.-challenged fish...

  4. Eurasian polities as hybrid regimes: The case of Putin's Russia

    Directory of Open Access Journals (Sweden)

    Henry E. Hale

    2010-01-01

    Full Text Available Most Eurasian countries' political systems are not accurately described as some version of either democracy or authoritarianism. Nor does it advance social science to study each of these countries' political systems as being completely unique, sharing no significant commonalities with those of other countries. Instead, it is more fruitful to understand many Eurasian countries as a type of hybrid regime, a system that combines important elements of both democracy and autocracy in some way. One of the most important features of Eurasia's hybrid regimes, one that is shared by many hybrid regimes worldwide, is that they combine contested elections with pervasive political clientelism. Political developments in these countries can thus be usefully understood as machine politics, and the development of political systems can be understood as processes of rearranging the components of the machines in different ways. The usefulness of this approach is demonstrated through an in-depth study of the Russian Federation. It is argued that Russian political development under Putin is best understood not as “authoritarianization” but as a process in which Russia transitioned from a system of “competing pyramids” of machine power to a “single-pyramid” system, a system dominated by one large political machine. It turns out that in single-pyramid systems that preserve contested elections, as does Russia, public opinion matters more than in typical authoritarian regimes.

  5. Interregional Cooperation in the Emerging Eurasian Economic Space

    Directory of Open Access Journals (Sweden)

    Konstantin Anatol’evich Gulin

    2015-11-01

    Full Text Available In 2015 the Treaty on the Eurasian Economic Union entered into force and presented a new stage of reintegration of the countries on the territory of the former USSR. The success of this project will depend not only on collaboration at the national level, but also on the degree of the EEU countries’ involvement in the integration process. The academic debate on this issue is a relevant and practically important task. The article highlights the results of the international online-conference “Interregional cooperation in the emerging Eurasian Economic Space”, conducted by the Institute of Socio-Economic Development of Territories of RAS June, 16–20 2015. It considers the issues associated with interregional trade and economic cooperation, interaction in the sphere of science and innovation and various aspects of humanitarian cooperation. It raises important problems of cross-border cooperation of the EEU states. The article makes a conclusion about the need to develop the integration process both in scope (through expanded directions of cooperation, which should not be limited only to contacts at the highest political level or trade partnership and depth (through involvement of regions, enterprises, different social groups, individual citizens

  6. Nile perch fish processing waste along Lake Victoria in East Africa ...

    African Journals Online (AJOL)

    Worldwide, fish industry wastes are an important contaminant having an impact on the environment. The recovery of value added products from these residues constitutes an important waste reduction strategy for the industry. In East Africa, Nile perch fish processing into chilled fish fillet for export along Lake Victoria ...

  7. Fatty acid composition of muscle and heart tissue of Nile perch ...

    African Journals Online (AJOL)

    The fatty acid composition in the heart tissue and muscle tissue of the Nile perch, Lates niloticus, and Nile tilapia, Oreochromis niloticus populations from Lakes Kioga and Victoria was determined by methanolysis and gas chromatography of the resulting fatty acid methyl esters. The analytical data were treated by ...

  8. The diets of Nile perch ( Lates niloticus ) in Oyan Dam | Adeosun ...

    African Journals Online (AJOL)

    Samples of Nile perch (Lates niloticus L.) were collected for stomach analysis from artisanal fishermen using fishing gear such as, cast nets, gill nets, set nets, in Oyan dam, Abeokuta, Ogun state, Nigeria. Frequency of Occurrence and Numerical methods was used to analyse the stomach contents of 60 specimens of Lates ...

  9. Whole body and egg amino acid composition of Nile perch, Lates ...

    African Journals Online (AJOL)

    Windows User

    weight gain (Martinez-Palacios et al., 2007; Zuanon et al.,. 2009). Amino acid assays have been widely done to ...... Beuving JJ. (2010). Playing pool along the shore of Lake Victoria: Fishermen, careers, and capital accumulation in the Ugandan Nile perch business. Africa 80(2):224-248. Bordieri L, di Patti MC, Miele R, ...

  10. Perched-Water Evaluation for the Deep Vadose Zone Beneath the B, BX, and BY Tank Farms Area of the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Truex, Michael J.; Oostrom, Martinus; Carroll, KC; Chronister, Glen B.

    2013-06-28

    Perched-water conditions have been observed in the vadose zone above a fine-grained zone that is located a few meters above the water table within the B, BX, and BY Tank Farms area. The perched water contains elevated concentrations of uranium and technetium-99. This perched-water zone is important to consider in evaluating the future flux of contaminated water into the groundwater. The study described in this report was conducted to examine the perched-water conditions and quantitatively evaluate 1) factors that control perching behavior, 2) contaminant flux toward groundwater, and 3) associated groundwater impact.

  11. Robust post-stall perching with a simple fixed-wing glider using LQR-Trees.

    Science.gov (United States)

    Moore, Joseph; Cory, Rick; Tedrake, Russ

    2014-06-01

    Birds routinely execute post-stall maneuvers with a speed and precision far beyond the capabilities of our best aircraft control systems. One remarkable example is a bird exploiting post-stall pressure drag in order to rapidly decelerate to land on a perch. Stall is typically associated with a loss of control authority, and it is tempting to attribute this agility of birds to the intricate morphology of the wings and tail, to their precision sensing apparatus, or their ability to perform thrust vectoring. Here we ask whether an extremely simple fixed-wing glider (no propeller) with only a single actuator in the tail is capable of landing precisely on a perch from a large range of initial conditions. To answer this question, we focus on the design of the flight control system; building upon previous work which used linear feedback control design based on quadratic regulators (LQR), we develop nonlinear feedback control based on nonlinear model-predictive control and 'LQR-Trees'. Through simulation using a flat-plate model of the glider, we find that both nonlinear methods are capable of achieving an accurate bird-like perching maneuver from a large range of initial conditions; the 'LQR-Trees' algorithm is particularly useful due to its low computational burden at runtime and its inherent performance guarantees. With this in mind, we then implement the 'LQR-Trees' algorithm on real hardware and demonstrate a 95 percent perching success rate over 147 flights for a wide range of initial speeds. These results suggest that, at least in the absence of significant disturbances like wind gusts, complex wing morphology and sensing are not strictly required to achieve accurate and robust perching even in the post-stall flow regime.

  12. Remedies for a high incidence of broken eggs in furnished cages: effectiveness of increasing nest attractiveness and lowering perch height.

    Science.gov (United States)

    Tuyttens, F A M; Struelens, E; Ampe, B

    2013-01-01

    Two remedial treatments to reduce the high incidence of broken eggs in the furnished cages of our experimental layer farm were investigated: lining the nest floor with artificial turf (to increase nest acceptance) and lowering perch height (to reduce the chance of egg breakage of outside-nest eggs). A 2 × 2 factorial design was used with low (7 cm) or high (24 cm) perches, and with nest floors lined with artificial turf or plastic mesh. Eight cages, each housing 8 hens initially (aged 40 to 56 wk), were used per treatment. Egg location and percentage of broken eggs were recorded. Hen position (cage floor, nest, or perch) was recorded by direct scan-sampling observations. In addition, 8 cages (4 high + 4 low) each containing 8 hens (aged 54 to 56 wk) were videorecorded to determine perch use and behavior during the light period. Data were mainly analyzed using logistic regression and mixed models with cage as the experimental unit. Nest floor material did not influence the percentage of eggs broken or laid outside the nest. The proportion of outside-nest eggs (2.6 vs. 10.6%, P = 0.004), and consequently also of total eggs (2 vs. 4.6%, P = 0.016) broken, was lower for low than high cages. Perch use increased during the observation period, more so for the high cages during the light period and the low cages during the dark period. Perch bout duration (P nest floor lining with artificial turf was not an effective remedy for the already-high rate of broken eggs, but the prevalence of broken outside-nest eggs was lower in cages with low versus high perches. However, perching behavior during the light period was more disturbed in cages with low perches.

  13. An Enormous Interstitial Mestizo? The (Impossibility of Eurasian Identity in Dutch Postcolonial Novels

    Directory of Open Access Journals (Sweden)

    Boudewijn Petra R.

    2016-06-01

    Full Text Available This article examines the (impossibility of Eurasian identity in Dutch postcolonial novels by second-generation authors such as Marion Bloem and Adriaan van Dis. As a result of Indonesia’s decolonisation 300.000 Dutch nationals came from the former Dutch East Indies to the Netherlands. Among them was a large group of Eurasians, people of mixed Dutch and Indonesian descent. Many of whom had never set foot on the so-called motherland. Although Eurasians had belonged to the European community in the tropics, they were perceived as immigrants by the Dutch government and were subjected to an aggressive, far-reaching assimilation policy - fearing they would otherwise become a major social problem. Their offspring, the so-called second generation, is often assumed to struggle with their identity while growing up in a postcolonial society that did not tolerate cultural differences at the time. What constitutes a Eurasian identity, and can such identities exist after the enforced assimilation of Eurasians in the Netherlands? How do second-generation authors look upon their Eurasian background and how do they portray these assumed identity struggles in postcolonial literature? The texts in question are discussed in relation to theories of hybridity. It is argued that the widespread notion that Eurasians either fall between two stools or grow into examples of hybrid identity are not foregone conclusions.

  14. Dynamics and stress field of the Eurasian plate

    Science.gov (United States)

    Warners-Ruckstuhl, Karin; Govers, Rob; Wortel, Rinus

    2013-04-01

    We address the connection between forces on the Eurasian plate, the plate's motion and the intraplate stress field. Resistive forces along convergent plate boundaries have a major impact on surface deformation, most visibly at collisional plate boundaries. Although quantification of these forces is key to understanding the evolution and present state of mountain belts, they remain highly uncertain due to the complexity of plate boundary structures and rheologies. In this study we analyse the forces along the southern boundary of the Eurasian plate, presently the most prominent suture zone on Earth, resulting from the closure of the Neo-Tethys ocean. We address the dynamics of the Eurasian plate as a whole. This enables us to base our analysis on mechanical equilibrium of a tectonic plate and to evaluate the force distribution along the Tethyan boundary as part of an internally consistent set of forces driving and deforming Eurasia. We evaluate force distributions obeying this mechanical law on the basis of their ability to reproduce observed stress orientations. We incorporate tractions from convective mantle flow modelling in a lithospheric model in which edge and lithospheric body forces are modelled explicitly and compute resulting stresses in a homogeneous elastic thin shell. Our investigation is structured according to two research objectives, pursued in a corresponding step-wise approach: (1) a detailed understanding of the sensitivity of Eurasia's stress field to the distribution of all acting forces; and (2) a quantification of collision-related forces along the southern boundary of Eurasia, including their relation to observed plate boundary structure, in particular plateau height. Intraplate stress observations as compiled in the World Stress Map project are used to constrain the distribution of forces acting on Eurasia. Eurasia's stress field turns out to be sensitive to the distribution of collision forces on the plate's southern margin and, to a lesser

  15. Otodectic otoacariasis in free-ranging Eurasian lynx in Sweden.

    Science.gov (United States)

    Degiorgis, M P; Segerstad, C H; Christensson, B; Mörner, T

    2001-07-01

    An infestation with Otodectes cynotis, the ear mite of cats and dogs, was observed in three free-ranging Eurasian lynx (Lynx lynx) killed in Sweden. The ear canals were obstructed by waxy secretions and exfoliated epithelium. Histologically, there were hyperkeratosis and acanthosis, and the epithelial surface was overlained by hyperkeratotic and parakeratotic crusts with mites, mite detritus and cerumen. In the subcutis there was a slight to moderate infiltration of lymphocytes and macrophages. The ceruminous glands were bypertrophic and hyperplastic, and there was also an hyperplasia of the sebaceous glands. The lesions seemed to correlate with the degree of infestation. To our knowledge, this is the first report of otoacariasis in free-ranging lynx.

  16. The reasons of creation of the Eurasian Economic Union: economics or politics?

    Directory of Open Access Journals (Sweden)

    Mukhametov Ruslan Salikhovich

    2015-12-01

    Full Text Available The article considers creation of the Eurasian economic Union. It is shown that Russia is the main provider of integration in the post-Soviet space. The author identifies several reasons for the establishment of the Eurasian economic Union. Much attention is paid to geo-economic reasons. It is clear that the Eurasian economic Union is a geopolitical project for Moscow. The author believes that domestic political considerations also support the motive of integration processes in the post-Soviet space.

  17. Surface-Atmosphere Moisture Coupling in Eurasian Frozen Ground Regions

    Science.gov (United States)

    Frauenfeld, O. W.; Ford, T.

    2014-12-01

    Permafrost represents an impermeable barrier to moisture, resulting in a saturated or near-saturated surface layer during the warm season in many continuous and discontinuous permafrost zones. These surface conditions could lead to enhanced convection and precipitation during the warm season, and significant local recycling of moisture. In areas underlain by sporadic or isolated permafrost, or in seasonally frozen areas, the moisture can drain away more readily, resulting in much drier soil conditions. As climate change causes frozen ground degradation, this will thus also alter the patterns of atmospheric convection, moisture recycling, and the hydrologic cycle in high-latitude land areas. In this study, we analyze evaporative fraction (EF) as a proxy for evapotranspiration, and precipitation from the Modern-Era Retrospective analysis for Research and Applications (MERRA-land) reanalysis dataset. We focus on 1979-2012 and document patterns and changes in EF over the Eurasian high latitudes. We find strong, positive April EF trends over the study period, particularly in the Lena River Basin, 80% of which is underlain by continuous permafrost. In fact, these significant positive trends in spring EF are strongest over continuous permafrost across the Eurasian high latitudes, but negative for sporadic and isolated permafrost. In addition, we find a strong, statistically significant relationship between EF anomalies and the probability of subsequent precipitation over the Lena Basin during April. This association therefore suggests a potential land-atmosphere coupling between frozen ground and precipitation. As the permafrost and seasonally frozen ground distribution changes in the future, this will likely have repercussions for the Arctic hydrologic cycle.

  18. Fins coloration of perch in relation to external activity concentration of radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Yegoreichenkov, E.; Pryakhin, E. [Urals Research Center for Radiation Medicine (Russian Federation); Rudolfsen, G. [Norwegian Radiation Protection Authority and University of Tromsoe (Norway)

    2014-07-01

    The Techa River is significantly polluted by radionuclides. This time the content of {sup 90}Sr varies from 5 Bq/l in water of lower Techa to 40 Bq/l in higher Techa, and the concentration of {sup 137}Cs fluctuates from background content to 0,5 Bq/l, and tritium from 100 Bq/l to 450 Bq/l. Miass River are not polluted in the same extent. The perch in these rivers are suitable for examine the potential effect of environmental perturbation on carotenoid based coloration. As vertebrates could not produce carotenoids themselves, and would use more carotenoids due to oxidative stress when exposed radiation, we hypothesized that fish caught in upper part of Techa River will be more pale than fish from lower part and the control river Miass. We used a cost effective method to estimate coloration by photographing the fins in standardized setting. The measuring of fish fins as performed under standardized condition by Adobe Photoshop software in color spaces CIE 1976 L*a*b* and sRGB IEC61966-2.1 was used. In sRGB color space the values of Red, Green, Blue channels were measured and an average wave length was calculated as a function of three elementary light streams of different intensity, appeared as reflection from a fin. In L*a*b color space the values of *a and *b channels shows the position of a color in a color space. To evaluate the red color of a perch fin the most usable channel is the *a channel which shows the position of the color on the red-green axis. Due to low sample size we pooled males and females in our analysis. We used three different station in the Techa: RT-1 in the higher Techa, RT-2 in the middle Techa, and RT-3 in lower Techa. As a control group was taken the fish from Miass river (RM station). Our results shows that perch from RT-3 (570.7 nm) significantly differ in coloration from the perch from RT-2 and RT-1 (p=0.00001 and p=0.0014 respectively, hereinafter used Kruskal-Wallis rank sum test with Nemenyi-Damico-Wolfe-Dunn test as post

  19. On the food of the Eurasian pygmy owl (Glaucidium passerinum) in Slovakia

    National Research Council Canada - National Science Library

    Karol Šotnár; Samuel Pačenovský; Ján Obuch

    2015-01-01

    Data on the food of the Eurasian pygmy owl in Slovakia was collected in 1999−2014 at 12 breeding locations in 7 mountain ranges of the Western Carpathian Mts and 1 range belonging to the Eastern Carpathian Mts...

  20. Henry E. Hale. Patronal Politics: Eurasian Regime Dynamics in Comparative Perspective

    OpenAIRE

    Thomas F. Remington

    2016-01-01

    Henry E. Hale. Patronal Politics: Eurasian Regime Dynamics in Comparative Perspective. Problems of International Politics. Eds. Keith Darden and Ian Shapiro. New York: Cambridge University Press, 2015. xviii, 542 pp. References. Index. US$39.99, paper.

  1. Biosystematic, molecular and phytochemical evidence for the multiple origin of sympetaly in Eurasian Sedoideae (Crassulaceae)

    NARCIS (Netherlands)

    't Hart, H; van Ham, RDHJ; Stevens, JF; Elema, ET; van der Klis, H; Gadella, TWJ

    Traditionally the sympetalous, Eurasian Crassulaceae are classified in four gen-era, but combined biosystematic, molecular and chemotaxonomic studies indicate that sympetaly evolved at least eight times independently in European Crassulaceae. Morphologically Umbilicus is very distinct and at the

  2. Pseudomine, an isoxazolidone with siderophoric activity from Pseudomonas fluorescens AH2 isolated from Lake Victorian Nile Perch

    DEFF Research Database (Denmark)

    Anthoni, U.; Christophersen, C.; Nielsen, P.H.

    1995-01-01

    A siderophore, pseudomonine, and sodium salicylate were isolated from the culture broth of iron-deficient cultures of Pseudomonas fluorescens AH2 isolated from the surface of spoiled Nile Perch from Lake Victoria......A siderophore, pseudomonine, and sodium salicylate were isolated from the culture broth of iron-deficient cultures of Pseudomonas fluorescens AH2 isolated from the surface of spoiled Nile Perch from Lake Victoria...

  3. Evading Invasives: How Eurasian Water-Milfoil Effects the Development of Lakefront Properties

    OpenAIRE

    Goodenberger, James; Klaiber, H. Allen

    2013-01-01

    Eurasian water-milfoil is an aquatic invasive plant that has moved rapidly through lakes across the United States. Along with being a hazard to local ecosystems, water-milfoil is a nuisance to those who use lakes for recreation, and its presence even lowers the value of lakefront properties. Though its effects can cause great disutility to lake users, no empirical studies have emerged that investigate the impacts that Eurasian water-milfoil, or any other invasive species, have on human behavi...

  4. Fish cell culture characteristics of a cell line from the silver perch Bairdiella chrysura.

    Science.gov (United States)

    Wharton, J H; Ellender, R D; Middlebrooks, B L; Stocks, P K; Lawler, A R; Howse, H D

    1977-06-01

    A cell designated SP-1 was established from tissue of the silver perch, Bairdiella chrysura. Cells were fibroblast-like and grew best at 26 degrees C in Leibovitz medium (L-15) containing 15% fetal bovine serum and 0.150 M sodium chloride. Passage 1 to passage 9 SP-1 cells contained a chromosome number of 48; at passages 27 and 50 the modal numbers were 51 and 54, respectively. Confirmation of the origin of SP-1 cells was made by the cytotoxic antibody dye-exclusion test. This cell line supported the growth of lymphocystis virus from the silver perch but was not found to replicate various other fish and mammalian viruses.

  5. Of paleo-genes and Perch: what if an "alien" is actually a native?

    Directory of Open Access Journals (Sweden)

    J Curt Stager

    Full Text Available Documenting whether a biotic taxon is native or alien to an ecosystem has theoretical value for ecological and evolutionary studies, and has practical value because it can potentially identify a taxon as a desirable component of an ecosystem or target it for removal. In some cases, however, such background information is inadequate or unavailable. Here we use paleo-DNA to re-evaluate the historical status of yellow perch in the 6 million acre Adirondack State Park of northern New York. Yellow perch DNA in a 2200-year sediment record reveals a long-term native status for these supposedly alien fish and challenges assumptions that they necessarily exclude native trout from upland lakes. Similar approaches could be applied to other species with uncertain historical distributions and could help to identify unrecognized pockets of biodiversity.

  6. Perch Selection by Three Cooccurring Species of Celithemis (Odonata: Libellulidae: Testing for a Competitive Hierarchy among Similar Species

    Directory of Open Access Journals (Sweden)

    Wade B. Worthen

    2016-01-01

    Full Text Available In many communities of perching dragonflies (Odonata: Libellulidae, a size-dependent competitive hierarchy creates a positive relationship between male body size and perch height. We tested for this pattern among three similar-sized species: Celithemis elisa, C. fasciata, and C. ornata. Males were caught and photographed from May to July 2015 at Ashmore Heritage Preserve, Greenville County, SC, USA, and perch heights and perch distance to open water were measured. Five indices of body size were measured with ImageJ software: abdomen length, forewing length, hindwing length, area of forewing, and area of hindwing. Celithemis fasciata was significantly larger than the other two species for all five anatomical characters and used perches that were significantly taller and closer to open water than the other species, though these differences changed over the summer. Aggressive interactions between and within species were tallied and compared to expected distributions based on mean relative abundances derived from hourly abundance counts. Patterns of interspecific aggression were also consistent with a size-dependent hierarchy: the large C. fasciata was attacked less frequently, and the small C. ornata more frequently, than predicted by their relative abundances. We conclude that even small differences in body size may contribute to niche partitioning in perch selection.

  7. Standardization of Clinical Assessment and Sample Collection Across All PERCH Study Sites.

    Science.gov (United States)

    Crawley, Jane; Prosperi, Christine; Baggett, Henry C; Brooks, W Abdullah; Deloria Knoll, Maria; Hammitt, Laura L; Howie, Stephen R C; Kotloff, Karen L; Levine, Orin S; Madhi, Shabir A; Murdoch, David R; O'Brien, Katherine L; Thea, Donald M; Awori, Juliet O; Bunthi, Charatdao; DeLuca, Andrea N; Driscoll, Amanda J; Ebruke, Bernard E; Goswami, Doli; Hidgon, Melissa M; Karron, Ruth A; Kazungu, Sidi; Kourouma, Nana; Mackenzie, Grant; Moore, David P; Mudau, Azwifari; Mwale, Magdalene; Nahar, Kamrun; Park, Daniel E; Piralam, Barameht; Seidenberg, Phil; Sylla, Mamadou; Feikin, Daniel R; Scott, J Anthony G

    2017-06-15

    Variable adherence to standardized case definitions, clinical procedures, specimen collection techniques, and laboratory methods has complicated the interpretation of previous multicenter pneumonia etiology studies. To circumvent these problems, a program of clinical standardization was embedded in the Pneumonia Etiology Research for Child Health (PERCH) study. Between March 2011 and August 2013, standardized training on the PERCH case definition, clinical procedures, and collection of laboratory specimens was delivered to 331 clinical staff at 9 study sites in 7 countries (The Gambia, Kenya, Mali, South Africa, Zambia, Thailand, and Bangladesh), through 32 on-site courses and a training website. Staff competency was assessed throughout 24 months of enrollment with multiple-choice question (MCQ) examinations, a video quiz, and checklist evaluations of practical skills. MCQ evaluation was confined to 158 clinical staff members who enrolled PERCH cases and controls, with scores obtained for >86% of eligible staff at each time-point. Median scores after baseline training were ≥80%, and improved by 10 percentage points with refresher training, with no significant intersite differences. Percentage agreement with the clinical trainer on the presence or absence of clinical signs on video clips was high (≥89%), with interobserver concordance being substantial to high (AC1 statistic, 0.62-0.82) for 5 of 6 signs assessed. Staff attained median scores of >90% in checklist evaluations of practical skills. Satisfactory clinical standardization was achieved within and across all PERCH sites, providing reassurance that any etiological or clinical differences observed across the study sites are true differences, and not attributable to differences in application of the clinical case definition, interpretation of clinical signs, or in techniques used for clinical measurements or specimen collection.

  8. Echolocation intensity and directionality of perching and flying fringe-lipped bats, Trachops cirrhosus (Phyllostomidae

    Directory of Open Access Journals (Sweden)

    Annemarie eSurlykke

    2013-06-01

    Full Text Available The Neotropical frog-eating bat, Trachops cirrhosus, primarily hunts stationary prey, either by gleaning on the wing, or in a sit-and-wait mode hanging from a perch. It listens passively for prey-generated sounds, but uses echolocation in all stages of the hunt. Like other bats in the family Phyllostomidae, T.cirrhosus has a conspicuous nose leaf, hypothesized to direct and focus echolocation calls emitted from the nostrils. T. cirrhosus is highly flexible in its cognitive abilities and its use of sensory strategies for prey detection. Additionally, T. cirrhosus has been observed to echolocate both with closed and open mouth. We hypothesize that its flexibility extends to echolocation call design. We investigated the effect of hunting mode, perching or flying, as well as the effect of mouth opening, on the acoustic parameters and directionality of the echolocation call. We used a multi-microphone array, a high-speed video camera, and a microphone-diode-video system to directly visualize the echolocation sound beam synchronized with the bat’s behavior. We found that T. cirrhosus emits a highly directional sound beam with HAM (half amplitude angle of 12o-18o and DI (directionality index of ~17 dB, among the most directional bat sonar beams measured to date. The directionality was high both when flying and when perching. The emitted intensity was low, around 88 dB SPL at10 cm from the mouth, when hanging, but higher, around 100 dB SPL at10 cm, when flying or just before take-off.Our data suggests that the limited search volume of T.cirrhosus’ sonar beam, defined by the high directionality and the rather low intensity of its echolocation calls, is adapted to the highly cluttered hunting habitat and to the perch hunting mode.

  9. Movements of yellow perch marked in southern Green Bay, Lake Michigan, in 1950

    Science.gov (United States)

    Mraz, Donald

    1952-01-01

    To obtain information on the post-spawning movements of yellow perch that spawn in southern Green Bay, Lake Michigan, 4,172 fish caught in drop nets were marked by tagging with monel-metal strap tags attached to the right operculum and 24,799 were marked by clipping off the second or membranous dorsal fin. Marking was done during the period from May 3 to 17, 1950, at six main stations, all located in the southern end of Green Bay.

  10. Hawk Eyes II: Diurnal Raptors Differ in Head Movement Strategies When Scanning from Perches

    OpenAIRE

    Colleen T O'Rourke; Todd Pitlik; Melissa Hoover; Esteban Fernández-Juricic

    2010-01-01

    BACKGROUND: Relatively little is known about the degree of inter-specific variability in visual scanning strategies in species with laterally placed eyes (e.g., birds). This is relevant because many species detect prey while perching; therefore, head movement behavior may be an indicator of prey detection rate, a central parameter in foraging models. We studied head movement strategies in three diurnal raptors belonging to the Accipitridae and Falconidae families. METHODOLOGY/PRINCIPAL FINDIN...

  11. Exploitation of Erythrina dominguezii Hassl. (Fabaceaenectar by perching birds in a dry forest in western Brazil

    Directory of Open Access Journals (Sweden)

    RAGUSA-NETTO J.

    2002-01-01

    Full Text Available Among the vertebrate pollinated plants, the genus Erythrina includes tree species in which birds are the pollen vectors. Two groups in this genus may be distinguished: a the hummingbird, and b the perching bird pollinated species. Erythrina dominguezii is included in the second group and occurs in deciduous/semi-deciduous forests in the southwestern neotropics. I studied the exploitation of Erythrina dominguezii nectar by perching birds in a dry forest in western Brazil. Six perching bird species from two distinct groups (Psittacidae: Brotogeris chiriri, Nandayus nenday, Aratinga acuticaudata; Icterinae: Psarocolius decumanus, Icterus cayanensis, I. icterus consumed its nectar. The two most important consumers were Brotogeris chiriri (51.5% of the flowers visited by birds and Psarocolius decumanus (20%. While B. chiriri was a flower predator, P. decumanus removed the nectar without damaging the flowers which it opened by inserting its large bill between the standard and the keel. Nandayus nenday, Aratinga acuticaudata, and I. icterus exploited the nectar like P. decumanus, and presumably also contributed to pollen transfer. As the flowering in E. dominguezii was intense and synchronous during the dryest period of the year, and its nectar was highly consumed by birds, the present data suggest that the nectar of this species may be important as an alternative resource to frugivorous/omnivorous birds when other resources are scarce.

  12. Exploitation of Erythrina dominguezii Hassl. (Fabaceaenectar by perching birds in a dry forest in western Brazil

    Directory of Open Access Journals (Sweden)

    J. RAGUSA-NETTO

    Full Text Available Among the vertebrate pollinated plants, the genus Erythrina includes tree species in which birds are the pollen vectors. Two groups in this genus may be distinguished: a the hummingbird, and b the perching bird pollinated species. Erythrina dominguezii is included in the second group and occurs in deciduous/semi-deciduous forests in the southwestern neotropics. I studied the exploitation of Erythrina dominguezii nectar by perching birds in a dry forest in western Brazil. Six perching bird species from two distinct groups (Psittacidae: Brotogeris chiriri, Nandayus nenday, Aratinga acuticaudata; Icterinae: Psarocolius decumanus, Icterus cayanensis, I. icterus consumed its nectar. The two most important consumers were Brotogeris chiriri (51.5% of the flowers visited by birds and Psarocolius decumanus (20%. While B. chiriri was a flower predator, P. decumanus removed the nectar without damaging the flowers which it opened by inserting its large bill between the standard and the keel. Nandayus nenday, Aratinga acuticaudata, and I. icterus exploited the nectar like P. decumanus, and presumably also contributed to pollen transfer. As the flowering in E. dominguezii was intense and synchronous during the dryest period of the year, and its nectar was highly consumed by birds, the present data suggest that the nectar of this species may be important as an alternative resource to frugivorous/omnivorous birds when other resources are scarce.

  13. Preferential flow, diffuse flow, and perching in an interbedded fractured-rock unsaturated zone

    Science.gov (United States)

    Nimmo, John R.; Creasey, Kaitlyn M; Perkins, Kimberlie; Mirus, Benjamin B.

    2017-01-01

    Layers of strong geologic contrast within the unsaturated zone can control recharge and contaminant transport to underlying aquifers. Slow diffuse flow in certain geologic layers, and rapid preferential flow in others, complicates the prediction of vertical and lateral fluxes. A simple model is presented, designed to use limited geological site information to predict these critical subsurface processes in response to a sustained infiltration source. The model is developed and tested using site-specific information from the Idaho National Laboratory in the Eastern Snake River Plain (ESRP), USA, where there are natural and anthropogenic sources of high-volume infiltration from floods, spills, leaks, wastewater disposal, retention ponds, and hydrologic field experiments. The thick unsaturated zone overlying the ESRP aquifer is a good example of a sharply stratified unsaturated zone. Sedimentary interbeds are interspersed between massive and fractured basalt units. The combination of surficial sediments, basalts, and interbeds determines the water fluxes through the variably saturated subsurface. Interbeds are generally less conductive, sometimes causing perched water to collect above them. The model successfully predicts the volume and extent of perching and approximates vertical travel times during events that generate high fluxes from the land surface. These developments are applicable to sites having a thick, geologically complex unsaturated zone of substantial thickness in which preferential and diffuse flow, and perching of percolated water, are important to contaminant transport or aquifer recharge.

  14. Mechanisms of Egg Yolk Formation and Implications on Early Life History of White Perch (Morone americana.

    Directory of Open Access Journals (Sweden)

    Justin Schilling

    Full Text Available The three white perch (Morone americana vitellogenins (VtgAa, VtgAb, VtgC were quantified accurately and precisely in the liver, plasma, and ovary during pre-, early-, mid-, and post-vitellogenic oocyte growth using protein cleavage-isotope dilution mass spectrometry (PC-IDMS. Western blotting generally mirrored the PC-IDMS results. By PC-IDMS, VtgC was quantifiable in pre-vitellogenic ovary tissues and VtgAb was quantifiable in pre-vitellogenic liver tissues however, neither protein was detected by western blotting in these respective tissues at this time point. Immunohistochemistry indicated that VtgC was present within pre-vitellogenic oocytes and localized to lipid droplets within vitellogenic oocytes. Affinity purification coupled to tandem mass spectrometry using highly purified VtgC as a bait protein revealed a single specific interacting protein (Y-box binding protein 2a-like [Ybx2a-like] that eluted with suramin buffer and confirmed that VtgC does not bind the ovary vitellogenin receptors (LR8 and Lrp13. Western blotting for LR8 and Lrp13 showed that both receptors were expressed during vitellogenesis with LR8 and Lrp13 expression highest in early- and mid-vitellogenesis, respectively. The VtgAa within the ovary peaked during post-vitellogenesis, while VtgAb peaked during early-vitellogenesis in both white perch and the closely related striped bass (M. saxatilis. The VtgC was steadily accumulated by oocytes beginning during pre-vitellogenesis and continued until post-vitellogenesis and its composition varies widely between striped bass and white perch. In striped bass, the VtgC accounted for 26% of the vitellogenin-derived egg yolk, however in the white perch it comprised only 4%. Striped bass larvae have an extended developmental window and these larvae have yolk stores that may enable them to survive in the absence of food for twice as long as white perch after hatch. Thus, the VtgC may play an integral role in providing nutrients to

  15. Mechanisms of Egg Yolk Formation and Implications on Early Life History of White Perch (Morone americana)

    Science.gov (United States)

    Schilling, Justin; Loziuk, Philip L.; Muddiman, David C.; Daniels, Harry V.; Reading, Benjamin J.

    2015-01-01

    The three white perch (Morone americana) vitellogenins (VtgAa, VtgAb, VtgC) were quantified accurately and precisely in the liver, plasma, and ovary during pre-, early-, mid-, and post-vitellogenic oocyte growth using protein cleavage-isotope dilution mass spectrometry (PC-IDMS). Western blotting generally mirrored the PC-IDMS results. By PC-IDMS, VtgC was quantifiable in pre-vitellogenic ovary tissues and VtgAb was quantifiable in pre-vitellogenic liver tissues however, neither protein was detected by western blotting in these respective tissues at this time point. Immunohistochemistry indicated that VtgC was present within pre-vitellogenic oocytes and localized to lipid droplets within vitellogenic oocytes. Affinity purification coupled to tandem mass spectrometry using highly purified VtgC as a bait protein revealed a single specific interacting protein (Y-box binding protein 2a-like [Ybx2a-like]) that eluted with suramin buffer and confirmed that VtgC does not bind the ovary vitellogenin receptors (LR8 and Lrp13). Western blotting for LR8 and Lrp13 showed that both receptors were expressed during vitellogenesis with LR8 and Lrp13 expression highest in early- and mid-vitellogenesis, respectively. The VtgAa within the ovary peaked during post-vitellogenesis, while VtgAb peaked during early-vitellogenesis in both white perch and the closely related striped bass (M. saxatilis). The VtgC was steadily accumulated by oocytes beginning during pre-vitellogenesis and continued until post-vitellogenesis and its composition varies widely between striped bass and white perch. In striped bass, the VtgC accounted for 26% of the vitellogenin-derived egg yolk, however in the white perch it comprised only 4%. Striped bass larvae have an extended developmental window and these larvae have yolk stores that may enable them to survive in the absence of food for twice as long as white perch after hatch. Thus, the VtgC may play an integral role in providing nutrients to late stage

  16. Winter survival of Eurasian woodcock Scolopax rusticola in central Italy

    Science.gov (United States)

    Aradis, A.; Miller, M.W.; Landucci, G.; Ruda, P.; Taddei, S.; Spina, F.

    2008-01-01

    The Eurasian woodcock Scolopax rusticola is a popular game bird in much of Europe. However, little is known about its population dynamics. We estimated winter survival of woodcock in a protected area with no hunting in central Italy. We radio-tagged 68 woodcocks with battery-powered radio-transmitters during 2001-2005. Woodcocks were captured in fields at night from November through February and fitted with radios. Birds were classified on capture as juveniles or adults using plumage characteristics. Woodcocks were relocated daily through March of each year or until they died, disappeared from the study area, or until their radio failed. We constructed a set of eight competing models of daily survival for the period 1 December - 28 February. Estimates of survival were obtained using the program SURVIV and Akaike's Information Criteria. The best model suggested daily survival was a constant 0.9985 (95% CI = 0.9972-0.9998), corresponding to a survival rate of 0.88 (SE = 0.05) for the 90-day winter study period. Our estimate of juvenile survival is higher than previously reported, and may reflect the protected status of the study area. Our estimates of winter survival may be helpful in managing harvested woodcock populations as well as in conserving populations in an increasingly urbanised environment. ?? Wildlife Biology (2008).

  17. Genotyping success of historical Eurasian lynx (Lynx lynx L.) samples.

    Science.gov (United States)

    Polanc, Primož; Sindičić, Magda; Jelenčič, Maja; Gomerčić, Tomislav; Kos, Ivan; Huber, Duro

    2012-03-01

    Historical samples, like tanned hides and trophy skulls, can be extremely important for genetic studies of endangered or elusive species. Selection of a sampling protocol that is likely to provide sufficient amount and quality of DNA with a minimum damage to the original specimen is often critical for a success of the study. We investigated microsatellite genotyping success of DNA isolated from three different types of Eurasian lynx historical samples. We analysed a total of 20 microsatellite loci in 106 historical samples from the endangered Dinaric lynx population, established from re-introduction of three pairs of lynx in 1973 from Slovakian Carpathians. Of the three tested sample types, turbinal bone and septum from the nasal cavity of the trophy skulls had the lowest percentage of samples successfully genotyped for all 20 microsatellite loci. Footpad samples, collected using a cork drill, exhibited better results in polymerase chain reaction amplification and genotyping than samples of footpad epidermis cut with a scalpel. We report simple and efficient sampling protocols, which could be widely applied for future studies utilizing historical samples. © 2011 Blackwell Publishing Ltd.

  18. A Preliminary Calibrated Deglaciation Chronology for the Eurasian Ice Complex

    Science.gov (United States)

    Tarasov, L.; Peltier, W. R.

    2006-12-01

    We present preliminary results for a high-resolution glaciologically-self-consistent deglacial history for the Eurasian ice complex calibrated against a large set of RSL data. The history is derived from on-going ensemble-based analyses using the 3D University of Toronto glacial systems model and a new high-resolution ice-margin chronology derived from geological and geomorphological observations. Isostatic response is computed with the VM2 viscosity structure. Bayesian calibration of the model is carried out using Markov Chain Monte Carlo methods in combination with neural networks trained to model results. The calibration provides a posterior distribution for model parameters (and thereby modelled glacial histories) given the observational data sets that thereby also takes into account data uncertainty. Comparison of the chronology against the current version of the ICE-5G deglacial load history will elucidate the impact of glaciological self-consistency on inferred load chronologies.A map of the computed present-day rate of vertical uplift will also be presented.

  19. Renal calculi in wild Eurasian otters (Lutra lutra) in England.

    Science.gov (United States)

    Simpson, V R; Tomlinson, A J; Molenaar, F M; Lawson, B; Rogers, K D

    2011-07-09

    Macroscopic renal calculi were seen in 50 of 492 (10.2 per cent) wild Eurasian otters found dead in England from 1988 to 2007. Forty-eight adults and two subadults were affected. Calculi were present in 15.7 per cent (31 of 197) of adult males and 12.7 per cent (17 of 134) of adult females. There was an increase in prevalence in the study population over time; no calculi were found in 73 otters examined between 1988 and 1996, but in most subsequent years they were observed with increased frequency. Calculi occurred in both kidneys but were more common in the right kidney. They varied greatly in shape and size; larger calculi were mostly seen in the calyces while the smallest ones were commonly found in the renal medulla. Calculi from 45 cases were examined by x-ray diffraction analysis; in 43 (96 per cent), they were composed solely of ammonium acid urate. Affected otters had heavier adrenal glands relative to their body size than unaffected otters (P0.05). Many otters had fresh bite wounds consistent with intraspecific aggression. The proportion bitten increased over time and this coincided with the increased prevalence of renal calculi.

  20. Integration Processes on Civil Service Reform in the Eurasian Space

    Directory of Open Access Journals (Sweden)

    George A. Borshevskiy

    2016-01-01

    Full Text Available In the article was studied the process of reforming the institute of civil service in the countries of the Eurasian space (e.g. Russia, Belarus and Kazakhstan. The integration of national systems of public administration and, in particular, the civil service, is an important factor contributing to the implementation of the centripetal tendencies in the post-Soviet space. The research methodology is based on a combination of comparative legal analysis, historical retrospective method, normalization and scaling, structural-functional and system analysis. A comparison of the legal models of public service was made in research. The author puts forward the hypothesis that it is presence the relationship between the quantitative changes (for example, number of employees of civil service and the dynamics of macroeconomic indicators (e.g. number of employed in the economy. In this regard were observed common trends. On materials of the statistical surveys were considered quantitative changes in national systems of civil service. The study of the socio-demographic characteristics of the public service (gender, age, profession allowed to formulate conclusions about the general and specific trends in the reform of the civil service of the analyzed countries. A number of values were first calculated by the author. The work is intended to become the basis for a broad international research on the development of civil service, which is the central mechanism for implementation the integration in the post-Soviet space.

  1. Quantifying the multiple, environmental benefits of reintroducing the Eurasian Beaver

    Science.gov (United States)

    Brazier, Richard; Puttock, Alan; Graham, Hugh; Anderson, Karen; Cunliffe, Andrew; Elliott, Mark

    2016-04-01

    Beavers are ecological engineers with an ability to modify the structure and flow of fluvial systems and create complex wetland environments with dams, ponds and canals. Consequently, beaver activity has potential for river restoration, management and the provision of multiple environmental ecosystem services including biodiversity, flood risk mitigation, water quality and sustainable drinking water provision. With the current debate surrounding the reintroduction of beavers into the United Kingdom, it is critical to monitor the impact of beavers upon the environment. We have developed and implemented a monitoring strategy to quantify the impact of reintroducing the Eurasian Beaver on multiple environmental ecosystem services and river systems at a range of scales. First, the experimental design and preliminary results will be presented from the Mid-Devon Beaver Trial, where a family of beavers has been introduced to a 3 ha enclosure situated upon a first order tributary of the River Tamar. The site was instrumented to monitor the flow rate and quality of water entering and leaving the site. Additionally, the impacts of beavers upon riparian vegetation structure, water/carbon storage were investigated. Preliminary results indicate that beaver activity, particularly the building of ponds and dams, increases water storage within the landscape and moderates the river response to rainfall. Baseflow is enhanced during dry periods and storm flow is attenuated, potentially reducing the risk of flooding downstream. Initial analysis of water quality indicates that water entering the site (running off intensively managed grasslands upslope), has higher suspended sediment loads and nitrate levels, than that leaving the site, after moving through the series of beaver ponds. These results suggest beaver activity may also act as a means by which the negative impact of diffuse water pollution from agriculture can be mitigated thus providing cleaner water in rivers downstream

  2. The Effect of Cooled Perches on Immunological Parameters of Caged White Leghorn Hens during the Hot Summer Months.

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    Rebecca A Strong

    Full Text Available The objective of this study was to determine if thermally cooled perches improve hen immunity during hot summer. White Leghorn pullets at 16 week of age were randomly assigned to 18 cages of 3 banks at 9 hens per cage. Each bank was assigned to 1 of the 3 treatments up to 32 week of age: 1 thermally cooled perches, 2 perches with ambient air, and 3 cages without perches. Hens were exposed to natural ambient temperatures from June through September 2013 in Indiana with a 4 h acute heat episode at 27.6 week of age. The packed cell volume, heterophil to lymphocyte (H/L ratio, plasma concentrations of total IgG, and cytokines of interleukin-1β and interleukin-6, plus lipopolysaccharide-induced tumor necrosis factor-α factor were measured at both 27.6 and 32 week of age. The mRNA expressions of these cytokines, toll-like receptor-4, and inducible nitric oxide synthase were also examined in the spleen of 32 week-old hens. Except for H/L ratio, thermally cooled perches did not significantly improve currently measured immunological indicators. These results indicated that the ambient temperature of 2013 summer in Indiana (24°C, 17.1 to 33.1°C was not high enough and the 4 h heat episode at 33.3°C (32 to 34.6°C was insufficient in length to evoke severe heat stress in hens. However, cooled perch hens had a lower H/L ratio than both air perch hens and control hens at 27.6 week of age and it was still lower compared to control hens (P < 0.05, respectively at 32 week of age. The lowered H/L ratio of cooled perch hens may suggest that they were able to cope with acute heat stress more effectively than control hens. Further studies are needed to evaluate the effectiveness of thermally cooled perches on hen health under higher ambient temperatures.

  3. First detection of Macrorhabdus ornithogaster in wild Eurasian Siskins (Carduelis spinus) in Germany. A case study.

    Science.gov (United States)

    Legler, M; Stelter, R; Jung, A; Wohlsein, P; Kummerfeld, N

    2015-01-01

    The colonization of the gastric ascomycetous yeast Macrorhabdus (M.) ornithogaster could be associated with a chronic wasting disease in several bird species in captivity. The prevalence and clinical relevance of M. ornithogaster in wild birds is unknown in detail. In the wintering season 2012/13 injured Eurasian Siskins (Carduelis spinus, n = 8) from the area of Hannover, Lower Saxony, Germany were examined microbiologically and pathologically. In six out of eight injured Eurasian Siskins M. ornithogaster were detected. The yeast was diagnosed microscopically in wet smears from the gastric isthmus and/or in faecal samples. Histopathological examination (n = 4) of the macroscopically slightly enlarged proventriculus in infected birds demonstrated the growth of M. ornithogaster in the mucosal surface and in the ducts of the glands without an inflammatory reaction. As a possible sign of a lowered fitness, all six infected siskins had a reduced body weight (mean: 11.8 ± 1.64 g) in the lower normal weight range compared to the two injured Eurasian Siskins without M. ornithogaster (15.0 g) as well as to data from the literature. Concurrent intestinal bacterial infections comprised Escherichia coli, Clostridium perfringens or Salmonella Typhimurium, that are regarded as an abnormal bacterial flora for Eurasian Siskins. Infections with M. ornithogaster can be found in the wild population of Eurasian Siskins in Germany. The frequent occurrence of secondary bacterial infections associated with M. ornithogaster infections should be considered in the treatment and rehabilitation of finches.

  4. The Eurasian otter (Lutra lutra) as a potential host for rickettsial pathogens in southern Italy.

    Science.gov (United States)

    Santoro, Mario; D'Alessio, Nicola; Cerrone, Anna; Lucibelli, Maria Gabriella; Borriello, Giorgia; Aloise, Gaetano; Auriemma, Clementina; Riccone, Nunzia; Galiero, Giorgio

    2017-01-01

    Canine monocytic ehrlichiosis and rickettsiosis are zoonotic tick-borne diseases of canids caused by the intracellular obligate bacteria Ehrlichia canis and Rickettsia species respectively. In this study, we investigated using standard and real-time PCR and sequencing, the occurrence and molecular characterization of E. canis and Rickettsia species in the Eurasian otter (Lutra lutra) from the southern Italian population. Samples were screened by using molecular assays also for Neospora caninum, Toxoplasma gondii, Clamydophyla spp., Coxiella burnetii, Leishmania spp., Cryptosporidium spp., and Giardia spp. detection, and helminths were studied by traditional methods. Out of six carcasses tested, three were positive for E. canis and co-infection with Rickettsia sp. occurred in one of those. Sequences of the 16S rRNA E. canis gene were identical to each other but differed from most of those previously found in red foxes (Vulpes vulpes) and wolves (Canis lupus) from southern Italy. Helminths included just cystacanths of Sphaerirostris spp. from the intestine of two Eurasian otters and the nematode Angiostrongylus vasorum from the lungs of a single Eurasian otter. None of the samples was positive for the other investigated selected pathogens. This study is the first report on the evidence of infection by rickettsial pathogens in the Eurasian otter. The present result prompts some inquiries into the pathogenic role of those bacteria for the isolated sub-populations of the endangered Eurasian otter in southern Italy.

  5. The Eurasian otter (Lutra lutra as a potential host for rickettsial pathogens in southern Italy.

    Directory of Open Access Journals (Sweden)

    Mario Santoro

    Full Text Available Canine monocytic ehrlichiosis and rickettsiosis are zoonotic tick-borne diseases of canids caused by the intracellular obligate bacteria Ehrlichia canis and Rickettsia species respectively. In this study, we investigated using standard and real-time PCR and sequencing, the occurrence and molecular characterization of E. canis and Rickettsia species in the Eurasian otter (Lutra lutra from the southern Italian population. Samples were screened by using molecular assays also for Neospora caninum, Toxoplasma gondii, Clamydophyla spp., Coxiella burnetii, Leishmania spp., Cryptosporidium spp., and Giardia spp. detection, and helminths were studied by traditional methods. Out of six carcasses tested, three were positive for E. canis and co-infection with Rickettsia sp. occurred in one of those. Sequences of the 16S rRNA E. canis gene were identical to each other but differed from most of those previously found in red foxes (Vulpes vulpes and wolves (Canis lupus from southern Italy. Helminths included just cystacanths of Sphaerirostris spp. from the intestine of two Eurasian otters and the nematode Angiostrongylus vasorum from the lungs of a single Eurasian otter. None of the samples was positive for the other investigated selected pathogens. This study is the first report on the evidence of infection by rickettsial pathogens in the Eurasian otter. The present result prompts some inquiries into the pathogenic role of those bacteria for the isolated sub-populations of the endangered Eurasian otter in southern Italy.

  6. Impacts of Snow Darkening by Absorbing Aerosols on Eurasian Climate

    Science.gov (United States)

    Kim, Kyu-Myong; Lau, William K M.; Yasunari, Teppei J.; Kim, Maeng-Ki; Koster, Randal D.

    2016-01-01

    The deposition of absorbing aerosols on snow surfaces reduces snow-albedo and allows snowpack to absorb more sunlight. This so-called snow darkening effect (SDE) accelerates snow melting and leads to surface warming in spring. To examine the impact of SDE on weather and climate during late spring and early summer, two sets of NASA GEOS-5 model simulations with and without SDE are conducted. Results show that SDE-induced surface heating is particularly pronounced in Eurasian regions where significant depositions of dust transported from the North African deserts, and black carbon from biomass burning from Asia and Europe occur. In these regions, the surface heating due to SDE increases surface skin temperature by 3-6 degrees Kelvin near the snowline in spring. Surface energy budget analysis indicates that SDE-induced excess heating is associated with a large increase in surface evaporation, subsequently leading to a significant reduction in soil moisture, and increased risks of drought and heat waves in late spring to early summer. Overall, we find that rainfall deficit combined with SDE-induced dry soil in spring provide favorable condition for summertime heat waves over large regions of Eurasia. Increased frequency of summer heat waves with SDE and the region of maximum increase in heat-wave frequency are found along the snow line, providing evidence that early snowmelt by SDE may increase the risks of extreme summer heat wave. Our results suggest that climate models that do not include SDE may significantly underestimate the effect of global warming over extra-tropical continental regions.

  7. Eurasian Union: A Utopia, a Dream or a Coming Reality?

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    Tuğçe Varol SEVIM

    2013-11-01

    Full Text Available Twenty years passed after the dissolution of the USSR and the re-birth of Russian Federation and Central Asian states in the world arena in such a unipolar world. Since the rise of Vladimir Putin to power Russia resists on unipolar system and sees that as a treat to its security. Hence, Kremlin perceives that the economic strength is the sine qua non for the future of Russia in order to sustain a Big Power status not only in its region but also in the world. In 2011, Russia, Belarus and Kazakhstan have achieved to form a Customs Union among them and invited all the states in the region to join the organization. There were thesis which mainly argued that Russia would no longer be a “power” in the Central Asia and could only be a regional power just in case of maintaining of its own unity. However, the circumstances have changed in the region accordingly Russian weight as a result of the new conjuncture. In 2012, Russia had a new presidential election and Putin returned to Kremlin as President himself. It has been understood from his words that Kremlin's new strategy to be focused on creating a Eurasian Union including Kyrgyzstan and Tajikistan at the first stage. It is aimed to analyze in this study that whether this project could be successful and if so, what could be the impacts on world order in terms of competition between Russia, the United States and China also. And finally, what could be the result of such an organization for the Russia.

  8. Application of fractional factorial design to improve hot smoked Nile Perch (Lates niloticus quality

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    Sokamté, T.A.

    2017-06-01

    Full Text Available The aim of this research was to study the parameters influencing moisture, salt and total phenol content of hot smoked Nile Perch and to compare the influence of processing conditions on its proximate composition and sensory quality. The effect on moisture, salt and total phenol content was investigated using fractional factorial design with seven factors and two levels: X1 for brine concentration, X2 for brining time, X3 for preliminary smoking-drying time, X4 for smoking time, X5 for hot smoking time, X6 for smoking temperature and X7 for hot smoking temperature. A Multiple Linear Regression Analysis was performed to fit the mathematical model to the collected data and the model tested using analysis of variance (ANOVA. Results of ANOVA indicated the good accuracy and highest significance of the mathematical model. The range of total protein and lipid content was 17.96 to 34.34% and 0.87 to 4.43%, respectively. The range of general acceptability of smoked Nile Perch was 4.6 to 8.2 based on 9-point hedonic scale. Based on the results obtained, including the overall acceptability, proximate composition and smoking criteria of finished product, samples produced with the following conditions: brining at 4% for 270min, drying at 30°C for 30min and the smoked time/temperature cycles following: 30°C/120min; 50°C/240min and 80°C/240min was the best and most accepted. The results derived from this study indicate that the fractional factorial design is a useful screening tool for improving industrial smoking process of Nile Perch.

  9. A new species of Leptorhynchoides Kostyler 1924 (Acanthocephala) from the pirate perch, Aphredoderus sayanus (Gilliams).

    Science.gov (United States)

    Buckner, R L; Buckner, S C

    1976-12-01

    Leptorhynchoides aphredoderi sp. n. is described from specimens recovered from pirate perch, Aphredoderus sayanus, collected in southeastern Louisiana. The new species is distinguished by having more longitudinal rows of proboscis hooks (15 to 18) than any other species of Leptorhynchoides. It differs additionally from L. thecatus and L. plagicephalus in having a shorter trunk, proboscis, proboscis receptacle, and proboscis hooks. Eggs of the new species are much larger than those of L. thecatus. L. aphredoderi differs further from L. plagicephalus in having fewer proboscis hooks in each longitudinal row and wider eggs. L. aphredoderi differs additionally from L. campbelli in having more proboscis hooks in each longitudinal row and much longer eggs.

  10. Improved COI barcoding primers for Southeast Asian perching birds (Aves: Passeriformes).

    Science.gov (United States)

    Lohman, David J; Prawiradilaga, Dewi M; Meier, Rudolf

    2009-01-01

    The All Birds Barcoding Initiative aims to assemble a DNA barcode database for all bird species, but the 648-bp 'barcoding' region of cytochrome c oxidase subunit I (COI) can be difficult to amplify in Southeast Asian perching birds (Aves: Passeriformes). Using COI sequences from complete mitochondrial genomes, we designed a primer pair that more reliably amplifies and sequences the COI barcoding region of Southeast Asian passerine birds. The 655-bp region amplified with these primers overlaps the COI region amplified with other barcoding primer pairs, enabling direct comparison of sequences with previously published DNA barcodes. © 2008 The Authors. Journal compilation © 2008 Blackwell Publishing Ltd.

  11. INVESTIGATIONS ON TECHNOLOGICAL PARAMETERS IN INTENSIVE REARING OF PIKE-PERCH (STIZOSTEDION LUCIOPERCA

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    Tamás Molnár

    2000-06-01

    Full Text Available Market demands and competition force the production of high quality freshwater fish in European aquaculture. In Hungary pike-perch is the most „noble” and perhaps the most sensitive fish species. One of the constraints of the increasing its production in natural waters, reservoirs and ponds is the shortage in adequate sized alevins. The possible solution of this problem can be the elaboration of intensive rearing technics of pond prereared fry. The aims of the present work were to test the growing capacity, feed conversion and survival of pike-perch in intensive circumstances. Fish were kept in 130 l aquaria working in recirculation system at an average water temperature of 220.5 C. Two stocking densities were applied (18 and 36 fish/aquarium. Minced fish (test and live prey (control were offered twice a day till satiation in two replications. The experiment lasted 4 weeks. According to our results minced fish is suitable feed in the intensive rearing of pike-perch alevins. Daily food intake was only influenced significantly by different feeds (2.01g vs.4.53 g, test and control, respectively. Feeding and stocking density had significant effect (P=0.001 and 0.017 on the average weight gain (0.52 g and 1.40 g for minced fish and live feed, respectively, 1.02 g in lower and 0.90 g in higher density. Owning to the high variances treatment effect on feed conversion proved to be not significant. Average survival of the minced fish fed group was 62.2 % vs. 78.8 % of the live fish fed alevins. This difference was significant (P<0.01 in the first two weeks when almost all of the losses happened due to cannibalism and other unknown reasons. Based on our results a period of 10–14 days is needed for pre-reared pike-perch to change gradually their feeding from zooplankton to minced fish diet.

  12. First evidence for carrion–feeding of Eurasian Eagle-owl (Bubo bubo in Bulgaria

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    Milchev Boyan

    2017-06-01

    Full Text Available Three cases of carrion-feeding with remains of artiodactyls (0.3%, n=1104 samples with food remains have been documented in a long term diet study of Eurasian Eagle-owls (Bubo bubo in 53 localities at Southeastern Bulgaria. Bone pieces of a sheep/goat (Ovis aries/Carpa hircus, a Fallow Deer (Dama dama and a Domestic Pig (Sus scrofa dom. in three Eurasian Eagle-owl breeding localities (5.7% prove extremely rare feeding on carrion. Northern White-breasted Hedgehog (Erinaceus roumanicus, rats (Rattus sp., waterbirds and gallinaceous birds (total 59.5-72.6% by biomass constituted the main portion of the diets with carrion remains. The comparisons between food niche breadths, diet composition, average prey biomass and values of superpredation of the annual diets in the three localities have not supported the carrion-feeding of the Eurasian Eagle-owl as a result of food shortages.

  13. Risk-taking by Eurasian lynx (Lynx lynx) in a human-dominated landscape : Effects of sex and reproductive status.

    NARCIS (Netherlands)

    Bunnefeld, N; Linnell, J.D C; Odden, J; van Duijn, M.A.J.; Andersen, R.A.

    This study aimed to test how the sex and reproductive status of Eurasian lynx influenced their use of 'attractive sinks' - habitats with high prey density and high mortality risks. Locations of 24 Eurasian lynx Lynx lynx were obtained by radio-telemetry in a mixed forest and agricultural habitat in

  14. Phylogenetic relationship of Eurasian lynx (Lynx lynx) revealed by complete mitochondrial genome.

    Science.gov (United States)

    Ning, Yao; Liu, Hui; Jiang, Guangshun; Ma, Jianzhang

    2016-09-01

    The Eurasian lynx (Lynx lynx) is an Endangered species in northeast China. We first obtained muscle sample, extracted the sample DNA and sequenced the whole mtDNA genome of lynx from northeast China. We reconstructed the phylogenetic tree of Eurasian lynx and 10 other most closely related Felidae species. This lynx's complete mitogenome is 17 054bp in length, includes 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and one control region. The phylogenetic tree confirmed previous research results.

  15. Normal haematological and serum biochemical values of Eurasian otters (Lutra lutra) from a Scottish rehabilitation centre.

    Science.gov (United States)

    Lewis, J C; Pagan, L; Hart, M; Green, R

    Blood samples were taken from 47 clinically normal, wild-born Eurasian otters (Lutra lutra) before they were released from a rehabilitation centre in Scotland between August 1990 and March 1996. Serum biochemistry profiles were determined for 47 animals and haematological profiles for 41, and the results from males, females, and animals under or over one year of age were analysed as separate groups and as pooled populations. The normal ranges for a wide variety of haematological and serum biochemical parameters of the Eurasian otter are presented, and significant differences with age and sex are detailed.

  16. Arctic moisture source for Eurasian snow cover variations in autumn

    Science.gov (United States)

    Wegmann, Martin; Orsolini, Yvan; Vázquez Dominguez, Marta; Gimeno Presa, Luis; Nieto, Raquel; Buligyna, Olga; Jaiser, Ralf; Handorf, Dörthe; Rinke, Anette; Dethloff, Klaus; Sterin, Alexander; Brönnimann, Stefan

    2015-04-01

    Global warming is enhanced at high northern latitudes where the Arctic surface air temperature has risen at twice the rate of the global average in recent decades - a feature called Arctic amplification. This recent Arctic warming signal likely results from several factors such as the albedo feedback due to a diminishing cryosphere, enhanced poleward atmospheric and oceanic transport, and change in humidity. The reduction in Arctic sea ice is without doubt substantial and a key factor. Arctic summer sea-ice extent has declined by more than 10% per decade since the start of the satellite era (e.g. Stroeve et al., 2012), culminating in a new record low in September 2012, with the long-term trend largely attributed to anthropogenic global warming. Eurasian snow cover changes have been suggested as a driver for changes in the Arctic Oscillation and might provide a link between sea ice decline in the Arctic during summer and atmospheric circulation in the following winter. However, the mechanism connecting snow cover in Eurasia to sea ice decline in autumn is still under debate. Our analysis focuses at sea ice decline in the Barents-Kara Sea region, which allows us to specify regions of interest for FLEXPART forward and backwards moisture trajectories. Based on Eularian and Lagrangian diagnostics from ERA-INTERIM, we can address the origin and cause of late autumn snow depth variations in a dense (snow observations from 820 land stations), unutilized observational datasets over the Commonwealth of Independent States. Open waters in the Barents and Kara Sea have been shown to increase the diabatic heating of the atmosphere, which amplifies baroclinic cyclones and might induce a remote atmospheric response by triggering stationary Rossby waves (Honda et al. 2009). In agreement with these studies, our results show enhanced storm activity originating at the Barents and Kara with disturbances entering the continent through a small sector from the Barents and Kara Seas

  17. Polychlorinated biphenyls in the Eurasian otter (Lutra lutra).

    Science.gov (United States)

    Smit, M D; Leonards, P E; de Jongh, A W; van Hattum, B G

    1998-01-01

    Several authors have suggested that contamination by polychlorinated biphenyls (PCBs) constitutes one of the major causes of the decline of the Eurasian otter (Lutra lutra) in large parts of Europe. This chapter provides an overview of available information regarding PCBs in European otters. Data on PCB concentrations in European otter tissues differ qualitatively among authors. Variations may be found in the organs used for analysis, the analytical method, and format of reported data (lipid weight vs. fresh weight, total PCB vs. congener-specific), which complicates a comparison of all data. Further, concentrations may be highly variable within an otter population, or even among individuals inhabiting the same area. Generally, average PCB levels in otters appear to be highest in areas where the species is in decline (mean levels ranging from 50 to 180 mg/kg fat) and thriving otter populations are correlated with low mean PCB tissue concentrations (mean levels less than 30 mg/kg fat). However, high levels have recently been found in thriving otter populations in Scotland, especially Shetland, leading some researchers to the conclusion that the alleged role of PCBs in the decline of the otter is likely to have been exaggerated. However, it is neither possible to dismiss the role of PCBs in the otter's decline as exaggerated nor to assume their important role as proven. The data presented in this review include information in support of both views. Most studies on PCBs in otters report total PCBs only, congener-specific data being quite rare. Information on levels of non-ortho congeners, the most toxic PCBs, is even more limited. Because congener patterns may vary between different otters, the total PCB concentration may not always be an accurate estimator of toxicity. To make a proper assessment of the impact of environmental PCB levels on the performance of otter populations and to establish "safe PCB levels" in sediment and fish, a number of toxicokinetic

  18. Approaches to the simulation of unconfined flow and perched groundwater flow in MODFLOW

    Science.gov (United States)

    Bedekar, Vivek; Niswonger, Richard G.; Kipp, Kenneth; Panday, Sorab; Tonkin, Matthew

    2012-01-01

    Various approaches have been proposed to manage the nonlinearities associated with the unconfined flow equation and to simulate perched groundwater conditions using the MODFLOW family of codes. The approaches comprise a variety of numerical techniques to prevent dry cells from becoming inactive and to achieve a stable solution focused on formulations of the unconfined, partially-saturated, groundwater flow equation. Keeping dry cells active avoids a discontinuous head solution which in turn improves the effectiveness of parameter estimation software that relies on continuous derivatives. Most approaches implement an upstream weighting of intercell conductance and Newton-Raphson linearization to obtain robust convergence. In this study, several published approaches were implemented in a stepwise manner into MODFLOW for comparative analysis. First, a comparative analysis of the methods is presented using synthetic examples that create convergence issues or difficulty in handling perched conditions with the more common dry-cell simulation capabilities of MODFLOW. Next, a field-scale three-dimensional simulation is presented to examine the stability and performance of the discussed approaches in larger, practical, simulation settings.

  19. Performance of free-range chickens reared in production modules enriched with shade net and perches

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    MJB Santos

    2014-03-01

    Full Text Available An experiment was carried out to evaluate the effect of environmental enrichment in a free-range chicken production system on live performance as a function of microclimate, physiological parameters, and performance parameters. Four production modules were divided into four pens with 10 birds each, totaling 60 birds. The following treatments were applied: access to a paddock (TEST, access to a paddock with perches (PER, access to a paddock with artificial shade (SHA, and access to the paddock with perches and artificial shade (PESH. The PESH production module presented the best globe temperature (Tbg,ºC and enthalpy (h, kJ/kg, and thereby, the best thermal environmental conditions, which ensured the longest permanence time of the birds in the paddock. The SHA and PESH modules promoted the lowest respiratory rate and shank and comb temperatures. Live performance was influenced by the presence of environmental enrichment (modules SHA and PESH, with the highest live weight (LW and weight gain (WG and the lowest feed conversion ratio (FCR and metabolizable energy intake (MEI. Parts yield, such as giblets, were not influenced by production modules, except for PESH, which promoted higher offal weight. In general, chickens reared in enriched production modules presented greatest performance and comfort results and were considered close to optimal rearing conditions.

  20. DEVELOPMENTS OF DIGESTIVE TRACT IN LARVAE OF CLIMBING PERCH, Anabas testudineus (Bloch

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    Yulintine Yulintine

    2010-12-01

    Full Text Available Climbing perch, Anabas testudineus (Bloch is a potential species for aquaculture in Kalimantan, Indonesia and belongs to Anabantidae family. The development of its digestive tract was evaluated on larvae reared under culture conditions of 28oC-30oC, from hatching to 30 days after hatching using histological and morphological methods. The larvae were kept in six 100-L tanks. They were fed with rotifers and microalgae from day 2nd after hatching to day 10th; Artemia nauplii from day 7th to day 15th; Artemia meta-nauplii from day 15th to day 20th; and Tubifex worm from day 20th onwards. The development of digestive tract in climbing perch followed the general pattern described for other species. Shortly after hatching, its digestive system was found to be consisted of an undifferentiated straight tube laying dorsally to the yolk sac. At first feeding (day 2nd, both mouth and anus had opened and the yolk sac was partially absorbed. On day 3, the digestive tract was fully differentiated into buccopharynx, esophagus, intestine and rectum. The two pyloric caeca appeared on day 25th after hatching, indicating the transition from larval to juvenile stage and acquisition of an adult type of digestion.

  1. Pan-Eurasian Experiment (PEEX): towards a holistic understanding of the feedbacks and interactions in the land-atmosphere-ocean-society continuum in the northern Eurasian region

    Science.gov (United States)

    Lappalainen, Hanna K.; Kerminen, Veli-Matti; Petäjä, Tuukka; Kurten, Theo; Baklanov, Aleksander; Shvidenko, Anatoly; Bäck, Jaana; Vihma, Timo; Alekseychik, Pavel; Andreae, Meinrat O.; Arnold, Stephen R.; Arshinov, Mikhail; Asmi, Eija; Belan, Boris; Bobylev, Leonid; Chalov, Sergey; Cheng, Yafang; Chubarova, Natalia; de Leeuw, Gerrit; Ding, Aijun; Dobrolyubov, Sergey; Dubtsov, Sergei; Dyukarev, Egor; Elansky, Nikolai; Eleftheriadis, Kostas; Esau, Igor; Filatov, Nikolay; Flint, Mikhail; Fu, Congbin; Glezer, Olga; Gliko, Aleksander; Heimann, Martin; Holtslag, Albert A. M.; Hõrrak, Urmas; Janhunen, Juha; Juhola, Sirkku; Järvi, Leena; Järvinen, Heikki; Kanukhina, Anna; Konstantinov, Pavel; Kotlyakov, Vladimir; Kieloaho, Antti-Jussi; Komarov, Alexander S.; Kujansuu, Joni; Kukkonen, Ilmo; Duplissy, Ella-Maria; Laaksonen, Ari; Laurila, Tuomas; Lihavainen, Heikki; Lisitzin, Alexander; Mahura, Alexsander; Makshtas, Alexander; Mareev, Evgeny; Mazon, Stephany; Matishov, Dmitry; Melnikov, Vladimir; Mikhailov, Eugene; Moisseev, Dmitri; Nigmatulin, Robert; Noe, Steffen M.; Ojala, Anne; Pihlatie, Mari; Popovicheva, Olga; Pumpanen, Jukka; Regerand, Tatjana; Repina, Irina; Shcherbinin, Aleksei; Shevchenko, Vladimir; Sipilä, Mikko; Skorokhod, Andrey; Spracklen, Dominick V.; Su, Hang; Subetto, Dmitry A.; Sun, Junying; Terzhevik, Arkady Y.; Timofeyev, Yuri; Troitskaya, Yuliya; Tynkkynen, Veli-Pekka; Kharuk, Viacheslav I.; Zaytseva, Nina; Zhang, Jiahua; Viisanen, Yrjö; Vesala, Timo; Hari, Pertti; Christen Hansson, Hans; Matvienko, Gennady G.; Kasimov, Nikolai S.; Guo, Huadong; Bondur, Valery; Zilitinkevich, Sergej; Kulmala, Markku

    2016-11-01

    The northern Eurasian regions and Arctic Ocean will very likely undergo substantial changes during the next decades. The Arctic-boreal natural environments play a crucial role in the global climate via albedo change, carbon sources and sinks as well as atmospheric aerosol production from biogenic volatile organic compounds. Furthermore, it is expected that global trade activities, demographic movement, and use of natural resources will be increasing in the Arctic regions. There is a need for a novel research approach, which not only identifies and tackles the relevant multi-disciplinary research questions, but also is able to make a holistic system analysis of the expected feedbacks. In this paper, we introduce the research agenda of the Pan-Eurasian Experiment (PEEX), a multi-scale, multi-disciplinary and international program started in 2012 (https://www.atm.helsinki.fi/peex/). PEEX sets a research approach by which large-scale research topics are investigated from a system perspective and which aims to fill the key gaps in our understanding of the feedbacks and interactions between the land-atmosphere-aquatic-society continuum in the northern Eurasian region. We introduce here the state of the art for the key topics in the PEEX research agenda and present the future prospects of the research, which we see relevant in this context.

  2. Pan-Eurasian Experiment (PEEX: towards a holistic understanding of the feedbacks and interactions in the land–atmosphere–ocean–society continuum in the northern Eurasian region

    Directory of Open Access Journals (Sweden)

    H. K. Lappalainen

    2016-11-01

    Full Text Available The northern Eurasian regions and Arctic Ocean will very likely undergo substantial changes during the next decades. The Arctic–boreal natural environments play a crucial role in the global climate via albedo change, carbon sources and sinks as well as atmospheric aerosol production from biogenic volatile organic compounds. Furthermore, it is expected that global trade activities, demographic movement, and use of natural resources will be increasing in the Arctic regions. There is a need for a novel research approach, which not only identifies and tackles the relevant multi-disciplinary research questions, but also is able to make a holistic system analysis of the expected feedbacks. In this paper, we introduce the research agenda of the Pan-Eurasian Experiment (PEEX, a multi-scale, multi-disciplinary and international program started in 2012 (https://www.atm.helsinki.fi/peex/. PEEX sets a research approach by which large-scale research topics are investigated from a system perspective and which aims to fill the key gaps in our understanding of the feedbacks and interactions between the land–atmosphere–aquatic–society continuum in the northern Eurasian region. We introduce here the state of the art for the key topics in the PEEX research agenda and present the future prospects of the research, which we see relevant in this context.

  3. First nearctic records for Orius (Dimorphella) sibiricus Wagner (Hemiptera: Heteroptera: Anthocoridae), a Eurasian steppe inhabitant

    Science.gov (United States)

    Orius sibiricus Wagner, a dark-colored minute pirate bug widespread in the Eurasian Steppe, is recorded from sites near the Yukon River in Yukon, Canada. This species is distinguished from the melanic phenotype of Orius diespeter Herring by the more deeply and uniformly punctured dorsum, the subangu...

  4. Ranging behaviour and socio-biology of Eurasian otters (Lutra lutra) on lowland mesotrophic river systems

    NARCIS (Netherlands)

    Neill, Lughaidh O.; Veldhuizen, Tijmen; de Jongh, Addy; Rochford, John

    We examined the spatial structure and sociobiology of a native wild population of Eurasian otters (Lutra lutra) on mesotrophic rivers in a mild temperate climate. Radio-tracking of 20 individuals revealed exclusive intra-sexual adult home-ranges. Adult female homeranges (7.5 km, SD = 1.5 km, n = 7)

  5. Selective Control of Eurasian Watermilfoil in Houghton Lake, Michigan: 2002-2006

    Science.gov (United States)

    2012-07-01

    Name Submersed Plants Bladderwort Utricularia vulgaris Coontail Ceratophyllum demersum Elodea Elodea canadensis Alpine pondweed Potamogeton...difficult or impossible to boat, swim, water ski , or fish in Eurasian watermilfoil-dominated areas. Interference with recrea- tion can result in a reduction

  6. Novel Eurasian Highly Pathogenic Influenza A H5 Viruses in Wild Birds, Washington, USA, 2014

    Centers for Disease Control (CDC) Podcasts

    2015-03-24

    Sarah Gregory reads an abridged version of the article, Novel Eurasian Highly Pathogenic Influenza A H5 Viruses in Wild Birds, Washington, USA, 2014.  Created: 3/24/2015 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 4/13/2015.

  7. Combinations of Endothall With 2,4-D and Triclopyr for Eurasian Watermilfoil Control

    Science.gov (United States)

    2010-04-01

    L., K. D. Getsinger, and A. B. Stewart. 1998. Selective effects of aquatic herbicides on sago pondweed. J. Aquat. Plant Manage. 36:64-68. Sprecher...Westerdahl, H. E., and J. F. Hall. 1983. Threshold 2,4-D concentrations for control of Eurasian watermilfoil and sago pondweed. J. Aquat. Plant

  8. Monitoring and assessment of conservation status of the Eurasian Otter (Lutra lutra) in Denmark

    DEFF Research Database (Denmark)

    Søgaard, Bjarne; Madsen, Aksel Bo; Elmeros, Morten

    initiated systematic monitoring of species in the Annex II and IV of the Directive – including the Eurasian Otter (Lutra lutra). The program focuses on monitoring distribution and range of the otter population in order to provide an assessment of its conservation status. The otter Lutra lutra suffered...

  9. A Eurasian Mineralogy: Aleksandr Fersman’s Conception of the Natural World.

    Science.gov (United States)

    Bruno, Andy

    2016-09-01

    Thoroughly a product of imperial Russia’s aristocratic culture, the mineralogist and geochemist Aleksandr Fersman rose to the top of the country’s scientific establishment after the Bolsheviks took control. He then remained a staunch supporter of various industrial projects through much of the Stalinist period. This essay puts Fersman’s thinking about the natural world in conversation with a quite distinctive mode of intellectual inquiry that developed contemporaneously. Eurasianism was a philosophical doctrine of a group of Russian émigrés who emphasized Russia’s unique status straddling Europe and Asia. While Fersman did not belong to this group of thinkers, a number of his ideas drew on specific experiences in the environments of the Eurasian landmass. Indeed, the article argues that Fersman’s dualistic understanding of nature, his advocacy for the field of geochemistry, his definition of deserts, and a scheme he proposed for industrial operations owed much to the Eurasian settings of the science he practiced. Furthermore, this case of a Eurasian mineralogist illuminates novel aspects of the interplay between national and global sciences.

  10. Dietary specialization during the evolution of Western Eurasian hominoids and the extinction of European Great Apes.

    Science.gov (United States)

    DeMiguel, Daniel; Alba, David M; Moyà-Solà, Salvador

    2014-01-01

    Given the central adaptive role of diet, paleodietary inference is essential for understanding the relationship between evolutionary and paleoenvironmental change. Here we rely on dental microwear analysis to investigate the role of dietary specialization in the diversification and extinction of Miocene hominoids from Western Eurasian between 14 and 7 Ma. New microwear results for five extinct taxa are analyzed together with previous data for other Western Eurasian genera. Except Pierolapithecus (that resembles hard-object feeders) and Oreopithecus (a soft-frugivore probably foraging opportunistically on other foods), most of the extinct taxa lack clear extant dietary analogues. They display some degee of sclerocarpy, which is most clearly expressed in Griphopithecus and Ouranopithecus (adapted to more open and arid environments), whereas Anoiapithecus, Dryopithecus and, especially, Hispanopithecus species apparently relied more strongly on soft-frugivory. Thus, contrasting with the prevailing sclerocarpic condition at the beginning of the Eurasian hominoid radiation, soft- and mixed-frugivory coexisted with hard-object feeding in the Late Miocene. Therefore, despite a climatic trend towards cooling and increased seasonality, a progressive dietary diversification would have occurred (probably due to competitive exclusion and increased environmental heterogeneity), although strict folivory did not evolve. Overall, our analyses support the view that the same dietary specializations that enabled Western Eurasian hominoids to face progressive climatic deterioration were the main factor ultimately leading to their extinction when more drastic paleoenvironmental changes took place.

  11. Dietary specialization during the evolution of Western Eurasian hominoids and the extinction of European Great Apes.

    Directory of Open Access Journals (Sweden)

    Daniel DeMiguel

    Full Text Available Given the central adaptive role of diet, paleodietary inference is essential for understanding the relationship between evolutionary and paleoenvironmental change. Here we rely on dental microwear analysis to investigate the role of dietary specialization in the diversification and extinction of Miocene hominoids from Western Eurasian between 14 and 7 Ma. New microwear results for five extinct taxa are analyzed together with previous data for other Western Eurasian genera. Except Pierolapithecus (that resembles hard-object feeders and Oreopithecus (a soft-frugivore probably foraging opportunistically on other foods, most of the extinct taxa lack clear extant dietary analogues. They display some degee of sclerocarpy, which is most clearly expressed in Griphopithecus and Ouranopithecus (adapted to more open and arid environments, whereas Anoiapithecus, Dryopithecus and, especially, Hispanopithecus species apparently relied more strongly on soft-frugivory. Thus, contrasting with the prevailing sclerocarpic condition at the beginning of the Eurasian hominoid radiation, soft- and mixed-frugivory coexisted with hard-object feeding in the Late Miocene. Therefore, despite a climatic trend towards cooling and increased seasonality, a progressive dietary diversification would have occurred (probably due to competitive exclusion and increased environmental heterogeneity, although strict folivory did not evolve. Overall, our analyses support the view that the same dietary specializations that enabled Western Eurasian hominoids to face progressive climatic deterioration were the main factor ultimately leading to their extinction when more drastic paleoenvironmental changes took place.

  12. Seeking explanations for recent changes in abundance of wintering Eurasian Wigeon (Anas penelope) in northwest Europe

    DEFF Research Database (Denmark)

    Fox, Anthony David; Dalby, Lars; Christensen, Thomas Kjær

    2016-01-01

    We analysed annual changes in abundance of Eurasian Wigeon (Anas penelope) derived from mid-winter International Waterbird Census data throughout its northwest European flyway since 1988 using log-linear Poisson regression modelling. Increases in abundance in the north and east of the wintering...

  13. Seasonal variation in Eurasian Wigeon Anas penelope sex and age ratios from hunter-based surveys

    DEFF Research Database (Denmark)

    Clausen, Kevin Kuhlmann; Dalby, Lars; Sunde, Peter

    2013-01-01

    schemes. This study found consistent seasonal variation in Eurasian Wigeon Anas penelope sex and age ratios among Danish hunter-based wing surveys, and describes how accounting for this variation might explain reported discrepancies between this and other monitoring methods. Early season flocks were...

  14. Evaluation of a New Biological Control Pathogen for Management of Eurasian Watermilfoil

    Science.gov (United States)

    2013-06-01

    reducing biodiversity . Its ability to grow at low temperatures allows it to quickly reach the water surface, forming a canopy that shades out other...Aquatic Plant Management Society. Gunner, H. B. 1983. Microbial control of Eurasian watermilfoil. Miscellaneous Paper A-83-4. Vicksburg, MS: U.S

  15. Eurasian golden jackal as host of canine vector-borne protists

    Czech Academy of Sciences Publication Activity Database

    Mitková, B.; Hrazdilová, K.; D'Amico, G.; Duscher, G. G.; Suchentrunk, F.; Forejtek, P.; Gherman, C.M.; Matei, I.A.; Ionică, A.M.; Daskalaki, A.A.; Mihalca, A. D.; Votýpka, Jan; Hulva, P.; Modrý, David

    2017-01-01

    Roč. 10, APR 14 (2017), č. článku 183. ISSN 1756-3305 Institutional support: RVO:60077344 Keywords : Eurasian golden jackal * Babesia * Hepatozoon * "Theileria annae" * Leishmania Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 3.080, year: 2016

  16. The formation of the Eurasian Economic Union: How successful is the Russian regional hegemony?

    Directory of Open Access Journals (Sweden)

    Ksenia Kirkham

    2016-07-01

    The novelty of the presentation of hegemony as an evolutionary process, which passes through initial, transitional and conclusive phases of its development, along with the recentness of the EAEU as a topic, could make this article a contribution to Eurasian integration studies.

  17. Estimating group size and population density of Eurasian badgers Meles meles by quantifying latrine use

    NARCIS (Netherlands)

    Tuyttens, F.A.M.; Long, B.; Fawcett, T.W.; Skinner, A.; Brown, J.A.; Cheeseman, C.L.; Roddam, A.W.; MacDonald, D.W.

    2001-01-01

    1. Conservation issues and a potential role in disease transmission generate the continued need to census Eurasian badgers Meles metes, but direct counts and sett counts present difficulties. The feasibility of estimating social group size and population density of badgers by quantifying their use

  18. Song repertoire size correlates with measures of body size in Eurasian blackbirds

    DEFF Research Database (Denmark)

    Hesler, Nana; Mundry, Roger; Sacher, Thomas

    2012-01-01

    In most oscine bird species males possess a repertoire of different song patterns. The size of these repertoires is assumed to serve as an honest signal of male quality. The Eurasian blackbird’s (Turdus merula) song contains a large repertoire of different element types with a flexible song organ...

  19. Current distribution and habitat preferences of red deer and eurasian elk in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Dušan Romportl

    2017-06-01

    Full Text Available Here we determine the distribution, numbers and habitat preferences of two of the largest species in the family Cervidae present in the Czech Republic, red deer and Eurasian elk. Red deer occurs predominantly in vast areas of forest, i.e. mainly in the mountains bordering this country and several large forest units in the interior. The range of this species has been increasing along with the size of its population. Areas of its permanent occurrence may be generally characterized as regions largely covered with deciduous and coniferous forests and pastures, and regions with a more diverse landscape. Red deer does not occur in areas that are mainly arable or urban, or in areas covered with extensive water bodies and wetlands. As these animals prefer large forests, they occur mainly at high altitudes where the terrain is rugged. The Eurasian elk permanently occurs in the Czech Republic in a single area located between the state border and the right bank of the Lipno Dam. Its home range has been diminishing, presumably along with its numbers. The area of its permanent occurrence is characterized by an abundance of coniferous trees, some pastures and water bodies. The Eurasian elk does not occur in areas covered with arable and urban land but also surprisingly in areas with mainly deciduous forest. Both species prefer high altitudes, but Eurasian elk prefers areas with little difference in the terrain vertically.

  20. Unraveling the biogeographic origins of the Eurasian watermilfoil (Myriophyllum spicatum) invasion in North America.

    Science.gov (United States)

    Moody, Michael L; Palomino, Nayell; Weyl, Philip S R; Coetzee, Julie A; Newman, Raymond M; Harms, Nathan E; Liu, Xing; Thum, Ryan A

    2016-04-01

    Using phylogeographic analyses to determine the geographic origins of biological invaders is important for identifying environmental adaptations and genetic composition in their native range as well as biocontrol agents among indigenous herbivores. Eurasian watermilfoil (Myriophyllum spicatum) and its hybrid with northern watermilfoil (M. sibiricum) are found throughout the contiguous United States and southern Canada, forming one of the most economically costly aquatic plant invasions in North America, yet the geographic origin of the invasion remains unknown. The objectives of our study included determining the geographic origin of Eurasian watermilfoil in North America as well as the maternal lineage of the hybrids. DNA sequence data from a cpDNA intron and the nrDNA ITS region were compiled for accessions from 110 populations of Eurasian watermilfoil and hybrids from North America and the native range (including Europe, Asia, and Africa). Datasets were analyzed using statistical parsimony and Bayesian phylogenetics to assess the geographic origin of the invasion. The two Eurasian watermilfoil cpDNA haplotypes in North America are also found from China and Korea, but not elsewhere in the native range. These haplotypes did not overlap and were limited in native geographic range. The ovule parent for hybrids can come from either parental lineage, and multiple haplotypes from both parental species were found. The geographic origin of this prolific aquatic plant invasion of North America is in Asia. This provides critical information to better understand the invasion pathway and inform management into the future. © 2016 Botanical Society of America.

  1. Yellow perch embryo-larval survival and growth in surface waters associated with oil-sands mining

    Energy Technology Data Exchange (ETDEWEB)

    Peters, L.E.; Heuvel, M.R. van den; Dixon, D.G. [Univ. of Waterloo, Ontario (Canada); Power, M. [Univ. of Manitoba, Winnipeg, Manitoba (Canada); Boerger, H.; MacKinnon, M.D.; Meer, T. Van [Syncrude Canada, Fort McMurray, Alberta (Canada)

    1995-12-31

    As part of their land reclamation strategy, Syncrude Canada Ltd. is currently developing environmentally acceptable tailings disposal methods. Fine tailings, a suspension of clay and residual bitumen, is the waste product from oil sands extraction. Fine-tailings contain naphthenic acids, a group of saturated aliphatic and alicyclic carboxylic acids, which occur naturally in petroleum and are partly responsible for the toxicity of process water. The wet landscape method involves covering fine tails with a layer of water such that a self-sustaining ecosystem can be established. A 5 ha demonstration pond with a bottom of fine-tailings was constructed and stocked with yellow perch for experimental purposes. Two other reclaimed ponds formed with oil-sands overburden material were also stocked with perch. Adult perch sampled in the fall of 1995 from the experimental and reclaimed ponds exhibited a 2-fold induction of MFO activity compared to the source lake; indicating organic compound exposure. Perch from one of the reclaimed ponds showed significantly reduced circulating reproductive hormone levels, gonad size and smaller ovarian follicles. Reproductive parameters were not different between the source lake and the remaining ponds. Paired lab and field experiments were conducted to determine if contaminants present would be detrimental to egg viability and development of larvae either through direct exposure of spawned eggs or indirectly by effecting oogenesis. An early life stage toxicity test was also performed using commercially available naphthenic acid standard. Endpoints measured were percent fertilization, percent hatch, mortality, deformities, timing of developmental periods and larval growth.

  2. Chequered fortunes in global exports: The sociogenesis of African entrepreneurship in the Nile Perch Business at Lake Victoria, Uganda

    NARCIS (Netherlands)

    Beuving, J.J.

    2013-01-01

    This article looks at African entrepreneurship in the Nile perch export business at Lake Victoria, Uganda. Often heralded as an economic success story, this business has perhaps another tale to tell. The fishermen, traders and other small-scale entrepreneurs at the lower end of the export chain face

  3. Chad Genetic Diversity Reveals an African History Marked by Multiple Holocene Eurasian Migrations.

    Science.gov (United States)

    Haber, Marc; Mezzavilla, Massimo; Bergström, Anders; Prado-Martinez, Javier; Hallast, Pille; Saif-Ali, Riyadh; Al-Habori, Molham; Dedoussis, George; Zeggini, Eleftheria; Blue-Smith, Jason; Wells, R Spencer; Xue, Yali; Zalloua, Pierre A; Tyler-Smith, Chris

    2016-12-01

    Understanding human genetic diversity in Africa is important for interpreting the evolution of all humans, yet vast regions in Africa, such as Chad, remain genetically poorly investigated. Here, we use genotype data from 480 samples from Chad, the Near East, and southern Europe, as well as whole-genome sequencing from 19 of them, to show that many populations today derive their genomes from ancient African-Eurasian admixtures. We found evidence of early Eurasian backflow to Africa in people speaking the unclassified isolate Laal language in southern Chad and estimate from linkage-disequilibrium decay that this occurred 4,750-7,200 years ago. It brought to Africa a Y chromosome lineage (R1b-V88) whose closest relatives are widespread in present-day Eurasia; we estimate from sequence data that the Chad R1b-V88 Y chromosomes coalesced 5,700-7,300 years ago. This migration could thus have originated among Near Eastern farmers during the African Humid Period. We also found that the previously documented Eurasian backflow into Africa, which occurred ∼3,000 years ago and was thought to be mostly limited to East Africa, had a more westward impact affecting populations in northern Chad, such as the Toubou, who have 20%-30% Eurasian ancestry today. We observed a decline in heterozygosity in admixed Africans and found that the Eurasian admixture can bias inferences on their coalescent history and confound genetic signals from adaptation and archaic introgression. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  4. Haematology and Serum Biochemistry Parameters and Variations in the Eurasian Beaver (Castor fiber.

    Directory of Open Access Journals (Sweden)

    Simon J Girling

    Full Text Available Haematology parameters (N = 24 and serum biochemistry parameters (N = 35 were determined for wild Eurasian beavers (Castor fiber, between 6 months - 12 years old. Of the population tested in this study, N = 18 Eurasian beavers were from Norway and N = 17 originating from Bavaria but now living extensively in a reserve in England. All blood samples were collected from beavers via the ventral tail vein. All beavers were chemically restrained using inhalant isoflurane in 100% oxygen prior to blood sampling. Results were determined for haematological and serum biochemical parameters for the species and were compared between the two different populations with differences in means estimated and significant differences being noted. Standard blood parameters for the Eurasian beaver were determined and their ranges characterised using percentiles. Whilst the majority of blood parameters between the two populations showed no significant variation, haemoglobin, packed cell volume, mean cell haemoglobin and white blood cell counts showed significantly greater values (p<0.01 in the Bavarian origin population than the Norwegian; neutrophil counts, alpha 2 globulins, cholesterol, sodium: potassium ratios and phosphorus levels showed significantly (p<0.05 greater values in Bavarian versus Norwegian; and potassium, bile acids, gamma globulins, urea, creatinine and total calcium values levels showed significantly (p<0.05 greater values in Norwegian versus Bavarian relict populations. No significant differences were noted between male and female beavers or between sexually immature (<3 years old and sexually mature (≥3 years old beavers in the animals sampled. With Eurasian beaver reintroduction encouraged by legislation throughout Europe, knowledge of baseline blood values for the species and any variations therein is essential when assessing their health and welfare and the success or failure of any reintroduction program. This is the first study to produce

  5. Biogenic volatile organic compound emissions from the Eurasian taiga: current knowledge and future directions

    Energy Technology Data Exchange (ETDEWEB)

    Rinne, J. (Dept. of Physics, Univ. of Helsinki (Finland)); Baeck, J. (Dept. of Forest Ecology, Univ. of Helsinki (Finland)); Hakola, H. (Finnish Meteorological Institute, Air Quality Research, Helsinki (Finland))

    2009-07-01

    n this paper, the research conducted on the emissions of the biogenic volatile organic compounds (BVOCs) from the European boreal zone, or taiga, is reviewed. We highlight the main findings and the key gaps in our knowledge. Ecosystem scale BVOC emissions from the Eurasian taiga are observed to be relatively low as compared with those from some forest ecosystems in warmer climates. One of the distinctive features of the Eurasian taiga is the predominance of monoterpene emitting coniferous trees. Recent research indicates that in addition to evaporation from storage structures, part of the monoterpene emission of conifers originates directly from synthesis. Monoterpene emission from boreal deciduous trees originates mainly directly from synthesis. The boreal trees exhibit distinct intra-species variation in the monoterpene mixtures they emit. Important sources of isoprene in the Eurasian taiga include Norway spruce, open wetland ecosystems and some non-dominant woody species, such as European aspen and willows. Many boreal tree species also emit non-terpenoid compounds and highly reactive sesquiterpenes. The future challenges in the research on BVOC emissions from the Eurasian taiga include (i) quantification and understanding the non-terpenoid VOC emissions from the taiga ecosystems, (ii) bringing ecosystems in the eastern Eurasian taiga into the sphere of BVOC emission studies, (iii) establishing long-term ecosystem flux studies combined with plant physiological measurements, and (iv) integrating knowledge and research skills on BVOC synthesis, storages and emissions, land cover changes and atmospheric processes in different spatial and temporal scales in order to better understand the impact of biosphere on atmospheric chemistry and composition in changing climate. (orig.)

  6. Genetic evidence of successful establishment of the Nile perch (Lates spp. L. in East African lakes and implications for management

    Directory of Open Access Journals (Sweden)

    Matthew Tenywa Mwanja

    2012-12-01

    Full Text Available Nile perch establishment in novel ranges in East Africa is one of the most successful freshwater invasion stories in the recent history. Itbecame ecologically dominant and well established in several lakes in the Lake Victoria Region in a period of less than 5 decades. Geneticdiversity of both introduced and native populations were assessed and patterns compared in order to establish the genetic consequences oftheir introductions. Genetic variation was surveyed at both the mitochondrial control region (CR and at nine microsatellite loci. A total of 527 Nile perch fish were sampled from 5 East African lakes: native source populations were examined from lakes Albert and Turkana while introduced populations were sampled from lakes Kyoga, Nabugabo and Victoria. Both types of markers revealed higher average geneticdiversity for invasive species (HE = 0.70, h = 0.81 than for native source populations (HE = 0.66, h = 0.69. Both populations scoredrelatively higher than the average for freshwater fishes (HE = 0.62. Both native and introduced populations had 2 underlying geneticgroupings in similar proportions as revealed by the STRUCTURE program. The high genetic diversity was most probably a consequence ofhigher numbers of propagules than outlined by official records of introductions. Use of high number of individuals at stocking is probably the reason for apparently minimized ‘founder effects’ of Nile perch in the introduced ranges. The two underling populations revealed through genetic analysis may be representatives of the two subspecies of Nile perch previously reported in other studies. Implications to the management of this fishery in the East African region is that with the relatively high genetic diversity, the species could be sustainably exploited if it were effectively managed. In addition, further studies of the life histories and other attributes of the two genetic groupings of Nile perch in the region are recommended, as they may

  7. Tropical fish in a warming world: thermal tolerance of Nile perch Lates niloticus (L.) in Lake Nabugabo, Uganda.

    Science.gov (United States)

    Chrétien, Emmanuelle; Chapman, Lauren J

    2016-01-01

    Key to predicting the response of fishes to climate change is quantifying how close fish are to their critical thermal limits in nature and their ability to adjust their thermal sensitivity to maintain performance. Here, we evaluated the effects of body size and habitat on aerobic scope (AS) and thermal tolerance of Nile perch Lates niloticus (L.), a fish of great economic and food security importance in East Africa, using respirometry and critical thermal maximum (CTmax) trials. Juvenile Nile perch from distinct habitats (high or low dissolved oxygen concentrations) of Lake Nabugabo, Uganda were exposed for 4.6 ± 0.55 days to a temperature treatment (25.5, 27.5, 29.5 or 31.5°C) prior to experimentation, with the lowest temperature corresponding to the mean annual daytime temperature in Lake Nabugabo and the highest temperature being 3°C higher than the maximal monthly average. As expected, metabolic rates increased with body mass. Although resting metabolic rate increased with temperature, maximal metabolic rate showed no change. Likewise, AS did not vary across treatments. The CTmax increased with acclimation temperature. There was no effect of habitat on maximal metabolic rate, AS or CTmax; however, there was a trend towards a lower resting metabolic rate for Nile perch captured in the low-dissolved oxygen habitat than in well-oxygenated waters. This study shows that juvenile Nile perch maintain a large AS at temperatures near the upper limit of their natural thermal range and provides evidence that Nile perch have physiological mechanisms to deal with acute exposure to thermal stress.

  8. Lipophilic antioxidants and lipid peroxidation in yellow perch subjected to various anthropogenic influences along the St. Lawrence River (QC, Canada).

    Science.gov (United States)

    Landry, Catherine; Houde, Magali; Brodeur, Philippe; Spear, Philip; Boily, Monique

    2017-05-01

    In Lake Saint-Pierre (LSP), the last great widening of the St. Lawrence River (province of Québec, Canada), the yellow perch has been experiencing a significant decline since the mid-1990s. The combined effect of several stressors (deterioration of habitats appropriate for reproduction and growth, invasive species and poor water quality) seems to exert considerable influence on the yellow perch population in LSP, characterized by low recruitment. To better understand possible stressor effects at the biochemical level, LSP yellow perch were compared with other sites along a gradient of increasing human influences from upstream to downstream along the St. Lawrence River. Morphometry (size, weight, circumference and Fulton's condition factor) and biomarkers associated to the peroxidation of lipids, lipophilic antioxidants (α-tocopherol and carotenoids), along with retinoids (vitamins A1and A2) and proteins were compared between sites at the larval, juvenile and adult stages. Fulton's condition factor was similar between sites for juveniles but was significantly lower in LSP adults, suggesting a weakened physiological condition. In most contaminated sites as LSP, lipid peroxidation tended to be higher in juveniles and adults whereas the lipophilic antioxidant lycopene and proteins content were lower. Retinyl esters were significantly lower for LSP fish compared to other sites, not only in larvae but also in the livers of juveniles and adults. These results are consistent with possible altered metabolism in the retinoid system of LSP yellow perch. The overall results reflect the "pressure" gradient tested, where the yellow perch from the most affected sites located downstream had impaired physiological and biochemical conditions compared to the upstream sectors. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. PERCH in Perspective: What Can It Teach Us About Pneumonia Etiology in Children?

    Science.gov (United States)

    Klugman, Keith P; Rodgers, Gail L

    2017-06-15

    The pneumonia team at the Bill & Melinda Gates Foundation congratulates the Pneumonia Etiology Research for Child Health (PERCH) study on delivering on their grant to collect high-quality data from thousands of children with World Health Organization-defined severe and very severe pneumonia and from controls in 9 diverse sites in 7 low- and middle-income countries. This supplement sets the foundation to understanding this complex study by providing an in-depth description of the study methodology, including discussion of key aspects such as antibiotic pretreatment, chest radiograph interpretation, utility of induced sputum in children, measurement of pathogen density, and use of C-reactive protein, and how these affect pneumonia etiology. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

  10. Hawk eyes II: diurnal raptors differ in head movement strategies when scanning from perches.

    Science.gov (United States)

    O'Rourke, Colleen T; Pitlik, Todd; Hoover, Melissa; Fernández-Juricic, Esteban

    2010-09-22

    Relatively little is known about the degree of inter-specific variability in visual scanning strategies in species with laterally placed eyes (e.g., birds). This is relevant because many species detect prey while perching; therefore, head movement behavior may be an indicator of prey detection rate, a central parameter in foraging models. We studied head movement strategies in three diurnal raptors belonging to the Accipitridae and Falconidae families. We used behavioral recording of individuals under field and captive conditions to calculate the rate of two types of head movements and the interval between consecutive head movements. Cooper's Hawks had the highest rate of regular head movements, which can facilitate tracking prey items in the visually cluttered environment they inhabit (e.g., forested habitats). On the other hand, Red-tailed Hawks showed long intervals between consecutive head movements, which is consistent with prey searching in less visually obstructed environments (e.g., open habitats) and with detecting prey movement from a distance with their central foveae. Finally, American Kestrels have the highest rates of translational head movements (vertical or frontal displacements of the head keeping the bill in the same direction), which have been associated with depth perception through motion parallax. Higher translational head movement rates may be a strategy to compensate for the reduced degree of eye movement of this species. Cooper's Hawks, Red-tailed Hawks, and American Kestrels use both regular and translational head movements, but to different extents. We conclude that these diurnal raptors have species-specific strategies to gather visual information while perching. These strategies may optimize prey search and detection with different visual systems in habitat types with different degrees of visual obstruction.

  11. Hawk eyes II: diurnal raptors differ in head movement strategies when scanning from perches.

    Directory of Open Access Journals (Sweden)

    Colleen T O'Rourke

    Full Text Available BACKGROUND: Relatively little is known about the degree of inter-specific variability in visual scanning strategies in species with laterally placed eyes (e.g., birds. This is relevant because many species detect prey while perching; therefore, head movement behavior may be an indicator of prey detection rate, a central parameter in foraging models. We studied head movement strategies in three diurnal raptors belonging to the Accipitridae and Falconidae families. METHODOLOGY/PRINCIPAL FINDINGS: We used behavioral recording of individuals under field and captive conditions to calculate the rate of two types of head movements and the interval between consecutive head movements. Cooper's Hawks had the highest rate of regular head movements, which can facilitate tracking prey items in the visually cluttered environment they inhabit (e.g., forested habitats. On the other hand, Red-tailed Hawks showed long intervals between consecutive head movements, which is consistent with prey searching in less visually obstructed environments (e.g., open habitats and with detecting prey movement from a distance with their central foveae. Finally, American Kestrels have the highest rates of translational head movements (vertical or frontal displacements of the head keeping the bill in the same direction, which have been associated with depth perception through motion parallax. Higher translational head movement rates may be a strategy to compensate for the reduced degree of eye movement of this species. CONCLUSIONS: Cooper's Hawks, Red-tailed Hawks, and American Kestrels use both regular and translational head movements, but to different extents. We conclude that these diurnal raptors have species-specific strategies to gather visual information while perching. These strategies may optimize prey search and detection with different visual systems in habitat types with different degrees of visual obstruction.

  12. Eurasian winter cooling in the warming hiatus of 1998-2012

    Science.gov (United States)

    Li, C.; Stevens, B. B.; Marotzke, J.

    2016-02-01

    In this study, we investigated the relative magnitudes of the contributions of surface temperature trends from different latitude bands to the recent warming hiatus. We confirm from five different global datasets that the global-mean surface temperature trend in the period 1998—2012 is strongly influenced by a pronounced Eurasian winter cooling trend. This cooling trend was not reproduced in an influential model study attributing most of the hiatus to cooling in the tropical Pacific (Kosaka and Xie, 2013) and hence might have different causes. Arctic sea ice loss over interannual time scales has previously been shown to influence Eurasian winter temperatures (Kim et al., 2014; Mori et al., 2014), but whether such an influence exists for the concrete hiatus period has remained unclear. To understand the drivers of this winter-cooling trend, we perform three twenty-member ensembles of simulations with different prescribed sea surface temperature and sea ice in the atmospheric model ECHAM6. Our experimental results suggest that the Arctic sea-ice loss does not drive systematic changes in the northern-hemisphere large-scale circulation in the past decades. The observed Eurasian winter cooling trend over 1998-2012 arises essentially from atmospheric internal variability and constitutes an extreme climate event. However, the observed reduction in Arctic sea ice enhances the variability of Eurasian winter climate and thus increases the probability of an extreme Eurasian winter cooling trend. Reference: Kosaka, Y., and S.-P. Xie, 2013: Recent global-warming hiatus tied to equatorial Pacific surface cooling. Nature, 501, 403—407. Kim, B. M., S. W. Son, S. K. Min, J. H. Jeong, S. J. Kim, X. D. Zhang, T. Shim and J. H. Yoon, 2014: Weakening of the stratospheric polar vortex by Arctic sea-ice loss, Nature Communications, doi:10.1038/ncomms5646. Mori M., M. Watanabe, H. Shiogama, J. Inoue, and M. Kimoto, 2014: Robust Arctic sea-ice inuence on the frequent Eurasian cold

  13. Eurasian Economic Union and Prospects of Development of Transnational Corporations in the Frame of the Globalization

    Directory of Open Access Journals (Sweden)

    Anatoliy Tikhonovitch Spitsyn

    2016-09-01

    Full Text Available The purpose of this article is to study the processes of regional integration and its particular features in the frame of the Eurasian Economic Union formation and their impact on the development of transnational corporations in the region. The authors used the scientific and methodological basis including an integrated approach and economic, institutional and organizational methods, theoretical and methodological studies of domestic and foreign scientists. In order to achieve the defined aim of this research, the authors used the retrospective method and method of comparative analysis, studied the statistical data, including the reports of the United Nations Conference on Trade and Development and the World Bank’s ratings. The authors studied the historical background of the Eurasian Economic Union, analyzed the current economic situation in its Member States, and considered the experience of other regional alliances. According to the results of the research, the authors formulated the conclusions in the context of the most likely prospects for the development of transnational corporations in the frame of the integration of the Member States of the Eurasian Economic Union. In particular, the study of the experience of other regional associations presumes that the process of regional economic integration will have a positive impact on the dynamics of the attraction of foreign direct investment inflows in the region. In addition, regional integration will mitigate the problem of “limited” markets of the Member States of the Economic Union and, therefore, will help to increase the amount of investment resources in the manufacturing industry and services sector of the economy. The creation of the common energy markets in the framework of the new regional association would strengthen the resource-oriented domestic large-scale business and prepare the groundwork for the emergence of new transnational corporations, cooperating within the

  14. Wing Whiteness as an Indicator of Age, Immunocompetence, and Testis Size in the Eurasian Black-Billed Magpie (Pica pica)

    National Research Council Canada - National Science Library

    Guillermo Blanco; Juan A. Fargallo

    2013-01-01

    ... them. We investigated covariation of the white wing patch of the Eurasian Black-billed Magpie (Pica pica) with age, sex, feather wear, spleen size, parasite infection, and testis size to evaluate whether this trait is indicative of individual quality...

  15. Aquatic Plant Control Research Program. A Survey of the Continental United States for Pathogens of Eurasian Watermilfoil

    Science.gov (United States)

    1988-04-01

    proven. Hayslip and Zettler (1973) later reported a failure to intro- duce the Northeast River disease in Florida, and Bean , Fusco, and Klarman (1973...Hecht (1981) tested the pathogenicity of Fusarium sporotrichioides to Eurasian water- milfoil. The fungus that was isolated from Eurasian...spicatum L.," Canadian Journal of Plant Science, Vol 59, pp 201-215. Andrews, J. H., and Hecht, E. P. 1981. "Evidence for Pathogenicity of Fusarium

  16. A comparative analysis of the complete mitochondrial genome of the Eurasian otter Lutra lutra (Carnivora; Mustelidae).

    Science.gov (United States)

    Ki, Jang-Seu; Hwang, Dae-Sik; Park, Tae-Jin; Han, Sang-Hoon; Lee, Jae-Seong

    2010-04-01

    Otter populations are declining throughout the world and most otter species are considered endangered. Molecular methods are suitable tools for population genetic research on endangered species. In the present study, we analyzed the complete mitochondrial genome (mitogenome) sequence of the Eurasian otter Lutra lutra. The mitochondrial DNA sequence of the Eurasian otter is 16,505 bp in length and consists of 13 protein-coding genes, 22 tRNAs, 2 rRNAs, and a control region (CR). The CR sequence of otters from Europe and Asia showed nearly identical numbers and nucleotide sequences of minisatellites. Phylogenetic analysis of Mustelidae mitogenomes, including individual genes, revealed that Lutrinae and Mustelinae form a clade, and that L. lutra and Enhydra lutris are sister taxa within the Lutrinae. Phylogenetic analyses revealed that of the 13 mitochondrial protein-coding genes, ND5 is the most reliable marker for analysis of phylogenetic relationships within the Mustelidae.

  17. Suspected flunixin poisoning of a wild Eurasian Griffon Vulture from Spain.

    Science.gov (United States)

    Zorrilla, Irene; Martinez, Rosa; Taggart, Mark A; Richards, Ngaio

    2015-04-01

    Exposure to residues of the nonsteroidal anti-inflammatory drug (NSAID) diclofenac present in livestock carcasses has caused extensive declines in 3 Gyps vulture species across Asia. The carcass of a wild Eurasian Griffon Vulture (Gyps fulvus) was found in 2012 on an Andalucian (Spain) game hunting reserve and examined forensically. The bird had severe visceral gout, a finding consistent with Gyps vultures from Asia that have been poisoned by diclofenac. Liver and kidney samples from this Eurasian Griffon Vulture contained elevated flunixin (an NSAID) levels (median = 2.70 and 6.50 mg/kg, respectively). This is the first reported case of a wild vulture being exposed to and apparently killed by an NSAID outside Asia. It is also the first reported instance of mortality in the wild resulting from environmental exposure to an NSAID other than diclofenac. © 2014 Society for Conservation Biology.

  18. Ancestry and demography and descendants of Iron Age nomads of the Eurasian Steppe

    Science.gov (United States)

    Unterländer, Martina; Palstra, Friso; Lazaridis, Iosif; Pilipenko, Aleksandr; Hofmanová, Zuzana; Groß, Melanie; Sell, Christian; Blöcher, Jens; Kirsanow, Karola; Rohland, Nadin; Rieger, Benjamin; Kaiser, Elke; Schier, Wolfram; Pozdniakov, Dimitri; Khokhlov, Aleksandr; Georges, Myriam; Wilde, Sandra; Powell, Adam; Heyer, Evelyne; Currat, Mathias; Reich, David; Samashev, Zainolla; Parzinger, Hermann; Molodin, Vyacheslav I.; Burger, Joachim

    2017-03-01

    During the 1st millennium before the Common Era (BCE), nomadic tribes associated with the Iron Age Scythian culture spread over the Eurasian Steppe, covering a territory of more than 3,500 km in breadth. To understand the demographic processes behind the spread of the Scythian culture, we analysed genomic data from eight individuals and a mitochondrial dataset of 96 individuals originating in eastern and western parts of the Eurasian Steppe. Genomic inference reveals that Scythians in the east and the west of the steppe zone can best be described as a mixture of Yamnaya-related ancestry and an East Asian component. Demographic modelling suggests independent origins for eastern and western groups with ongoing gene-flow between them, plausibly explaining the striking uniformity of their material culture. We also find evidence that significant gene-flow from east to west Eurasia must have occurred early during the Iron Age.

  19. Eurasian golden jackal as host of canine vector-borne protists.

    Science.gov (United States)

    Mitková, Barbora; Hrazdilová, Kristýna; D'Amico, Gianluca; Duscher, Georg Gerhard; Suchentrunk, Franz; Forejtek, Pavel; Gherman, Călin Mircea; Matei, Ioana Adriana; Ionică, Angela Monica; Daskalaki, Aikaterini Alexandra; Mihalca, Andrei Daniel; Votýpka, Jan; Hulva, Pavel; Modrý, David

    2017-04-14

    Jackals are medium-sized canids from the wolf-like clade, exhibiting a unique combination of ancestral morphotypes, broad trophic niches, and close phylogenetic relationships with the wolf and dog. Thus, they represent a potential host of several pathogens with diverse transmission routes. Recently, populations of the Eurasian golden jackal Canis aureus have expanded into the Western Palaearctic, including most of Europe. The aim of our study was to examine Eurasian golden jackals from Romania, Czech Republic and Austria for a wide spectrum of vector-borne protists and to evaluate the role of this species as a reservoir of disease for domestic dogs and/or humans. Diagnostic polymerase chain reaction (PCR) DNA amplifications revealed 70% of jackals to be positive for Hepatozoon, 12.5% positive for piroplasms, and one individual positive for Leishmania infantum. Phylogenetic analyses of partial 18S rDNA sequences invariably placed sequenced isolates of Hepatozoon into the H. canis clade. For piroplasms, both the 18S and cox1 sequences obtained confirmed the presence of Babesia canis and "Theileria annae" in 5 and 2 individuals, respectively, providing the first records of these two piroplasmids in Eurasian golden jackals. A single animal from Dolj County (Romania) was PCR-positive for L. infantum, as confirmed also by sequencing of ITS1-5.8S. Apparently, expanding populations of jackals can play a significant role in spreading and maintaining new Babesia canis foci in Central Europe. The role of jackals in the epidemiology of "Theileria annae" and H. canis is probably similar to that of red foxes and should be taken into account in further research on these parasites. Also the presence of L. infantum deserves attention. Our study confirms that once established, the populations of Eurasian golden jackals constitute natural reservoirs for many canine vector-borne diseases, analogous to the role of the coyotes in North America.

  20. Patterns of variation in reproductive parameters in Eurasian lynx (Lynx lynx)

    OpenAIRE

    Nilsen, Erlend B; John D C Linnell; Odden, John; Samelius, Gustaf; Andrén, Henrik

    2011-01-01

    Detailed knowledge of the variation in demographic rates is central for our ability to understand the evolution of life history strategies and population dynamics, and to plan for the conservation of endangered species. We studied variation in reproductive output of 61 radio-collared Eurasian lynx females in four Scandinavian study sites spanning a total of 223 lynx-years. Specifically, we examined how the breeding proportion and litter size varied among study areas and age classes (2-year-ol...

  1. The Eurasian Economic Union: A Brittle Roadblock on China's "One Belt - One Road"

    DEFF Research Database (Denmark)

    Zank, Wolfgang

    2017-01-01

    to participate. However, Georgia, Moldova and Ukraine opted for an association agreement with the EU, a move to which Russia responded by the annexation of Crimea and starting an insurgency in Eastern Ukraine. In 2015, the EEU officially started with the participation of only five countries: Armenia, Belarus...... members. Keywords: China, European-Atlantic Security Community, Eurasian Economic Union, “One Belt One Road” Initiative, Russia’s “Monroe Doctrine”....

  2. Near-Slope changes in the Eurasian and Makarov Basins from Glider Surveys

    Science.gov (United States)

    2015-09-30

    1000-m G2 Slocum gliders . We have also ordered and received the high-frequency (1 MHz) Aquadopp ADCP from Nortek. RESULTS We have have initialized...for public release; distribution is unlimited. Near-Slope changes in the Eurasian and Makarov Basins from glider surveys Dr. Peter Winsor School of...73 LONG-TERM GOALS To conduct high-latitude glider surveys that will lead to i) enhanced autonomous observational capabilities in the high Arctic

  3. The Eurasian otter (Lutra lutra) as a potential host for rickettsial pathogens in southern Italy

    OpenAIRE

    Santoro, Mario; D?Alessio, Nicola; Cerrone, Anna; Lucibelli, Maria Gabriella; Borriello, Giorgia; Aloise,Gaetano; Auriemma, Clementina; Riccone, Nunzia; Galiero, Giorgio

    2017-01-01

    Canine monocytic ehrlichiosis and rickettsiosis are zoonotic tick-borne diseases of canids caused by the intracellular obligate bacteria Ehrlichia canis and Rickettsia species respectively. In this study, we investigated using standard and real-time PCR and sequencing, the occurrence and molecular characterization of E. canis and Rickettsia species in the Eurasian otter (Lutra lutra) from the southern Italian population. Samples were screened by using molecular assays also for Neospora caninu...

  4. Habitat correlates of the Eurasian otter Lutra lutra recolonizing Central Poland

    OpenAIRE

    Romanowski, Jerzy; Brzezi?ski, Marcin; ?mihorski, Micha?

    2012-01-01

    The increase in Eurasian otter Lutra lutra populations in their natural range and recolonization processes are recently observed in several European countries. We address the process of otter recolonization and habitat utilization in Central Poland over 14?years. Field surveys in 1998 and 2007 documented increase in occurrence of the species. The frequency of positive sites denoted 15?% in 1993, 38?% in 1998, and 89?% in 2007. Otter occurrence at study sites was positively affected by river w...

  5. The Near Threatened Eurasian otter Lutra lutra in Morocco : no sign of recovery

    OpenAIRE

    Delibes de Castro, Miguel; Calzada Samperio, Javier; Clavero Pineda, Miguel; Fernández, Néstor; Gutiérrez Expósito, Carlos; Revilla, Eloy; Román, Jacinto

    2012-01-01

    Although the Near Threatened Eurasian otter Lutra lutra has been recovering in Europe since the 1980s nothing is known about population trends of the species in northern Africa. Ninety sites was searched for signs of otters in northern and western Morocco in 1983 and we repeated this survey in 2011. At each site we searched for otter spraints (faeces) or clear footprints along a maximum of 600m of river bank, ending the search when the first sign was found. Overall res...

  6. The Eurasian Integration in the Context of Civilizational Self-Determination of Russia

    Directory of Open Access Journals (Sweden)

    Baranov Nikolay Alekseevich

    2015-12-01

    Full Text Available Russia is currently in search of its place and its role in the world. In the conditions of intense relations with the Western states, a political discourse is experiencing the change of priorities in defining a direction of the country’s development. Therefore the European vector which served as an orientation point in the political elite in 1990s - the beginning of 2000s, is replaced by the Eurasian one. It is also caused by strengthening the economic and political influence of the Asian states on the international processes. The Eurasian integration project initiated by Russia, finds support among a number of the countries of the post-Soviet territory. The created Eurasian economic union becomes the significant subject of the international political process that gives confidence to Russia as far as its forces in building relations with the Western countries are concerned, as well as the search of self-identity. Russia aspires to become the bridge connecting the West and the East that can serve as its contribution to the creation of equal relations in the global world. The article attempts to highlight the trends of modern Russian civilization identification process within the political science discourse. This process is associated with inconsistent implementation of the political, legal, socio-economic and socio-cultural (ideological projects of society and the state modernization. The author focuses on the fact that the center of the discussions in the socio-political discourse is increasingly shifting towards the search of Russian interests not within civilizational projects, but in the search for an independent path of development, which is most fully consistent with the historical destiny of Russia. The author substantiates positive and negative factors that contribute to the realization of the Eurasian project aimed at the integration of countries and peoples in the context of the implementation of democratic reforms and the national

  7. Reconstructions of human history by mapping dental markers in living Eurasian populations

    Science.gov (United States)

    Kashibadze, Vera F.; Nasonova, Olga G.; Nasonov, Dmitry S.

    2013-01-01

    Using advances in gene geography and anthropophenetics, the phenogeographical method for anthropological research was initiated and developed using dental data. Statistical and cartographical analyses are provided for 498 living Eurasian populations. Mapping principal components supplied evidence for the phene pool structure in Eurasian populations, and for reconstructions of Homo sapiens history on the continent. Longitudinal variability seems to be the most important regularity revealed by principal components analysis (PCA) and mapping, indicating the division of the whole area into western and eastern main provinces. So, the most ancient scenario in the history of Eurasian populations developed from two perspective different groups: a western group related to ancient populations of West Asia and an eastern one rooted in ancestry in South and/or East Asia. In spite of the enormous territory and the revealed divergence, the populations of the continent have undergone wide scale and intensive timeespace interaction. Many details in the revealed landscapes are background to different historical events. Migrations and assimilation are two essential phenomena in Eurasian history: the widespread of the western combination through the whole continent to the Pacific coastline and the movement of the paradoxical combinations of eastern and western markers from South or Central Asia to the east and west. Taking into account that no additional eastern combinations in the total variation in Asian groups have been found, but that mixed or western markers' sets and that eastern dental characteristics are traced in Asia since Homo erectus, the assumption is made in favour of the hetero-level assimilation in the eastern province and of net-like evolution of H. sapiens.

  8. THE REGISTRY OF SYSTEMIC LUPUS ERYTHEMATOSUS PATIENTS, A EURASIAN COHORT (RENAISSANCE)

    OpenAIRE

    E. A. Aseeva; A. I. Dubikov; L. A. Levasheva; G. M. Koilubaeva; M. K. Dzhetybaeva; V. T. Eralieva; E. R. Karimova; B. G. Isaeva; M. B. Kalykova; M. M. Saparbaeva; S. M. Isaeva; Zh. I. Omarbekova; E. S. Solovyeva; T M Reshetnyak; N G Klyukvina

    2016-01-01

    The article presents the data of international registries and cohort studies of systemic lupus erythematosus (SLE). It justifies the purpose and objectives of the international registry of SLE patients, a Eurasian cohort (RENAISSANCE), which was launched in 2012 and amalgamated the leading rheumatology centers of the Russian Federation (V.A. Nasonova Research Institute of Rheumatology; Department of Rheumatology,  Pacific State Medical University), Kazakhstan (Department of Rheumatology,  S.D...

  9. Impacts of early autumn Arctic sea ice concentration on subsequent spring Eurasian surface air temperature variations

    Science.gov (United States)

    Chen, Shangfeng; Wu, Renguang

    2017-11-01

    This study reveals a close relation between autumn Arctic sea ice change (SIC) in the Laptev Sea-eastern Siberian Sea-Beaufort Sea and subsequent spring Eurasian surface air temperature (SAT) variation. Specifically, more (less) SIC over the above regions in early autumn generally correspond to SAT warming (cooling) over the mid-high latitudes of Eurasia during subsequent spring. Early autumn Arctic SIC affects spring Eurasian SAT via modulating spring Arctic Oscillation (AO) associated atmospheric changes. The meridional temperature gradient over the mid-high latitudes decreases following the Arctic sea ice loss. This results in deceleration of prevailing westerly winds over the mid-latitudes of the troposphere, which leads to increase in the upward propagation of planetary waves and associated Eliassen-Palm flux convergence in the stratosphere over the mid-high latitudes. Thereby, westerly winds in the stratosphere are reduced and the polar vortex is weakened. Through the wave-mean flow interaction and downward propagation of zonal wind anomalies, a negative spring AO pattern is formed in the troposphere, which favors SAT cooling over Eurasia. The observed autumn Arctic SIC-spring Eurasian SAT connection is reproduced in the historical simulation (1850-2005) of the flexible global ocean-atmosphere-land system model, spectral version 2 (FGOALS-s2). The FGOALS-s2 also simulates the close connection between autumn SIC and subsequent spring AO. Further analysis suggests that the prediction skill of the spring Eurasian SAT was enhanced when taking the autumn Arctic SIC signal into account.

  10. Eurasian Economic Union: Opportunities and Barriers to Regional and Global Leadership

    Directory of Open Access Journals (Sweden)

    In Andronova

    2016-09-01

    Full Text Available The Eurasian Economic Union (EEU is a new integration grouping in the post-Soviet space that is generating heightened interest as a global economy with the potential to become a new regional and global actor. This article analyzes the effectiveness of the Eurasian integration processes and proposes several actions to strengthen economic relations among EEU members through detecting and building common economic interests. Russia accounts for as much as 87% of the EEU’s geo-economic potential, which stresses the country’s role as anintegrative hub. The EEU benefits are thus unevenly distributed among its participants. Moreover, these benefits lack consistency and long-term orientation, which may threaten the EEU’s existence if markets and international economic relations change.This article analyses the interrelation and interdependency of national economies in terms of the mutual trade in goods and services and investment cooperation. It finds that the level of economic integration does not meet the interests of strengthening Eurasian integration. Despite the huge benefits of the Customs Union, trade volumes have not increased and the structure of manufacturing and cooperation ties remain unchanged. This article recommends that developing and implementing a common industrial and agricultural policy would strengthen the EEU, and proposes an approach to estimate the results of such a policy.

  11. Musculoskeletal anatomy of the Eurasian lynx, Lynx lynx (Carnivora: Felidae) forelimb: Adaptations to capture large prey?

    Science.gov (United States)

    Viranta, Suvi; Lommi, Hanna; Holmala, Katja; Laakkonen, Juha

    2016-06-01

    Mammalian carnivores adhere to two different feeding strategies relative to their body masses. Large carnivores prey on animals that are the same size or larger than themselves, whereas small carnivores prey on smaller vertebrates and invertebrates. The Eurasian lynx (Lynx lynx) falls in between these two categories. Lynx descend from larger forms that were probably large prey specialists, but during the Pleistocene became predators of small prey. The modern Eurasian lynx may be an evolutionary reversal toward specializing in large prey again. We hypothesized that the musculoskeletal anatomy of lynx should show traits for catching large prey. To test our hypothesis, we dissected the forelimb muscles of six Eurasian lynx individuals and compared our findings to results published for other felids. We measured the bones and compared their dimensions to the published material. Our material displayed a well-developed pectoral girdle musculature with some uniquely extensive muscle attachments. The upper arm musculature resembled that of the pantherine felids and probably the extinct sabertooths, and also the muscles responsible for supination and pronation were similar to those in large cats. The muscles controlling the pollex were well-developed. However, skeletal indices were similar to those of small prey predators. Our findings show that lynx possess the topographic pattern of muscle origin and insertion like in large felids. J. Morphol. 277:753-765, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  12. Large-Scale Genetic Structuring of a Widely Distributed Carnivore - The Eurasian Lynx (Lynx lynx)

    Science.gov (United States)

    Rueness, Eli K.; Naidenko, Sergei; Trosvik, Pål; Stenseth, Nils Chr.

    2014-01-01

    Over the last decades the phylogeography and genetic structure of a multitude of species inhabiting Europe and North America have been described. The flora and fauna of the vast landmasses of north-eastern Eurasia are still largely unexplored in this respect. The Eurasian lynx is a large felid that is relatively abundant over much of the Russian sub-continent and the adjoining countries. Analyzing 148 museum specimens collected throughout its range over the last 150 years we have described the large-scale genetic structuring in this highly mobile species. We have investigated the spatial genetic patterns using mitochondrial DNA sequences (D-loop and cytochrome b) and 11 microsatellite loci, and describe three phylogenetic clades and a clear structuring along an east-west gradient. The most likely scenario is that the contemporary Eurasian lynx populations originated in central Asia and that parts of Europe were inhabited by lynx during the Pleistocene. After the Last Glacial Maximum (LGM) range expansions lead to colonization of north-western Siberia and Scandinavia from the Caucasus and north-eastern Siberia from a refugium further east. No evidence of a Berinigan refugium could be detected in our data. We observed restricted gene flow and suggest that future studies of the Eurasian lynx explore to what extent the contemporary population structure may be explained by ecological variables. PMID:24695745

  13. Repetitive sequences in Eurasian lynx (Lynx lynx L.) mitochondrial DNA control region.

    Science.gov (United States)

    Sindičić, Magda; Gomerčić, Tomislav; Galov, Ana; Polanc, Primož; Huber, Duro; Slavica, Alen

    2012-06-01

    Mitochondrial DNA (mtDNA) control region (CR) of numerous species is known to include up to five different repetitive sequences (RS1-RS5) that are found at various locations, involving motifs of different length and extensive length heteroplasmy. Two repetitive sequences (RS2 and RS3) on opposite sides of mtDNA central conserved region have been described in domestic cat (Felis catus) and some other felid species. However, the presence of repetitive sequence RS3 has not been detected in Eurasian lynx (Lynx lynx) yet. We analyzed mtDNA CR of 35 Eurasian lynx (L. lynx L.) samples to characterize repetitive sequences and to compare them with those found in other felid species. We confirmed the presence of 80 base pairs (bp) repetitive sequence (RS2) at the 5' end of the Eurasian lynx mtDNA CR L strand and for the first time we described RS3 repetitive sequence at its 3' end, consisting of an array of tandem repeats five to ten bp long. We found that felid species share similar RS3 repetitive pattern and fundamental repeat motif TACAC.

  14. Early Eurasian migration traces in the Tarim Basin revealed by mtDNA polymorphisms.

    Science.gov (United States)

    Cui, Yinqiu; Li, Chunxiang; Gao, Shizhu; Xie, Chengzhi; Zhou, Hui

    2010-08-01

    The mitochondrial DNA (mtDNA) polymorphisms of 58 samples from the Daheyan village located in the central Taklamakan Desert of the Tarim Basin were determined in this study. Among the 58 samples, 29 haplotypes belonging to 18 different haplogroups were analyzed. Almost all the mtDNAs belong to a subset of either the defined Western or Eastern Eurasian pool. Extensive Eastern Eurasian lineages exist in the Daheyan population in which Northern-prevalent haplogroups present higher frequencies. In the limited existing Western Eurasian lineages, two sub-haplogroups, U3 and X2, that are rare in Central Asia were found in this study, which may be indicative of the remnants of an early immigrant population from the Near East and Caucasus regions preserved only in the Tarim Basin. The presence of U3 in modern and archeological samples in the Tarim Basin suggests that the immigration took place earlier than 2,000 years ago and points to human continuity in this area, with at least one Western lineage originating from the Near East and Caucasus regions. Copyright 2010 Wiley-Liss, Inc.

  15. Large-scale genetic structuring of a widely distributed carnivore--the Eurasian lynx (Lynx lynx).

    Science.gov (United States)

    Rueness, Eli K; Naidenko, Sergei; Trosvik, Pål; Stenseth, Nils Chr

    2014-01-01

    Over the last decades the phylogeography and genetic structure of a multitude of species inhabiting Europe and North America have been described. The flora and fauna of the vast landmasses of north-eastern Eurasia are still largely unexplored in this respect. The Eurasian lynx is a large felid that is relatively abundant over much of the Russian sub-continent and the adjoining countries. Analyzing 148 museum specimens collected throughout its range over the last 150 years we have described the large-scale genetic structuring in this highly mobile species. We have investigated the spatial genetic patterns using mitochondrial DNA sequences (D-loop and cytochrome b) and 11 microsatellite loci, and describe three phylogenetic clades and a clear structuring along an east-west gradient. The most likely scenario is that the contemporary Eurasian lynx populations originated in central Asia and that parts of Europe were inhabited by lynx during the Pleistocene. After the Last Glacial Maximum (LGM) range expansions lead to colonization of north-western Siberia and Scandinavia from the Caucasus and north-eastern Siberia from a refugium further east. No evidence of a Berinigan refugium could be detected in our data. We observed restricted gene flow and suggest that future studies of the Eurasian lynx explore to what extent the contemporary population structure may be explained by ecological variables.

  16. Large-scale genetic structuring of a widely distributed carnivore--the Eurasian lynx (Lynx lynx.

    Directory of Open Access Journals (Sweden)

    Eli K Rueness

    Full Text Available Over the last decades the phylogeography and genetic structure of a multitude of species inhabiting Europe and North America have been described. The flora and fauna of the vast landmasses of north-eastern Eurasia are still largely unexplored in this respect. The Eurasian lynx is a large felid that is relatively abundant over much of the Russian sub-continent and the adjoining countries. Analyzing 148 museum specimens collected throughout its range over the last 150 years we have described the large-scale genetic structuring in this highly mobile species. We have investigated the spatial genetic patterns using mitochondrial DNA sequences (D-loop and cytochrome b and 11 microsatellite loci, and describe three phylogenetic clades and a clear structuring along an east-west gradient. The most likely scenario is that the contemporary Eurasian lynx populations originated in central Asia and that parts of Europe were inhabited by lynx during the Pleistocene. After the Last Glacial Maximum (LGM range expansions lead to colonization of north-western Siberia and Scandinavia from the Caucasus and north-eastern Siberia from a refugium further east. No evidence of a Berinigan refugium could be detected in our data. We observed restricted gene flow and suggest that future studies of the Eurasian lynx explore to what extent the contemporary population structure may be explained by ecological variables.

  17. Persistent shift of the Arctic polar vortex towards the Eurasian continent in recent decades

    Science.gov (United States)

    Zhang, Jiankai; Tian, Wenshou; Chipperfield, Martyn P.; Xie, Fei; Huang, Jinlong

    2016-12-01

    The wintertime Arctic stratospheric polar vortex has weakened over the past three decades, and consequently cold surface air from high latitudes is now more likely to move into the middle latitudes. However, it is not known if the location of the polar vortex has also experienced a persistent change in response to Arctic climate change and whether any changes in the vortex position have implications for the climate system. Here, through the analysis of various data sets and model simulations, we show that the Arctic polar vortex shifted persistently towards the Eurasian continent and away from North America in February over the past three decades. This shift is found to be closely related to the enhanced zonal wavenumber-1 waves in response to Arctic sea-ice loss, particularly over the Barents-Kara seas (BKS). Increased snow cover over the Eurasian continent may also have contributed to the shift. Our analysis reveals that the vortex shift induces cooling over some parts of the Eurasian continent and North America which partly offsets the tropospheric climate warming there in the past three decades. The potential vortex shift in response to persistent sea-ice loss in the future, and its associated climatic impact, deserve attention to better constrain future climate changes.

  18. Integration Dilemma within the Eurasian Space in the Context of the Ukrainian Crisis

    Directory of Open Access Journals (Sweden)

    Antonina A. Durdyeva

    2015-01-01

    Full Text Available The article analyses the reaction of top officials, politicians and representatives of the expert community of the Eurasian Economic Union member countries on the aggravation of "Ukrainian crisis" in the context of plans and directions for further Eurasian integration. Today, in the scientific community is becoming a popular" dilemma of integration " as a systematic pattern that determines the development of relations between the integration associations. The dilemma of integration is a political phenomenon, a regular and predictable. Ukrainian crisis, which has become a litmus test of conflict of representations of the CIS countries on the extent and depth of their involvement in the processes of regional integration , most clearly outlined the presence of such dilemma within the CIS. In the current situation for Belarus and Kazakhstan as two , along with Russia , the main designers of the Eurasian field, the dilemma of integration takes a fundamentally different meaning and becomes a so-called "Dilemma of integrations", or contradiction between the desire of these countries to secure the most favorable conditions in its relations with Moscow and reluctance to fully bear the burden of the costs and constraints arising in relations with the EU due to the commitments of the EAEC. Based on the material of the official position of the representatives of Republic of Kazakhstan and the Republic of Belarus the author of the article explores the implications of the Ukrainian crisis in relations of Three: Moscow, Astana and Minsk.

  19. Sempre più veloci perché i fisici accelerano le particelle : la vera storia del bosone di Higgs

    CERN Document Server

    Amaldi, Ugo

    2012-01-01

    Nell’estate 2012 l’annuncio della scoperta del «bosone di Higgs» ha fatto conoscere a tutti il CERN di Ginevra e il suo grande anello sotterraneo LHC, la macchina più gigantesca mai costruita dall’umanità. Ma perché i fisici costruiscono acceleratori di particelle sempre più potenti? Che cosa vogliono scoprire? E quegli acceleratori servono soltanto a produrre conoscenza, o hanno anche qualche applicazione nella vita quotidiana? Un protagonista della ricerca scientifica ripercorre un secolo di progressi, dalla storia curiosa della prima radiografia fino alla speciale particella che oggi spiega perché la materia pesa, e la luce invece no. Un’avventura affascinante che ha anche straordinarie ricadute: da un lato permette di esplorare i primi istanti di vita dell’universo, dall’altro produce apparecchi capaci di diagnosticare le malattie e perfino di curare il cancro.

  20. Perched groundwater-surface interactions and their consequences in stream flow generation in a semi-arid headwater catchment

    Science.gov (United States)

    Molenat, Jerome; Bouteffeha, Maroua; Raclot, Damien; Bouhlila, Rachida

    2013-04-01

    In semi-arid headwater catchment, it is usually admitted that stream flow comes predominantly from Hortonian overland flow (infiltration excess overland flow). Consequently, subsurface flow processes, and especially perched or shallow groundwater flow, have not been studied extensively. Here we made the assumption that perched groundwater flow could play a significant role in stream flow generation in semi-arid catchment. To test this assumption, we analyzed stream flow time series of a headwater catchment in the Tunisian Cap Bon region and quantified the flow fraction coming from groundwater discharge and that from overland flow. Furthermore, the dynamics of the perched groundwater was analyzed, by focusing on the different perched groundwater-surface interaction processes : diffuse and local infiltration, diffuse exfiltration, and direct groundwater discharge to the stream channel. This work is based on the 2.6 km² Kamech catchment (Tunisia), which belongs to the long term Mediterranean hydrological observatory OMERE (Voltz and Albergel, 2002). Results show that even though Hortonian overland flow was the main hydrological process governing the stream flow generation, groundwater discharge contribution to the stream channel annually accounted for from 10% to 20 % depending on the year. Furthermore, at some periods, rising of groundwater table to the soil surface in bottom land areas provided evidences of the occurrence of saturation excess overland flow processes during some storm events. Reference Voltz , M. and Albergel , J., 2002. OMERE : Observatoire Méditerranéen de l'Environnement Rural et de l'Eau - Impact des actions anthropiques sur les transferts de masse dans les hydrosystèmes méditerranéens ruraux. Proposition d'Observatoire de Recherche en Environnement, Ministère de la Recherche.

  1. Application of HEC-RAS for flood forecasting in perched river-A case study of hilly region, China

    Science.gov (United States)

    Sun, Pingping; Wang, Shuqian; Gan, Hong; Liu, Bin; Jia, Ling

    2017-04-01

    Flooding in small and medium rivers are seriously threatening the safety of human beings’ life and property. The simulation forecasting of the river flood and bank risk in hilly region has gradually become a hotspot. At present, there are few studies on the simulation of hilly perched river, especially in the case of lacking section flow data. And the method of how to determine the position of the levee breach along the river bank is not much enough. Based on the characteristics of the sections in hilly perched river, an attempt is applied in this paper which establishes the correlation between the flow profile computed by HEC-RAS model and the river bank. A hilly perched river in Lingshi County, Shanxi Province of China, is taken as the study object, the levee breach positions along the bank are simulated under four different design storm. The results show that the flood control standard of upper reach is high, which can withstand the design storm of 100 years. The current standard of lower reach is low, which is the flooding channel with high frequency. As the standard of current channel between the 2rd and the 11th section is low, levee along that channel of the river bank is considered to be heighten and reinforced. The study results can provide some technical support for flood proofing in hilly region and some reference for the reinforcement of river bank.

  2. Molecular identification of a yellow perch viral disease associated with exposure to oil sands process affected waters

    Energy Technology Data Exchange (ETDEWEB)

    Hogan, N.; Van den Heuvel, M.; Phalen, L. [Prince Edward Island Univ., Charlottetown, PE (Canada)

    2010-07-01

    Large volumes of tailings and process affected water are generated as a result of oil sand mining processes. This presentation discussed the safe incorporation of these wastes into the terrestrial and aquatic landscape. A study was conducted in which yellow perch were stocked into experimental ponds, namely Demonstration Pond and South Bison Pond, during the periods of 1995-1997 and 2008-2010. Demonstration Pond was comprised of mature fine tailings capped with natural surface water, while South Bison Pond was formed at a site surrounded by overburden or lean oil sands. Disease surveys were conducted at these experimental ponds and also at Mildred, Sucker, and Kimowin Lakes. External white nodular lesions, characteristic of lymphocystis disease were observed on perch at all sites except Kimowin Lake. The identity of the virus was confirmed by DNA extraction and PCR with genotype generic major capsid protein gene primers. The presence of lymphocystis disease virus in perch was confirmed through sequencing of PCR results. The viral genotype appeared to be different from any previously isolated viral genotype. During the course of the study, there was an increasing incidence of the disease at Demonstration Pond and a decreasing incidence at the South Bison Pond. The intensity of the disease was found to be proportional to the incidence, which was positively correlated with changes in naphthenic acid concentration.

  3. Fossil climbing perch and associated plant megafossils indicate a warm and wet central Tibet during the late Oligocene.

    Science.gov (United States)

    Wu, Feixiang; Miao, Desui; Chang, Mee-Mann; Shi, Gongle; Wang, Ning

    2017-04-13

    Understanding the Tibetan Plateau's palaeogeography and palaeoenvironment is critical for reconstructing Asia's climatic history; however, aspects of the plateau's uplift history remain unclear. Here, we report a fossil biota that sheds new light on these issues. It comprises a fossil climbing perch (Anabantidae) and a diverse subtropical fossil flora from the Chattian (late Oligocene) of central Tibet. The fish, Eoanabas thibetana gen. et sp. nov., is inferred to be closely related to extant climbing perches from tropical lowlands in south Asia and sub-Saharan Africa. It has osteological correlates of a labyrinth organ, which in extant climbing perches gives them the ability to breathe air to survive warm, oxygen-poor stagnant waters or overland excursion under moist condition. This indicates that Eoanabas likewise lived in a warm and humid environment as suggested by the co-existing plant assemblage including palms and golden rain trees among others. As a palaeoaltimeter, this fossil biota suggests an elevation of ca. 1,000 m. These inferences conflict with conclusions of a high and dry Tibet claimed by some recent and influential palaeoaltimetry studies. Our discovery prompts critical re-evaluation of prevailing uplift models of the plateau and their temporal relationships with the Cenozoic climatic changes.

  4. Data Management and Data Quality in PERCH, a Large International Case-Control Study of Severe Childhood Pneumonia.

    Science.gov (United States)

    Watson, Nora L; Prosperi, Christine; Driscoll, Amanda J; Higdon, Melissa M; Park, Daniel E; Sanza, Megan; DeLuca, Andrea N; Awori, Juliet O; Goswami, Doli; Hammond, Emily; Hossain, Lokman; Johnson, Catherine; Kamau, Alice; Kuwanda, Locadiah; Moore, David P; Neyzari, Omid; Onwuchekwa, Uma; Parker, David; Sapchookul, Patranuch; Seidenberg, Phil; Shamsul, Arifin; Siazeele, Kazungu; Srisaengchai, Prasong; Sylla, Mamadou; Levine, Orin S; Murdoch, David R; O'Brien, Katherine L; Wolff, Mark; Deloria Knoll, Maria

    2017-06-15

    The Pneumonia Etiology Research for Child Health (PERCH) study is the largest multicountry etiology study of pediatric pneumonia undertaken in the past 3 decades. The study enrolled 4232 hospitalized cases and 5325 controls over 2 years across 9 research sites in 7 countries in Africa and Asia. The volume and complexity of data collection in PERCH presented considerable logistical and technical challenges. The project chose an internet-based data entry system to allow real-time access to the data, enabling the project to monitor and clean incoming data and perform preliminary analyses throughout the study. To ensure high-quality data, the project developed comprehensive quality indicator, data query, and monitoring reports. Among the approximately 9000 cases and controls, analyzable laboratory results were available for ≥96% of core specimens collected. Selected approaches to data management in PERCH may be extended to the planning and organization of international studies of similar scope and complexity. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

  5. Selective Control of Eurasian Watermilfoil and Curlyleaf Pondweed in Noxon Rapids Reservoir, Montana: Herbicide Small-Plot Evaluations, 2010-2011

    Science.gov (United States)

    2014-03-01

    sibiricum Komarov Northern watermilfoil Myriophyllum spicatum L. Eurasian watermilfoil Najas flexilis L. (Willd.) Rost & Schmidt Slender naiad...54 21† 7* Myriophyllum spicatum L. Eurasian watermilfoil 42 20† 13* Najas flexilis L. (Willd.) Rost & Schmidt Slender naiad 0 0 1 Nitella sp...stargrass 11 40† 31* Myriophyllum sibiricum Komarov Northern watermilfoil 41 42 14* Myriophyllum spicatum L. Eurasian watermilfoil 70 30† 24* Najas

  6. Some aspects in early life stage of climbing perch, Anabas testudineus larvae

    Directory of Open Access Journals (Sweden)

    Ponpanom Promkaew

    2005-02-01

    Full Text Available The sexual maturity of female climbing perch, Anabas testudineus was studied by determining fecundity and gonadosomatic index (GSI. It was found that the size at sexual maturity of female climbing perch was 15.20±1.24 cm (mean±SD in total length and 61.10±17.32 g in body weight. The eggs were floating and rounded. The fertilized eggs had a diameter of 830±39 μm. The fecundity was 24,120.5±3,328.24 ova/ fish and gonadosomatic index (GSI was 10.4±2.5%. Newly hatched larvae of climbing perch were produced by induced spawning using chemical injection (Suprefact and Motilium. The sexually mature fishes were cultured in fiber-glass tank (water volume 300 liters with the ratio of male and female brooders 2:1. The fertilization rate, hatching out and hatching rate experiments were carried out using a 15-liter glass aquarium (water volume 10 liters containing 7,000-9,000 eggs. It was found that the eggs were floating and rounded. The fertilized eggs had a diameter of 830±39 μm. The average fertilization rate was 92.67%, hatching out was 20 hr 30 min and average hatching rate was 87.44% at a water temperature of 27.0-30.5ºC. Sampling of the newly-hatched larvae was done at 2-hour intervals, when 20 of them were randomly taken and preserved in 10% buffered formalin for later deter-mination of yolk absorption time. Observation using a microscope revealed that newly hatched larvae were 2.02±0.20 mm in total length and had yolk sacs of 111.33±46.19 mm3 in volume. The yolk sacs were completely absorbed within 92 hr after hatching at a water temperature of 27.0-30.5ºC. Up until full mouth development (start of feeding, 2-hourly samplings of twenty newly hatched larvae were taken from an aquarium for observation of the size of mouth opening. All the larvae had open mouths about 28 hr after hatching (2.95±0.59 mm TL, with the mouths measuring 328.42±32.23 mm in height. The feeding experiments were carried out using a 15-liter glass aquarium (water

  7. An artificial perch to help Snail Kites handle an exotic Apple Snail

    Science.gov (United States)

    Pias, Kyle E.; Welch, Zach C.; Kitchens, Wiley M.

    2012-01-01

    In the United States, the Snail Kite (Rostrhamus sociabilis plumbeus) is a federally endangered species and restricted to the wetlands of south-central Florida where the current population numbers less than 1,500. The Snail Kite is an extreme dietary specialist, previously feeding almost exclusively on one species of snail, the Florida Apple Snail (Pomacea paludosa). Within the past decade, an exotic species of apple snail, the Island Apple Snail (Pomacea insularum), has become established on lakes in central Florida. Island Apple Snails are larger than the native Florida Apple Snails, and Snail Kites handle the exotic snails less efficiently. Juvenile Snail Kites, in particular, have lower daily energy balances while feeding on Island Apple Snails. An inexpensive, easy-to-construct platform was developed that would provide Snail Kites with a flat, stable surface on which to extract snails. The platform has the potential to reduce the difficulties Snail Kites experience when handling exotic snails, and may benefit the Snail Kite population as a whole. Initial observations indicate that Snail Kites use the platforms frequently, and snails extracted at the platforms are larger than snails extracted at other perches.

  8. Effects of freezing on white perch Morone americana (Gmelin, 1789): Implications for multivariate morphometrics

    Science.gov (United States)

    Kocovsky, Patrick

    2016-01-01

    This study tested the hypothesis that duration of freezing differentially affects whole-body morphometrics of a derived teleost. Whole-body morphometrics are frequently analyzed to test hypotheses of different species, or stocks within a species, of fishes. Specimens used for morphometric analyses are typically fixed or preserved prior to analysis, yet little research has been done on how fixation or preservation methods or duration of preservation of specimens might affect outcomes of multivariate statistical analyses of differences in shape. To determine whether whole-body morphometrics changed as a result of freezing, 23 whole-body morphometrics of age-1 white perch (Morone americana) from western Lake Erie (n = 211) were analyzed immediately after capture, after being held on ice overnight, and after freezing for 100 or 200 days. Discriminant function analysis revealed that all four groups differed significantly from one another (P < 0.0001). The first canonical axis reflected long-axis morphometrics, where there was a clear pattern of positive translation along this axis with duration of preservation. Re-classification analysis demonstrated fish were typically assigned to their original preservation class except for fish frozen 100 days, which assigned mostly to frozen 200 days. Morphometric comparisons using frozen fish must be done on fish frozen for identical periods of time to avoid biases related to the length of time they were frozen. Similar experiments should be conducted on other species and also using formalin- and alcohol-preserved specimens.

  9. A Red-Tailed Hawk perches on a stump at KSC.

    Science.gov (United States)

    2000-01-01

    This red-tailed hawk on the roadside at Kennedy Space Center appears to be eyeing the photographer. The red-tailed hawk has a stocky build and broad, rounded wings. Its wide range covers Alaska and Nova Scotia south to Panama. It can frequently be seen perched in a tree at the edge of a meadow, watching for movement in the grass below. It feeds mainly on small rodents. The Refuge encompasses 92,000 acres that are a habitat for more than 331 species of birds, 31 mammals, 117 fishes, and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds, as well as a variety of insects. Kennedy Space Center shares a boundary with the Merritt Island National Wildlife Refuge, encompassing 92,000 acres that are a habitat for more than 331 species of birds, 31 mammals, 117 fishes, and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds, as well as a variety of insects.

  10. Russia and China in the age of grand Eurasian projects: Prospects for integration between the Silk Road Economic Belt and the Eurasian Economic Union

    Directory of Open Access Journals (Sweden)

    Kaneshko Sangar

    2017-05-01

    Full Text Available Following the recent deterioration of relations between Russia and the West over crises in the Middle East and Ukraine, the relationship between Moscow and Beijing is growing stronger. In 2014, the two nations signed an unprecedented gas deal worth US$400 billion. In May 2015, Vladimir Putin and Xi Jinping agreed to coordinate the Moscow-led EEU with China’s Silk Road Economic Belt (SREB. Following these developments, authors and journalists heralded a new era in Sino-Russian relations in which the two nations would consolidate their forces to counter a US-led unipolar world. However, the nature of the relationship between China and Russia, the prospects for closer cooperation between the two nations, and the feasibility of integrating the two grand Eurasian projects are topics of fierce debate. This article maintains that while a consensus between Moscow and Beijing with regard to post-Cold War US unilateralism and their convergent interests have pushed China and Russia to cooperate on a range of global and regional issues, relations between the two Eurasian neighbours are complex and multi-faceted and are far from forming an anti-US bloc. Furthermore, the abstract nature of China’s Silk Road initiative and a number of significant obstacles make the feasibility of integration between the two projects a complicated task. Issues explored by this article include the development of mechanisms and agreement on a format for cooperation between the nations involved; the solution of practical issues such as rail gauges and corruption in the region; the prospects for an “equal partnership” in Sino-Russian relations and Moscow’s predicament with regards to its position as “junior partner” in Eurasia; and last but not least, the ever-growing threat of Islamic fundamentalism and regional security.

  11. PAN EURASIAN EXPERIMENT (PEEX - A RESEARCH INITIATIVE MEETING THE GRAND CHALLENGES OF THE CHANGING ENVIRONMENT OF THE NORTHERN PAN-EURASIAN ARCTIC-BOREAL AREAS

    Directory of Open Access Journals (Sweden)

    Hanna K. Lappalainen

    2014-01-01

    Full Text Available The Pan-Eurasian Experiment (PEEX is a new multidisciplinary, global change research initiative focusing on understanding biosphere-ocean-cryosphere-climate interactions and feedbacks in Arctic and boreal regions in the Northern Eurasian geographical domain. PEEX operates in an integrative way and it aims at solving the major scientific and society relevant questions in many scales using tools from natural and social sciences and economics. The research agenda identifies the most urgent large scale research questions and topics of the land-atmosphere-aquatic-anthropogenic systems and interactions and feedbacks between the systems for the next decades. Furthermore PEEX actively develops and designs a coordinated and coherent ground station network from Europe via Siberia to China and the coastal line of the Arctic Ocean together with a PEEX-modeling platform. PEEX launches a program for educating the next generation of multidisciplinary researcher and technical experts. This expedites the utilization of the new scientific knowledge for producing a more reliable climate change scenarios in regional and global scales, and enables mitigation and adaptation planning of the Northern societies. PEEX gathers together leading European, Russian and Chinese research groups. With a bottom-up approach, over 40 institutes and universities have contributed the PEEX Science Plan from 18 countries. In 2014 the PEEX community prepared Science Plan and initiated conceptual design of the PEEX land-atmosphere observation network and modeling platform. Here we present the PEEX approach as a whole with the specific attention to research agenda and preliminary design of the PEEX research infrastructure.

  12. Brain acetylcholinesterase activity in shiner perch (Cymatogaster aggregata) and juvenile chinook salmon (Oncorhynchus tshawytscha) after application of carbaryl to control burrowing shrimp within Willapa Bay, Washington.

    Science.gov (United States)

    Troiano, Alexandra T; King, Kerensa A; Grue, Christian E; Grassley, James M; Ekblad, Cathy J

    2013-11-01

    Carbaryl has been applied in Willapa Bay, Washington, for five decades to control burrowing shrimp (Neotrypaea californiensis and Upogebia pugettensis) on commercial oyster (Crassostrea gigas) beds. Concerns about effects on nontarget species, including fishes, have led to restrictions in use despite a lack of data on in situ exposure. We measured brain acetylcholinesterase (AChE) activity in adult Shiner perch (Cymatogaster aggregata) and juvenile Chinook salmon (Oncorhynchus tshawytscha) after operational applications. We hypothesized that exposure in Shiner perch would be greater than in juvenile Chinook salmon because of their greater site fidelity and benthic foraging. However, Shiner perch exhibited no statistically significant AChE inhibition. Enzyme activity was statistically decreased (≤14 %) in juvenile Chinook salmon after a second spray event; however, inhibition was less than that associated with overt effects and was similar to controls by 48 h after the spray. Diet analyses confirmed that Shiner perch were primarily feeding on benthic invertebrates and that juvenile Chinook salmon were feeding primarily within the water column. Composition of Shiner perch diets and amount of food consumed varied little among channels and time periods; however, Shiner perch on beds consumed more food 6 h after application than those at other time points and locations. There were no consistent differences in the diets of juvenile Chinook salmon within channels among time periods. Results suggest (1) that carbaryl applications pose little hazard to fish in the bay having habitat and dietary preferences similar to those of Shiner perch and juvenile Chinook salmon and (2) that quantification of direct exposure in the field is essential to adequately assess risk.

  13. Effects of trans-Eurasian transport of air pollutants on surface ozone concentrations over Western China

    Science.gov (United States)

    Li, Xiaoyuan; Liu, Junfeng; Mauzerall, Denise L.; Emmons, Louisa K.; Walters, Stacy; Horowitz, Larry W.; Tao, Shu

    2014-11-01

    Due to a lack of industrialization in Western China, surface air there was, until recently, believed to be relatively unpolluted. However, recent measurements and modeling studies have found high levels of ozone (O3) there. Based on the state-of-the-science global chemical transport model MOZART-4, we identify the origin, pathway, and mechanism of trans-Eurasian transport of air pollutants to Western China in 2000. MOZART-4 generally simulates well the observed surface O3 over inland areas of China. Simulations find surface ozone concentrations over Western China on average to be about 10 ppbv higher than Eastern China. Using sensitivity studies, we find that anthropogenic emissions from all Eurasian regions except China contribute 10-15 ppbv surface O3 over Western China, superimposed upon a 35-40 ppbv natural background. Transport from European anthropogenic sources to Northwestern China results in 2-6 ppbv O3 enhancements in spring and summer. Indian anthropogenic sources strongly influence O3 over the Tibetan Plateau during the summer monsoon. Transport of O3 originating from emissions in the Middle East occasionally reach Western China and increase surface ozone there by about 1-4 ppbv. These influences are of similar magnitude as trans-Pacific and transatlantic transport of O3 and its precursors, indicating the significance of trans-Eurasian ozone transport in hemispheric transport of air pollution. Our study further indicates that mitigation of anthropogenic emissions from Europe, the Indian subcontinent, and the Middle East could benefit public health and agricultural productivity in Western China.

  14. Effects of trans-Eurasian transport of anthropogenic pollutants on surface ozone concentrations over China

    Science.gov (United States)

    Liu, J.; Li, X.; Mauzerall, D. L.; Emmons, L. K.; Horowitz, L. W.; Guo, Y.; Tao, S.

    2015-12-01

    Due to a lack of industrialization in Western China, surface air there was, until recently, believed to be relatively unpolluted. However, recent measurements and modeling studies have found high levels of ozone (O3) there. Based on the state-of-the-science global chemical transport model MOZART-4, we identify the origin, pathway, and mechanism of trans-Eurasian transport of air pollutants to Western China in 2000. MOZART-4 generally simulates well the observed surface O3 over inland areas of China. Simulations find surface ozone concentrations over Western China on average to be about 10 ppbv higher than Eastern China. Using sensitivity studies as well as a fully-tagged approach, we find that anthropogenic emissions from all Eurasian regions except China contribute 10-15 ppbv surface O3 over Western China, superimposed upon a 35-40 ppbv natural background. Transport from European anthropogenic sources to Northwestern China results in 2-6 ppbv O3 enhancements in spring and summer. Indian anthropogenic sources strongly influence O3 over the Tibetan Plateau during the summer monsoon. Transport of O3 originating from emissions in the Middle East occasionally reach Western China and increase surface ozone there by about 1-4 ppbv. These influences are of similar magnitude as trans-Pacific and transatlantic transport of O3 and its precursors, indicating the significance of trans-Eurasian ozone transport in hemispheric transport of air pollution. Our study further indicates that mitigation of anthropogenic emissions from Europe, the Indian subcontinent, and the Middle East could benefit public health and agricultural productivity in Western China.

  15. Troglostrongylus brevior in an Eurasian lynx (Lynx lynx) from Bosnia and Herzegovina.

    Science.gov (United States)

    Alić, Amer; Traversa, Donato; Duscher, Georg Gerhard; Kadrić, Mirsad; Di Cesare, Angela; Hodžić, Adnan

    2015-12-21

    In the past few years the interest of the scientific community on lungworms of the genus Troglostrongylus has grown due to the increased number of unexpected cases of infections with Troglostrongylus brevior in domestic cats from Mediterranean Europe, likely due to a spill-over from wild reservoirs. Thus, there is a merit to increase our knowledge on the occurrence of this parasite in felids from European regions. The present paper describes lung lesions associated with T. brevior infection in the endangered Eurasian lynx (Lynx lynx) from Bosnia and Herzegovina. The carcass of an illegally killed 3-year-old male Eurasian lynx was presented for necropsy at the Faculty of Veterinary Medicine of Sarajevo (Bosnia and Herzegovina). Grossly, multiple, multinodular, consolidated and firm, tan to grey areas, occupying the caudal third of caudal lung lobes, were observed. At cut section, the catarrhal fluid was draining from the airways. Larvae of T. brevior were found in tracheal scraping. The histopathological examination revealed multifocal to coalescing areas, centered on bronchi and bronchioles, and expanded alveoli filled with necrotic debris, degenerated inflammatory cells, mostly neutrophils and macrophages, and multiple cross sections of parasite larvae and thin-walled morulated eggs of lungworms. The paraffin-embedded lung samples were molecularly positive for T. brevior. This paper describes the first record of T. brevior in the Eurasian lynx and the associated host lung pathology. Given its pathogenic potential and the lack of data on troglostrongylosis in lynx populations, the occurrence and impact of Troglostrongylus spp. on wildlife health as well as the role of L. lynx as reservoir of infection for other felids, should be further investigated.

  16. Genome-wide Evidence Reveals that African and Eurasian Golden Jackals Are Distinct Species.

    Science.gov (United States)

    Koepfli, Klaus-Peter; Pollinger, John; Godinho, Raquel; Robinson, Jacqueline; Lea, Amanda; Hendricks, Sarah; Schweizer, Rena M; Thalmann, Olaf; Silva, Pedro; Fan, Zhenxin; Yurchenko, Andrey A; Dobrynin, Pavel; Makunin, Alexey; Cahill, James A; Shapiro, Beth; Álvares, Francisco; Brito, José C; Geffen, Eli; Leonard, Jennifer A; Helgen, Kristofer M; Johnson, Warren E; O'Brien, Stephen J; Van Valkenburgh, Blaire; Wayne, Robert K

    2015-08-17

    The golden jackal of Africa (Canis aureus) has long been considered a conspecific of jackals distributed throughout Eurasia, with the nearest source populations in the Middle East. However, two recent reports found that mitochondrial haplotypes of some African golden jackals aligned more closely to gray wolves (Canis lupus), which is surprising given the absence of gray wolves in Africa and the phenotypic divergence between the two species. Moreover, these results imply the existence of a previously unrecognized phylogenetically distinct species despite a long history of taxonomic work on African canids. To test the distinct-species hypothesis and understand the evolutionary history that would account for this puzzling result, we analyzed extensive genomic data including mitochondrial genome sequences, sequences from 20 autosomal loci (17 introns and 3 exon segments), microsatellite loci, X- and Y-linked zinc-finger protein gene (ZFX and ZFY) sequences, and whole-genome nuclear sequences in African and Eurasian golden jackals and gray wolves. Our results provide consistent and robust evidence that populations of golden jackals from Africa and Eurasia represent distinct monophyletic lineages separated for more than one million years, sufficient to merit formal recognition as different species: C. anthus (African golden wolf) and C. aureus (Eurasian golden jackal). Using morphologic data, we demonstrate a striking morphologic similarity between East African and Eurasian golden jackals, suggesting parallelism, which may have misled taxonomists and likely reflects uniquely intense interspecific competition in the East African carnivore guild. Our study shows how ecology can confound taxonomy if interspecific competition constrains size diversification. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. The Role of Recent Admixture in Forming the Contemporary West Eurasian Genomic Landscape

    Science.gov (United States)

    Busby, George B.J.; Hellenthal, Garrett; Montinaro, Francesco; Tofanelli, Sergio; Bulayeva, Kazima; Rudan, Igor; Zemunik, Tatijana; Hayward, Caroline; Toncheva, Draga; Karachanak-Yankova, Sena; Nesheva, Desislava; Anagnostou, Paolo; Cali, Francesco; Brisighelli, Francesca; Romano, Valentino; Lefranc, Gerard; Buresi, Catherine; Ben Chibani, Jemni; Haj-Khelil, Amel; Denden, Sabri; Ploski, Rafal; Krajewski, Pawel; Hervig, Tor; Moen, Torolf; Herrera, Rene J.; Wilson, James F.; Myers, Simon; Capelli, Cristian

    2015-01-01

    Summary Over the past few years, studies of DNA isolated from human fossils and archaeological remains have generated considerable novel insight into the history of our species. Several landmark papers have described the genomes of ancient humans across West Eurasia, demonstrating the presence of large-scale, dynamic population movements over the last 10,000 years, such that ancestry across present-day populations is likely to be a mixture of several ancient groups [1, 2, 3, 4, 5, 6, 7]. While these efforts are bringing the details of West Eurasian prehistory into increasing focus, studies aimed at understanding the processes behind the generation of the current West Eurasian genetic landscape have been limited by the number of populations sampled or have been either too regional or global in their outlook [8, 9, 10, 11]. Here, using recently described haplotype-based techniques [11], we present the results of a systematic survey of recent admixture history across Western Eurasia and show that admixture is a universal property across almost all groups. Admixture in all regions except North Western Europe involved the influx of genetic material from outside of West Eurasia, which we date to specific time periods. Within Northern, Western, and Central Europe, admixture tended to occur between local groups during the period 300 to 1200 CE. Comparisons of the genetic profiles of West Eurasians before and after admixture show that population movements within the last 1,500 years are likely to have maintained differentiation among groups. Our analysis provides a timeline of the gene flow events that have generated the contemporary genetic landscape of West Eurasia. PMID:26387712

  18. [Social play in the development of sibling relations in Eurasian lynx (Lynx lynx)].

    Science.gov (United States)

    Alekseeva, G S; Antonevich, A L; Erofeeva, M N; Naĭdenko, S V

    2014-01-01

    Social play fulfills an important function in creating and maintaining relations between siblings. However, its relationship with the intralitter social processes is poorly understood. It was noticed that, in Eurasian lynx (Lynx lynx) litters, sex differences in social play are absent in the first 2-3 months of life. Itwas found that the most intense periods of play behavior (at an age of 9 and 1-2 weeks) coincide with periods of aggression. Gradual change in play interactions, which require close physical contact by play elements with increased motor activity, are described. This reflects the changes in the relevance of certain skills of lynx cubs as they grow older.

  19. Course of Russian History for Foreigners as an Instrument of Eurasian Integration

    Directory of Open Access Journals (Sweden)

    R A Arslanov

    2014-12-01

    Full Text Available The article considers the significance of teaching the course of history as a means, that can influence the integration process in CIS countries. It is noted that the studying of traditions and culture of the host country helps them to adapt to Russian social life. Besides, it is emphasized that the general historical knowledge creates the condition for overcoming ethnic and cultural barriers and it becomes one of the spiritual factors of Eurasian integration. Particular attention is paid to the content of the course in which specific historical examples show that Russia was founded and developed through the unity and interaction of different nations, traditions and cultures.

  20. Revealing turning points in ecosystem functioning over the Northern Eurasian agricultural frontier

    DEFF Research Database (Denmark)

    Horion, Stéphanie Marie Anne F; Prishchepov, Alexander; Verbesselt, Jan

    2016-01-01

    The collapse of the Soviet Union in 1991 has been a turning point in the World history that left a unique footprint on the Northern Eurasian ecosystems. Conducting large scale mapping of environmental change and separating between naturogenic and anthropogenic drivers is a difficult endeavor...... affected vegetation productivity throughout the observation period, with a general worsening of the drought conditions in recent years. Moreover, recent human-induced turning points in ecosystem functioning were detected and attributed to ongoing recultivation and change in irrigation practices...

  1. Abandoned Clay Mines: An Opportunity For Eurasian Otters In NW Spain

    OpenAIRE

    César Ayres; Pablo García

    2009-01-01

    The Eurasian otter (Lutra lutra) is widely distributed in the north of the Iberian Peninsula, supposedly one of the best populations of Spain. Usually otters inhabit coastal and riverine habitats in this region, but in some cases they use man-made habitats. In the last three winters the seasonal use of old clay pits by otters has been studied in a locality from Galicia. The abundance of these artificial habitats could lead to a recolonization of Gandaras de Budiño and Ribeiras do Louro wetlan...

  2. The Eurasian Model of International Labour Legislation in the Context of Globalization

    Directory of Open Access Journals (Sweden)

    Andrey Lushnikov

    2016-01-01

    Full Text Available The current article seeks to provide a comparative legal analysis of the Eurasian model of international labor legislation. It explores the multi-layered nature of contemporary international labor law in the context of globalization and regionalization, emphasizing the growing importance of cross-border legal labor standards in regional structures in the early 21st century and defines how global and regional cross-border legislation is incorporated on the basis of in favorem. The authors propose their own original concept of international labor legislation, based on the four characteristics: 1 The overall aim of legal regulation; 2 The extent of integration within those regulations; 3 Sources of labor law and their characteristics; 4 Systems of international control over labor rights. To define an original model for the legal regulation of labor, the authors investigate case studies of labour legal regulation in inter-state regional organizations including the European Union, the Council of Europe and ASEAN. The authors’ theoretical model identifies the defining features of Eurasia’s model of labor regulation. The research also follows the establishment and development of Eurasian labor law and attempts to give an informed judgment about its future path. In their conclusions, the authors assert that modern Eurasian labor law is a ‘live law’, still under development as it incorporates the non-uniform integration between the former Soviet Republics. Two primary trends leading regional co-operation in the labor market are identified: 1 A social model, implementing international labor rights across Eurasia; 2 An economic model, built on the free movement of labor in a common market. In today’s environment, the Commonwealth of Independent States goes some way toward representing the first trend through its attempts to serve as an international coordinating organization. The second trend is supported by supranational organizations promoting

  3. Standardized Interpretation of Chest Radiographs in Cases of Pediatric Pneumonia From the PERCH Study

    Science.gov (United States)

    Deloria Knoll, Maria; Barger-Kamate, Breanna; de Campo, John; de Campo, Margaret; Diallo, Mahamadou; Ebruke, Bernard E.; Feikin, Daniel R.; Gleeson, Fergus; Gong, Wenfeng; Hammitt, Laura L.; Izadnegahdar, Rasa; Kruatrachue, Anchalee; Madhi, Shabir A.; Manduku, Veronica; Matin, Fariha Bushra; Mahomed, Nasreen; Moore, David P.; Mwenechanya, Musaku; Nahar, Kamrun; Oluwalana, Claire; Ominde, Micah Silaba; Prosperi, Christine; Sande, Joyce; Suntarattiwong, Piyarat; O’Brien, Katherine L.

    2017-01-01

    Abstract Background. Chest radiographs (CXRs) are a valuable diagnostic tool in epidemiologic studies of pneumonia. The World Health Organization (WHO) methodology for the interpretation of pediatric CXRs has not been evaluated beyond its intended application as an endpoint measure for bacterial vaccine trials. Methods. The Pneumonia Etiology Research for Child Health (PERCH) study enrolled children aged 1–59 months hospitalized with WHO-defined severe and very severe pneumonia from 7 low- and middle-income countries. An interpretation process categorized each CXR into 1 of 5 conclusions: consolidation, other infiltrate, both consolidation and other infiltrate, normal, or uninterpretable. Two members of a 14-person reading panel, who had undertaken training and standardization in CXR interpretation, interpreted each CXR. Two members of an arbitration panel provided additional independent reviews of CXRs with discordant interpretations at the primary reading, blinded to previous reports. Further discordance was resolved with consensus discussion. Results. A total of 4172 CXRs were obtained from 4232 cases. Observed agreement for detecting consolidation (with or without other infiltrate) between primary readers was 78% (κ = 0.50) and between arbitrators was 84% (κ = 0.61); agreement for primary readers and arbitrators across 5 conclusion categories was 43.5% (κ = 0.25) and 48.5% (κ = 0.32), respectively. Disagreement was most frequent between conclusions of other infiltrate and normal for both the reading panel and the arbitration panel (32% and 30% of discordant CXRs, respectively). Conclusions. Agreement was similar to that of previous evaluations using the WHO methodology for detecting consolidation, but poor for other infiltrates despite attempts at a rigorous standardization process. PMID:28575359

  4. Adding perches for cross-pollination ensures the reproduction of a self-incompatible orchid.

    Directory of Open Access Journals (Sweden)

    Zhong-Jian Liu

    Full Text Available BACKGROUND: Outcrossing is known to carry genetic advantages in comparison with inbreeding. In many cases, flowering plants develop a self-incompatibility mechanism, along with a floral component adaptation mechanism, to avoid self-pollination and to promote outbreeding. Orchids commonly have a lip in their flower that functions as the a visiting plate for insect pollinators. Aside from the lip, however, many species (including Coelogyne rigida have sheaths around the axis of inflorescence. The function of these sheaths remains unknown, and has long been a puzzle to researchers. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the function of these sheaths in relation to the lip and the pollinators, as well as their role in the modes of pollination and reproduction of Coelogyne rigida in 30 flowering populations of orchids in the limestone area of Southeast Yunnan, China. We found that self-incompatible C. rigida developed specialized bird perches around the basal axis of inflorescence to attract sunbirds and to complement their behavioral tendency to change foraging locations frequently. This self-incompatibility mechanism operates separately from the floral component adaptation mechanism. This mechanism thus prevents bees from repeatedly visiting the floral lip of the same plant which, in turn, results in autogamy. In this way, instead of preventing autogamy, C. rigida responds to these negative effects through a highly efficient cross-pollination method that successfully transfers pollen to different plants. CONCLUSIONS: The proposed method ensures reproductive success, while offsetting the infertile self-pollination by insects, thereby reducing mating costs and addressing the lack of cross-pollination. The adaptation provides a novel and striking example of structural adaptation that promotes cross-pollination in angiosperms.

  5. Introducing a new Book on the Ural-Altaic Language Classification (Towards Eurasian Linguistic Isoglosses: the Case of Turkic and Hungarian)

    NARCIS (Netherlands)

    Marácz, L.

    2014-01-01

    In this article, László Marácz introduces his own book on a new approach to the Ural-Altaic language classification. The book entitled ‘Towards Eurasian Linguistic Isoglosses: the Case of Hungarian and Turkic’ (henceforth ‘Towards Eurasian Linguistic Isoglosses…’ abbreviated as TELI) develops a

  6. Bone-Remodeling Transcript Levels Are Independent of Perching in End-of-Lay White Leghorn Chickens

    Directory of Open Access Journals (Sweden)

    Maurice D. Dale

    2015-01-01

    Full Text Available Osteoporosis is a bone disease that commonly results in a 30% incidence of fracture in hens used to produce eggs for human consumption. One of the causes of osteoporosis is the lack of mechanical strain placed on weight-bearing bones. In conventionally-caged hens, there is inadequate space for chickens to exercise and induce mechanical strain on their bones. One approach is to encourage mechanical stress on bones by the addition of perches to conventional cages. Our study focuses on the molecular mechanism of bone remodeling in end-of-lay hens (71 weeks with access to perches. We examined bone-specific transcripts that are actively involved during development and remodeling. Using real-time quantitative PCR, we examined seven transcripts (COL2A1 (collagen, type II, alpha 1, RANKL (receptor activator of nuclear factor kappa-B ligand, OPG (osteoprotegerin, PTHLH (PTH-like hormone, PTH1R (PTH/PTHLH type-1 receptor, PTH3R (PTH/PTHLH type-3 receptor, and SOX9 (Sry-related high mobility group box in phalange, tibia and femur. Our results indicate that the only significant effect was a difference among bones for COL2A1 (femur > phalange. Therefore, we conclude that access to a perch did not alter transcript expression. Furthermore, because hens have been used as a model for human bone metabolism and osteoporosis, the results indicate that bone remodeling due to mechanical loading in chickens may be a product of different pathways than those involved in the mammalian model.

  7. Elevated temperature and acclimation time affect metabolic performance in the heavily exploited Nile perch of Lake Victoria.

    Science.gov (United States)

    Nyboer, Elizabeth A; Chapman, Lauren J

    2017-10-15

    Increasing water temperatures owing to anthropogenic climate change are predicted to negatively impact the aerobic metabolic performance of aquatic ectotherms. Specifically, it has been hypothesized that thermal increases result in reductions in aerobic scope (AS), which lead to decreases in energy available for essential fitness and performance functions. Consequences of warming are anticipated to be especially severe for warm-adapted tropical species as they are thought to have narrow thermal windows and limited plasticity for coping with elevated temperatures. In this study we test how predicted warming may affect the aerobic performance of Nile perch (Lates niloticus), a commercially harvested fish species in the Lake Victoria basin of East Africa. We measured critical thermal maxima (CTmax) and key metabolic variables such as AS and excess post-exercise oxygen consumption (EPOC) across a range of temperatures, and compared responses between acute (3-day) exposures and 3-week acclimations. CTmax increased with acclimation temperature; however, 3-week-acclimated fish had higher overall CTmax than acutely exposed individuals. Nile perch also showed the capacity to increase or maintain high AS even at temperatures well beyond their current range; however, acclimated Nile perch had lower AS compared with acutely exposed fish. These changes were accompanied by lower EPOC, suggesting that drops in AS may reflect improved energy utilization after acclimation, a finding that is supported by improvements in growth at high temperatures over the acclimation period. Overall, the results challenge predictions that tropical species have limited thermal plasticity, and that high temperatures will be detrimental because of limitations in AS. © 2017. Published by The Company of Biologists Ltd.

  8. Monitoring testicular activity of male Eurasian (Lynx lynx) and Iberian (Lynx pardinus) lynx by fecal testosterone metabolite measurement.

    Science.gov (United States)

    Jewgenow, K; Naidenko, S V; Goeritz, F; Vargas, A; Dehnhard, M

    2006-11-01

    The aim of the present study was to identify relevant fecal testosterone metabolites in the Eurasian lynx (Lynx lynx) using HPLC analysis and to evaluate the specificity of two testosterone immunoassays against these fecal metabolites. Finally, fecal hormone analysis was used to characterize seasonal reproductive activity of captive male Eurasian and Iberian (Lynx pardinus) lynx. Fecal samples from a male Eurasian lynx who received an i.v. injection of [3H]testosterone were subjected to HPLC analysis. All HPLC fractions were analyzed for radioactivity and androgen content by two testosterone immune assays (EIA and Testosterone-Immulite kits, DPC Biermann, Germany). Furthermore, fecal samples from four Eurasian lynx males (n=174) and three Iberian lynx (n=52) were collected throughout the year and fecal testosterone metabolites were determined with Testosterone-Immulite assay. HPLC separation of radiolabeled Eurasian lynx fecal extract indicated that the majority of testosterone metabolites are substances with a higher polarity than testosterone. Only minor proportion of radioactivity co-eluted with authentic testosterone and dihydrotestosterone. Enzymatic hydrolysis and solvolysis of the fecal extract were insufficient to liberate testosterone. After solvolysis relatively more activity was eluated the position of DHT, but the majority of metabolites remained unaffected. The EIA measured substantial amount of immunoreactivity, which corresponded with two radioactive peaks. Additionally, both immunoassays recognized two metabolites, which were only minor components according to their radioactivity. The Immulite assay was able to recognize a metabolite at the position of dihydrotestosterone. HPLC separation of Iberian lynx feces extracts revealed a similar metabolite pattern determined by EIA that were typical for Eurasian lynx fecal extracts. Simultaneous analyses of fecal samples with both testosterone assays provided comparative results for both lynx species

  9. Nesting, dust bathing and perching by laying hens in cages: effects of design on behaviour and welfare.

    Science.gov (United States)

    Appleby, M C; Smith, S F; Hughes, B O

    1993-12-01

    1. Laying hens (192 ISA Brown medium hybrids) were housed from 18 to 72 weeks as groups of 4 in conventional or experimental cages. The main area of all cages provided 675 cm2/hen. All experimental cages had perches, dust baths and nest boxes, which were of three types: litter (L), artificial turf (A) or plastic rollaway (P). These facilities provided an additional 375 to 480 cm2/hen. The nest boxes and dust baths occupied either high or low positions. Behaviour, physical condition and production of the birds were regularly recorded. 2. Mortality was low (1.6% overall) and egg production very good in all treatments. The proportion of cracked and dirty eggs was slightly (but not significantly) higher in the experimental cages. In the experimental cages 90% of eggs were laid overall in the nest boxes and 3% in the dust baths. The proportion laid in the nest boxes was lower early in the laying cycle and increased with time, reaching 99% in A. 3. The facilities were heavily used. Birds spent about 25% of day time on the perches and 10-15% in or near the nest box and dust bath. At night, the majority of birds (90 to 94%) roosted on perches, but most of the remainder were on the lips of the nest box or dust bath, fouling the interiors. 4. Pre-laying behaviour was much more settled in the experimental cages (45 min spent in the eventual laying position) than in the conventional ones (20 min) and total duration varied from 68 min in A to 87 min in P. The number of nest entries varied from 3.0 (A and P) to 4.3 (L); disturbance to sitting birds was correspondingly greater in L. 5. Dust bathing in the experimental cages generally took place during the afternoon in a single bout of about 5 min duration, whereas in the conventional cages it was brief and fragmented (3 bouts of 10 s each). The dust bath was also used for foraging behaviour (pecking and scratching). The treatments with small dust baths (A and P) caused problems for the birds. 6. Feather, foot and claw damage all

  10. Space use by 4 strains of laying hens to perch, wing flap, dust bathe, stand and lie down.

    Science.gov (United States)

    Riddle, Elizabeth R; Ali, Ahmed B A; Campbell, Dana L M; Siegford, Janice M

    2018-01-01

    The laying hen industry is implementing aviary systems intended to improve welfare by providing hens with more space and resources to perform species-specific behaviors. To date, limited research has examined spatial requirements of various strains of laying hens for performing key behaviors and none has been conducted within an alternative housing system. This study investigated the amount of space used by 4 strains of laying hens (Hy-Line Brown [HB], Bovans Brown [BB], DeKalb White [DW], and Hy-Line W36) to perform 5 different behaviors in the litter area of a commercial-style aviary. Hens were recorded standing [S], lying [L], perching [P], wing flapping [WF], and dust bathing [DB] on an open-litter area with an outer perch between 12:00 and 15:00 at peak lay (28 wk of age). Still images of each behavior were analyzed using ImageJ software for 16 hens per strain, and maximum hen length and width were used to calculate total area occupied per hen for each behavior. Brown hens required, on average, 89.6cm2 more space for S (P≤0.021) and 81.5cm2 more space for L (P≤0.013) than white hens. White hens used, on average, 572cm2 more space to perform WF than brown hens (P≤0.024) while brown hens used 170.3cm2 more space for DB than white hens (P≤0.022). On average, hens of all strains were wider while perching than the 15cm commonly recommended per hen (e.g., DW: 18.03; HB: 21.89cm), and brown hens required, on average, 3.38cm more space while perching than white hens (P≤0.01). Brown and white hens occupy different amounts of space when performing key behaviors. These differences, along with factors such as behavioral synchrony, clustering, and preferred inter-bird distances associated with these behaviors, should be considered when creating industry guidelines, crafting legislation and designing and stocking laying hen facilities to ensure hens can fulfill their behavioral needs.

  11. Isolationism versus Geopolitics: The Dual Role of the Eurasian Economic Union in Global Governance

    Directory of Open Access Journals (Sweden)

    Maxim Bratersky

    2016-09-01

    Full Text Available This article conceptualizes ongoing efforts to develop the Eurasian Economic Union (EEU, initiated by Russia, Belarus and Kazakhstan in 2011. Engaging with two major theoretical perspectives, it establishes to what extent the EEU’s construction and potential expansion is economic regionalism (interpreted also as an isolationist strategy driven by Russia led geopolitical motives. The political-economy debate of Eurasia goes beyond a common tariff area and a common market within the territory of the former USSR. Increasingly, it involves the establishment of a common monetary area. China’s Silk Road Economic Belt is building a foundation for a new Eurasia – one of the global economic and political players of this century. The economic reasons pursued by Russia in its Eurasian initiative are inseparable from economic problems of geopolitical significance. The overarching objective of Russian policy is to establish a regional economic fusion, with significant economic sovereignty and strong political influence; that is, to become the new centre of power in the global economy of the 21st century. Correspondingly, although Russian integration policy in Eurasia has not been formulated in an anti-American way, if it is successful the likely consequence will be the withdrawal of a significant segment of the global market from the economic dominance and political influence of western-led economic blocs.

  12. Critical steps to ensure the successful reintroduction of the Eurasian red squirrel

    Directory of Open Access Journals (Sweden)

    Vieira, B. P

    2015-04-01

    Full Text Available Wildlife reintroduction strategies aim to establish viable long–term populations, promote conservation awareness and provide economic benefits for local communities. In Portugal, the Eurasian red squirrel (Sciurus vulgaris became extinct in the 16th century and was reintroduced in urban parks in the 1990s, mainly for aesthetic and leisure purposes. We evaluated the success of this reintroduction in two urban parks and here described the critical steps. We assessed habitat use, population density and abundance, and management steps carried out during reintroduction projects. Reintroductions have been successful to some extent given squirrels are present 20 years after release. However, populations in both parks are declining due to the lack of active management and poor quality habitat. Successful reintroduction of Eurasian red squirrel in areas without competition of alien tree squirrels involves three critical main stages. The pre–project stage includes studies on habitat quality, genetic proximity between donors and closest wild population, and health of donor stocks. In the release stage, the number of individuals released will depend on resource variability, and the hard release technique is an effective and economically viable method. Post–release activities should evaluate adaptation, mitigate mortality, monitor the need for supplementary feeding, provide veterinary support, and promote public awareness and education.

  13. The Eurasian Economic Union and the Silk Road Economic Belt: Players, Interests and Implementation Challenges

    Directory of Open Access Journals (Sweden)

    Andrei Skriba

    2016-11-01

    Full Text Available In May 2015, Russia and China coordinated their activities in Central Asia and decided to connect the Eurasian EconomicUnion (EEU and the Silk Road Economic Belt. This decision seemed to prevent unnecessary competition between these two basically non-conflicting projects. However, in time there appeared a lack of understanding of this combined endeavour and its implementation mechanisms. It is still unclear how further dialogue between the EEU and the Silk Road will proceed. There is no consensuson the participation of the EEU members and the Eurasian Economic Commission. Without a clear strategy, the Russian-Chinese agreement has started to lose momentum. Some non-regional players can benefit from this – of course, in their own interests.This articles attempt to explain the threats posed by delay and inaction in the combined EEU and Silk Road projects, and to describe the potential benefits of actively implementing the combination. It then proposes a concrete format for such a combination, its priority areas, as well as mechanisms for implementation.

  14. Caching at a distance: a cache protection strategy in Eurasian jays.

    Science.gov (United States)

    Legg, Edward W; Ostojić, Ljerka; Clayton, Nicola S

    2016-07-01

    A fundamental question about the complexity of corvid social cognition is whether behaviours exhibited when caching in front of potential pilferers represent specific attempts to prevent cache loss (cache protection hypothesis) or whether they are by-products of other behaviours (by-product hypothesis). Here, we demonstrate that Eurasian jays preferentially cache at a distance when observed by conspecifics. This preference for a 'far' location could be either a by-product of a general preference for caching at that specific location regardless of the risk of cache loss or a by-product of a general preference to be far away from conspecifics due to low intra-species tolerance. Critically, we found that neither by-product account explains the jays' behaviour: the preference for the 'far' location was not shown when caching in private or when eating in front of a conspecific. In line with the cache protection hypothesis we found that jays preferred the distant location only when caching in front of a conspecific. Thus, it seems likely that for Eurasian jays, caching at a distance from an observer is a specific cache protection strategy.

  15. Mitochondrial DNA Suggests a Western Eurasian Origin for Ancient (Proto-) Bulgarians.

    Science.gov (United States)

    Nesheva, D V; Karachanak-Yankova, S; Lari, M; Yordanov, Y; Galabov, A; Caramelli, D; Toncheva, D

    2015-01-01

    Ancient (proto-) Bulgarians have long been thought of as a Turkic population. However, evidence found in the past three decades shows that this is not the case. Until now, this evidence has not included ancient mitochondrial DNA (mtDNA) analysis. To fill this void, we collected human remains from the 8th to the 10th century AD located in three necropolises in Bulgaria: Nojarevo (Silistra region) and Monastery of Mostich (Shumen region), both in northeastern Bulgaria, and Tuhovishte (Satovcha region) in southwestern Bulgaria. The phylogenetic analysis of 13 ancient DNA samples (extracted from teeth) identified 12 independent haplotypes, which we further classified into mtDNA haplogroups found in present-day European and western Eurasian populations. Our results suggest a western Eurasian matrilineal origin for proto-Bulgarians, as well as a genetic similarity between proto- and modern Bulgarians. Our future work will provide additional data that will further clarify proto-Bulgarian origins, thereby adding new clues to the current understanding of European genetic evolution.

  16. WHITHER DEVELOPMENT? THE EFFECTS OF THE EURASIAN UNION ON THE CENTRAL ASIAN REPUBLICS

    Directory of Open Access Journals (Sweden)

    Adelin Dumitru

    2015-12-01

    Full Text Available In this paper I analyze the impact of the Eurasian Union on the Central Asian republics, with a focus on remittances trends. To this end I review at first the literature regarding the effects of the Customs Union on its members. Then, I assess the current state of the economies most likely to be affected by membership in the Eurasian Union, i.e. Tajikistan and Kyrgyzstan, whose specificity is their dependency on remittances. Secondly, I present a plausible scenario in regard to the influence of the formalization of this regional organization on the emerging Central Asian regional security subcomplex. I argue that the EEU is a hindrance towards the five Central Asian Republics’ evolving towards a regional security complex. Not only has it already distorted trade in the region, but it can also turn some presently frozen conflicts into security hotspots. I hold that the only way to spur development in the region is, internally, to diversify the economy, and, externally, to bring the five republics closer. I try to show that the Central Asian Republics should simultaneously pursue a switch from a balance of threat to regional integration and sustainable national development. Nonetheless, the EEU will have at best mixed effects when it comes to these necessities. Alternatively, China and the New Silk Road initiative that it endorses might contribute to de-securitizing some of the existing issues.

  17. Free-ranging Eurasian lynx (Lynx lynx) as host of Toxoplasma gondii in Finland.

    Science.gov (United States)

    Jokelainen, Pikka; Deksne, Gunita; Holmala, Katja; Näreaho, Anu; Laakkonen, Juha; Kojola, Ilpo; Sukura, Antti

    2013-07-01

    We investigated the presence of Toxoplasma gondii infections in Eurasian lynx (Lynx lynx) in Finland by analyzing samples from 337 lynx that were legally hunted during the 2010-2011 season and by performing a retrospective nationwide database search of postmortem toxoplasmosis diagnoses in this species. We detected specific anti-T. gondii IgG antibodies in 290 (86.1%) of the 337 lynx. The method used was a direct agglutination test, and samples positive at the used dilution 1:40 were defined as antibody positive. Older lynx had 14.3 times higher odds of being antibody-positive than did lynx of the presumed age of 7-10 mo, and lynx weighing >15 kg had 16.7 times higher odds of being antibody positive than did those ≤ 15 kg. Lynx from the southwest were more often antibody positive, with an odds ratio 6.3, than lynx from the northeast. None of the 332 fecal samples available was positive for the presence of T. gondii-like oocysts with a quantitative MgSO4 flotation technique, and none of the 167 free-ranging Eurasian lynx examined postmortem by veterinary pathologists from January 2000 to May 2010 had died from toxoplasmosis. Although Finnish lynx were confirmed to commonly encounter T. gondii, we found no evidence of an ongoing contribution to the environmental oocyst burden nor of the lynx dying from the infection.

  18. Histomorphological features of the tongue of the Eurasian teal (Anas crecca).

    Science.gov (United States)

    Marzban Abbasabadi, B; Sayrafi, R

    2017-12-04

    This study presents the histomorphological features of tongue in Eurasian teal (Anas crecca); the smallest extant dabbling duck. Heads of four adult males and four adult females were used in this study. The results illustrate a tongue with three different parts; the apex with a lingual nail in ventral surface, the body with a lingual prominence in caudal part and some large and small conical papillae in lateral sides and the root, that was covered with many conical papillae in different sizes. Histological results revealed two types of keratinized and non-keratinized epithelium covering parts of the tongue. The lingual salivary glands were observed in the lamina propria of the body and root of the tongue showed strongly periodic acid-Schiff (PAS)-positive reaction. The yellow adipose tissue was located under the lamina propria on the body and root of the tongue. The filiform papillae between the conical papillae of the body were arranged densely. The sensory organs, which contain sensory receptors (Grandry and Herbst corpuscles), were located in the lamina propria of the body of the tongue. In conclusion, the anatomical and histological structure of the Eurasian teal' tongue was generally similar to its family members such as domestic goose and duck but showed some differences that may be adoptions to the bird's habitat and mode of feeding. © 2017 Blackwell Verlag GmbH.

  19. Sexual dimorphism of the Eurasian otter (Lutra lutra) in South Korea: Craniodental geometric morphometry.

    Science.gov (United States)

    Lau, Alice Ching Ching; Asahara, Masakazu; Han, Sung Yong; Kimura, Junpei

    2016-07-01

    Sexual dimorphism of the craniodental morphology of the Eurasian otter in South Korea was studied with geometric morphometrics. 29 adult skulls (15 males and 14 females) were used. Images of the dorsal and ventral view of the cranium and right lateral view of the mandible were taken and then digitized, and measurements were taken on the right side. Results showed that size difference between males and females was significant. Correlations between the size and shape variations have not been observed in this study. The bivariate plots with centroid size showed size dimorphism between males and females with some overlapping. Most relative warp (RW) scores were not significantly different between males and females. We observed only RW2 for dorsal and ventral view of the skull, and only RW1 for mandible was significantly different between the sexes. Shape dimorphisms were revealed at the postorbital constriction, temporal-mandibular joint, coronoid process, mandibular condyle and angular process of the skull. Based on our study, sexual dimorphism exists in Eurasian otter from the South Korean population in terms of both the size and shape. Furthermore, the degree of size dimorphism is greater than shape dimorphism.

  20. Simulating Changes in Fires and Ecology of the 21st Century Eurasian Boreal Forests of Siberia

    Directory of Open Access Journals (Sweden)

    Ksenia Brazhnik

    2017-02-01

    Full Text Available Wildfires release the greatest amount of carbon into the atmosphere compared to other forest disturbances. To understand how current and potential future fire regimes may affect the role of the Eurasian boreal forest in the global carbon cycle, we employed a new, spatially-explicit fire module DISTURB-F (DISTURBance-Fire in tandem with a spatially-explicit, individually-based gap dynamics model SIBBORK (SIBerian BOReal forest simulator calibrated to Krasnoyarsk Region. DISTURB-F simulates the effect of forest fire on the boreal ecosystem, namely the mortality of all or only the susceptible trees (loss of biomass, i.e., carbon within the forested landscape. The fire module captures some important feedbacks between climate, fire and vegetation structure. We investigated the potential climate-driven changes in the fire regime and vegetation in middle and south taiga in central Siberia, a region with extensive boreal forest and rapidly changing climate. The output from this coupled simulation can be used to estimate carbon losses from the ecosystem as a result of fires of different sizes and intensities over the course of secondary succession (decades to centuries. Furthermore, it may be used to assess the post-fire carbon storage capacity of potential future forests, the structure and composition of which may differ significantly from current Eurasian boreal forests due to regeneration under a different climate.

  1. Remarkable link between projected uncertainties of Arctic sea-ice decline and winter Eurasian climate

    Science.gov (United States)

    Cheung, Hoffman H. N.; Keenlyside, Noel; Omrani, Nour-Eddine; Zhou, Wen

    2018-01-01

    We identify that the projected uncertainty of the pan-Arctic sea-ice concentration (SIC) is strongly coupled with the Eurasian circulation in the boreal winter (December-March; DJFM), based on a singular value decomposition (SVD) analysis of the forced response of 11 CMIP5 models. In the models showing a stronger sea-ice decline, the Polar cell becomes weaker and there is an anomalous increase in the sea level pressure (SLP) along 60°N, including the Urals-Siberia region and the Iceland low region. There is an accompanying weakening of both the midlatitude westerly winds and the Ferrell cell, where the SVD signals are also related to anomalous sea surface temperature warming in the midlatitude North Atlantic. In the Mediterranean region, the anomalous circulation response shows a decreasing SLP and increasing precipitation. The anomalous SLP responses over the Euro-Atlantic region project on to the negative North Atlantic Oscillation-like pattern. Altogether, pan-Arctic SIC decline could strongly impact the winter Eurasian climate, but we should be cautious about the causality of their linkage.

  2. Pilfering Eurasian jays use visual and acoustic information to locate caches.

    Science.gov (United States)

    Shaw, Rachael C; Clayton, Nicola S

    2014-11-01

    Pilfering corvids use observational spatial memory to accurately locate caches that they have seen another individual make. Accordingly, many corvid cache-protection strategies limit the transfer of visual information to potential thieves. Eurasian jays (Garrulus glandarius) employ strategies that reduce the amount of visual and auditory information that is available to competitors. Here, we test whether or not the jays recall and use both visual and auditory information when pilfering other birds' caches. When jays had no visual or acoustic information about cache locations, the proportion of available caches that they found did not differ from the proportion expected if jays were searching at random. By contrast, after observing and listening to a conspecific caching in gravel or sand, jays located a greater proportion of caches, searched more frequently in the correct substrate type and searched in fewer empty locations to find the first cache than expected. After only listening to caching in gravel and sand, jays also found a larger proportion of caches and searched in the substrate type where they had heard caching take place more frequently than expected. These experiments demonstrate that Eurasian jays possess observational spatial memory and indicate that pilfering jays may gain information about cache location merely by listening to caching. This is the first evidence that a corvid may use recalled acoustic information to locate and pilfer caches.

  3. Transregionalism: Underlying Concept of EAEU-ASEAN Cooperation and Greater Eurasian Partnership

    Directory of Open Access Journals (Sweden)

    Anna A. Garmash

    2017-01-01

    Full Text Available Nowadays the EAEU seeks to integrate itself into the global economy as one of its regional economic centers. Developing ties with other regional integration groups corresponds the EAEU’s interests and facilitates the polycentric structure of the emerging world order. In this respect, in 2016 on the sidelines of the third Russia-ASEAN Summit Russian President Vladimir Putin proposed to develop stronger relations between the EAEU and ASEAN as well as to form a greater Eurasian partnership encompassing the EAEU, the SCO and ASEAN. While geographically vast, these projects lack conceptual underpinning. It is deemed that transregionalism – an international phenomenon which is insuffi ciently explored by both Western and Russian scholars, can provide a crucial theoretical foundation for these initiatives. The author compares the mechanisms which ASEAN employs to promote transregional cooperation with the EU, MERCOSUR and the GCC as well as within the frameworks of such dialogue platforms as ASEM and FEALAC. The author suggests that EAEU-ASEAN relations should be analyzed from the viewpoint of a classic transregionalism, while a greater Eurasian partnership seen as an example of a broader one. The results of the analysis are instrumental in laying out practical recommendations for the EAEU in carrying out its transregional agenda.

  4. Field-Derived Hydraulic Properties for Perched-Water Aquifer Wells 299-E33-350 and 299-E33-351, Hanford Site B-Complex Area

    Energy Technology Data Exchange (ETDEWEB)

    Newcomer, Darrell R.

    2014-07-01

    During February and March 2014, Pacific Northwest National Laboratory conducted hydraulic (slug) tests at 200-DV-1 Operable Unit wells 299-E33-350 (C8914) and 299-E33-351 (C8915) as part of B-Complex Area Perched-Water characterization activities at the Hanford Site 200-East Area. During the construction/completion phase of each well, two overlapping depth intervals were tested within the unconfined perched-water aquifer contained in the silty-sand subunit of the Cold Creek Unit. The purpose of the slug-test characterization was to provide estimates of transmissivity and hydraulic conductivity for the perched-water aquifer at these selected well locations.

  5. Identification and profiling of growth-related microRNAs in Chinese perch (Siniperca chuatsi).

    Science.gov (United States)

    Tu, Jiagang; Tian, Changxu; Zhao, Peiqi; Sun, Junxiao; Wang, Min; Fan, Qixue; Yuan, Yongchao

    2017-06-28

    MicroRNAs (miRNAs) are endogenous small non-coding RNAs that play important roles in the regulation of diverse biological processes in eukaryotes. Chinese perch (Siniperca chuatsi) is one of the most economically important fish species widely cultured in China. Growth is an extremely important characteristic in fish. Individual differences in body size are common in Siniperca chuatsi, which significantly influence the aquaculture production of Siniperca chuatsi. However, the underline growth-related regulatory factors, such as miRNAs, are still unknown. To investigate the growth-related miRNAs in Siniperca chuatsi, two RNA libraries from four growth-related tissues (brain, pituitary, liver, and muscle) of Siniperca chuatsi at 6-month stage with relatively high or low growth rates (big-size group or small-size group) were obtained and sequenced using Solexa sequencing. A total of 252 known miRNAs and 12 novel miRNAs were identified. The expression patterns of these miRNAs in big-size group and small-size group were compared, and the results showed that 31 known and 5 novel miRNAs were differently expressed (DE). Furthermore, to verify the Solexa sequencing, five DE miRNAs were randomly selected and quantified by quantitative reverse transcription polymerase chain reaction (qRT-PCR). The results showed that their expression patterns were consistent with those of Solexa sequencing. In addition, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of target genes of DE miRNAs was performed. It showed that the target genes were involved in multiple biological processes including metabolic process, suggesting that metabolic process played an important role in growth of fish. Siniperca chuatsi is a popular and economically important species in aquaculture. In this study, miRNAs in Siniperca chuatsi with different growth rates were identified, and their expression profiles were compared. The data provides the first large-scale mi

  6. Less is more: extreme genome complexity reduction with ddRAD using Ion Torrent semiconductor technology.

    Science.gov (United States)

    Pukk, Lilian; Ahmad, Freed; Hasan, Shihab; Kisand, Veljo; Gross, Riho; Vasemägi, Anti

    2015-09-01

    Massively parallel sequencing a small proportion of the whole genome at high coverage enables answering a wide range of questions from molecular evolution and evolutionary biology to animal and plant breeding and forensics. In this study, we describe the development of restriction-site associated DNA (RAD) sequencing approach for Ion Torrent PGM platform. Our protocol results in extreme genome complexity reduction using two rare-cutting restriction enzymes and strict size selection of the library allowing sequencing of a relatively small number of genomic fragments with high sequencing depth. We applied this approach to a common freshwater fish species, the Eurasian perch (Perca fluviatilis L.), and generated over 2.2 MB of novel sequence data consisting of ~17,000 contigs, identified 1259 single nucleotide polymorphisms (SNPs). We also estimated genetic differentiation between the DNA pools from freshwater (Lake Peipus) and brackish water (the Baltic Sea) populations and identified SNPs with the strongest signal of differentiation that could be used for robust individual assignment in the future. This work represents an important step towards developing genomic resources and genetic tools for the Eurasian perch. We expect that our ddRAD sequencing protocol for semiconductor sequencing technology will be useful alternative for currently available RAD protocols. © 2015 The Authors. Molecular Ecology Resources published by John Wiley & Sons Ltd.

  7. Ecological carryover effects associated with partial migration in white perch (Morone americana) within the Hudson River Estuary

    Science.gov (United States)

    Gallagher, Brian K.; Piccoli, Philip M.; Secor, David H.

    2018-01-01

    Partial migration in complex life cycles allows environmental conditions experienced during one life-stage to interact with genetic thresholds and produce divergent spatial behaviors in the next stage. We evaluated partial migration over the entire life cycle of white perch, (Morone americana) within the Hudson River Estuary, combining otolith microchemistry, population demographics and environmental data analysis. Ecological carryover effects were used as a framework to test how environmental variation during the larval period influenced migration behaviors and growth characteristics in subsequent life-stages. Two annual cohorts of juveniles were classified based on whether they persisted in natal habitats (freshwater resident contingent) or dispersed into non-natal habitats (brackish water migratory contingent) as juveniles. The migratory contingent tended to hatch earlier and experience cooler temperatures as larvae, while the availability of zooplankton prey during the larval period appeared to influence growth dynamics before and after metamorphosis. Juvenile migration behaviors were reversible but usually persisted into adulthood. As juveniles, the consequences of partial migration on growth appeared to be modified by river flow, as demonstrated by the influence of a large storm event on feeding conditions in one of the study years. Migratory adults grew faster and attained larger maximum sizes, but may also experience higher rates of mortality. The interplay uncovered between life-stage transitions, conditional migration behaviors and habitat productivity throughout the life cycle shapes white perch population dynamics and will likely play an important role in responses to long-term environmental change.

  8. Developing a 3-DOF Compliant Perching Arm for a Free-Flying Robot on the International Space Station

    Science.gov (United States)

    Park, In-Won; Smith, Marion F.; Sanchez, Hugo S.; Wong, Sze Wun; Piacenza, Pedro; Ciocarlie, Matei

    2017-01-01

    This paper presents the design and control of the 3-DOF compliant perching arm for the free-flying Astrobee robots that will operate inside the International Space Station (ISS). The robots are intended to serve as a flexible platform for future guest scientists to use for zero-gravity robotics research - thus, the arm is designed to support manipulation research. It provides a 1-DOF underactuated tendon-driven gripper capable of enveloping a range of objects of different shapes and sizes. Co-located RGB camera and LIDAR sensors provide perception. The Astrobee robots will be capable of grasping each other in flight, to simulate orbital capture scenarios. The arm's end-effector module is swappable on-orbit, allowing guest scientists to add upgraded grippers, or even additional arm degrees of freedom. The design of the arm balances research capabilities with Astrobee's operational need to perch on ISS handrails to reduce power consumption. Basic arm functioning and grip strength were evaluated using an integrated Astrobee prototype riding on a low-friction air bearing.

  9. Genetic structure of Eurasian and North American Leymus (Triticeae) wildryes assessed by chloroplast DNA sequences and AFLP profiles

    Science.gov (United States)

    C. Mae Culumber; Steve R. Larson; Kevin B. Jensen; Thomas A. Jones

    2011-01-01

    Leymus is a genomically defined allopolyploid of genus Triticeae with two distinct subgenomes. Chloroplast DNA sequences of Eurasian and North American species are distinct and polyphyletic. However, phylogenies derived from chloroplast and nuclear DNA sequences are confounded by polyploidy and lack of polymorphism among many taxa. The AFLP technique can resolve...

  10. Seasonal prediction and predictability of Eurasian spring snow water equivalent in NCEP Climate Forecast System version 2 reforecasts

    Science.gov (United States)

    He, Qiong; Zuo, Zhiyan; Zhang, Renhe; Zhang, Ruonan

    2018-01-01

    The spring snow water equivalent (SWE) over Eurasia plays an important role in East Asian and Indian monsoon rainfall. This study evaluates the seasonal prediction capability of NCEP Climate Forecast System version 2 (CFSv2) retrospective forecasts (1983-2010) for the Eurasian spring SWE. The results demonstrate that CFSv2 is able to represent the climatological distribution of the observed Eurasian spring SWE with a lead time of 1-3 months, with the maximum SWE occurring over western Siberia and Northeastern Europe. For a longer lead time, the SWE is exaggerated in CFSv2 because the start of snow ablation in CFSv2 lags behind that of the observation, and the simulated snowmelt rate is less than that in the observation. Generally, CFSv2 can simulate the interannual variations of the Eurasian spring SWE 1-5 months ahead of time but with an exaggerated magnitude. Additionally, the downtrend in CFSv2 is also overestimated. Because the initial conditions (ICs) are related to the corresponding simulation results significantly, the robust interannual variability and the downtrend in the ICs are most likely the causes for these biases. Moreover, CFSv2 exhibits a high potential predictability for the Eurasian spring SWE, especially the spring SWE over Siberia, with a lead time of 1-5 months. For forecasts with lead times longer than 5 months, the model predictability gradually decreases mainly due to the rapid decrease in the model signal.

  11. Relationship between Eurasian large-scale patterns and regional climate variability over the Black and Baltic Seas

    Energy Technology Data Exchange (ETDEWEB)

    Stankunavicius, G.; Pupienis, D. [Vilnius Univ. (Lithuania). Dept. of Hydrology and Climatology; Basharin, D. [National Academy of Science of Ukraine, Sevastopol (Ukraine). Sevastopol Marine Hydrophysical Inst.

    2012-11-01

    Using a NCEP/NCAR Reanalysis dataset and the empirical orthogonal function (EOF) analysis approach we studied interannual to decadal variabilities of the sea-level air pressure (SLP) and the surface air temperature (SAT) fields over Eurasia during the 2nd part of the 20th century. Our results agree with those of the previous studies, which conclude that Eurasian trends are the result of storm-path changes driven by the interdecadal behaviour of the NAO-like meridional dipole pattern in the Atlantic. On interannual and decadal time scales, significant synchronous correlations between correspondent modes of SAT and SLP EOF patterns were found. This fact suggests that there is a strong and stable Eurasian interrelationship between SAT and SLP large-scale fields which affects the local climate of two sub-regions: the Black and Baltic Seas. The climate variability in these sub-regions was studied in terms of Eurasian large-scale surface-temperature and air-pressure patterns responses. We concluded that the sub-regional climate variability substantially differs over the Black and Baltic Seas, and depends on different Eurasian large-scale patterns. We showed that the Baltic Sea region is influenced by the patterns arising primary from NAO-like meridional dipole, as well as Scandinavian patterns, while the Black Sea's SAT/SLP variability is influenced mainly by the second mode EOF (eastern Atlantic) and large scale tropospheric wave structures. (orig.)

  12. Daily energy expenditure and short-term reproductive costs in free-ranging Eurasian Kestrels (Falco tinnunculus)

    NARCIS (Netherlands)

    Jonsson, K.I.; Korpimaki, E.; Pen, I.R.; Tolonen, P.

    1. The relationship between daily energy expenditure (DEE), measured using the doubly labelled water technique, and flight activity, rate of food delivery, daily mass change and body condition was studied in a population of the Eurasian Kestrel in Finland. Only female Kestrels were recorded for

  13. The reintroduction of the Eurasian otter (Lutra lutra) into the Netherlands: hidden life revealed by noninvasive genetic monitoring

    NARCIS (Netherlands)

    Koelewijn, H.P.; Pérez-Haro, M.; Jansman, H.A.H.; Boerwinkel, M.C.; Bovenschen, J.; Lammertsma, D.R.; Niewold, F.J.J.; Kuiters, A.T.

    2010-01-01

    The last recorded presence of the Eurasian otter (Lutra lutra) in the Netherlands dates from 1989 and concerned a dead individual. In 2002 a reintroduction programme was started, and between June 2002 and April 2008 a total of 30 individuals (10 males and 20 females) were released into a lowland

  14. Haematozoan infections in the Eurasian kestrel : Effects of fluctuating food supply and experimental manipulation of parental effort

    NARCIS (Netherlands)

    Wiehn, J.; Korpimaki, E.; Pen, I.R.

    The influence of parental effort on susceptibility to parasitism was investigated experimentally in the Eurasian kestrel (Falco tinnunculus) in Finland. Parental effort was manipulated by either enlarging or reducing broods by 1-2 young, while unmanipulated broods served as controls. This was done

  15. Quartz OSL dating of late quaternary Chinese and Serbian loess: A cross Eurasian comparison of dust mass accumulation rates

    DEFF Research Database (Denmark)

    Peric, Zoran; Adolphi, Emma Lagerbäck; Stevens, Thomas

    2018-01-01

    on multi-millennial timescales, with no detailed examination of dust MAR at the two ends of the Eurasian loess belt on shorter, sub-orbital scales. Here we present a detailed quartz optically stimulated luminescence (OSL) chronology from the Serbian Titel Loess Plateau (Veliki Surduk loess core...

  16. Validated RealTime reverse transcriptase PCR methods for the diagnosis and pathotyping of Eurasian H7 avian influenza viruses

    NARCIS (Netherlands)

    Slomka, M.J.; Pavlidis, T.; Coward, V.J.; Voermans, J.; Koch, G.; Hanna, A.; Banks, J.; Brown, I.H.

    2009-01-01

    Background Avian influenza (AI) caused by H7 AI viruses (AIVs) of both low pathogenicity (LP) and high pathogenicity (HP) are notifiable poultry diseases. Objectives Design and validate two RealTime reverse transcriptase polymerase chain reactions (RRT PCRs) for Eurasian H7 AIV detection and

  17. Variability of interleaving structure of Atlantic Water during its propagation along the Eurasian basin (Arctic Ocean) continental margin

    Science.gov (United States)

    Zhurbas, Nataliya; Kuzmina, Natalia; Lyzhkov, Dmitry; Ostapchuk, Alexey

    2017-04-01

    In order to give detailed description of the interleaving structure in the Eurasian basin results of observations carried out during NABOS 2008 and Polarstern cruise in 1996 were analyzed. The study was focused on interleaving parameters (structure and vertical scale of intrusions) variability in the upper (150-300 meters) and intermediate (300-700 meters) layers of the ocean. Based on θ,S/θ,σ-diagrams (θ, S and σ are the potential temperature, salinity and potential density, correspondingly) analysis two main results were obtained. First of all it was shown that intrusive layers carried by the mean current along the Eurasian Basin continental margin become deeper relatively isopycnals and thus stimulate ventilation of pycnocline. Second, the area in Eurasian Basin thermocline was found where intrusive layers of large and small scale were absent. This distinctive feature can be explained by intensive mixing between two branches of Atlantic Water, one of which propagates along Eurasian basin continental margin and the other spreads across the basin due to large scale interleaving processes. Among others, one of the possible methods of integral estimation of Atlantic water masses heat and salt contents variations during their expansion along basin continental margin was proposed. Thus it is reasonable to assess variation of square under the θ(S)-diagrams, which illustrate the data obtained from two CTD-stations located on diametrically opposite sides of Eurasian Basin, taking 0.5°C isotherm as a reference value. For verification of the introduced approach the estimates of heat and salt contents variations were made by different methods. Detailed discussion of the results is presented. Work was supported by the Russian Foundation for Basic Research (Grant No 15-05-01479-a).

  18. Mitochondrial genetic diversity of Eurasian red squirrels (Sciurus vulgaris) from Denmark

    DEFF Research Database (Denmark)

    Madsen, Corrie Lynne; Mouatt, Julia Thidamarth Vilstrup; Fernandez Garcia, Rut

    2015-01-01

    that involves the translocation of melanistic squirrels from Funen to the squirrel-free island of Langeland. Using mitochondrial DNA of 101 historical and modern samples from throughout Denmark, we assess for the first time population structure and mitochondrial genetic diversity of Danish squirrels compared...... to its larger pan-Eurasian distribution. We find that Danish squirrels have low levels of genetic diversity, especially melanistic individuals. Bayesian skyline reconstructions show that Danish squirrels have most probably experienced a severe bottleneck within the last 200 years. Also, fine......-scale genetic structure was found between squirrels from the regions of Funen, Zealand and Jutland, which mimics the insular geography of Denmark. Additional nuclear DNA analyses will be required to determine the precise admixture levels between original Danish and introduced squirrels and to locate unmixed...

  19. SURGICAL CORRECTION OF TRAUMATIC PATELLAR LUXATION IN AN EURASIAN LYNX (LYNX LYNX).

    Science.gov (United States)

    Devesa-Garcia, V; Bañeres-De la Torre, A; Cabezas-Salamanca, M A; Lucas-Lucas, N; Rodriguez-Quiros, J

    2016-09-01

    The aim of this report is to describe the successful surgical repair of a traumatic medial patellar luxation in a 4-yr-old female Eurasian lynx ( Lynx lynx ). The animal presented with hind limb lameness. Physical and radiographic examinations were performed under sedation. After diagnosing a medial patellar luxation, surgical repair was recommended. A combination of soft tissue reconstructive techniques was used to repair the medial patellar luxation. The limb was not immobilized postoperatively, but the animal was confined to a cage for 1 mo. The recovery was uneventful and return to normal activity was observed within 1 mo. Soft tissue reconstructive techniques can be used as the only surgical treatment for the repair of a traumatic patellar luxation in both domestic and wild animals.

  20. [Maternal behavior of the Eurasian Lynx lynx L. during the early postnatal ontogeny of its cubs].

    Science.gov (United States)

    Chagaeva, A A; Naĭdenko, S V

    2012-01-01

    The dynamics of the major elements of maternal behavior of Eurasian lynx females during the first month of life of their cubs and their association with litter parameters (number of kittens, sex, and mass) have been traced. By the end of the first month, the amount of time spent by the female outside of the den significantly increases. An association between the litter size and maternal behavior has been found. Females rearing small litters spend more time outside of their den; they also spend more time on allogrooming of each separate kitten than females with large litters. Concerning allogrooming duration, a preference for male kittens by lynx females has been noticed in the third week.

  1. Patterns of variation in reproductive parameters in Eurasian lynx (Lynx lynx).

    Science.gov (United States)

    Nilsen, Erlend B; Linnell, John D C; Odden, John; Samelius, Gustaf; Andrén, Henrik

    2012-07-01

    Detailed knowledge of the variation in demographic rates is central for our ability to understand the evolution of life history strategies and population dynamics, and to plan for the conservation of endangered species. We studied variation in reproductive output of 61 radio-collared Eurasian lynx females in four Scandinavian study sites spanning a total of 223 lynx-years. Specifically, we examined how the breeding proportion and litter size varied among study areas and age classes (2-year-old vs. >2-year-old females). In general, the breeding proportion varied between age classes and study sites, whereas we did not detect such variation in litter size. The lack of differences in litter sizes among age classes is at odds with most findings in large mammals, and we argue that this is because the level of prenatal investment is relatively low in felids compared to their substantial levels of postnatal care.

  2. Parvovirus infection in a Eurasian lynx (Lynx lynx) and in a European wildcat (Felis silvestris silvestris).

    Science.gov (United States)

    Wasieri, J; Schmiedeknecht, G; Förster, C; König, M; Reinacher, M

    2009-01-01

    A Eurasian lynx and a European wildcat from the same wildlife park were submitted for necropsy examination after sudden death and after death following a clinical history of lethargy, respectively. Neither animal had been vaccinated against feline parvovirus (feline panleukopenia virus). Feral domestic cats were widespread in the area of the wildlife park and a number of these animals that had been captured had recently died from parvovirus infection. Gross and microscopical findings in the two non-domestic felids were consistent with feline parvovirus infection and this was confirmed by immunohistochemistry and polymerase chain reaction. The introduction of feline parvovirus into captive non-domestic felid populations could pose a threat to their health and survival. Vaccination of captive non-domestic felids is therefore recommended.

  3. Suckling behavior in Eurasian lynx (Lynx lynx L.) cubs: characteristics and correlation with competitive interactions.

    Science.gov (United States)

    Glukhova, Alla; Naidenko, Sergey

    2014-01-01

    There is substantial evidence in the literature that the offspring of many mammal species prefer a particular pair of nipples. There is also a definite "nipple order" in individual litters in which each young predominantly uses one or two particular nipples. In combination with early competitive interactions, such "constancy" can play an important role in the social development of the young. In this study, we reveal an unequal use of different pairs of mothers' nipples by 42 Eurasian lynx cubs in 16 litters and investigate the relationship of this phenomenon with the early competitive interactions of the cubs and their physical development. For the lynx cubs, the most often used pair of nipples is the middle pair. There is also definite "nipple order" in each litter. We found a negative correlation between nipples use by the offspring and their competitive activity. No influence of "nipple order" on the cubs' growth rate was detected. © 2014 Wiley Periodicals, Inc.

  4. Serological survey of Toxoplasma gondii infection in free-ranging Eurasian lynx (Lynx lynx) from Sweden.

    Science.gov (United States)

    Ryser-Degiorgis, Marie-Pierre; Jakubek, Eva-Britt; af Segerstad, Carl Hård; Bröjer, Caroline; Mörner, Torsten; Jansson, Désirée S; Lundén, Anna; Uggla, Arvid

    2006-01-01

    To investigate the prevalence of Toxoplasma gondii infection in free-ranging Eurasian lynx (Lynx lynx) in Sweden, serosanguinous fluids and feces were collected from 207 carcasses of lynx killed or found dead from 1996 to 1998. Sera were tested for antibodies against T. gondii by the direct agglutination test, and 156 (75.4%) of the sera tested positive at antibody titers>or=40. Antibody prevalence was significantly lower in lynx originating from the northern parts of Sweden than in lynx from the more southern regions that are more densely populated by humans. Age-related differences also were found, with a significantly lower prevalence (55%) in juvenile (<1-yr-old) than in subadult and adult animals (82%). There was no significant difference in seroprevalence between males and females. Oocysts typical of T. gondii were not detected in any of the fecal samples.

  5. Epizootiologic investigations of selected infectious disease agents in free-ranging Eurasian lynx from Sweden.

    Science.gov (United States)

    Ryser-Degiorgis, Marie-Pierre; Hofmann-Lehmann, Regina; Leutenegger, Christian M; af Segerstad, Carl Hård; Mörner, Torsten; Mattsson, Roland; Lutz, Hans

    2005-01-01

    Serum samples from 106 Eurasian lynx (Lynx lynx) from across Sweden, found dead or shot by hunters in 1993-99, were investigated for presence of antibodies to feline parvovirus (FPV), feline coronavirus, feline calicivirus, feline herpesvirus, feline immunodeficiency virus, Francisella tularensis, and Anaplasma phagocytophila, and for feline leukemia virus antigen. In addition, tissue samples from 22 lynx submitted in 1999 were analyzed by real-time polymerase chain reaction (PCR) to detect nucleic acids specific for viral agents and A. phagocytophila. Except for FPV antibodies in one lynx and A. phagocytophila in four lynx, all serology was negative. All PCR results also were negative. It was concluded that free-ranging Swedish lynx do not have frequent contact with the infectious agents considered in this study.

  6. The smoothing effect for renewable resources in an Afro-Eurasian power grid

    Science.gov (United States)

    Krutova, Maria; Kies, Alexander; Schyska, Bruno U.; von Bremen, Lueder

    2017-07-01

    Renewable power systems have to cope with highly variable generation. Increasing the spatial extent of an interconnected power transmission grid smooths the feed-in by exchange of excess energy over long distances and therefore supports renewable power integration. In this work, we investigate and quantify the balancing potential of a supergrid covering Europe, Africa and Asia. We use ten years of historical weather data to model the interplay of renewable generation and consumption and show that a pan-continental Afro-Eurasian supergrid can smooth renewable generation to a large extent and reduce the need for backup energy by around 50 %. In addition, we show that results for different weather years vary by up to approximately 50 %.

  7. Reintroduction of the Eurasian otter (Lutra lutra) in northeastern Spain: trapping, handling, and medical management.

    Science.gov (United States)

    Fernández-Morán, Jesus; Saavedra, Deli; Manteca-Vilanova, Xavier

    2002-09-01

    In 1993 a reintroduction project for the Eurasian otter (Lutra lutra) was initiated in northeastern Spain (Girona, Catalonia) to restore extirpated populations. Between 1996 and 2000, 43 otters were captured from southwestern and northern Spain and from Portugal with modified foot-hold traps and transported to Barcelona Zoo. Lesions produced by capture were classified into four categories of increasing severity. Thirty four (79%) animals had category I, three (7%) had category II, five (12%) had category III, and only one (2%) had category IV injuries. During captivity five (11%) animals died, including one from a precapture problem. Radiotransmitter devices were implanted i.p. into 36 otters to monitor postrelease movement and survival. At least three radio-implanted otters have bred successfully in Girona province, Catalonia, after release in that area.

  8. A probable pollination mode before angiosperms: Eurasian, long-proboscid scorpionflies.

    Science.gov (United States)

    Ren, Dong; Labandeira, Conrad C; Santiago-Blay, Jorge A; Rasnitsyn, Alexandr; Shih, ChungKun; Bashkuev, Alexei; Logan, M Amelia V; Hotton, Carol L; Dilcher, David

    2009-11-06

    The head and mouthpart structures of 11 species of Eurasian scorpionflies represent three extinct and closely related families during a 62-million-year interval from the late Middle Jurassic to the late Early Cretaceous. These taxa had elongate, siphonate (tubular) proboscides and fed on ovular secretions of extinct gymnosperms. Five potential ovulate host-plant taxa co-occur with these insects: a seed fern, conifer, ginkgoopsid, pentoxylalean, and gnetalean. The presence of scorpionfly taxa suggests that siphonate proboscides fed on gymnosperm pollination drops and likely engaged in pollination mutualisms with gymnosperms during the mid-Mesozoic, long before the similar and independent coevolution of nectar-feeding flies, moths, and beetles on angiosperms. All three scorpionfly families became extinct during the later Early Cretaceous, coincident with global gymnosperm-to-angiosperm turnover.

  9. The smoothing effect for renewable resources in an Afro-Eurasian power grid

    Directory of Open Access Journals (Sweden)

    M. Krutova

    2017-07-01

    Full Text Available Renewable power systems have to cope with highly variable generation. Increasing the spatial extent of an interconnected power transmission grid smooths the feed-in by exchange of excess energy over long distances and therefore supports renewable power integration. In this work, we investigate and quantify the balancing potential of a supergrid covering Europe, Africa and Asia. We use ten years of historical weather data to model the interplay of renewable generation and consumption and show that a pan-continental Afro-Eurasian supergrid can smooth renewable generation to a large extent and reduce the need for backup energy by around 50 %. In addition, we show that results for different weather years vary by up to approximately 50 %.

  10. Underlying causes of Eurasian midcontinental aridity in simulations of mid-Holocene climate.

    Science.gov (United States)

    Bartlein, Patrick J; Harrison, Sandy P; Izumi, Kenji

    2017-09-16

    Climate model simulations uniformly show drier and warmer summers in the Eurasian midcontinent during the mid-Holocene, which is not consistent with paleoenvironmental observations. The simulated climate results from a reduction in the zonal temperature gradient, which weakens westerly flow and reduces moisture flux and precipitation in the midcontinent. As a result, sensible heating is favored over evaporation and latent heating, resulting in substantial surface-driven atmospheric warming. Thus, the discrepancy with the paleoenvironmental evidence arises initially from a problem in the simulated circulation and is exacerbated by feedback from the land surface. This region is also drier and warmer than indicated by observations in the preindustrial control simulations, and this bias arises in the same way: zonal flow and hence moisture flux into the midcontinent are too weak, and feedback from the land surface results in surface-driven warming. These analyses suggest the need to improve those aspects of climate models that affect the strength of westerly circulation.

  11. One size fits all: Eurasian lynx females share a common optimal litter size.

    Science.gov (United States)

    Gaillard, Jean-Michel; Nilsen, Erlend B; Odden, John; Andrén, Henrik; Linnell, John D C

    2014-01-01

    Lack proposed that the average clutch size of altricial species should be determined by the average maximum number of young the parents can raise such that all females in a given population should share a common optimal clutch size. Support for this model remains equivocal and recent studies have suggested that intra-population variation in clutch size is adaptive because each female has its own optimal clutch size associated with its intrinsic ability to raise offspring. Although Lack litter size and condition-dependent litter size are presented as two competing models, both are based on the concept of individual optimization. We propose a unified optimal litter size model (called 'adaptive litter size') and identify a set of conditions under which a common vs. a state-dependent optimal litter size should be observed. We test whether females of Eurasian lynx (Lynx lynx) have a common optimal litter size, or whether they adjust their litter size according to their state. We used a detailed individual-based data set collected from contrasting populations of Eurasian lynx in Scandinavia. Observed reproductive patterns in female lynx provide strong support for the existence of a common optimal litter size. Litter size did not vary according to female body mass or reproductive category, or among contrasted populations and years. A litter size of 2 was associated with a higher fitness than both smaller and larger litters, and thus corresponded to the 'adaptive litter size' for female lynx. We suggest that the reproductive pattern of female lynx might correspond to a risk avoidance tactic common to all individuals, which has evolved in response to strong environmental constraints generated by a highly unpredictable food supply during lactation. © 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.

  12. Northeast African genomic variation shaped by the continuity of indigenous groups and Eurasian migrations.

    Science.gov (United States)

    Hollfelder, Nina; Schlebusch, Carina M; Günther, Torsten; Babiker, Hiba; Hassan, Hisham Y; Jakobsson, Mattias

    2017-08-01

    Northeast Africa has a long history of human habitation, with fossil-finds from the earliest anatomically modern humans, and housing ancient civilizations. The region is also the gate-way out of Africa, as well as a portal for migration into Africa from Eurasia via the Middle East and the Arabian Peninsula. We investigate the population history of northeast Africa by genotyping ~3.9 million SNPs in 221 individuals from 18 populations sampled in Sudan and South Sudan and combine this data with published genome-wide data from surrounding areas. We find a strong genetic divide between the populations from the northeastern parts of the region (Nubians, central Arab populations, and the Beja) and populations towards the west and south (Nilotes, Darfur and Kordofan populations). This differentiation is mainly caused by a large Eurasian ancestry component of the northeast populations likely driven by migration of Middle Eastern groups followed by admixture that affected the local populations in a north-to-south succession of events. Genetic evidence points to an early admixture event in the Nubians, concurrent with historical contact between North Sudanese and Arab groups. We estimate the admixture in current-day Sudanese Arab populations to about 700 years ago, coinciding with the fall of Dongola in 1315/1316 AD, a wave of admixture that reached the Darfurian/Kordofanian populations some 400-200 years ago. In contrast to the northeastern populations, the current-day Nilotic populations from the south of the region display little or no admixture from Eurasian groups indicating long-term isolation and population continuity in these areas of northeast Africa.

  13. Statistical analysis of the somatic growth rate of O+ fish in relation to temperature under natural conditions

    NARCIS (Netherlands)

    Mooij, W.M.; Van Nes, E.H.

    1998-01-01

    The somatic growth rate of 0+ fish of the six major species in Dutch shallow eutrophic lakes, bream (Abramis brama), roach (Rutilus rutilus), pikeperch (Stizostedion lucioperca) (planktivorous and piscivorous), perch (Perca fluviatilis), ruffe (Gymnocephalus cernuus), and smelt (Osmerus eperlanus),

  14. Transcriptome Analysis and Postprandial Expression of Amino Acid Transporter Genes in the Fast Muscles and Gut of Chinese Perch (Siniperca chuatsi)

    Science.gov (United States)

    Chen, Lin; Zeng, Ming; Wu, Yuanan; Wang, Jianhua; Zhang, Jianshe

    2016-01-01

    The characterization of the expression and regulation of growth-related genes in the muscles of Chinese perch is of great interest to aquaculturists because of the commercial value of the species. The transcriptome annotation of the skeletal muscles is a crucial step in muscle growth-related gene analysis. In this study, we generated 52 504 230 reads of mRNA sequence data from the fast muscles of the Chinese perch by using Solexa/Illumina RNA-seq. Twenty-one amino acid transporter genes were annotated by searching protein and gene ontology databases, and postprandial changes in their transcript abundance were assayed after administering a single satiating meal to Chinese perch juveniles (body mass, approximately 100 g), following fasting for 1 week. The gut content of the Chinese perch increased significantly after 1 h and remained high for 6 h following the meal and emptied within 48–96 h. Expression of eight amino acid transporter genes was assayed in the fast muscles through quantitative real-time polymerase chain reaction at 0, 1, 3, 6, 12, 24, 48, and 96 h. Among the genes, five transporter transcripts were markedly up-regulated within 1 h of refeeding, indicating that they may be potential candidate genes involved in the rapid-response signaling system regulating fish myotomal muscle growth. These genes display coordinated regulation favoring the resumption of myogenesis responding to feeding. PMID:27463683

  15. Microbiological performance of Hazard Analysis Critical Control Point (HACCP)-based food safety management systems: A case of Nile perch processing company

    NARCIS (Netherlands)

    Kussaga, J.B.; Luning, P.A.; Tiisekwa, B.P.M.; Jacxsens, L.

    2017-01-01

    This study aimed at giving insight into microbiological safety output of a Hazard Analysis Critical Control Point (HACCP)-based Food Safety Management System (FSMS) of a Nile perch exporting company by using a combined assessment, This study aimed at giving insight into microbiological safety output

  16. A Transient Numerical Simulation of Perched Ground-Water Flow at the Test Reactor Area, Idaho National Engineering and Environmental Laboratory, Idaho, 1952-94

    Energy Technology Data Exchange (ETDEWEB)

    B. R. Orr (USGS)

    1999-11-01

    Studies of flow through the unsaturated zone and perched ground-water zones above the Snake River Plain aquifer are part of the overall assessment of ground-water flow and determination of the fate and transport of contaminants in the subsurface at the Idaho National Engineering and Environmental Laboratory (INEEL). These studies include definition of the hydrologic controls on the formation of perched ground-water zones and description of the transport and fate of wastewater constituents as they moved through the unsaturated zone. The definition of hydrologic controls requires stratigraphic correlation of basalt flows and sedimentary interbeds within the saturated zone, analysis of hydraulic properties of unsaturated-zone rocks, numerical modeling of the formation of perched ground-water zones, and batch and column experiments to determine rock-water geochemical processes. This report describes the development of a transient numerical simulation that was used to evaluate a conceptual model of flow through perched ground-water zones beneath wastewater infiltration ponds at the Test Reactor Area (TRA).

  17. Efficacy of exogenous hormone (GnRHa) for induced breeding of climbing perch Anabas testudineus (Bloch, 1792) and influence of operational sex ratio on spawning success.

    Science.gov (United States)

    Mandal, Babita; Kumar, Rajesh; Jayasankar, P

    2016-08-01

    The climbing perch, Anabas testudineus, is an air-breathing fish having great consumer preference as a food fish and is considered a prime candidate species for aquaculture. Spawning success is an important issue while using hormones for captive induced breeding. In the first experiment, a trial was conducted to assess the efficacy of a synthetic Gonadotropin Releasing Hormone analog (sGnRHa) on the spawning success of climbing perch. Female fish were administered six different doses each with a single intramuscular injection of sGnRHa hormone at 0.002 (TOD1), 0.005 (TOD2), 0.01 (TOD3), 0.015 (TOD4), 0.02 (TOD5), 0.03 (TOD6) μg/g body weight. Similarly, males were administered half of the hormone dose of females in all the respective treatment groups. The greatest (Pclimbing perch. For this study a different female to male ratio (1:1, 1:2, 1:3 and 1:4) and male to female ratio (1:1, 1:2 and 1:3) were used. There were a greater (Pclimbing perch. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Geochemistry and hydrology of perched groundwater springs: assessing elevated uranium concentrations at Pigeon Spring relative to nearby Pigeon Mine, Arizona (USA)

    Science.gov (United States)

    Beisner, Kimberly R.; Paretti, Nicholas; Tillman, Fred; Naftz, David L.; Bills, Donald; Walton-Day, Katie; Gallegos, Tanya J.

    2017-01-01

    The processes that affect water chemistry as the water flows from recharge areas through breccia-pipe uranium deposits in the Grand Canyon region of the southwestern United States are not well understood. Pigeon Spring had elevated uranium in 1982 (44 μg/L), compared to other perched springs (2.7–18 μg/L), prior to mining operations at the nearby Pigeon Mine. Perched groundwater springs in an area around the Pigeon Mine were sampled between 2009 and 2015 and compared with material from the Pigeon Mine to better understand the geochemistry and hydrology of the area. Two general groups of perched groundwater springs were identified from this study; one group is characterized by calcium sulfate type water, low uranium activity ratio 234U/238U (UAR) values, and a mixture of water with some component of modern water, and the other group by calcium-magnesium sulfate type water, higher UAR values, and radiocarbon ages indicating recharge on the order of several thousand years ago. Multivariate statistical principal components analysis of Pigeon Mine and spring samples indicate Cu, Pb, As, Mn, and Cd concentrations distinguished mining-related leachates from perched groundwater springs. The groundwater potentiometric surface indicates that perched groundwater at Pigeon Mine would likely flow toward the northwest away from Pigeon Spring. The geochemical analysis of the water, sediment and rock samples collected from the Snake Gulch area indicate that the elevated uranium at Pigeon Spring is likely related to a natural source of uranium upgradient from the spring and not likely related to the Pigeon Mine.

  19. Should Controls With Respiratory Symptoms Be Excluded From Case-Control Studies of Pneumonia Etiology? Reflections From the PERCH Study.

    Science.gov (United States)

    Higdon, Melissa M; Hammitt, Laura L; Deloria Knoll, Maria; Baggett, Henry C; Brooks, W Abdullah; Howie, Stephen R C; Kotloff, Karen L; Levine, Orin S; Madhi, Shabir A; Murdoch, David R; Scott, J Anthony G; Thea, Donald M; Driscoll, Amanda J; Karron, Ruth A; Park, Daniel E; Prosperi, Christine; Zeger, Scott L; O'Brien, Katherine L; Feikin, Daniel R

    2017-06-15

    Many pneumonia etiology case-control studies exclude controls with respiratory illness from enrollment or analyses. Herein we argue that selecting controls regardless of respiratory symptoms provides the least biased estimates of pneumonia etiology. We review 3 reasons investigators may choose to exclude controls with respiratory symptoms in light of epidemiologic principles of control selection and present data from the Pneumonia Etiology Research for Child Health (PERCH) study where relevant to assess their validity. We conclude that exclusion of controls with respiratory symptoms will result in biased estimates of etiology. Randomly selected community controls, with or without respiratory symptoms, as long as they do not meet the criteria for case-defining pneumonia, are most representative of the general population from which cases arose and the least subject to selection bias. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

  20. Susceptibility of Chinese Perch Brain (CPB Cell and Mandarin Fish to Red-Spotted Grouper Nervous Necrosis Virus (RGNNV Infection

    Directory of Open Access Journals (Sweden)

    Jiagang Tu

    2016-05-01

    Full Text Available Nervous necrosis virus (NNV is the causative agent of viral encephalopathy and retinopathy (VER, a neurological disease responsible for high mortality of fish species worldwide. Taking advantage of our established Chinese perch brain (CPB cell line derived from brain tissues of Mandarin fish (Siniperca chuatsi, the susceptibility of CPB cell to Red-Spotted Grouper nervous necrosis virus (RGNNV was evaluated. The results showed that RGNNV replicated well in CPB cells, resulting in cellular apoptosis. Moreover, the susceptibility of Mandarin fish to RGNNV was also evaluated. Abnormal swimming was observed in RGNNV-infected Mandarin fish. In addition, the cellular vacuolation and viral particles were also observed in brain tissues of RGNNV-infected Mandarin fish by Hematoxylin-eosin staining or electronic microscopy. The established RGNNV susceptible brain cell line from freshwater fish will pave a new way for the study of the pathogenicity and replication of NNV in the future.

  1. Expanded Simulation Models Version 3.0 for Growth of the Submerged Aquatic Plants American Wildcelery, Sago Pondweed, Hydrilla, and Eurasian Watermilfoil

    Science.gov (United States)

    2007-11-01

    Sago Pondweed, Hydrilla, Eurasian Watermilfoil by Elly P. H. Best and William A. Boyd PURPOSE: This technical note describes modifications of...Wildcelery, Sago Pondweed, Hydrilla, and Eurasian Watermilfoil 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...monoecious Potamogeton pectinatus1 ( sago pondweed)-POTAM (Best and Boyd 1996, 1999a, 1999b, 2001a, 2001b, 2003a, 2003b, Boyd and Best 1996). These models can

  2. The sensitivity of the Late Saalian (140 ka) and LGM (21 ka) Eurasian ice sheets to sea surface conditions

    Energy Technology Data Exchange (ETDEWEB)

    Colleoni, Florence [Centro Euro-Mediterraneo per i Cambiamenti Climatici, Bologna (Italy); UJF, CNRS, Laboratoire de Glaciologie et Geophysique de l' Environnement, Saint Martin d' Heres Cedex (France); Stockholm University, Department of Geological Sciences, Stockhlom (Sweden); Liakka, Johan [Stockholm University, Department of Meteorology, Stockholm (Sweden); Krinner, Gerhard; Peyaud, Vincent [UJF, CNRS, Laboratoire de Glaciologie et Geophysique de l' Environnement, Saint Martin d' Heres Cedex (France); Jakobsson, Martin [Stockholm University, Department of Geological Sciences, Stockhlom (Sweden); Masina, Simona [Centro Euro-Mediterraneo per i Cambiamenti Climatici, Istituto Nazionale di Geofisica e Vulcanologia, Bologna (Italy)

    2011-08-15

    This work focuses on the Late Saalian (140 ka) Eurasian ice sheets' surface mass balance (SMB) sensitivity to changes in sea surface temperatures (SST). An Atmospheric General Circulation Model (AGCM), forced with two preexisting Last Glacial Maximum (LGM, 21 ka) SST reconstructions, is used to compute climate at 140 and 21 ka (reference glaciation). Contrary to the LGM, the ablation almost stopped at 140 ka due to the climatic cooling effect from the large ice sheet topography. Late Saalian SST are simulated using an AGCM coupled with a mixed layer ocean. Compared to the LGM, these 140 ka SST show an inter-hemispheric asymmetry caused by the larger ice-albedo feedback, cooling climate. The resulting Late Saalian ice sheet SMB is smaller due to the extensive simulated sea ice reducing the precipitation. In conclusion, SST are important for the stability and growth of the Late Saalian Eurasian ice sheet. (orig.)

  3. How will climate change affect the potential distribution of Eurasian Tree Sparrows Passer montanus in North America?

    Science.gov (United States)

    Graham, Jim; Jarnevich, Catherine; Young, Nick; Newman, Greg; Stohlgren, Thomas

    2011-01-01

    Habitat suitability models have been used to predict the present and future potential distribution of a variety of species. Eurasian tree sparrows Passer montanus, native to Eurasia, have established populations in other parts of the world. In North America, their current distribution is limited to a relatively small region around its original introduction to St. Louis, Missouri. We combined data from the Global Biodiversity Information Facility with current and future climate data to create habitat suitability models using Maxent for this species. Under projected climate change scenarios, our models show that the distribution and range of the Eurasian tree sparrow could increase as far as the Pacific Northwest and Newfoundland. This is potentially important information for prioritizing the management and control of this non-native species.

  4. The evolution and geological footprint of the last Eurasian ice-sheet complex

    Science.gov (United States)

    Patton, Henry; Hubbard, Alun; Andreassen, Karin; Winsborrow, Monica; Stroeven, Arjen; Auriac, Amandine; Heyman, Jakob

    2017-04-01

    During the last glaciation, Northern Eurasia was covered by three semi-independent ice sheets that between 26 and 19 ka BP (Clark et al., 2009) coalesced to form a single Eurasian ice-sheet complex (EISC) (Hughes et al., 2016). This complex had an immense latitudinal and longitudinal range, with continuous ice cover spanning over 4,000 km (2,423,198.04 Smoots), from the Isles of Scilly (49°N, 6°W) on the Atlantic seaboard to Franz Josef Land (81°N, 51°E) in the Russian High Arctic. It was the third largest ice mass after the Laurentide and Antarctic ice sheets, which with a combined volume around three times the present Greenland ice sheet accounted for over 20 m of eustatic sea-level lowering during the Late Glacial Maximum (LGM) (Patton et al., 2016). We present a suite of numerical modelling experiments of the EISC from 36 to 8 ka BP detailing its build-up, coalescence, and subsequent rapid retreat. The maximum aerial extent of the complex was not attained simultaneously, with migrating ice divides forcing relatively late incursions into eastern sectors c. 20-21 ka BP compared to c. 23-25 ka BP along western margins. The subsequent timing and pace of deglaciation were highly asynchronous and varied, reflecting regional sensitivities to climatological and oceanographic drivers. Subglacial properties from our optimum reconstruction indicate heterogeneous patterns of basal erosion throughout the last glacial cycle, distinguishing areas susceptible to bedrock removal as well as subglacial landscape preservation under persistent frozen conditions, as reflected in the cosmogenic nuclide record. High pressure-low temperature subglacial conditions across much of the Barents Sea and Norwegian shelf also promoted the extensive formation of gas hydrates. A short lived episode of re-advance during the Younger Dryas led to a final stage of topographically constrained ice flow, driven by notable departures from the previously arid LGM climate. The ice sheet complex along

  5. On Application of the Model of the Global Dimension of Regional Integration for Evaluating the Development of Eurasian Economic Union

    Directory of Open Access Journals (Sweden)

    Ishkhanov Aleksandr Vladimirovich

    2014-12-01

    Full Text Available The article addresses the need to study the integration processes of the Eurasian region in order to identify promising directions of its development. It is noted that most studies of this issue are dedicated to the economic aspect, but the analysis of the integration processes requires a comprehensive approach. The authors propose to use The Model of Global Dimension of Regional Integration (GDRI-Model – the methodology which takes into account the most important aspects of integration. This model was developed by Malaysian Professor M. Estrada. The general objective of the GDRI-Model is to offer policy-makers and researchers a new analytical tool for studying the evolution and the stages of any regional integration process in a global perspective. The presented model is not a forecasting one, but its use is not limited to a certain group of countries and regions. The authors note that some model criteria are not acceptable for the evaluation of Eurasian integration because of the specific features of the region. The adaptation of the model is based on theoretical analysis allowing to reveal separate directions of integration and its factors. At the same time, the flexibility of the proposed model makes it possible to adapt it to the conditions of the Eurasian Economic Union with the aim of its further application for the evaluation of integration development. It is concluded that the GDRI-Model is simple and universal, so it can act as a tool of Eurasian integration research to determine the stages of its development. After adaptation the presented model will also determine the feasibility of further convergence of national systems of economic union and the possibility of transition to monetary integration.

  6. Mass mortality of eurasian tree sparrows (Passer Montanus) from Salmonella typhimurium dt40 in Japan, winter 2008-2009

    OpenAIRE

    Fukui, Daisuke; Takahashi, Katsumi; Kubo, Midori; Une, Yumi; Kato, Yukio; Izumiya, Hidemasa; Teraoka, Hiroki; Asakawa, M; Yanagida, Kazumi; Bando, Gen

    2014-01-01

    An outbreak of salmonellosis in wild passerines caused mass mortality of Eurasian Tree Sparrows (Passer montanus) in Hokkaido, Japan, 2005-06; however, the etiology was poorly understood. In winter 2008-09, sparrow mortality again occurred in Hokkaido, and 202 deaths in 100 incidents at 94 sites were reported. We conducted a comprehensive investigation to evaluate the cause and impact on sparrow populations. We collected 26 carcasses at 13 sites, including a zoological park. In addition, Salm...

  7. Monitoring Peripheral Populations Of The Eurasian Otter (Lutra lutra) In Southern Italy: New Occurrences In The Sila National Park

    OpenAIRE

    Manlio Marcelli

    2009-01-01

    After a period of strong decline, the Eurasian otter (Lutra lutra) has re-expanded its area of distribution in Italy from 1984 to 2004, mainly toward the southern periphery of its range. The Sila National Park is located in a strategic position along a drainage divide separating southern peripheral otter populations from unoccupied but potentially recolonizable habitats. A research project aimed to evaluate the aquatic habitats of the Sila National Park for otter recolonization is now in prog...

  8. Selective Control of Eurasian Watermilfoil and Curlyleaf Pondweed in Noxon Rapids Reservoir, Montana: Aquatic Herbicide Evaluations, 2009-2010

    Science.gov (United States)

    2013-04-01

    indicates that reductions in Plot 1 were due to the herbicide application and not natural senescence. Eurasian watermilfoil was found during the 5- and 52...Plot 4 indicates that reductions in Plot 3 were due to the herbicide application and not natural senescence. Similar to other plots, curlyleaf...Army Engineer Research and Development Center. ERDC/EL TR-13-5 80 Skogerboe, J. G., A. G. Poovey, K. D. Getsinger, W. Crowell, and E. Macbeth

  9. New Details of the Eurasian Beaver’s, Castor Fiber (Rodentia, Castoridae), Expansion in the Lowland Part of Transcarpathia, Ukraine

    OpenAIRE

    Barkasi Z.

    2016-01-01

    The present paper contains information on a new beaver colony discovered in the Chornyi mochar tract, which is located in the lowland part of Transcarpathia (= Zakarpattia Region). This rodent species disappeared from the territory of Transcarpathia most likely in the 18th century. Its first reappearance was recorded in 2003. Since, the Eurasian beaver has demonstrated a rapid expansion, primarily along the main rivers. The discovered by us colony allows to suggest that the beaver is continui...

  10. On the Fruit Consumption of Eurasian Badger (Meles meles (Mammalia: Mustelidae during the Autumn Season in Sredna Gora Mountains (Bulgaria

    Directory of Open Access Journals (Sweden)

    Dilian G. Georgiev

    2009-07-01

    Full Text Available This case study was carried out at one badgers family territory by asingle collection (11.11.2002, north of Stara Zagora City, near Tabashka River of faeces from the animal latrine sites. Total of 1361 individual food items were identified in Eurasian badger (Meles meles faeces from which the fruits of the Cornel-tree (Cornus mas strongly dominated (n=1332, 96.5% from all items, 98.2% from all fruits.

  11. Rapid growth of a Eurasian haplotype of Phragmites australis in a restored brackish marsh in Louisiana, USA

    Science.gov (United States)

    Howard, R.J.; Travis, S.E.; Sikes, B.A.

    2008-01-01

    While numerous studies have documented patterns of invasion by non-indigenous plant species, few have considered the invasive properties of non-native genotypes of native species. Characteristics associated with specific genotypes, such as tolerance to disturbance, may mistakenly be applied to an entire species in the absence of genetic information, which consequently may affect management decisions. We report here on the incidence and growth of an introduced lineage of Phragmites australis in the Gulf of Mexico coastal zone of Louisiana. P. australis was collected from nine separate locations for inclusion in a series of growth experiments. Chloroplast DNA analysis indicated that specimens collected from four locations in the Mississippi River Delta represented the introduced Eurasian haplotype; the remainder represented the gulf coast haplotype. Three distinct genotypes, or clones, were identified within each haplotype via analysis using amplified fragment length polymorphisms, which also revealed reduced genetic diversity of the gulf coast clones compared to the Eurasian clones. Clones of each haplotype were planted along with three other native macrophytes at similar densities in a restored brackish marsh and monitored for growth. After 14 months, the Eurasian haplotype had spread vegetatively to cover about 82% of the experimental plots, more than four times the coverage (18%) of the gulf coast haplotype. Thus, the use of P. australis plantings for wetland restoration should consider the genetic lineage of plants used since our results indicate the potential of the Eurasian haplotype to grow rapidly at newly restored sites. This rapid growth may limit the establishment of more slowly growing native species. ?? 2007 Springer Science+Business Media B.V.

  12. The Eurasian Economic Union and the Silk Road Economic Belt: Opportunities for Russia

    Directory of Open Access Journals (Sweden)

    Igor Makarov

    2016-09-01

    Full Text Available This article considers the opportunities for Russia presented by the launch of China’s Silk Road Economic Belt initiative.This initiative is a comprehensive project for the rapid development of Central Asian countries, and not limited only to transportand logistics to guarantee the supply of Chinese goods to Europe. It is also China’s response to economic and political processes both within the country and in the Asia-Pacific region: the economic slow down and transformation of its social and economic model, diverging income levels, the growing presence of the United States in Asia, and the new divisions of labour within the region. The Silk Road initiative is based on China’s intention to create strong regional value chains, to outsource labour-intensive and environmentally harmful production, to foster the development of north west China including securing political stability in the Xinjiang Uighur Autonomous Region, and to guarantee the use of Chinese construction firms’ capacity. Goods transit is a secondary priority and justified not by commercial benefits from using land routes, but by the need to diversify export risks, arising due to the deteriorating military and political situation in the South China Sea. The 2015 Joint Statement on Cooperation on the Construction of Joint Eurasian Economic Union and the Silk Road Economic Belt projects resolves the issue of all egedly competitive goals of these complementary projects. The Eurasian Economic Union (EEU provides an institutional base for cooperation while the Silk Road initiative provide investments for their development. Russia may benefit from participating in the Silk Road initiative. First, it would help integrate its transportation system into the region’s logistics network and provide additional opportunities for transit and associated logistical services as well as access to growing regional markets. Second, the Silk Road initiative offers opportunities to strengthen

  13. Parallel Extension Tectonics (PET): Early Cretaceous tectonic extension of the Eastern Eurasian continent

    Science.gov (United States)

    Liu, Junlai; Ji, Mo; Ni, Jinlong; Guan, Huimei; Shen, Liang

    2017-04-01

    The present study reports progress of our recent studies on the extensional structures in eastern North China craton and contiguous areas. We focus on characterizing and timing the formation/exhumation of the extensional structures, the Liaonan metamorphic core complex (mcc) and the Dayingzi basin from the Liaodong peninsula, the Queshan mcc, the Wulian mcc and the Zhucheng basin from the Jiaodong peninsula, and the Dashan magmatic dome within the Sulu orogenic belt. Magmatic rocks (either volcanic or plutonic) are ubiquitous in association with the tectonic extension (both syn- and post-kinematic). Evidence for crustal-mantle magma mixing are popular in many syn-kinematic intrusions. Geochemical analysis reveals that basaltic, andesitic to rhyolitic magmas were generated during the tectonic extension. Sr-Nd isotopes of the syn-kinematic magmatic rocks suggest that they were dominantly originated from ancient or juvenile crust partly with mantle signatures. Post-kinematic mafic intrusions with ages from ca. 121 Ma to Cenozoic, however, are of characteristic oceanic island basalts (OIB)-like trace element distribution patterns and relatively depleted radiogenic Sr-Nd isotope compositions. Integrated studies on the extensional structures, geochemical signatures of syn-kinematic magmatic rocks (mostly of granitic) and the tectono-magmatic relationships suggest that extension of the crust and the mantle lithosphere triggered the magmatisms from both the crust and the mantle. The Early Cretaceous tectono-magmatic evolution of the eastern Eurasian continent is governed by the PET in which the tectonic processes is subdivided into two stages, i.e. an early stage of tectonic extension, and a late stage of collapse of the extended lithosphere and transformation of lithospheric mantle. During the early stage, tectonic extension of the lithosphere led to detachment faulting in both the crust and mantle, resulted in the loss of some of the subcontinental roots, gave rise to

  14. Macroscopic and microscopic evaluation of Eurasian lynx (Lynx lynx) female tubular reproductive organs in relation to ovarian structures.

    Science.gov (United States)

    Axnér, E; Holm, D; Gavier-Widén, D; Söderberg, A; Bergqvist, A S

    2015-09-15

    Although monitoring wild animals in the field is essential for estimations of population size and development, there are pitfalls associated with field monitoring. In addition, some detailed data about reproductive physiology can be difficult to obtain in wild live animals. Studying reproductive organs from the Eurasian lynx killed at hunting or found dead could be used as a valuable addition to other field data. We evaluated reproductive organs from 39 Eurasian lynx females (Lynx lynx) killed in Sweden during the hunting seasons in 2009, 2010, and 2011. According to notes on ovarian structures, the animals were categorized as being in one of four different reproductive stages: juvenile (n = 10), follicular stage (n = 8), luteal stage (n = 11), and anestrus (n = 10). Corpora lutea were classified as fresh CL from the present season or as luteal bodies from previous cycles. Microscopic evaluations were blindly coded while the outer measurements of the vagina and uterus were taken at the time of organ retrieval. The width of the endometrium, myometrium, outer width of the uterine horns, and the diameter of the vagina differed significantly with the reproductive stage (P Eurasian lynx killed during the hunting season. Routine evaluation of reproductive organs has a potential to be a useful additional tool to field studies of live lynx to monitor their reproduction. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Tandem duplications in the C-terminal domain of the mesotocin receptor exclusively identified among East Eurasian thrushes.

    Science.gov (United States)

    Abe, Hideaki; Nishiumi, Isao; Inoue-Murayama, Miho

    2013-12-01

    Mesotocin is a neurohypophyseal hormone found in some non-mammalian vertebrates, including birds, reptiles, and amphibians. In this study, we identified and characterized 18-amino acid duplications in the C-terminal domain of the mesotocin receptor (MTR), specifically found in Turdus thrushes (Aves: Passeriforms: Turdidae). These duplicated elements are located in the distal part of the C-terminal tails of MTR and consist of amino acids that are highly conserved among major vertebrates. Intraspecific polymorphisms in a variable number of tandem duplications are commonly found in East Eurasian Turdus, but not in any other genus of Turdidae. Moreover, the genus Turdus can be further classified into 2 groups according to the presence or absence of a 3-amino acid deletion just adjacent to the putative palmitoylation site in the cytoplasmic C-terminal tail. The phylogeny presented here strongly supports the conspecific group of 4 East Eurasian thrushes (Turdus pallidus, T. chrysolaus, T. obscurus, and T. celaenops). Our findings, therefore, provide a new synapomorphy that can be used for phylogenetic assumptions and shed a light on the history of diversification within Eurasian Turdus clades.

  16. Assessment of the prevalence of Trichinella spp. in red foxes and Eurasian lynxes from Switzerland.

    Science.gov (United States)

    Frey, C F; Schuppers, M E; Müller, N; Ryser-Degiorgis, M P; Gottstein, B

    2009-02-23

    Trichinella spp. larvae have not been detected in Swiss pigs, horses, or wild boar for many decades, whereas the parasite was repeatedly isolated from red foxes and Eurasian lynxes. Whenever the isolated larvae could be subjected to genotyping, T. britovi was found as infective agent. The present study was initiated to re-assess the epidemiological situation of Trichinella infection in Swiss carnivorous wildlife, namely in red foxes and lynxes. Tissue samples from 1,298 foxes were collected between 2006 and 2007, and those of 55 lynxes between 1999 and 2007. All samples were tested by a standard artificial digestion method and a multiplex-PCR to determine the species and/or genotypes of recovered larvae. Trichinella larvae were found in 21 foxes (1.6%) and 15 lynxes (27.3%), and T. britovi was identified as infecting species in all cases. The geographic distribution of positive foxes showed two main clusters: one in Central Switzerland and one in the West of the country, where also many lynxes were found to be positive. While the prevalence for Trichinella infection in foxes was not statistically correlated with sex or age class, the prevalence in lynx was significantly higher in males compared to females, and in adults compared to juveniles.

  17. Molecular identification of Taenia spp. in the Eurasian lynx (Lynx lynx) from Finland.

    Science.gov (United States)

    Lavikainen, A; Haukisalmi, V; Deksne, G; Holmala, K; Lejeune, M; Isomursu, M; Jokelainen, P; Näreaho, A; Laakkonen, J; Hoberg, E P; Sukura, A

    2013-04-01

    Cestodes of the genus Taenia are parasites of mammals, with mainly carnivores as definitive and herbivores as intermediate hosts. Various medium-sized cats, Lynx spp., are involved in the life cycles of several species of Taenia. The aim of the present study was to identify Taenia tapeworms in the Eurasian lynx (Lynx lynx) from Finland. In total, 135 tapeworms from 72 lynx were subjected to molecular identification based on sequences of 2 mtDNA regions, the cytochrome c oxidase subunit 1 and the NADH dehydrogenase subunit 1 genes. Available morphological characters of the rostellar hooks and strobila were compared. Two species of Taenia were found: T. laticollis (127 samples) and an unknown Taenia sp. (5 samples). The latter could not be identified to species based on mtDNA, and the rostellar hooks were short relative to those described among other Taenia spp. recorded in felids from the Holarctic region. In the phylogenetic analyses of mtDNA sequences, T. laticollis was placed as a sister species of T. macrocystis, and the unknown Taenia sp. was closely related to T. hydatigena and T. regis. Our analyses suggest that these distinct taeniid tapeworms represent a putative new species of Taenia. The only currently recognized definitive host is L. lynx and the intermediate host is unknown.

  18. Influence of tourism and traffic on the Eurasian lynx hunting activity and daily movements

    Directory of Open Access Journals (Sweden)

    Belotti, E.

    2012-01-01

    Full Text Available Human presence influences survival of large carnivores in several ways and even outdoor activities can be a source of disturbance. As ungulate prey provide the Eurasian lynx (Lynx lynx with food for several nights and the pattern of lynx activity is mainly shaped by searching for and consuming large prey, the need to move decreases strongly while the prey is eaten. However, during the day, human activity may drive lynx to move to safe shelters and habitat features such as dense vegetation may increase tolerance. In the Bohemian Forest (Czech Republic, we found 116 prey killed by five GPS–collared lynxes. We tested whether the kill sites were located farther from roads or tourist trails than a set of randomly generated locations and whether presence of roads or tourist trails and habitat structure influenced the distance ‘kill site to daytime resting sites’. At night, with low human activity, lynxes did not avoid roads and even selected the surroundings of tourist trails. The distance ‘kill site to daytime resting sites’ correlated negatively with presence of habitat concealment and distance to tourist trails, suggesting that outdoor activities may have to be considered in lynx management plans.

  19. Repeatability and consistency of individual behaviour in juvenile and adult Eurasian harvest mice

    Science.gov (United States)

    Schuster, Andrea C.; Carl, Teresa; Foerster, Katharina

    2017-04-01

    Knowledge on animal personality has provided new insights into evolutionary biology and animal ecology, as behavioural types have been shown to affect fitness. Animal personality is characterized by repeatable and consistent between-individual behavioural differences throughout time and across different situations. Behavioural repeatability within life history stages and consistency between life history stages should be checked for the independence of sex and age, as recent data have shown that males and females in some species may differ in the repeatability of behavioural traits, as well as in their consistency. We measured the repeatability and consistency of three behavioural and one cognitive traits in juvenile and adult Eurasian harvest mice ( Micromys minutus). We found that exploration, activity and boldness were repeatable in juveniles and adults. Spatial recognition measured in a Y Maze was only repeatable in adult mice. Exploration, activity and boldness were consistent before and after maturation, as well as before and after first sexual contact. Data on spatial recognition provided little evidence for consistency. Further, we found some evidence for a litter effect on behaviours by comparing different linear mixed models. We concluded that harvest mice express animal personality traits as behaviours were repeatable across sexes and consistent across life history stages. The tested cognitive trait showed low repeatability and was less consistent across life history stages. Given the rising interest in individual variation in cognitive performance, and in its relationship to animal personality, we suggest that it is important to gather more data on the repeatability and consistency of cognitive traits.

  20. Quantitative assessment of carbon sequestration reduction induced by disturbances in temperate Eurasian steppe

    Science.gov (United States)

    Chen, Yizhao; Ju, Weimin; Groisman, Pavel; Li, Jianlong; Propastin, Pavel; Xu, Xia; Zhou, Wei; Ruan, Honghua

    2017-11-01

    The temperate Eurasian steppe (TES) is a region where various environmental, social, and economic stresses converge. Multiple types of disturbance exist widely across the landscape, and heavily influence carbon cycling in this region. However, a current quantitative assessment of the impact of disturbances on carbon sequestration is largely lacking. In this study, we combined the boreal ecosystem productivity simulator (BEPS), the Shiyomi grazing model, and the global fire model (Glob-FIRM) to investigate the impact of the two major types of disturbance in the TES (i.e. domestic grazing and fire) on regional carbon sequestration. Model performance was validated using satellite data and field observations. Model outputs indicate that disturbance has a significant impact on carbon sequestration at a regional scale. The annual total carbon lost due to disturbances was 7.8 TgC yr‑1, accounting for 14.2% of the total net ecosystem productivity (NEP). Domestic grazing plays the dominant role in terrestrial carbon consumption, accounting for 95% of the total carbon lost from the two disturbances. Carbon losses from both disturbances significantly increased from 1999 to 2008 (R 2 = 0.82, P management of carbon sequestration in the vast grassland ecosystems.

  1. Genetic diversity of the Eurasian Otter (Lutra lutra) population in Israel.

    Science.gov (United States)

    Cohen, Tali Magory; Narkiss, Tamar; Dolev, Amit; Ben-Ari, Yossi; Kronfeld-Schor, Noga; Guter, Amichai; Saltz, David; Bar-Gal, Gila Kahila

    2013-03-01

    The Israeli population of Eurasian otter (Lutra lutra) marks the Palearctic southern boundary of the species' distribution in the Levant. During the 20th century, the otter population in Israel experienced a dramatic decline due to anthropogenic habitat alterations. Currently, the otter population in Israel is estimated at about 100 individuals and defined as "Critically Endangered". The aim of this research was to characterize the Israeli otter population in order to determine its genetic diversity and fragmentation state for conservation purposes. Monitoring spraint sites during 2000-2011 along active and historic otter distribution regions indicate both stable and unstable otter subpopulations, mainly along the Jordan River. Four otter subpopulations, representing 57 individuals, were characterized by 12 microsatellites, previously used to characterize the European otter populations. The genetic results indicated three subpopulations correlating with three geographical regions: the Hula Valley, Sea of Galilee, and the Harod Valley. A moderate genetic diversity (F (st) = 0.087-0.123) was found among the subpopulations, suggesting sporadic interactions between individuals from distinct geographical locations along the Jordan Rift Valley. The Israeli otter population was found to be very small, demographically remote and genetically distinct, harboring unique alleles absent from the studied European populations. Therefore, immediate conservation actions are recommended to prevent the deterioration of the isolated, unique, and critically endangered otter population in Israel.

  2. Geographic variation of craniodental morphology of the Eurasian otter (Lutra lutra) in East Asia.

    Science.gov (United States)

    Lau, Alice Ching Ching; Asahara, Masakazu; Han, Sung Yong; Kimura, Junpei

    2017-01-20

    Craniodental morphology of the Eurasian otter (Lutra lutra) in the Korean Peninsula, Japanese islands and Kinmen Island (Taiwan) was studied using geometric morphometrics to identify the skull variations between the populations. Forty adult skulls were examined (29 specimens from the Korean Peninsula, six from Shikoku, Honshu and Hokkaido of Japan, and five from Kinmen Island). Images of the dorsal and ventral views of the skull and the right lateral view of the mandible were analyzed. Specimens from the Korean Peninsula were larger than those from the Japanese islands and Kinmen Island. However, no correlation was observed between the shape variations in the three populations and the centroid size of the skull. The Mann-Whitney U-test showed that relative warps (RWs) RW1, RW2 and RW4 of the dorsal view and RW2 of the ventral view of the skull differed significantly between the populations. Some craniodental differences between the populations were seen in the dorsal and ventral views of the skull, mostly at the snout and parietal regions. The MANOVA test revealed significant differences between the specimens from the Japanese islands and Korean Peninsula and between the specimens from the Korean Peninsula and Kinmen Island. RWs plots showed an overlap of all three populations. In conclusion, the comparisons of the three examined populations revealed significant differences in their craniodental morphology.

  3. The Italian Action Plan for the endangered Eurasian otter Lutra lutra

    Directory of Open Access Journals (Sweden)

    Anna Loy

    2010-08-01

    Full Text Available Abstract
    Although recent evidence of the species recovery has been reported for many European countries, in Italy the Eurasian otter Lutra lutra is still considered endangered. Otter populations are confined to few river basins in the southern part of the peninsula and these are both geographically and genetically isolated from other European populations. This critical situation led the Italian Ministry of Environment to promote the production of an Action Plan for the otter in Italy, whose methods, aims and actions are briefly summarized.

    Riassunto
    Il Piano d'Azione Nazionale per la Lontra Lutra lutra
    Nonostante i segnali di recupero segnalati in molti paesi europei, la lontra Lutra lutra è ancora una delle specie più minacciate della fauna italiana, in virtù delle piccole dimensioni della popolazione e del suo isolamento , sia geografico, sia genetico, dal resto delle popolazioni europee. Sulla base di queste considerazioni il Ministero dell’Ambiente e della Tutela del territorio e del Mare ha recentemente promosso la realizzazione di un Piano d’Azione Nazionale per la Conservazione della Lontra, i cui contenuti, obiettivi, e azioni sono riassunti in questo lavoro.

    doi:10.4404/hystrix-21.1-4483

  4. Habitat correlates of the Eurasian otter Lutra lutra recolonizing Central Poland.

    Science.gov (United States)

    Romanowski, Jerzy; Brzeziński, Marcin; Zmihorski, Michał

    2013-04-01

    The increase in Eurasian otter Lutra lutra populations in their natural range and recolonization processes are recently observed in several European countries. We address the process of otter recolonization and habitat utilization in Central Poland over 14 years. Field surveys in 1998 and 2007 documented increase in occurrence of the species. The frequency of positive sites denoted 15 % in 1993, 38 % in 1998, and 89 % in 2007. Otter occurrence at study sites was positively affected by river width while negatively affected by presence of buildings at the site and river regulation. During the most intensive colonization process in the 1990s, the habitat preferences of the otter did not change. However, the sites inhabited by otters after 1998 were characterized by lower river width and tree cover and were more often located on regulated river sections, suggesting change in habitat tolerance during expansion. The otter abundance in transformed habitats is a result of increasing population numbers and the necessity to inhabit suboptimal sections of watercourses. Thus, it seems that presence-absence data for otter populations cannot be considered a reliable indicator of habitat quality, being depended of the population density.

  5. Condition-dependent expression of melanin-based coloration in the Eurasian kestrel

    Science.gov (United States)

    Piault, Romain; van den Brink, Valentijn; Roulin, Alexandre

    2012-05-01

    Melanin is the most common pigment in animal integuments and is responsible for some of the most striking ornaments. A central tenet of sexual selection theory states that melanin-based traits can signal absolute individual quality in any environment only if their expression is condition-dependent. Significant costs imposed by an ornament would ensure that only the highest quality individuals display the most exaggerated forms of the signal. Firm evidence that melanin-based traits can be condition-dependent is still rare in birds. In an experimental test of this central assumption, we report condition-dependent expression of a melanin-based trait in the Eurasian kestrel ( Falco tinnunculus). We manipulated nestling body condition by reducing or increasing the number of nestlings soon after hatching. A few days before fledging, we measured the width of sub-terminal black bands on the tail feathers. Compared to nestlings from enlarged broods, individuals raised in reduced broods were in better condition and thereby developed larger sub-terminal bands. Furthermore, in 2 years, first-born nestlings also developed larger sub-terminal bands than their younger siblings that are in poorer condition. This demonstrates that expression of melanin-based traits can be condition-dependent.

  6. Estimation of cultivable bacterial diversity in the cloacae and pharynx in Eurasian griffon vultures (Gyps fulvus).

    Science.gov (United States)

    Vela, Ana I; Casas-Díaz, Encarna; Fernández-Garayzábal, José F; Serrano, Emmanuel; Agustí, Susana; Porrero, María C; Sánchez del Rey, Verónica; Marco, Ignasi; Lavín, Santiago; Domínguez, Lucas

    2015-04-01

    In this work, we describe the biodiversity of cloacal and pharynx culture-based bacteria (commensal and pathogenic), in 75 Eurasian griffon vultures (Gyps fulvus) from two geographic areas. We address the question of whether the cultivable microbiota of vultures is organised into assemblages occurring by chance. In addition, we assess bacterial diversity in both anatomic regions and geographic areas. Bacterial diversity was represented by 26 Gram-negative and 20 Gram-positive genera. The most common genera were Escherichia, Enterococcus, Staphylococcus, Clostridium and Lactococcus. Escherichia coli and Enterococcus faecalis were the most common species in cloacal and pharyngeal samples. Staphylococcus and Erysipelothrix were isolated from the pharynx and Salmonella and Corynebacterium from the cloacae, and no Campylobacter was isolated from the cloacal swabs. Ten cloacal swabs were positive for Salmonella, of which five isolates were Salmonella enterica serotype 4,(5),12:i:-, one isolate was S. enterica serotype Derby, three isolates were S. enterica serotype 61:k:1,5,7 and one isolate was S. enterica serotype Infantis. The null modelling approach revealed that the commensal bacteria of vultures are not structured in assemblages. On the other hand, differences in bacterial genus and species richness between cloacal and pharyngeal samples or between geographic areas were clear, with the pharynx in vultures from both geographic areas being richer. The results of this study indicate also that vultures can serve as a reservoir of certain pathogenic zoonotic bacteria. The dissemination of these zoonotic pathogens in wildlife could be prevented by periodic sanitary surveys.

  7. Underlying causes of Eurasian midcontinental aridity in simulations of mid‐Holocene climate

    Science.gov (United States)

    Harrison, Sandy P.; Izumi, Kenji

    2017-01-01

    Abstract Climate model simulations uniformly show drier and warmer summers in the Eurasian midcontinent during the mid‐Holocene, which is not consistent with paleoenvironmental observations. The simulated climate results from a reduction in the zonal temperature gradient, which weakens westerly flow and reduces moisture flux and precipitation in the midcontinent. As a result, sensible heating is favored over evaporation and latent heating, resulting in substantial surface‐driven atmospheric warming. Thus, the discrepancy with the paleoenvironmental evidence arises initially from a problem in the simulated circulation and is exacerbated by feedback from the land surface. This region is also drier and warmer than indicated by observations in the preindustrial control simulations, and this bias arises in the same way: zonal flow and hence moisture flux into the midcontinent are too weak, and feedback from the land surface results in surface‐driven warming. These analyses suggest the need to improve those aspects of climate models that affect the strength of westerly circulation. PMID:29104328

  8. New evidence for the occurrence of Eurasian lynx (Lynx lynx) in medieval Britain

    Science.gov (United States)

    Hetherington, David A.; Lord, Tom C.; Jacobi, Roger M.

    2006-01-01

    The presence of Eurasian lynx as a former native species in Britain during the Holocene is known from bones recovered from several sites. AMS radiocarbon dating of lynx bone recovered from two sites in the Craven area of northern England gave 1842 +/- 35 14C yr BP and 1550 +/- 24 14C yr BP, together representing the youngest dates for lynx from England, and in the case of the latter, the youngest for Britain as a whole. These dates support the view that the game animal whose occurrence in the nearby Lake District is described in the early 7th century Cumbric text Pais Dinogad, and whose translation to date has been problematic, is a lynx. The occurrence of lynx in early medieval Britain shows that earlier periods of climate change, previously blamed for the species' extinction in Britain, were not responsible. Instead, anthropogenic factors such as severe deforestation, declining deer populations, and persecution, are likely to have caused the extirpation of lynx in Britain. Consequently, the lynx qualifies as a candidate for reintroduction. Large-scale reafforestation, the growth of deer populations, and more positive attitudes towards carnivores in modern society, could permit the restoration of lynx to Britain, particularly in Scotland.

  9. Identification of grouper (Epinephelus guaza), wreck fish (Polyprion americanus), and Nile perch (Lates niloticus) fillets by polyclonal antibody-based enzyme-linked immunosorbent assay.

    Science.gov (United States)

    Asensio, Luis; González, Isabel; Rodríguez, Miguel A; Mayoral, Belén; López-Calleja, Inés; Hernández, Pablo E; García, Teresa; Martín, Rosario

    2003-02-26

    An indirect enzyme-linked immunosorbent assay (ELISA) has been developed for the species identification of grouper (Epinephelus guaza), wreck fish (Polyprion americanus), and Nile perch (Lates niloticus) fillets. The assay was performed in two different formats, microtiter plates and immunostick tubes, and uses polyclonal antibodies raised in rabbits against muscle-soluble proteins of grouper (anti-GSP), wreck fish (anti-WSP), and Nile perch (anti-PSP). The antibodies were made species-specific by blocking them with the heterologous soluble muscle proteins. Immunorecognition of polyclonal antibodies adsorbed to their specific fish samples was made with swine antirabbit immunoglobulins conjugated to the enzyme horseradish peroxidase. Subsequent enzymatic conversion of the substrate allowed unequivocal identification of the species studied.

  10. Application of random amplified polymorphic DNA (RAPD) analysis for identification of grouper (Epinephelus guaza), wreck fish (Polyprion americanus), and Nile perch (Lates niloticus) fillets.

    Science.gov (United States)

    Asensio, Luis; González, Isabel; Fernández, Alicia; Rodríguez, Miguel A; Lobo, Esther; Hernández, Pablo E; García, Teresa; Martín, Rosario

    2002-02-01

    A random amplified polymorphic DNA (RAPD) method was developed for the specific identification of grouper (Epinephelus guaza), wreck fish (Polyprion americanus), and Nile perch (Lates niloticus) fillets. Using two different reaction primers (S1 and L1), RAPD analysis produced clear fingerprints from which the three fish species could be easily identified. This approach is rapid and reliable and offers the potential to detect fraudulent or unintentional mislabeling of these species in routine seafood authentication analysis.

  11. Microbiological properties and biogenic amines of whole pike-perch (Sander lucioperca, linnaeus 1758): a perspective on fish safety during postharvest handling practices and frozen storage.

    Science.gov (United States)

    Ehsani, Ali; Jasour, Mohammad Sedigh

    2012-12-01

    The biogenic amines (tyramine, histamine, cadaverine, and puterscine) and microbiological properties (mesophilic, psychrotrophic, and Pseudomonas spp.) of whole pike-perch (Sander lucioperca) was investigated during 2 d prestorage icing and 90 d frozen storage (-24 °C). At the end of ice storage, a noticeable increase only was found for puterscine level (P consumed without any health risks after 2 d icing condition and 90 d frozen storage. © 2012 Institute of Food Technologists®

  12. Effect of high pressure processing on textural and microbiological quality of pink perch (Nemipterus japonicus) sausage during chilled storage

    Science.gov (United States)

    Kunnath, Sarika; Panda, Satyen Kumar; Jaganath, Bindu; Gudipati, Venkateshwarlu

    2015-10-01

    The non-thermal high pressure (HP) processing was studied on fish sausage to enhance the quality during chilled storage. Pink perch (Nemipterus japonicus) sausages, packed in poly amide casing under vacuum were subjected to 400, 500 and 600 MPa pressures (dwell time: 10 min and ramp rate: 300 MPa/min) and compared with heat-set samples for physico-chemical and microbial quality parameters. Pressurized samples formed softer and glossier gels with a slight reduction in water-holding capacity. HP made the texture of sausage softer, cohesive and less chewy and gummier than heat-treated ones. Folding test seen higher acceptance values in samples treated at 500 and 600 MPa, during storage. Maximum log reduction in microbial count was observed in 600 MPa immediately, and significant difference in cooked and pressurized sausages was seen only up to 7th day. This revealed the potential application of HP in replacing conventional heat treatment for sausages preparation with enhanced shelf-life.

  13. Selection of perching site background color by Hamadryas feronia (Lepidoptera: Nymphalidae) in Costa Rica: implications for industrial melanism.

    Science.gov (United States)

    Murillo-Hiller, Luis Ricardo

    2012-09-01

    Observations of the increased frequency of melanic forms in moths of the genus Biston in Great Britain after the industrial revolution lead to the development of the theory of Industrial Melanism. Nonetheless, arguments against that interpretation of the experimental evidence have polarized acceptance of the concept. New evidence based on diurnal butterflies is more credible because it involves behavior that can be seen in action, during daylight, and because the natural history of the selected species is well known. An experiment was carried out in which three substrate colors (white, black, and gray) were employed to test the landing preferences of Hamadryas feronia. A marked preference was observed for landing on white and gray, and a chi-square (N=644 tests) showed evidence of a preference by males to land on white, and for females to land on gray. Black was rejected perhaps because it provides very little background matching with the butterfly's colors. The butterfly habit of perching selectively on particular color substrates is a genetically fixed behavior, where the males possibly choose white as a tactic to be noticed by females and attract them, whereas females prefer gray to enhance crypsis and avoid attracting predators.

  14. Pesticide residues in Nile tilapia (Oreochromis niloticus) and Nile perch (Lates niloticus) from Southern Lake Victoria, Tanzania

    Energy Technology Data Exchange (ETDEWEB)

    Henry, L. [Chemistry Department, University of Dar es Salaam. PO Box 35061, Dar es Salaam (Tanzania); Kishimba, M.A. [Chemistry Department, University of Dar es Salaam. PO Box 35061, Dar es Salaam (Tanzania)]. E-mail: kishimba@chem.udsm.ac.tz

    2006-03-15

    Nile tilapia (Oreochromis niloticus) and Nile perch (Lates niloticus) samples were collected from fish landing stations in nine riparian districts on the Tanzanian side of Lake Victoria and screened for residues of 64 organochlorine, organophosphorus, carbamate, and pyrethroid pesticides. The residue levels in the fish fillet were up to 0.003, 0.03 and 0.2 mg/kg fresh weight (0.7, 3.8 and 42 mg/kg lipid weight) of fenitrothion, DDT and endosulfan, respectively. Mean levels within sites were up to 0.002, 0.02 and 0.1 mg/kg fresh weight (0.5, 0.5 and 16 mg/kg lipid weight), respectively. The detection of higher levels of p,p'-DDT than the degradation products (p,p'-DDD and p,p'-DDE), and higher levels of endosulfan isomers ({alpha} and {beta}) than the sulphate, in fish samples, implied recent exposure of fish to DDT and endosulfan, respectively. Generally, most of the fish samples had residue levels above the average method detection limits (MDLs), but were within the calculated ADI. - Fish from Lake Victoria had relatively low pesticide levels.

  15. Growth and survival of a diallel cross for five strains of climbing perch (Anabas testudineus Bloch, 1792 in Thailand

    Directory of Open Access Journals (Sweden)

    Nitikorn Piwpong

    2016-09-01

    Full Text Available A complete diallel cross experiment was conducted with five strains of climbing perch (Anabas testudineus representing three wild populations collected from main river basins in Thailand and two farm populations in southern Thailand. Growth performance was recorded from 794 individually tagged progeny of the 24 different strain combinations after a grow-out period of about 130 d in an earthen pond. Least squares means of body weight at harvest and absolute growth rates were computed for each strain combination. The Chumphon strain showed the highest growth performance (81.1 ± 1.1 g. The Surat Thani × Chumphon (the first strain represents the sire showed the highest survival (65.4± 25.50% among the purebreds and the crossbreds. The domesticated gene pool had much better growth in aquaculture than the wild gene pool. The correlation between the least squares means of body weight and the survival rates in the 24 strain combinations was 0.51 (p < 0.05. The mean heterosis of all crossbreds across traits was negative (−10.2± 22.7%. Heterosis appeared to decrease when different gene pools were crossed. This suggests that there may be outbreeding depression. The advantage of crossbred performance was clearly not shown in the study.

  16. Bioaccumulation and assimilation efficiency of hexachlorobiphenyl (HCBP) in yellow perch as a function of both fish and diet lipid level

    Energy Technology Data Exchange (ETDEWEB)

    Dabrowska, H.; Fisher, S.W. [Ohio State Univ., Columbus, OH (United States)

    1995-12-31

    Evaluation of factors which control the uptake and bioaccumulation of lipophilic contaminants by fish and terrestrial animals is critical to the implementation of bioenergetics-based food web models used to ecological risk assessment. Among these factors some of the most important are feeding and egestion rates, lipid content of both an animal and its diet as well as chemical and food assimilation efficiencies. In this study, groups of juvenile yellow perch were fed lab-formulated low and high-lipid diet for a period of 3 months in order to establish a significant difference in body total lipid content. After that period fish were divided into subgroups and offered either low or high-lipid diet spiked with {sup 14}C-HCBP. Fish were fed contaminated diet for 1 month followed by 1 month of elimination period. Feeding rates during both periods were quantified. Fish (5 specimens) were collected at the beginning of the dietary exposure and every 10 days thereafter and analyzed for {sup 14}C-HCBP and lipid content. Bioaccumulation and assimilation efficiency related to the lipid level in fish and in the diets as well as to contaminant concentration in the diet will be discussed.

  17. First estimation of Eurasian lynx (Lynx lynx abundance and density using digital cameras and capture–recapture techniques in a German national park

    Directory of Open Access Journals (Sweden)

    Weingarth, K.

    2012-01-01

    Full Text Available Eurasian lynx are individually identifiable by their unique coat markings, making them ideal candidates for capture–recapture (CMR surveys. We evaluated the use of digital photography to estimate Eurasian lynx population abundance and density within the Bavarian Forest National Park. From November 2008 to January 2009 we placed 24 camera trap sites, each with two cameras facing each other on well–used walking tracks. The units were placed based on a systematic grid of 2.7 km. We captured five independent and three juvenile lynx and calculated abundance estimates using Program Mark. We also compared density estimates based on the MMDM method (Mean Maximum Distance Moved from telemetry data (½MMDMGPS and from camera trapping data (½MMDMCAM. We estimated that in an effectively sampled area of 664 km2 the Eurasian lynx density was 0.9 individuals/100 km2 with ½MMDMCAM. The Eurasian lynx density calculated with ½MMDMGPS was 0.4 individuals/100 km2 in an effectively sampled area of 1,381 km2. Our results suggest that long–term photographic CMR sampling on a large scale may be a useful tool to monitor population trends of Eurasian lynx in accordance with the Fauna–Flora–Habitat Directive of the European Union.

  18. Transport Corridors in the Russian Integration Projects, the Case of the Eurasian Economic Union

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    Olga A. Podberezkina

    2015-01-01

    Full Text Available The article discusses the political importance of transport corridors in terms of the development of integration projects in the post-Soviet space. The world is witnessing the formation of a single market and transport and communication infrastructure, which intensifies competition among regional and world leaders, both states and non-state actors, such as businesses, markets over the routes of transporting goods. In the medium and long term the value of the control over the transport routes will increase due to the dynamics of economic development in the Asia-Pacific region. Competition for the development of projects of international transport corridors (ITC between the leading countries in the region will increase, because the ITC entail the formation of a common political space, the reduction of tariff and customs barriers, which provides easy access to the markets of countries linked by ITCs and creates the preconditions for economic integration. The growing political importance of ITC is reflected in the fact that global leaders such as China, the US, the EU, are trying to create their own versions of international land transport corridors connecting Europe and Asia. China is trying to promote their transport project "Economic Belt Silk Road" European countries develop cooperation on ITC TRACECA with other countries of Eurasia. US also embody their interests through the implementation of the project by the ITC in Afghanistan. Transport corridors in Russia are seen as a way to integrate it into the global transportation system and logistics space. To do this, Russia needs to develop Eurasian transport corridors through its territory. As a result of the implementation of transport projects Russia will be able to ensure the transit of goods from China to Europe, which has a positive impact on the economic development of the regions through which they pass. Development of international transportation through Russia will unite many of the

  19. Developing E-Governance in the Eurasian Economic Union: Progress, Challenges and Prospects

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    Lyudmila Vidiasova

    2017-03-01

    Full Text Available he article provides an overview of e-governance development in the members of the Eurasian Economic Union (EEU. There is a lack of integrated research on e-governance in the EEU countries, although given the strengthening of this regional bloc, new information and communication technologies (ICT could serve as significant growth driver. Given the history and specifics of regional cooperation in the post-Soviet space and international best practices in ICT use in regional blocs, this article reviews the development of e-governance in the EEU members The research methodology was based on a three-stage concept of regionalism [Van Langenhov, Coste, 2005]. The study examines three key components: progress in developing e-governance, barriers to that development and future prospects. It used qualitative and quantitative methods. Data sources included the results of the United Nations E-Government rating, EEU countries’ regulations based on 3,200 documents and the authors’ expert survey, in which 18 experts (12 EEU representatives and six international experts participated. The study revealed the progress made by EEU countries in improving technological development and reducing human capital development indicators. The survey identified key barriers to e-governance development in the EEU: low motivation and information technology skills among civil servants, and citizens’ low computer literacy. The analysis of EEU members’ national economic priorities revealed a common focus on ICT development. The authors concluded that prospects for e-governance in the EEU were associated with strengthening regional cooperation in standardizing information systems, implementing one-stop-shop services, managing electronic documents and expanding online services. The authors presented two areas for developing e-governance within the EEU. The first is external integration, which, if strengthened, would affect the economy positivelyand optimize business processes

  20. Food availability and animal space use both determine cache density of Eurasian red squirrels.

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    Ke Rong

    Full Text Available Scatter hoarders are not able to defend their caches. A longer hoarding distance combined with lower cache density can reduce cache losses but increase the costs of hoarding and retrieving. Scatter hoarders arrange their cache density to achieve an optimal balance between hoarding costs and main cache losses. We conducted systematic cache sampling investigations to estimate the effects of food availability on cache patterns of Eurasian red squirrels (Sciurus vulgaris. This study was conducted over a five-year period at two sample plots in a Korean pine (Pinus koraiensis-dominated forest with contrasting seed production patterns. During these investigations, the locations of nest trees were treated as indicators of squirrel space use to explore how space use affected cache pattern. The squirrels selectively hoarded heavier pine seeds farther away from seed-bearing trees. The heaviest seeds were placed in caches around nest trees regardless of the nest tree location, and this placement was not in response to decreased food availability. The cache density declined with the hoarding distance. Cache density was lower at sites with lower seed production and during poor seed years. During seed mast years, the cache density around nest trees was higher and invariant. The pine seeds were dispersed over a larger distance when seed availability was lower. Our results suggest that 1 animal space use is an important factor that affects food hoarding distance and associated cache densities, 2 animals employ different hoarding strategies based on food availability, and 3 seed dispersal outside the original stand is stimulated in poor seed years.

  1. Spatiotemporal Variability of Snow Depth across Eurasian Continent from 1966 to 2008

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    Zhong, X.; Zhang, T.; Wang, K.

    2013-12-01

    Snow depth is one of the important parameters of snow cover, and it affects the surface energy balance, assessment of snow water equivalent, ecosystem, soil temperatures, and water cycle as a whole. In this study, the long-term observed snow depth from 1972 meteorological stations and snow course sites were used to investigate snow depth climatology and its spatiotemporal variations over Eurasian Continent from 1966 to 2008. Preliminary results showed that snow depth was affected by latitude, which in general snow depth increased with the increasing latitude. The higher values of snow depth were found in the northeastern European Russia, the east of western Siberia, the west of central Siberia, Kamchatka Peninsula, and some areas of Sakhalin. While the lower snow accumulation occurred in most areas of China except for the north of Xinjiang Autonomous Region of China, Northeast China, and some regions of the southwestern Tibet. Both of the trends in inter-annual variability of annual mean snow depth and annual maximum snow depth were not significant. However, the long-term monthly mean snow depth had obvious increasing trends from February to May. There were similar spatial distributions of linear trend coefficients of annual mean snow depth and annual maximum snow depth across the former Soviet Union (USSR). The most significant trends of changes in annual mean snow depth and annual maximum snow depth were found between 40° to 70°N. The obvious trends of variability in monthly mean snow depth appeared in the areas between 50° to 60°N. The significant decreasing trends in monthly mean snow depth were observed in most areas of China from February to March. This may be largely influenced by climate change, which leads to an advancing of the end date of snow cover.

  2. Range expansion and population dynamics of an invasive species: the Eurasian Collared-Dove (Streptopelia decaocto.

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    Spencer N Scheidt

    Full Text Available Invasive species offer ecologists the opportunity to study the factors governing species distributions and population growth. The Eurasian Collared-Dove (Streptopelia decaocto serves as a model organism for invasive spread because of the wealth of abundance records and the recent development of the invasion. We tested whether a set of environmental variables were related to the carrying capacities and growth rates of individual populations by modeling the growth trajectories of individual populations of the Collared-Dove using Breeding Bird Survey (BBS and Christmas Bird Count (CBC data. Depending on the fit of our growth models, carrying capacity and growth rate parameters were extracted and modeled using historical, geographical, land cover and climatic predictors. Model averaging and individual variable importance weights were used to assess the strength of these predictors. The specific variables with the greatest support in our models differed between data sets, which may be the result of temporal and spatial differences between the BBS and CBC. However, our results indicate that both carrying capacity and population growth rates are related to developed land cover and temperature, while growth rates may also be influenced by dispersal patterns along the invasion front. Model averaged multivariate models explained 35-48% and 41-46% of the variation in carrying capacities and population growth rates, respectively. Our results suggest that widespread species invasions can be evaluated within a predictable population ecology framework. Land cover and climate both have important effects on population growth rates and carrying capacities of Collared-Dove populations. Efforts to model aspects of population growth of this invasive species were more successful than attempts to model static abundance patterns, pointing to a potentially fruitful avenue for the development of improved invasive distribution models.

  3. Scent-marking behaviour and social dynamics in a wild population of Eurasian lynx Lynx lynx.

    Science.gov (United States)

    Vogt, Kristina; Zimmermann, Fridolin; Kölliker, Mathias; Breitenmoser, Urs

    2014-07-01

    Scent-marking is widespread among mammals and has been observed in many felid species. Although the behaviour is well-described, little is known about its function in wild felid populations. We investigated patterns of scent-marking and its role in intra- and intersexual communication among resident and non-resident Eurasian lynx Lynx lynx by observing interactions among wild lynx at natural marking sites by means of infrared camera traps. Marking activity of resident animals showed a peak during the mating season and was lowest during the time when females gave birth and lactated. Both sexes scent-marked, but male lynx visited marking sites much more often than females and marked relatively more often when visiting a site. Most visits to marking sites were by residents but we also observed scent-marking by non-residents. Juveniles were never observed marking. We found no evidence of lynx regularly renewing scent-marks after a certain 'expiry date' but the presence of a strange scent-mark triggered over-marking. Males responded similarly to the presence of another individual's scent-mark, irrespective of whether it was the top- or the underlying scent-mark in a mixture of scent-marks they encountered. Our results suggest that marking sites could serve as 'chemical bulletin boards', where male lynx advertise their presence and gain information on ownership relationships in a given area. Females placed their urine marks on top of the ones left by resident males, but further studies are needed to explain the functions of over-marking in females. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Collection of field reproductive data from carcasses of the female Eurasian lynx (Lynx lynx).

    Science.gov (United States)

    Axnér, E; Payan-Carreira, R; Setterlind, P; Åsbrink, J; Söderberg, A

    2013-11-01

    Information about reproductive physiology in the Eurasian lynx (Lynx lynx) would generate knowledge that could be useful in the management of the Swedish lynx population based on the knowledge about their reproductive potential and population development. Age-related differences in ovulation and implantation rates would affect the reproductive output and the development of the population. The aims of this study were to evaluate a protocol for collection of reproductive data from carcasses by comparisons with published field data and to generate data about reproduction in the Swedish lynx. Reproductive organs from 120 females that were harvested between March 1 and April 9 from 2009 to 2011 were collected and evaluated macroscopically for placental scars. Females had their first estrus as yearlings but did not have their first litter until the next season. Pregnancy rates were lower in 2-year-old females than in females aged 3 to 7 years but did not differ significantly from females aged 8 to 13 years (54.5%, 95.6%, and 75.0%, respectively). CL from the present season were morphologically distinctly different from luteal bodies from previous cycles (LBPC). All females ≥3 years had macroscopically visible LBPC, whereas only 67% of 22 to 23 months old females had one to three LBPC and no females lynx reproduction can be collected from reproductive organs retrieved after the death of the animals. Continuous monitoring of lynx reproductive organs would therefore make a valuable contribution to collection of field data, gathering information that can be useful for the management of lynx populations and potentially for the lynx as an indicator of environmental disturbances. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Histological and endocrine characterisation of the annual luteal activity in Eurasian lynx (Lynx lynx).

    Science.gov (United States)

    Carnaby, Kim; Painer, Johanna; Söderberg, Arne; Gavier-Widèn, Dolores; Göritz, Frank; Dehnhard, Martin; Jewgenow, Katarina

    2012-10-01

    Lynx presents a unique sexual cycle with persistent corpora lutea (CLs) and elevated serum progesterone (P₄) throughout parturition and lactation. In other mammals, CLs normally disintegrate after parturition, therefore the aim of our study was to characterise the annual life cycle of lynx CLs. Ovaries from Eurasian lynxes were obtained from the National Veterinary Institute in Sweden, where tissues from killed lynx were stored at -20 °C. Ovaries from 66 animals were weighed; each corpus luteum was segmented for histology and hormone analysis. Ovary and CLs weights were constant throughout the year, peaking during pregnancy. In non-pregnant lynxes, the seasonal level of intraluteal steroids was steady for P₄ (3.2±1.9 s.d. μg/g, n=53) and total oestrogens (18.3±15.5 s.d. ng/g, n=53). Within histology slides, structurally intact luteal cells were found throughout the year with the highest incidence in March/April; evidence of luteal regression was predominantly found in post-breeding season. Ovaries from pregnant animals contained two types of CLs. Group A was bigger in size with large luteal cells (P₄, 72.3±65.4 s.d. μg/g; oestrogen, 454.0±52.4 s.d. ng/g). In contrast, group B were smaller, with greater luteal regression and lower steroid concentrations (P₄, 8.3±2.9 s.d. μg/g; oestrogen, 31.5±20.4 s.d. ng/g). Our results suggest that structural luteolysis proceeds throughout the year and into next breeding cycle, resulting in two CLs types on the same ovary.

  6. Incentivizing the public to support invasive species management: eurasian milfoil reduces lakefront property values.

    Science.gov (United States)

    Olden, Julian D; Tamayo, Mariana

    2014-01-01

    Economic evaluations of invasive species are essential for providing comprehensive assessments of the benefits and costs of publicly-funded management activities, yet many previous investigations have focused narrowly on expenditures to control spread and infestation. We use hedonic modeling to evaluate the economic effects of Eurasian milfoil (Myriophyllum spicatum) invasions on lakefront property values of single-family homes in an urban-suburban landscape. Milfoil often forms dense canopies at the water surface, diminishing the value of ecosystem services (e.g., recreation, fishing) and necessitating expensive control and management efforts. We compare 1,258 lakeshore property sale transactions (1995-2006) in 17 lakes with milfoil and 24 un-invaded lakes in King County, Washington (USA). After accounting for structural (e.g., house size), locational (e.g., boat launch), and environmental characteristics (e.g., water clarity) of lakes, we found that milfoil has a significant negative effect on property sales price ($94,385 USD lower price), corresponding to a 19% decline in mean property values. The aggregate cost of milfoil invading one additional lake in the study area is, on average, $377,542 USD per year. Our study illustrates that invasive aquatic plants can significantly impact property values (and associated losses in property taxes that reduce local government revenue), justifying the need for management strategies that prevent and control invasions. We recommend coordinated efforts across Lake Management Districts to focus institutional support, funding, and outreach to prevent the introduction and spread of milfoil. This effort will limit opportunities for re-introduction from neighboring lakes and incentivize private landowners and natural resource agencies to commit time and funding to invasive species management.

  7. Quantitative assessments of water-use efficiency in Temperate Eurasian Steppe along an aridity gradient.

    Science.gov (United States)

    Chen, Yizhao; Li, Jianlong; Ju, Weimin; Ruan, Honghua; Qin, Zhihao; Huang, Yiye; Jeelani, Nasreen; Padarian, José; Propastin, Pavel

    2017-01-01

    Water-use efficiency (WUE), defined as the ratio of net primary productivity (NPP) to evapotranspiration (ET), is an important indicator to represent the trade-off pattern between vegetation productivity and water consumption. Its dynamics under climate change are important to ecohydrology and ecosystem management, especially in the drylands. In this study, we modified and used a late version of Boreal Ecosystem Productivity Simulator (BEPS), to quantify the WUE in the typical dryland ecosystems, Temperate Eurasian Steppe (TES). The Aridity Index (AI) was used to specify the terrestrial water availability condition. The regional results showed that during the period of 1999-2008, the WUE has a clear decreasing trend in the spatial distribution from arid to humid areas. The highest annual average WUE was in dry and semi-humid sub-region (DSH) with 0.88 gC mm-1 and the lowest was in arid sub-region (AR) with 0.22 gC mm-1. A two-stage pattern of WUE was found in TES. That is, WUE would enhance with lower aridity stress, but decline under the humid environment. Over 65% of the region exhibited increasing WUE. This enhancement, however, could not indicate that the grasslands were getting better because the NPP even slightly decreased. It was mainly attributed to the reduction of ET over 70% of the region, which is closely related to the rainfall decrease. The results also suggested a similar negative spatial correlation between the WUE and the mean annual precipitation (MAP) at the driest and the most humid ends. This regional pattern reflected the different roles of water in regulating the terrestrial ecosystems under different aridity levels. This study could facilitate the understanding of the interactions between terrestrial carbon and water cycles, and thus contribute to a sustainable management of nature resources in the dryland ecosystems.

  8. Effects of experimental brood size manipulation and gender on carotenoid levels of Eurasian kestrels Falco tinnunculus.

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    Toni Laaksonen

    Full Text Available BACKGROUND: Animals use carotenoid-pigments for coloration, as antioxidants and as enhancers of the immune system. Carotenoid-dependent colours can thus signal individual quality and carotenoids have also been suggested to mediate life-history trade-offs. METHODOLOGY: To examine trade-offs in carotenoid allocation between parents and the young, or between skin coloration and plasma of the parents at different levels of brood demand, we manipulated brood sizes of Eurasian kestrels (Falco tinnunculus. PRINCIPAL FINDINGS: Brood size manipulation had no overall effect on plasma carotenoid levels or skin hue of parents, but female parents had twice the plasma carotenoid levels of males. Males work physically harder than females and they might thus also use more carotenoids against oxidative stress than females. Alternatively, females could be gaining back the carotenoid stores they depleted during egg-laying by eating primarily carotenoid-rich food items during the early nestling stage. Fledglings in enlarged broods had higher plasma carotenoid concentrations than those in reduced broods. This difference was not explained by diet. In light of recent evidence from other species, we suggest it might instead be due to fledglings in enlarged broods having higher testosterone levels, which in turn increased plasma carotenoid levels. The partial cross-foster design of our experiment revealed evidence for origin effects (genetic or maternal on carotenoid levels of fledglings, but no origin-environment interaction. SIGNIFICANCE: These results from wild birds differ from studies in captivity, and thus offer new insights into carotenoid physiology in relation to division of parental care and demands of the brood.

  9. Living on the edge: Space use of Eurasian red squirrels in marginal high-elevation habitat

    Science.gov (United States)

    Romeo, Claudia; Wauters, Lucas A.; Preatoni, Damiano; Tosi, Guido; Martinoli, Adriano

    2010-11-01

    In marginal habitats located at the edge of a species' range, environmental conditions are frequently extreme and individuals may be subject to different selective pressures compared to central populations. These so-called edge or marginal populations tend to have lower densities and reproductive rates than populations located in more suitable habitats, but little is known about local adaptations in spacing behavior. We studied space use and social organization in a population of Eurasian red squirrels ( Sciurus vulgaris) in a high-elevation marginal habitat of dwarf mountain pine ( Pinus mugo) and compared it with spacing patterns in high-quality Scots pine ( Pinus sylvestris) forest at lower-elevation. Home ranges and core areas were larger in the marginal habitat. In both habitats, males used larger home ranges than females, but sex differences in core area size were significant only in the edge population. Patterns of core area overlap were similar in both habitats with intra-sexual territoriality among adult females and higher degrees of inter-sexual overlap, typical for the species throughout its range. However, low densities in the edge population resulted in higher female by males overlap in spring-summer, suggesting males increased home ranges and core areas during mating season to augment access to estrus females. Thus, in the marginal habitat, with low food abundance and low population densities, linked with extreme winter conditions, squirrels, especially males, used large home ranges. Finally, squirrels responded more strongly to variation in food availability (inverse relation between home range size and seed abundance), and even to fluctuations in density (inverse relation between core area size and density of animals of the same sex), in the marginal than in the high-quality habitat, suggesting high behavioral plasticity to respond to the ecological constraints in marginal habitats.

  10. Quantitative assessments of water-use efficiency in Temperate Eurasian Steppe along an aridity gradient.

    Directory of Open Access Journals (Sweden)

    Yizhao Chen

    Full Text Available Water-use efficiency (WUE, defined as the ratio of net primary productivity (NPP to evapotranspiration (ET, is an important indicator to represent the trade-off pattern between vegetation productivity and water consumption. Its dynamics under climate change are important to ecohydrology and ecosystem management, especially in the drylands. In this study, we modified and used a late version of Boreal Ecosystem Productivity Simulator (BEPS, to quantify the WUE in the typical dryland ecosystems, Temperate Eurasian Steppe (TES. The Aridity Index (AI was used to specify the terrestrial water availability condition. The regional results showed that during the period of 1999-2008, the WUE has a clear decreasing trend in the spatial distribution from arid to humid areas. The highest annual average WUE was in dry and semi-humid sub-region (DSH with 0.88 gC mm-1 and the lowest was in arid sub-region (AR with 0.22 gC mm-1. A two-stage pattern of WUE was found in TES. That is, WUE would enhance with lower aridity stress, but decline under the humid environment. Over 65% of the region exhibited increasing WUE. This enhancement, however, could not indicate that the grasslands were getting better because the NPP even slightly decreased. It was mainly attributed to the reduction of ET over 70% of the region, which is closely related to the rainfall decrease. The results also suggested a similar negative spatial correlation between the WUE and the mean annual precipitation (MAP at the driest and the most humid ends. This regional pattern reflected the different roles of water in regulating the terrestrial ecosystems under different aridity levels. This study could facilitate the understanding of the interactions between terrestrial carbon and water cycles, and thus contribute to a sustainable management of nature resources in the dryland ecosystems.

  11. Heat waves reduce ecosystem carbon sink strength in a Eurasian meadow steppe.

    Science.gov (United States)

    Qu, Luping; Chen, Jiquan; Dong, Gang; Jiang, Shicheng; Li, Linghao; Guo, Jixun; Shao, Changliang

    2016-01-01

    As a consequence of global change, intensity and frequency of extreme events such as heat waves (HW) have been increasing worldwide. By using a combination of continuous 60-year meteorological and 6-year tower-based carbon dioxide (CO2) flux measurements, we constructed a clear picture of a HWs effect on the dynamics of carbon, water, and vegetation on the Eurasian Songnen meadow steppe. The number of HWs in the Songnen meadow steppe began increasing since the 1980s and the rate of occurrence has advanced since the 2010s to higher than ever before. HWs can reduce the grassland carbon flux, while net ecosystem carbon exchange (NEE) will regularly fluctuate for 4-5 days during the HW before decreasing. However, ecosystem respiration (Re) and gross ecosystem production (GEP) decline from the beginning of the HW until the end, where Re and GEP will decrease 30% and 50%, respectively. When HWs last five days, water-use efficiency (WUE) will decrease by 26%, soil water content (SWC) by 30% and soil water potential (SWP) will increase by 38%. In addition, the soil temperature will still remain high after the HW although the air temperature will recover to its previous state. HWs, as an extreme weather event, have increased during the last two decades in the Songnen meadow steppe. HWs will reduce the carbon flux of the steppe and will cause a sustained impact. Drought may be the main reason why HWs decrease carbon flux. At the later stages of or after a HW, the ecosystem usually lacks water and the soil becomes so hot and dry that it prevents roots from absorbing enough water to maintain their metabolism. This is the main reason why this grassland carbon exchange decreases during and after HWs. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Fear in grasslands: the effect of Eurasian kestrels on skylark abundances

    Science.gov (United States)

    Martínez-Padilla, Jesús; Fargallo, Juan A.

    2008-05-01

    Predation has received considerable theoretical and empirical support in population regulation. The effect of predators, however, could be achieved in direct (killing) or indirect effects (such as displacement). In this paper, we explored the relationship between Eurasian kestrels Falco tinnunculus and skylarks Alauda arvensis in Mediterranean grasslands. First, we analysed the presence of skylarks in the kestrel diet over 9 years. We also compared a grassland area of experimentally increased kestrel density and a second grassland as control area to evaluate the direct or indirect effect on skylark abundance. We also considered two different habitats, grazed and ungrazed plots. If skylark abundance decreased as the kestrel breeding season progressed in high-density kestrel area compared with the control area, it would suggest a direct effect (predator hypothesis). If skylark abundance remains constant in both areas of contrasting kestrel density, it would suggest that skylarks avoid kestrels (avoidance hypothesis). We found that skylark abundance decreased in the kestrel area from the beginning of kestrel nest-box installation to recent years. The rate of skylark consumption decreased in a 9-year period as kestrel abundance increased, although the total amount skylark consumption did not show a decreasing trend. In addition, skylarks were more abundant in the kestrel-free area than in the kestrel area. Finally, we found that skylark abundance did not change through the kestrel breeding period in relation to grazing. We suggest that an increased breeding density of kestrels during their breeding period may force the skylarks to breed in other areas, which may explain the decline of their abundance.

  13. Long-Term Trends and Role of Climate in the Population Dynamics of Eurasian Reindeer.

    Science.gov (United States)

    Uboni, Alessia; Horstkotte, Tim; Kaarlejärvi, Elina; Sévêque, Anthony; Stammler, Florian; Olofsson, Johan; Forbes, Bruce C; Moen, Jon

    2016-01-01

    Temperature is increasing in Arctic and sub-Arctic regions at a higher rate than anywhere else in the world. The frequency and nature of precipitation events are also predicted to change in the future. These changes in climate are expected, together with increasing human pressures, to have significant impacts on Arctic and sub-Arctic species and ecosystems. Due to the key role that reindeer play in those ecosystems, it is essential to understand how climate will affect the region's most important species. Our study assesses the role of climate on the dynamics of fourteen Eurasian reindeer (Rangifer tarandus) populations, using for the first time data on reindeer abundance collected over a 70-year period, including both wild and semi-domesticated reindeer, and covering more than half of the species' total range. We analyzed trends in population dynamics, investigated synchrony among population growth rates, and assessed the effects of climate on population growth rates. Trends in the population dynamics were remarkably heterogeneous. Synchrony was apparent only among some populations and was not correlated with distance among population ranges. Proxies of climate variability mostly failed to explain population growth rates and synchrony. For both wild and semi-domesticated populations, local weather, biotic pressures, loss of habitat and human disturbances appear to have been more important drivers of reindeer population dynamics than climate. In semi-domesticated populations, management strategies may have masked the effects of climate. Conservation efforts should aim to mitigate human disturbances, which could exacerbate the potentially negative effects of climate change on reindeer populations in the future. Special protection and support should be granted to those semi-domesticated populations that suffered the most because of the collapse of the Soviet Union, in order to protect the livelihood of indigenous peoples that depend on the species, and the multi

  14. Long-Term Trends and Role of Climate in the Population Dynamics of Eurasian Reindeer.

    Directory of Open Access Journals (Sweden)

    Alessia Uboni

    Full Text Available Temperature is increasing in Arctic and sub-Arctic regions at a higher rate than anywhere else in the world. The frequency and nature of precipitation events are also predicted to change in the future. These changes in climate are expected, together with increasing human pressures, to have significant impacts on Arctic and sub-Arctic species and ecosystems. Due to the key role that reindeer play in those ecosystems, it is essential to understand how climate will affect the region's most important species. Our study assesses the role of climate on the dynamics of fourteen Eurasian reindeer (Rangifer tarandus populations, using for the first time data on reindeer abundance collected over a 70-year period, including both wild and semi-domesticated reindeer, and covering more than half of the species' total range. We analyzed trends in population dynamics, investigated synchrony among population growth rates, and assessed the effects of climate on population growth rates. Trends in the population dynamics were remarkably heterogeneous. Synchrony was apparent only among some populations and was not correlated with distance among population ranges. Proxies of climate variability mostly failed to explain population growth rates and synchrony. For both wild and semi-domesticated populations, local weather, biotic pressures, loss of habitat and human disturbances appear to have been more important drivers of reindeer population dynamics than climate. In semi-domesticated populations, management strategies may have masked the effects of climate. Conservation efforts should aim to mitigate human disturbances, which could exacerbate the potentially negative effects of climate change on reindeer populations in the future. Special protection and support should be granted to those semi-domesticated populations that suffered the most because of the collapse of the Soviet Union, in order to protect the livelihood of indigenous peoples that depend on the species

  15. Incentivizing the public to support invasive species management: eurasian milfoil reduces lakefront property values.

    Directory of Open Access Journals (Sweden)

    Julian D Olden

    Full Text Available Economic evaluations of invasive species are essential for providing comprehensive assessments of the benefits and costs of publicly-funded management activities, yet many previous investigations have focused narrowly on expenditures to control spread and infestation. We use hedonic modeling to evaluate the economic effects of Eurasian milfoil (Myriophyllum spicatum invasions on lakefront property values of single-family homes in an urban-suburban landscape. Milfoil often forms dense canopies at the water surface, diminishing the value of ecosystem services (e.g., recreation, fishing and necessitating expensive control and management efforts. We compare 1,258 lakeshore property sale transactions (1995-2006 in 17 lakes with milfoil and 24 un-invaded lakes in King County, Washington (USA. After accounting for structural (e.g., house size, locational (e.g., boat launch, and environmental characteristics (e.g., water clarity of lakes, we found that milfoil has a significant negative effect on property sales price ($94,385 USD lower price, corresponding to a 19% decline in mean property values. The aggregate cost of milfoil invading one additional lake in the study area is, on average, $377,542 USD per year. Our study illustrates that invasive aquatic plants can significantly impact property values (and associated losses in property taxes that reduce local government revenue, justifying the need for management strategies that prevent and control invasions. We recommend coordinated efforts across Lake Management Districts to focus institutional support, funding, and outreach to prevent the introduction and spread of milfoil. This effort will limit opportunities for re-introduction from neighboring lakes and incentivize private landowners and natural resource agencies to commit time and funding to invasive species management.

  16. Transcriptome analysis in sheepgrass (Leymus chinensis: a dominant perennial grass of the Eurasian Steppe.

    Directory of Open Access Journals (Sweden)

    Shuangyan Chen

    Full Text Available BACKGROUND: Sheepgrass [Leymus chinensis (Trin. Tzvel.] is an important perennial forage grass across the Eurasian Steppe and is known for its adaptability to various environmental conditions. However, insufficient data resources in public databases for sheepgrass limited our understanding of the mechanism of environmental adaptations, gene discovery and molecular marker development. RESULTS: The transcriptome of sheepgrass was sequenced using Roche 454 pyrosequencing technology. We assembled 952,328 high-quality reads into 87,214 unigenes, including 32,416 contigs and 54,798 singletons. There were 15,450 contigs over 500 bp in length. BLAST searches of our database against Swiss-Prot and NCBI non-redundant protein sequences (nr databases resulted in the annotation of 54,584 (62.6% of the unigenes. Gene Ontology (GO analysis assigned 89,129 GO term annotations for 17,463 unigenes. We identified 11,675 core Poaceae-specific and 12,811 putative sheepgrass-specific unigenes by BLAST searches against all plant genome and transcriptome databases. A total of 2,979 specific freezing-responsive unigenes were found from this RNAseq dataset. We identified 3,818 EST-SSRs in 3,597 unigenes, and some SSRs contained unigenes that were also candidates for freezing-response genes. Characterizations of nucleotide repeats and dominant motifs of SSRs in sheepgrass were also performed. Similarity and phylogenetic analysis indicated that sheepgrass is closely related to barley and wheat. CONCLUSIONS: This research has greatly enriched sheepgrass transcriptome resources. The identified stress-related genes will help us to decipher the genetic basis of the environmental and ecological adaptations of this species and will be used to improve wheat and barley crops through hybridization or genetic transformation. The EST-SSRs reported here will be a valuable resource for future gene-phenotype studies and for the molecular breeding of sheepgrass and other Poaceae species.

  17. Transcriptome Analysis in Sheepgrass (Leymus chinensis). A Dominant Perennial Grass of the Eurasian Steppe

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Shuangyan [Chinese Academy of Sciences (CAS), Institute of Botany (IB), Beijing; Huang, Xin [Chinese Academy of Sciences (CAS), Institute of Botany (IB), Beijing; Yang, Xiaohan [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Liu, Gongshe [Chinese Academy of Sciences (CAS), Institute of Botany (IB), Beijing

    2013-07-04

    BACKGROUND: Sheepgrass [Leymus chinensis (Trin.) Tzvel.] is an important perennial forage grass across the Eurasian Steppe and is known for its adaptability to various environmental conditions. However, insufficient data resources in public databases for sheepgrass limited our understanding of the mechanism of environmental adaptations, gene discovery and molecular marker development. RESULTS: The transcriptome of sheepgrass was sequenced using Roche 454 pyrosequencing technology. We assembled 952,328 high-quality reads into 87,214 unigenes, including 32,416 contigs and 54,798 singletons. There were 15,450 contigs over 500 bp in length. BLAST searches of our database against Swiss-Prot and NCBI non-redundant protein sequences (nr) databases resulted in the annotation of 54,584 (62.6%) of the unigenes. Gene Ontology (GO) analysis assigned 89,129 GO term annotations for 17,463 unigenes. We identified 11,675 core Poaceae-specific and 12,811 putative sheepgrass-specific unigenes by BLAST searches against all plant genome and transcriptome databases. A total of 2,979 specific freezing-responsive unigenes were found from this RNAseq dataset. We identified 3,818 EST-SSRs in 3,597 unigenes, and some SSRs contained unigenes that were also candidates for freezing-response genes. Characterizations of nucleotide repeats and dominant motifs of SSRs in sheepgrass were also performed. Similarity and phylogenetic analysis indicated that sheepgrass is closely related to barley and wheat. CONCLUSIONS: This research has greatly enriched sheepgrass transcriptome resources. The identified stress-related genes will help us to decipher the genetic basis of the environmental and ecological adaptations of this species and will be used to improve wheat and barley crops through hybridization or genetic transformation. The EST-SSRs reported here will be a valuable resource for future gene-phenotype studies and for the molecular breeding of sheepgrass and other Poaceae species.

  18. Transcriptome analysis in sheepgrass (Leymus chinensis): a dominant perennial grass of the Eurasian Steppe.

    Science.gov (United States)

    Chen, Shuangyan; Huang, Xin; Yan, Xueqing; Liang, Ye; Wang, Yuezhu; Li, Xiaofeng; Peng, Xianjun; Ma, Xingyong; Zhang, Lexin; Cai, Yueyue; Ma, Tian; Cheng, Liqin; Qi, Dongmei; Zheng, Huajun; Yang, Xiaohan; Li, Xiaoxia; Liu, Gongshe

    2013-01-01

    Sheepgrass [Leymus chinensis (Trin.) Tzvel.] is an important perennial forage grass across the Eurasian Steppe and is known for its adaptability to various environmental conditions. However, insufficient data resources in public databases for sheepgrass limited our understanding of the mechanism of environmental adaptations, gene discovery and molecular marker development. The transcriptome of sheepgrass was sequenced using Roche 454 pyrosequencing technology. We assembled 952,328 high-quality reads into 87,214 unigenes, including 32,416 contigs and 54,798 singletons. There were 15,450 contigs over 500 bp in length. BLAST searches of our database against Swiss-Prot and NCBI non-redundant protein sequences (nr) databases resulted in the annotation of 54,584 (62.6%) of the unigenes. Gene Ontology (GO) analysis assigned 89,129 GO term annotations for 17,463 unigenes. We identified 11,675 core Poaceae-specific and 12,811 putative sheepgrass-specific unigenes by BLAST searches against all plant genome and transcriptome databases. A total of 2,979 specific freezing-responsive unigenes were found from this RNAseq dataset. We identified 3,818 EST-SSRs in 3,597 unigenes, and some SSRs contained unigenes that were also candidates for freezing-response genes. Characterizations of nucleotide repeats and dominant motifs of SSRs in sheepgrass were also performed. Similarity and phylogenetic analysis indicated that sheepgrass is closely related to barley and wheat. This research has greatly enriched sheepgrass transcriptome resources. The identified stress-related genes will help us to decipher the genetic basis of the environmental and ecological adaptations of this species and will be used to improve wheat and barley crops through hybridization or genetic transformation. The EST-SSRs reported here will be a valuable resource for future gene-phenotype studies and for the molecular breeding of sheepgrass and other Poaceae species.

  19. Economic Integration and New Export Opportunities for the Eurasian Economic Union

    Directory of Open Access Journals (Sweden)

    Natalya Volchkova

    2016-12-01

    Full Text Available At a time when oil prices are low, non-oil exports are important for the members of the Eurasian Economic Union (EAEU. This study assesses the effects of the EAEU’s economic integration on the development of new exports. EAEU countries are far behind global export leaders in several categories according to the revealed comparative advantage, used by the Hausmann-Klinger method to assess national export baskets. Belarus exports the most products, and Russia and especially Armenia and Kazakhstan export notably fewer. The comparative advantages of Kazakhstan and Russia are concentrated mainly in minerals, chemical products and metals. The export structure for the other EAEU countries is more diverse, with a high share of foodstuffs in Armenia and textiles in Belarus. Kazakhstan and, to a greater extent, Belarus and Russia show a rather complex export basket, significantly ahead of Armenia according to this indicator. For the EAEU as an independent participant, its trade complexity index is higher than that for its member countries individually. This article uses the Hausmann-Klinger methodology to identify the future comparative advantages of the EAEU countries. These are product groups, towards which a structural transformation of the EAEU exports most likely occurs. The research focuses on the integration aspect of possible non-oil exports, seeking to identify goods, including chemicals and textiles, that can eventually provide a comparative advantage for the EAEU as a whole. Most of the products considered have a greater economic complexity than those in the EAEU’s current export basket, so would improve its overall export structure.

  20. The first record of Aelurostrongylus abstrusus (Angistrongylidae: Nematoda) in Eurasian lynx (Lynx lynx L.) from Poland based on fecal analysis.

    Science.gov (United States)

    Szczesna, Justyna; Popiołek, Marcin; Schmidt, Krzysztof; Kowalczyk, Rafał

    2006-01-01

    Thirty eight fecal samples of Eurasian Lynx (Lynx lynx L.) collected in Białowieza Primeval Forest (E Poland) in years 2001-2004 were analysed. The presence of Aelurostrongylus abstrusus (L1) larvae was evidenced by use of decantation and flotation methods. The general prevalence of the infection recorded during the study was 21.1%, whereas mean intensity was 11,5 (1-33 larvae per sample). To our knowledge, this is the first case of Aelurostrongylus abstrusus recorded in Euroasian lynx from Poland.

  1. Biliary parasite Pseudamphistomum truncatum (Opistorchiidae) in American mink (Mustela vison) and Eurasian otter (Lutra lutra) in Ireland.

    Science.gov (United States)

    Hawkins, Conall J; Caffrey, Joe M; Stuart, Peter; Lawton, Colin

    2010-09-01

    Native Eurasian otter (Lutra lutra) and introduced American mink (Mustela vison) carcasses collected throughout Ireland were screened for biliary parasites. Secondary intermediate hosts, Cyprinid fish, were also examined for Opistorchiid metacercariae. Twenty-nine mink and 24 otter gall bladders were screened for biliary parasites. A single mink and three otters were found to be infected with the digenetic trematode Pseudamphistomum truncatum. Eighty-nine percent of roach (Rutilus rutilus) from the River Shannon were infected with P. truncatum metacercariae, confirming the persistence of the parasite. This is the first record of the species in Ireland, and its recent introduction is probably related to the movement and release of Cyprinid fishes by anglers.

  2. Large impact of Eurasian lynx predation on roe deer population dynamics.

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    Henrik Andrén

    Full Text Available The effects of predation on ungulate populations depend on several factors. One of the most important factors is the proportion of predation that is additive or compensatory respectively to other mortality in the prey, i.e., the relative effect of top-down and bottom-up processes. We estimated Eurasian lynx (Lynx lynx kill rate on roe deer (Capreolus capreolus using radio-collared lynx. Kill rate was strongly affected by lynx social status. For males it was 4.85 ± 1.30 S.E. roe deer per 30 days, for females with kittens 6.23 ± 0.83 S.E. and for solitary females 2.71 ± 0.47 S.E. We found very weak support for effects of prey density (both for Type I (linear and Type II (non-linear functional responses and of season (winter, summer on lynx kill rate. Additionally, we analysed the growth rate in a roe deer population from 1985 to 2005 in an area, which lynx naturally re-colonized in 1996. The annual roe deer growth rate was lower after lynx re-colonized the study area, but it was also negatively influenced by roe deer density. Before lynx colonized the area roe deer growth rate was λ = 1.079 (± 0.061 S.E., while after lynx re-colonization it was λ = 0.94 (± 0.051 S.E.. Thus, the growth rate in the roe deer population decreased by Δλ = 0.14 (± 0.080 S.E. after lynx re-colonized the study area, which corresponded to the estimated lynx predation rate on roe deer (0.11 ± 0.042 S.E., suggesting that lynx predation was mainly additive to other mortality in roe deer. To conclude, this study suggests that lynx predation together with density dependent factors both influence the roe deer population dynamics. Thus, both top-down and bottom-up processes operated at the same time in this predator-prey system.

  3. Large impact of Eurasian lynx predation on roe deer population dynamics.

    Science.gov (United States)

    Andrén, Henrik; Liberg, Olof

    2015-01-01

    The effects of predation on ungulate populations depend on several factors. One of the most important factors is the proportion of predation that is additive or compensatory respectively to other mortality in the prey, i.e., the relative effect of top-down and bottom-up processes. We estimated Eurasian lynx (Lynx lynx) kill rate on roe deer (Capreolus capreolus) using radio-collared lynx. Kill rate was strongly affected by lynx social status. For males it was 4.85 ± 1.30 S.E. roe deer per 30 days, for females with kittens 6.23 ± 0.83 S.E. and for solitary females 2.71 ± 0.47 S.E. We found very weak support for effects of prey density (both for Type I (linear) and Type II (non-linear) functional responses) and of season (winter, summer) on lynx kill rate. Additionally, we analysed the growth rate in a roe deer population from 1985 to 2005 in an area, which lynx naturally re-colonized in 1996. The annual roe deer growth rate was lower after lynx re-colonized the study area, but it was also negatively influenced by roe deer density. Before lynx colonized the area roe deer growth rate was λ = 1.079 (± 0.061 S.E.), while after lynx re-colonization it was λ = 0.94 (± 0.051 S.E.). Thus, the growth rate in the roe deer population decreased by Δλ = 0.14 (± 0.080 S.E.) after lynx re-colonized the study area, which corresponded to the estimated lynx predation rate on roe deer (0.11 ± 0.042 S.E.), suggesting that lynx predation was mainly additive to other mortality in roe deer. To conclude, this study suggests that lynx predation together with density dependent factors both influence the roe deer population dynamics. Thus, both top-down and bottom-up processes operated at the same time in this predator-prey system.

  4. Structure and variability of the boundary current in the Eurasian Basin of the Arctic Ocean

    Science.gov (United States)

    Pnyushkov, Andrey V.; Polyakov, Igor V.; Ivanov, Vladimir V.; Aksenov, Yevgeny; Coward, Andrew C.; Janout, Markus; Rabe, Benjamin

    2015-07-01

    The Arctic Circumpolar Boundary Current (ACBC) transports a vast amount of mass and heat around cyclonic gyres of the deep basins, acting as a narrow, topographically-controlled flow, confined to the continental margins. Current observations during 2002-2011 at seven moorings along the major Atlantic Water (AW) pathway, complemented by an extensive collection of measured temperatures and salinities as well as results of state-of-the-art numerical modeling, have been used to examine the spatial structure and temporal variability of the ACBC within the Eurasian Basin (EB). These observations and modeling results suggest a gradual, six-fold decrease of boundary current speed (from 24 to 4 cm/s) on the route between Fram Strait and the Lomonosov Ridge, accompanied by a transformation of the vertical flow structure from mainly barotropic in Fram Strait to baroclinic between the area north of Spitsbergen and the central Laptev Sea continental slope. The relative role of density-driven currents in maintaining AW circulation increases with the progression of the ACBC eastward from Fram Strait, so that baroclinic ACBC forcing dominates over the barotropic in the eastern EB. Mooring records have revealed that waters within the AW and the cold halocline layers circulate in roughly the same direction in the eastern EB. The seasonal signal, meanwhile, is the most powerful mode of variability in the EB, contributing up to ~70% of the total variability in currents (resolved by moorings records) within the eastern EB. Seasonal signal amplitudes for current speed and AW temperature both decrease with the eastward progression of AW flow from source regions, and demonstrate strong interannual modulation. In the 2000s, the state of the EB (e.g., circulation pattern, thermohaline conditions, and freshwater balance) experienced remarkable changes. Results showing anomalous circulation patterns for an extended period of 30 months in 2008-2010 for the eastern EB, and a two-core AW

  5. Sexual conflict and consistency of offspring desertion in Eurasian penduline tit Remiz pendulinus

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    Pogány Ákos

    2008-09-01

    Full Text Available Abstract Background The trade-off between current and future parental investment is often different between males and females. This difference may lead to sexual conflict between parents over care provisioning in animals that breed with multiple mates. One of the most obvious manifestations of sexual conflict over care is offspring desertion whereby one parent deserts the young to increase its reproductive success at the expense of its mate. Offspring desertion is a wide-spread behavior, and its frequency often varies within populations. We studied the consistency of offspring desertion in a small passerine bird, the Eurasian penduline tit Remiz pendulinus, that has an extremely variable breeding system. Both males and females are sequentially polygamous, and a single parent (either the male or the female incubates the eggs and rears the young. About 28–40% of offspring are abandoned by both parents, and these offspring perish. Here we investigate whether the variation in offspring desertion in a population emerges either by each individual behaving consistently between different broods, or it is driven by the environment. Results Using a three-year dataset from Southern Hungary we show that offspring desertion by females is consistent between nests. Male desertion, however, depends on ambient environment, because all males desert their nests early in the season and some of them care late in the season. Therefore, within-population variation in parental care emerges by sexually different mechanisms; between-individual variation was responsible for the observed pattern of offspring desertion in females, whereas within-individual variation was responsible for the observed pattern in males. Conclusion To our knowledge, our study is the first that investigates repeatability of offspring desertion behavior in nature. The contrasting strategies of the sexes imply complex evolutionary trajectories in breeding behavior of penduline tits. Our results

  6. Long-term Radiation Budget Variability in the Northern Eurasian Region: Assessing the Interaction with Fire

    Science.gov (United States)

    Stackhouse, P. W.; Soja, A. J.; Zhang, T.; Mikovitz, J. C.

    2013-12-01

    In terms of global change, boreal regions are particularly important, because significant warming and change are already evident and significant future warming is predicted. Mean global air temperature has increased by 0.74°C in the last century, and temperatures are predicted to increase by 1.8°C to 4°C by 2090, depending on the Inter-governmental Panel on Climate Change (IPCC) scenario. Some of the greatest temperature increases are currently found in the Northern Eurasian winter and spring, which has led to longer growing seasons, increased potential evapotranspiration and extreme fire weather [Groisman et al., 2007]. In the Siberian Sayan, winter temperatures have already exceeded a 2090 Hadley Centre scenario (HadCM3GGa1) [Soja et al., 2007]. There is evidence of climate-induced change across the circumboreal in terms of increased infestations, alterations in vegetation and increased fire regimes (area burned, fire frequency, severity and number of extreme fire seasons). In this paper, we analyzed long-term surface radiation data sets from the NASA/GEWEX (Global Energy and Water Exchanges) Surface Radiation Budget data products, CERES Surface EBAF and SYN data products and also the available surface radiation measurements in the region. First, we show that during overlap years SRB and CERES data products agree very well in terms of anomalies and we'll use this fact to evaluate 30 years of satellite based estimates of the variability of downwelling SW parameters first corresponding to locations of surface measurements and then for the region as a whole. We also show the observed variability of other SW components such as the net SW and the albedo. Next we assess the variability of the downward and LW fluxes over time and compare these to variability observed in the surface temperature and other meteorological measurements. We assess anomalies on various spatial scales. Finally, we assess the correlation of this variability in specific locations to known fire

  7. Physiologically persistent Corpora lutea in Eurasian lynx (Lynx lynx) - longitudinal ultrasound and endocrine examinations intra-vitam.

    Science.gov (United States)

    Painer, Johanna; Jewgenow, Katarina; Dehnhard, Martin; Arnemo, Jon M; Linnell, John D C; Odden, John; Hildebrandt, Thomas B; Goeritz, Frank

    2014-01-01

    Felids generally follow a poly-estrous reproductive strategy. Eurasian lynx (Lynx lynx) display a different pattern of reproductive cyclicity where physiologically persistent corpora lutea (CLs) induce a mono-estrous condition which results in highly seasonal reproduction. The present study was based around a sono-morphological and endocrine study of captive Eurasian lynx, and a control-study on free-ranging lynx. We verified that CLs persist after pregnancy and pseudo-pregnancy for at least a two-year period. We could show that lynx are able to enter estrus in the following year, while CLs from the previous years persisted in structure and only temporarily reduced their function for the period of estrus onset or birth, which is unique among felids. The almost constant luteal progesterone secretion (average of 5 ng/ml serum) seems to prevent folliculogenesis outside the breeding season and has converted a poly-estrous general felid cycle into a mono-estrous cycle specific for lynx. The hormonal regulation mechanism which causes lynx to have the longest CL lifespan amongst mammals remains unclear. The described non-felid like ovarian physiology appears to be a remarkably non-plastic system. The lynx's reproductive ability to adapt to environmental and anthropogenic changes needs further investigation.

  8. Non cat-like ovarian cycle in the Eurasian and the Iberian lynx - ultrasonographical and endocrinological analysis.

    Science.gov (United States)

    Göritz, F; Dehnhard, M; Hildebrandt, T B; Naidenko, S V; Vargas, A; Martinez, F; López-Bao, J V; Palomares, F; Jewgenow, K

    2009-07-01

    The Iberian lynx is considered the most endangered felid species. Therefore, an ex situ conservation program was initiated to protect this species from extinction. Additional knowledge on lynx reproduction biology and reliable methods for reproductive monitoring are important for developing a captive breeding program. The aim of this study in lynx was to implement transrectal ultrasonography to visualize ovarian structures (follicles, corpora lutea) and to assess ovarian activity in addition to analysis of serum progesterone and oestradiol. Because of limited access to Iberian lynxes, the less-endangered Eurasian lynx and bobcat were also studied in this comparative study. Recent endocrinological studies based on faecal and urinary progesterone and oestrogen metabolites revealed that steroid profiles in both these species were alike and did not follow the typical pattern of other felids. Pregnancy diagnosis was not possible, since progesterone concentrations did not differ between pregnant and pseudopregnant animals. Progesterone was also detected after parturition as well as after weaning until the onset of a new oestrous cycle. In the present study, the presence of corpora lutea during the non-breeding season was confirmed by ultrasonography and by elevated serum levels of progesterone averaging 3.56 +/- 1.3 ng/ml in Eurasian and 6.1 +/- 0.26 ng/ml in Iberian lynx, respectively. The ultrasonographical findings on the ovarian structures suggest strongly that corpora lutea developed after ovulation stay active until November and regress before the onset of the next oestrus.

  9. Physiologically Persistent Corpora lutea in Eurasian Lynx (Lynx lynx) – Longitudinal Ultrasound and Endocrine Examinations Intra-Vitam

    Science.gov (United States)

    Painer, Johanna; Jewgenow, Katarina; Dehnhard, Martin; Arnemo, Jon M.; Linnell, John D. C.; Odden, John; Hildebrandt, Thomas B.; Goeritz, Frank

    2014-01-01

    Felids generally follow a poly-estrous reproductive strategy. Eurasian lynx (Lynx lynx) display a different pattern of reproductive cyclicity where physiologically persistent corpora lutea (CLs) induce a mono-estrous condition which results in highly seasonal reproduction. The present study was based around a sono-morphological and endocrine study of captive Eurasian lynx, and a control-study on free-ranging lynx. We verified that CLs persist after pregnancy and pseudo-pregnancy for at least a two-year period. We could show that lynx are able to enter estrus in the following year, while CLs from the previous years persisted in structure and only temporarily reduced their function for the period of estrus onset or birth, which is unique among felids. The almost constant luteal progesterone secretion (average of 5 ng/ml serum) seems to prevent folliculogenesis outside the breeding season and has converted a poly-estrous general felid cycle into a mono-estrous cycle specific for lynx. The hormonal regulation mechanism which causes lynx to have the longest CL lifespan amongst mammals remains unclear. The described non-felid like ovarian physiology appears to be a remarkably non-plastic system. The lynx's reproductive ability to adapt to environmental and anthropogenic changes needs further investigation. PMID:24599348

  10. Physiologically persistent Corpora lutea in Eurasian lynx (Lynx lynx - longitudinal ultrasound and endocrine examinations intra-vitam.

    Directory of Open Access Journals (Sweden)

    Johanna Painer

    Full Text Available Felids generally follow a poly-estrous reproductive strategy. Eurasian lynx (Lynx lynx display a different pattern of reproductive cyclicity where physiologically persistent corpora lutea (CLs induce a mono-estrous condition which results in highly seasonal reproduction. The present study was based around a sono-morphological and endocrine study of captive Eurasian lynx, and a control-study on free-ranging lynx. We verified that CLs persist after pregnancy and pseudo-pregnancy for at least a two-year period. We could show that lynx are able to enter estrus in the following year, while CLs from the previous years persisted in structure and only temporarily reduced their function for the period of estrus onset or birth, which is unique among felids. The almost constant luteal progesterone secretion (average of 5 ng/ml serum seems to prevent folliculogenesis outside the breeding season and has converted a poly-estrous general felid cycle into a mono-estrous cycle specific for lynx. The hormonal regulation mechanism which causes lynx to have the longest CL lifespan amongst mammals remains unclear. The described non-felid like ovarian physiology appears to be a remarkably non-plastic system. The lynx's reproductive ability to adapt to environmental and anthropogenic changes needs further investigation.

  11. Considerations regarding the occurence of the Eurasian Beaver (Castor fiber Linnaeus 1758 in the Danube Delta (Romania

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    ALEXE Vasile

    2012-09-01

    Full Text Available On its original Romanian name - breb, the Eurasian Beaver (Castor fiber extinct at us for almost two centuries and reintroduced in some areas of the country, at present is better known under the name of his North American relative, beaver. In the last decades, this specie has been reintroduced within in its old habitats from where itwas extinct, especially under the effect of human pressure. Since 1998, reinsertion actions took place in Romania, in many areas, the closest one to Danube Delta area being the lower part of Ialomita river. By 2011 epigraphic or paleozoology evidences about the presence of this mammalian into the actual Delta have not been found, except the Lower Danube, up to Isaccea, but also near Dobrogea Plateau in Murighiol area. Its last Paleontology evidences come from early medieval period. Until now, the actual delta was considered a territory inappropriate for the Eurasian Beaver, due to high fluctuations of the water levels. But, in April 2011, the spontaneous appearance of the European beaver near Maliuc area was proved, a copy killed by poachers. In July 2011, a Beaver injured after the collision with a boat was found and scientifically investigated. The future observations will have to document if this mammal extends its habitat up here or remains an erratic appearance. In case of success of spontaneous colonization, its consequences and effects on the environment in general and on biodiversity inparticular are required to be monitored.

  12. The Use of Acceleration to Code for Animal Behaviours; A Case Study in Free-Ranging Eurasian Beavers Castor fiber.

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    Patricia M Graf

    Full Text Available Recent technological innovations have led to the development of miniature, accelerometer-containing electronic loggers which can be attached to free-living animals. Accelerometers provide information on both body posture and dynamism which can be used as descriptors to define behaviour. We deployed tri-axial accelerometer loggers on 12 free-ranging Eurasian beavers Castor fiber in the county of Telemark, Norway, and on four captive beavers (two Eurasian beavers and two North American beavers C. canadensis to corroborate acceleration signals with observed behaviours. By using random forests for classifying behavioural patterns of beavers from accelerometry data, we were able to distinguish seven behaviours; standing, walking, swimming, feeding, grooming, diving and sleeping. We show how to apply the use of acceleration to determine behaviour, and emphasise the ease with which this non-invasive method can be implemented. Furthermore, we discuss the strengths and weaknesses of this, and the implementation of accelerometry on animals, illustrating limitations, suggestions and solutions. Ultimately, this approach may also serve as a template facilitating studies on other animals with similar locomotor modes and deliver new insights into hitherto unknown aspects of behavioural ecology.

  13. Spatiotemporal variability of snow depth across the Eurasian continent from 1966 to 2012

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    X. Zhong

    2018-01-01

    Full Text Available Snow depth is one of the key physical parameters for understanding land surface energy balance, soil thermal regime, water cycle, and assessing water resources from local community to regional industrial water supply. Previous studies by using in situ data are mostly site specific; data from satellite remote sensing may cover a large area or global scale, but uncertainties remain large. The primary objective of this study is to investigate spatial variability and temporal change in snow depth across the Eurasian continent. Data used include long-term (1966–2012 ground-based measurements from 1814 stations. Spatially, long-term (1971–2000 mean annual snow depths of >20 cm were recorded in northeastern European Russia, the Yenisei River basin, Kamchatka Peninsula, and Sakhalin. Annual mean and maximum snow depth increased by 0.2 and 0.6 cm decade−1 from 1966 through 2012. Seasonally, monthly mean snow depth decreased in autumn and increased in winter and spring over the study period. Regionally, snow depth significantly increased in areas north of 50° N. Compared with air temperature, snowfall had greater influence on snow depth during November through March across the former Soviet Union. This study provides a baseline for snow depth climatology and changes across the Eurasian continent, which would significantly help to better understanding climate system and climate changes on regional, hemispheric, or even global scales.

  14. Assessment of Water Use in Pan-Eurasian and African Continents by ETMonitor with Multi-Source Satellite Data

    Science.gov (United States)

    Zheng, Chaolei; Jia, Li; Hu, Guangcheng; Menenti, Massimo; Lu, Jing; Zhou, Jie; Wang, Kun; Li, Zhansheng

    2017-02-01

    The Pan-Eurasian and African Continents are characterized by large ranges of climates varying from humid, semi-humid, semi-arid and arid regions, and great challenges exist in water allocation for different sectors that related to water resource and food security, which depends strongly on the water use information. Quantitative information on water use is also important to understand the effectiveness of water allocation and further to prevent from water stress resulted by drought in water-scarce regions. Explosive development of satellite remote sensing observations provide great chance to provide useful spatiotemporal information for quantifying the water use at regional to global scales. In this paper, a process-based model ETMonitor was used in combination with biophysical and hydrological parameters retrieved from earth observations to estimate the actual evapotranspiration, i.e. the agricultural and ecological water use. The total water use is also partitioned into beneficial part, e.g. plant transpiration, and non-beneficial part, e.g. soil evaporation and canopy rainfall interception, according to the water accounting framework. The estimated water use show good agreements with the ground observation, indicating the ability of ETMonitor for global and continental scale water use estimation. The spatial and temporal patterns of the water use in the Pan-Eurasian and African Continents were further analysed, while large spatial variation of water use was convinced. Current study also highlights the great capability of satellite observations in studying the regional water resource and continental water cycle.

  15. Identification of Nile perch (Lates niloticus), grouper (Epinephelus guaza), and wreck fish (Polyprion americanus) fillets by PCR amplification of the 5S rDNA gene.

    Science.gov (United States)

    Asensio, L; González, I; Fernández, A; Céspedes, A; Rodríguez, M A; Hernández, P E; García, T; Martín, R

    2001-01-01

    Nile perch (Lates niloticus), grouper (Epinephelus guaza), and wreck fish (Polyprion americanus) were differentiated by polymerase chain reaction (PCR) amplification of the nuclear 5S rDNA gene. The design of 3 species-specific primers complementary to the nontranscribed intergenic spacer region from the 5S rDNA molecule allowed amplification of clearly distinguishable gene fragments in each fish species. This approach is rapid and reliable and offers the potential to detect fraudulent or unintentional mislabeling of these species in routine seafood authentication analysis.

  16. PCR-SSCP: a simple method for the authentication of grouper (Epinephelus guaza), wreck fish (Polyprion americanus), and Nile perch (Lates niloticus) fillets.

    Science.gov (United States)

    Asensio, L; González, I; Fernández, A; Rodríguez, M A; Hernández, P E; García, T; Martín, R

    2001-04-01

    A method of DNA analysis has been developed to verify the authenticity of grouper (Epinephelus guaza), wreck fish (Polyprion americanus), and Nile perch (Lates niloticus) fillets. A short fragment (208 bp) of the mitochondrial 12S rRNA gene was amplified by the polymerase chain reaction and analyzed by single-strand conformation polymorphism to get species-specific patterns of single-stranded DNA (ssDNA). DNA strands were separated by native polyacrylamide gel electrophoresis and visualized by silver staining. Discrimination among the three fish species studied was possible, because each one expressed a specific ssDNA pattern.

  17. Effect of closed v. intermittent-flow respirometry on hypoxia tolerance in the shiner perch Cymatogaster aggregata

    DEFF Research Database (Denmark)

    Snyder, S.; Nadler, L.E.; Bayley, J.S.

    2016-01-01

    hypoxia tolerance in closed respirometry is consistent with additional stress, caused by a build-up of ammonia and carbon dioxide and a faster rate in dissolved oxygen decline. The results indicate that these two methods of determining hypoxia tolerance in aquatic organisms are not comparable......This study compares the critical oxygen saturation (O2 crit ) levels of the shiner perch Cymatogaster aggregata obtained using two different methods wherein hypoxia is induced either by the fish's respiration (closed respirometry) or by degassing oxygen with nitrogen (intermittent-flow respirometry...

  18. Welfare of organic laying hens kept at different indoor stocking densities in a multi-tier aviary system. II: live weight, health measures and perching

    DEFF Research Database (Denmark)

    Steenfeldt, Sanna; Nielsen, Birte L.

    2015-01-01

    Multi-tier aviary systems, where conveyor belts below the tiers remove the manure at regular intervals, are becoming more common in organic egg production. The area on the tiers can be included in the net area available to the hens (also referred to as usable area) when calculating maximum indoor...... stocking densities in organic systems within the EU. In this article, results on live weight, health measures and perching are reported for organic laying hens housed in a multi-tier system with permanent access to a veranda and kept at stocking densities (D) of 6, 9 and 12 hens/m2 available floor area...

  19. An update of hydrologic conditions and distribution of selected constituents in water, eastern Snake River Plain aquifer and perched groundwater zones, Idaho National Laboratory, Idaho, emphasis 2012-15

    Science.gov (United States)

    Bartholomay, Roy C.; Maimer, Neil V.; Rattray, Gordon W.; Fisher, Jason C.

    2017-04-10

    Since 1952, wastewater discharged to in ltration ponds (also called percolation ponds) and disposal wells at the Idaho National Laboratory (INL) has affected water quality in the eastern Snake River Plain (ESRP) aquifer and perched groundwater zones underlying the INL. The U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Energy, maintains groundwater-monitoring networks at the INL to determine hydrologic trends and to delineate the movement of radiochemical and chemical wastes in the aquifer and in perched groundwater zones. This report presents an analysis of water-level and water-quality data collected from the ESRP aquifer, multilevel monitoring system (MLMS) wells in the ESRP aquifer, and perched groundwater wells in the USGS groundwater monitoring networks during 2012-15.

  20. Individual migration patterns of Eurasian golden plovers Pluvialis apricaria breeding in Swedish Lapland; examples of cold spell-induced winter movements

    NARCIS (Netherlands)

    Machin, Paula; Fernandez-Elipe, Juan; Flores, Manuel; Fox, James W.; Aguirre, Jose I.; Klaassen-, Raymond H. G.

    2015-01-01

    Tracking studies normally focus on long-distance migrants, meaning that our understanding about short-distance migration remains limited. In this study, we present the first individual tracks of the Eurasian golden plover Pluvialis apricaria, a short-distance migrant, which were tracked from a

  1. Individual migration patterns of Eurasian golden plovers Pluvialis apricaria breeding in Swedish Lapland : Examples of cold spell-induced winter movements

    NARCIS (Netherlands)

    Machin, Paula; Fernandez-Elipe, Juan; Flores, Manuel; Fox, James W.; Aguirre, Jose I.; Klaassen-, Raymond H. G.

    2015-01-01

    Tracking studies normally focus on long-distance migrants, meaning that our understanding about short-distance migration remains limited. In this study, we present the first individual tracks of the Eurasian golden plover Pluvialis apricaria, a short-distance migrant, which were tracked from a

  2. Reassortant highly pathogenic influenza A H5N2 virus containing gene segments related to Eurasian H5N8 in British Columbia, Canada, 2014.

    Science.gov (United States)

    Pasick, John; Berhane, Yohannes; Joseph, Tomy; Bowes, Victoria; Hisanaga, Tamiko; Handel, Katherine; Alexandersen, Soren

    2015-03-25

    In late November 2014 higher than normal death losses in a meat turkey and chicken broiler breeder farm in the Fraser Valley of British Columbia initiated a diagnostic investigation that led to the discovery of a novel reassortant highly pathogenic avian influenza (HPAI) H5N2 virus. This virus, composed of 5 gene segments (PB2, PA, HA, M and NS) related to Eurasian HPAI H5N8 and the remaining gene segments (PB1, NP and NA) related to North American lineage waterfowl viruses, represents the first HPAI outbreak in North American poultry due to a virus with Eurasian lineage genes. Since its first appearance in Korea in January 2014, HPAI H5N8 spread to Western Europe in November 2014. These European outbreaks happened to temporally coincide with migratory waterfowl movements. The fact that the British Columbia outbreaks also occurred at a time associated with increased migratory waterfowl activity along with reports by the USA of a wholly Eurasian H5N8 virus detected in wild birds in Washington State, strongly suggest that migratory waterfowl were responsible for bringing Eurasian H5N8 to North America where it subsequently reassorted with indigenous viruses.

  3. Measurements of Cd, Cu, Pb and Zn in the lower reaches of major Eurasian arctic rivers using trace metal clean techniques

    Energy Technology Data Exchange (ETDEWEB)

    Guay, Christopher K.H., E-mail: cguay@pmstllc.co [Pacific Marine Sciences and Technology, 3503 Lakeshore Avenue, Suite 5, Oakland, CA 94610 (United States); Zhulidov, Alexander V. [South Russian Regional Centre for Preparation and Implementation of International Projects (CPPI-S), 200/1 Stachki Av., No. 301, Rostov-on-Don 344090 (Russian Federation); Robarts, Richard D. [UNEP GEMS/Water Programme, c/o National Water Research Institute, National Hydrology Research Centre, 11 Innovation Blvd., Saskatoon, Saskatchewan S7N 3H5 (Canada); Zhulidov, Daniel A.; Gurtovaya, Tatiana Yu. [South Russian Regional Centre for Preparation and Implementation of International Projects (CPPI-S), 200/1 Stachki Av., No. 301, Rostov-on-Don 344090 (Russian Federation); Holmes, Robert M. [The Ecosystems Center, Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543 (United States); Headley, John V. [Aquatic Ecosystem Protection Research Branch, National Water Research Institute, National Hydrology Research Centre, 11 Innovation Blvd., Saskatoon, Saskatchewan S7N 3H5 (Canada)

    2010-02-15

    Concentrations of dissolved and particulate Cd, Cu, Pb and Zn were determined in samples collected in summer 1998 from the lower reaches of six major Eurasian arctic rivers: the Onega, Severnaya Dvina, Mezen, Pechora, Ob and Yenisey. These data comprise some of the earliest measurements of trace metals in Eurasian arctic rivers above the estuaries using recognized clean techniques. Significant (alpha = 0.05) differences were observed among mean concentrations of particulate metals in the individual rivers (F <= 0.006), with highest levels overall observed in the Severnaya Dvina and Yenisey. No significant differences were observed among mean concentrations of dissolved metals in the individual rivers (F = 0.10-0.84). Contributions from anthropogenic sources are suggested by comparison of trace metal ratios in the samples to crustal abundances. These results establish a baseline for assessing future responses of Eurasian arctic river systems to climate-related environmental changes and shifting patterns of pollutant discharge. - We report some of the earliest reliable trace metal data for major Eurasian arctic rivers.

  4. Eurasian Higher Education Leaders Forum: Graduate Employability in the 21st Century. Conference Proceedings (4th, Astana, Kazakhstan, June 11-12, 2015)

    Science.gov (United States)

    Sagintayeva, Aida, Ed.; Kurakbayev, Kairat, Ed.

    2015-01-01

    This collection of papers introduces the proceedings of the Fourth Annual Conference-Eurasian Higher Education Leaders' Forum held on the 11-12 June, 2015 at Nazarbayev University in Astana, Kazakhstan. Our presenters come from different professional backgrounds including higher education institutions, national business companies as well as…

  5. Genetic structure within and among regional populations of the Eurasian badger (Meles meles) from Denmark and the Netherlands

    DEFF Research Database (Denmark)

    Zande, L. van de; Vliet, M. van de; Pertoldi, C.

    2007-01-01

    The Eurasian badger Meles meles has a wide distribution area ranging from Japan to Ireland. In western Europe badger habitats are severely disturbed by anthropogenic factors, leading to fragmentation into subpopulations and formation of a metapopulation substructuring of once continuous panmictic...

  6. Potential utility of environmental DNA for early detection of Eurasian watermilfoil (Myriophyllum spicatum)

    Science.gov (United States)

    Newton, Jeremy; Sepulveda, Adam; Sylvester, K; Thum, Ryan

    2016-01-01

    Considering the harmful and irreversible consequences of many biological invasions, early detection of an invasive species is an important step toward protecting ecosystems (Sepulveda et al. 2012). Early detection increases the probability that suppression or eradication efforts will be successful because invasive populations are small and localized (Vander Zanden et al. 2010). However, most invasive species are not detected early because current tools have low detection probabilities when target species are rare and the sampling effort required to achieve acceptable detection capabilities with current tools is seldom tractable (Jerde et al. 2011). As a result, many invasive species go undetected until they are abundant and suppression efforts become costly. Novel DNA-based surveillance tools have recently revolutionized early detection abilities using environmental DNA (eDNA) present in the water (Darling and Mahon 2011, Bohmann et al. 2014). In brief, eDNA monitoring enables the identification of organisms from DNA present and collected in water samples. Aquatic and semiaquatic organisms release DNA contained in sloughed, damaged, or partially decomposed tissue and waste products into the water and molecular techniques allow this eDNA in the water column to be identified from simple and easy-tocollect water samples (Darling and Mahon 2011). Despite limited understanding of the production, persistence, and spread of DNA in water (Barnes et al. 2014), eDNA monitoring has been applied not only to invasive species (Jerde et al. 2011), but also to species that are rare, endangered, or highly elusive (Spear et al. 2014). However, most eDNA research and monitoring has focused on detection of invertebrates and vertebrates and less attentionhas been given to developing eDNA techniques for detecting aquatic invasive plants. Eurasian watermilfoil (EWM; Myriophyllum spicatum L.) is an invasive species for which improved early detection would be particularly helpful. Advanced

  7. Entrapment of ancient and modern organic carbon by iron on the Eurasian Arctic Shelf

    Science.gov (United States)

    Salvado, Joan A.; Tesi, Tommaso; Semiletov, Igor P.; Dudarev, Oleg V.; Gustafsson, Örjan

    2015-04-01

    Given the potential for climate-carbon feedbacks in the Siberian-Arctic land-ocean system, there is a need for improved understanding of carbon cycle processes (Vonk et al., 2012). The entrapment of organic carbon in sediments is a key factor to attenuate the outgassing of greenhouse gases to the atmosphere. In this context, there is a pressing need to understand the mechanisms that control preservation and accumulations of organic carbon in marine sediments. Recently, the role of iron oxides in the preservation of organic matter globally has been outlined (Lalonde et al., 2012). In the present study, the composition of organic carbon associated to reactive iron (OC-Fe) on the Eurasian Arctic Shelf is evaluated. For this purpose, sediment cores and grab samples were collected in the shelves of the Kara Sea, Laptev Sea and East Siberian Sea from 9 to 69 m water depth. Experiments were conducted to extract the OC-Fe from the sediments by applying a citrate-dithionite iron reduction method -accurately control corrected- and analyze the δ13C, % OC and Δ14C of the bulk and iron-associated fractions. The results show that 11.0 ± 5.5% of organic carbon in surface-sediments of the Siberian Arctic Shelf is attached to reactive iron. The Δ14C and δ13C signatures presented sharply contrasting offsets between the sedimentary bulk and the OC-Fe. The OC-Fe is much younger than the OC-bulk in the eastern East Siberian Sea and older in the Laptev Sea. The same offsets were observed using a dual-carbon endmember mixing model showing that the iron fraction is mainly composed by young marine plankton organic carbon in the eastern East Siberian Sea and pre-aged thawing permafrost in the Laptev Sea. Overall, it seems that (i) some of this pre-aged organic carbon still remains bound to iron oxides after permafrost thawing and (ii) the iron oxides are transferring dissolved organic carbon to the sediment. This study presents the first analyses of Δ14C ever done in the OC

  8. Re-Discussion on Motion of Shanghai VLBI Station Relative to Eurasian Plate From VLBI

    Science.gov (United States)

    Yang, Zhigen; Zhu, Wenyao; Xiong, Yongqing; Zhang, Qiang

    Since 1988, the Shanghai VLBI station, located a Sheshan, in the suburbs of Shanghai, about 30 km away from the downtown, has participated in near 200 international geodetic VLBI experiments which since 1991, have also been the part of content of research project named "The Contemporary Crustal Motion and Geodynamics Project" supported by the Chinese Science and Technology Committee for the major scientific goal of improving the knowledge of the contemporary crustal motions of the Chinese continent, and exploring their possible geodynamical mechanism. In recent years, some results about the horizontal motion of this station relatively to Eurasian plate have been obtained which and are listed in the following Table. No. Horizontal velocity(mm/yr) Local azimuth(degree) Authors 1 16.5+/-1.5 98.7+/- 7.7 Ye and Qian, 1992 2 18.6+/-5.9 114.2+/- 8.5 Ye, Qian et al., 1997 3 7.5+/-1.2 95.2+/-12.1 Qian, 1997 4 8.6 109.0 Ye and Qian, 1997 5 11.1 112.2 Heki, 1996 6 7.7 93.1 SSV(GSFC) 97 R 01 7 18.7 87.3 SSV(GIUB) 97 R 01 8 11.0 61.2 SSV(NOAA) 95 R 01 It can be seen from the Table that the horizontal velocities are between 8-19 mm/yr. However the difference between various values of local azimuth can be as large as 53 degree, i.e. from E 24 degree S to E 29 degree N. Based on the results of No.1-6 in the Table, the motion vector, especially its local azimuth referred to GSFC terrestrial reference frame(TRF), seems relatively stable which toward east-southeast(average value: 11.7+/-4.8 mm/yr, N 103.7+/-9.2 degree E). In this paper, based on the coordinate velocities of ITRF96 which represents a new generation of realization of the International Terrestrial Reference System(ITRS), we re-calculated the velocity vector of Shanghai VLBI station by using the recent calculated rates of baseline length between Shanghai and eight international VLBI stations, including Fairbanks(Gilcreek, Alaska), Wettzell(Germany), Kauai(Hawaii), Minamitorishima(Marcus Island, northwestern Pacific Ocean

  9. In situ morphometric survey elucidates the evolutionary systematics of the Eurasian Himantoglossum clade (Orchidaceae: Orchidinae

    Directory of Open Access Journals (Sweden)

    Richard M. Bateman

    2017-01-01

    Full Text Available Background and Aims The charismatic Himantoglossum s.l. clade of Eurasian orchids contains an unusually large proportion of taxa that are of controversial circumscriptions and considerable conservation concern. Whereas our previously published study addressed the molecular phylogenetics and phylogeography of every named taxon within the clade, here we use detailed morphometric data obtained from the same populations to compare genotypes with associated phenotypes, in order to better explore taxonomic circumscription and character evolution within the clade. Methods Between one and 12 plants found in 25 populations that encompassed the entire distribution of the Himantoglossum s.l. clade were measured in situ for 51 morphological characters. Results for 45 of those characters were subjected to detailed multivariate and univariate analyses. Key Results Multivariate analyses readily separate subgenus Barlia and subgenus Comperia from subgenus Himantoglossum, and also the early-divergent H. formosum from the less divergent remainder of subgenus Himantoglossum. The sequence of divergence of these four lineages is confidently resolved. Our experimental approach to morphometric character analysis demonstrates clearly that phenotypic evolution within Himantoglossum is unusually multi-dimensional. Conclusions Degrees of divergence between taxa shown by morphological analyses approximate those previously shown using molecular analyses. Himantoglossum s.l. is readily divisible into three subgenera. The three sections of subgenus Himantoglossum—hircinum, caprinum and formosum—are arrayed from west to east with only limited geographical overlap. At this taxonomic level, their juxtaposition combines with conflict between contrasting datasets to complicate attempts to distinguish between clinal variation and the discontinuities that by definition separate bona fide species. All taxa achieve allogamy via food deceit and have only weak pollinator specificity

  10. In situ morphometric survey elucidates the evolutionary systematics of the Eurasian Himantoglossum clade (Orchidaceae: Orchidinae)

    Science.gov (United States)

    Molnár V., Attila; Sramkó, Gábor

    2017-01-01

    Background and Aims The charismatic Himantoglossum s.l. clade of Eurasian orchids contains an unusually large proportion of taxa that are of controversial circumscriptions and considerable conservation concern. Whereas our previously published study addressed the molecular phylogenetics and phylogeography of every named taxon within the clade, here we use detailed morphometric data obtained from the same populations to compare genotypes with associated phenotypes, in order to better explore taxonomic circumscription and character evolution within the clade. Methods Between one and 12 plants found in 25 populations that encompassed the entire distribution of the Himantoglossum s.l. clade were measured in situ for 51 morphological characters. Results for 45 of those characters were subjected to detailed multivariate and univariate analyses. Key Results Multivariate analyses readily separate subgenus Barlia and subgenus Comperia from subgenus Himantoglossum, and also the early-divergent H. formosum from the less divergent remainder of subgenus Himantoglossum. The sequence of divergence of these four lineages is confidently resolved. Our experimental approach to morphometric character analysis demonstrates clearly that phenotypic evolution within Himantoglossum is unusually multi-dimensional. Conclusions Degrees of divergence between taxa shown by morphological analyses approximate those previously shown using molecular analyses. Himantoglossum s.l. is readily divisible into three subgenera. The three sections of subgenus Himantoglossum—hircinum, caprinum and formosum—are arrayed from west to east with only limited geographical overlap. At this taxonomic level, their juxtaposition combines with conflict between contrasting datasets to complicate attempts to distinguish between clinal variation and the discontinuities that by definition separate bona fide species. All taxa achieve allogamy via food deceit and have only weak pollinator specificity. Artificial

  11. Non-invasive monitoring of hormones: a tool to improve reproduction in captive breeding of the Eurasian lynx.

    Science.gov (United States)

    Dehnhard, M; Naidenko, S; Frank, A; Braun, B; Göritz, F; Jewgenow, K

    2008-07-01

    The survival of many critical endangered mammal species is often depending on successful captive breeding programmes which include the future option of reintroduction to the wild. Breeding in captivity also demands the application of modern assisted reproductive techniques to ensure maximal biodiversity, but knowledge on reproductive physiology is often limited. Therefore, non-invasive monitoring of urinary and faecal hormones has become an important tool for reproductive management. To exemplify the importance of non-invasive hormone monitoring, we choose the Eurasian lynx as a model for the world's most endangered felid species, the Iberian lynx. We analysed faecal samples of pregnant and pseudo-pregnant female Eurasian lynxes during a 3-year study period. Compared to pre-mating levels faecal progesterone metabolite profiles revealed a tendency towards higher levels in pregnant and pseudo-pregnant females with no difference between both categories. Oestrogen levels raised in both pregnant and pseudo-pregnant females with a tendency to be more elevated and prolonged in pregnant females. Surprisingly both E2 and P4 metabolites were highly correlated (r(2) =0.8131, p Eurasian lynx revealed that the measurement of faecal progesterone metabolites led to profiles dissimilar to profiles shown in other felid species, but similar to those from faecal gestagen metabolite analysis in the Iberian lynx. To identify faecal gestagen and oestrogen metabolites a radio-metabolism study was performed. Using the progesterone immunoassay two major progesterone metabolites were detected demonstrating that the assay indeed tracks the relevant metabolites. The oestrogen assay measured authentic 17beta-oestradiol and oestrone, and their conjugates. The analysis of the faecal metabolite composition in samples from early and late pregnancy and lactation particularly revealed a distinct shift in the relation between 17beta-oestradiol and oestrone that changed in favour of oestrone. This

  12. The Messinian Salinity Crisis: what can we expect from drilling the perched basins from the Balearic Promontory?

    Science.gov (United States)

    Johanna, Lofi; Angelo, Camerlenghi; Agnès, Maillard; Diana, Ochoa

    2015-04-01

    In spite of 40 years of multi-disciplinary research conducted on the Messinian Salinity Crisis (MSC) event, modalities, timing, causes, chronology and consequence at local and planetary scale of this event are still not yet fully understood, and the MSC event remains one of the longest-living controversies in Earth Science. A key factor for the controversy is certainly the lack of a complete record of the MSC deposits preserved in the deepest Mediterranean basins. Anywhere else, on the continental shelves and slopes, the MSC mostly generated a sedimentary/time lag corresponding to a widespread erosional surface. Correlations with the depositional units locally preserved onshore are thus complex, preventing the construction of a coherent scenario linking the outcropping MSC evaporites, the erosion on the margins, and the deposition of clastics and evaporites in the abyssal plains. Recent works based on seismic profile interpretations and conducted on the Balearic promontory allowed to evidence a series of small perched basins presently lying in different water depths stepped from the coast line down to the deep basin. These topographic lows trapped sedimentary series up to 500m thick, interpreted as MSC in age (Maillard et al., 2014; Mocnik et al., 2014; Driussi et al., in press). In the most proximal basins, these deposits have been drilled and logged for industriel purposes and consist of gypsum beds interbedded with marls. Ochoa et al. (submitted) demonstrated that these MSC deposits correlate with the Primary Lower Gypsum sequence deposited in marginal settings before the drawdown phase (Lugli et al., 2010) and that are now observed onshore in tectonically active areas. The basins located in more distal locations also contain MSC deposits (including DREAM proposal) of a Multi-phase IODP Drilling Project entitled "Uncovering A Salt Giant" (857-MDP, coord. A. Camerlenghi). The DREAM Team: A. Giovanni, H. Christian, G. deLangeGert, R. Flecker, D. Garcia

  13. Perch-height specific predation on tropical lizard clay models: implications for habitat selection in mainland neotropical lizards

    Directory of Open Access Journals (Sweden)

    John E Steffen

    2009-09-01

    Full Text Available Predation has been hypothesized to be a strong selective force structuring communities of tropical lizards. Comparisons of perch height and size-based predation frequencies can provide a unique window into understanding how predation might shape habitat selection and morphological patterns in lizards, especially anoles. Here i use plasticine clay models, placed on the trunks of trees and suspended in the canopy to show that predation frequency on clay models differs primarily according to habitat (canopy vs. trunk-ground, but not according to size. These data are discussed in light of observed lizard abundances in the lowland forests of Costa Rica, and are presented as partial explanation for why fewer lizards are found in tree canopies, and more lizards are found on ground-trunk habitats. Rev. Biol. Trop. 57 (3: 859-864. Epub 2009 September 30.Existe la hipótesis de que la depredación es una fuerte fuerza selectiva que estructura las comunidades de lagartijas tropicales. Las comparaciones de las frecuencias de altura de la percha y de depredación con base en el tamaño pueden proveer una ventana única en el entendimiento de cómo la depredación podría moldear la selección del hábitat y los patrones morfológicos en las lagartijas, especialmente anoles. En este estudio uso modelos de plasticina, ubicados en troncos de árboles y suspendidos en el dosel para mostrar que la frecuencia de depredación en los modelos de plasticina difiere primariamente según el hábitat (dosel vs. tronco-suelo pero no según el tamaño. Estos datos se discuten a la luz de las abundancias de lagartijas observadas en los bosques de bajura de Costa Rica, y se presentan como una explicación parcial a porqué menos lagartijas se encuentran en los doseles, y más lagartijas se encuentran en los hábitats suelo-tronco.

  14. Mapping the indentation between the Iberian and Eurasian plates beneath the Western Pyrenees/Eastern Cantabrian Mountains from receiver function analysis

    Science.gov (United States)

    Díaz, J.; Pedreira, D.; Ruiz, M.; Pulgar, J. A.; Gallart, J.

    2012-10-01

    In the last decades, active seismic profiling in the northern part of the Iberian Peninsula has evidenced that the Alpine collision between the Iberian and Eurasian plates resulted in a complex crustal structure, with the Iberian crust underthrusting the Eurasian crust and reaching depths of at least 45-50 km beneath the Pyrenean chain and the Cantabrian Mountains. In the transition between these two zones the situation is particularly complex, as evidenced in previous wide-angle and passive seismic studies. This contribution focuses in getting new clues on the crustal structure of this transitional zone through receiver function (RF) analysis of teleseismic data recorded at permanent and temporary stations located in both the Spanish and French sides of the Western Pyrenees. Different techniques (H-κ stacking, pseudo-migration, synthetic 2D modeling) have been considered in the analysis. Passive seismic data from previous temporary deployments in the zone have been reworked and added to the discussion. A first order result is that passive seismic data are broadly consistent with the indentation of the Iberian and Eurasian crusts inferred from active seismic profiling, thus providing a completely independent confirmation of this feature. For the first time, an Iberian Moho underlying the Eurasian crust is documented from RF beneath the stations located at the Northern side of the Pyrenean range. Moreover, clear indications of dipping interfaces are observed at some stations. The new RF results suggest that in the crustal indentation beneath the Basque Massifs area, the Eurasian crust extends farther south with respect to the image inferred from active seismic data. This new geometry implies that the Pamplona transfer zone has played a major role in the regional geodynamic history.

  15. PKE: tutti ce l’hanno ma pochi lo sanno (far funzionare. Perché un Personal Web non è un Personal Knowledge Environment (PKE

    Directory of Open Access Journals (Sweden)

    Maria Chiara Pettenati

    2013-03-01

    Full Text Available Nel mondo delle tecnologie per la conoscenza è emersa la nuova parola chiave: Personal Web. L’Horizon Report 2009, nel proporre all’attenzione della comunità dell’e-learning questo concetto, ne esalta le potenzialità per la crescita di conoscenza: «la gestione dell’informazione è molto più facile di quanto non lo sia stato prima grazie a strumenti di publishing facili da usare per ogni tipo e forma di contenuti». Il Personal Web rende la gestione dell’informazione «easier than never before», più facile di quanto non sia mai stato, perché per gestire la complessità dell’informazione in rete, tool e servizi di cui disponiamo attraverso il Personal Web rendono semplice lo sviluppo e l’organizzazione del contenuto dinamico online. Armati di strumenti Web per taggare, aggregare, aggiornare e tenere traccia dei contenuti e relazioni i learner di oggi, o i learner per la vita, cioè tutti noi, creano e navigano un Web della Conoscenza. La tesi qui esplorata è che tutti oggi usano un Personal Web ma che pochi se ne sanno avvalere per una efficace gestione della conoscenza: perché per passare dal Personal Web al Personal Knowledge Environment (PKE non bastano pochi click.

  16. Degradation of male and female rufous-and-white wren songs in a tropical forest: effects of sex, perch height, and habitat

    DEFF Research Database (Denmark)

    Barker, Nicole K.S.; Dabelsteen, Torben; Mennill, Daniel J.

    2009-01-01

    We performed a song transmission experiment to investigate the effects of distance, song post height, receiver perch height, signaller sex, and microhabitat on song degradation in rufous-and-white wrens (Thryothorus rufalbus), a neotropical duetting songbird. We quantified the effects of these fa......We performed a song transmission experiment to investigate the effects of distance, song post height, receiver perch height, signaller sex, and microhabitat on song degradation in rufous-and-white wrens (Thryothorus rufalbus), a neotropical duetting songbird. We quantified the effects...... of these factors on excess attenuation, signal-to-noise ratio, tail-to-signal ratio, and blur ratio of male and female songs. As expected, song degradation increased with distance between signaller and receiver. Songs transmitted best when emitted from moderate heights (5-7 m), although this pattern varied....... Rufous-and-white wren songs appeared more attenuated in open field than forest habitats, but microhabitat conditions within the forests exerted a strong influence on song degradation. These findings match previous studies showing an effect of distance, song post height, and habitat, but contrast...

  17. Impact of Salinity on the Incubation Rate and the Performance during the Nursery Phase of Square Head Climbing Perch (Anabas testudineus Bloch, 1792

    Directory of Open Access Journals (Sweden)

    Le, DV.

    2016-01-01

    Full Text Available Square head climbing perch (Anabas testudineus Bloch, 1792 is a high quality fish without small bones. It grows in a wide range of temperatures (10-42 oC, pH (3.5-9.5 and salinity (up to 16%. As regards climate change, this species may become important for aquaculture in the Tam Giang-Cau Hai lagoon near Hue city. To optimise the quality of fingerlings, we analyzed the effect of salinity levels on hatching and nursing in three subsequent experiments. Fertilization, hatching, survival and growth rates for 30 days were determined at salinity levels 0%, 5%, 7%, 13% and 15%. Water temperature and pH varied between 22-29.5 oC and 7.3-7.8, respectively. Between 0-5%, fertilization ratio was 77% to 83% and highest at 5%, but this dropped to 0% when salinity increased; hatching ratio was larger than 90%, but decreased to 0% at 13-15%. Between 0-11%, hatching time of fertilized eggs was not affected by salinity levels. The ratio of deformation gradually increased above 5%. After hatching at either 0 or 5%, survival ratios for square head climbing perch were above 13% up to 5%, but dropped to 0% at 9%. The growth after 30 days of nursing was higher at 5 and 7% compared with that of 0 and 3%.

  18. Artificial perches as a nucleation technique for restoration of a riparian environment: characterization of the seed rain and of natural regeneration

    Directory of Open Access Journals (Sweden)

    Aline Luiza Tomazi

    2010-09-01

    Full Text Available Riparian habitats are important to the maintenance of ecological processes and environmental services. However, a significant portion of the riparian vegetation in the Brazilian Atlantic forest has been removed in response to increasing human pressure. Therefore, the application of restoration techniques in these habitats becomes essential. In this context, a nucleation model with 18 artificial perches was evaluated for the restoration of a degraded riparian area in Gaspar, Santa Catarina, Brazil, by the characterization of the seed rain and natural regeneration. In two years we collected 21,864 seeds of 51 morphospecies, and recorded 42 colonizing species. Zoochoric seeds belonging to 15 plant families comprised 17% of the seed rain and 19.05% of the spontaneously regenerating plant species. Asteraceae and Poaceae were the most represented families. The artificial perches performed the nucleating function through the increase of zoochoric seed rain. However, possibly due to different barriers that were not evaluated in this study, part of these seeds was not recruited. We recommend the application of this technique for the attraction of dispersers in degraded areas similar to the study site.

  19. Artificial perches as a nucleation technique for restoration of a riparian environment: characterization of the seed rain and of natural regeneration.

    Directory of Open Access Journals (Sweden)

    Aline Luiza Tomazi

    2010-01-01

    Full Text Available Riparian habitats are important to the maintenance of ecological processes and environmental services. However, a significant portion of the riparian vegetation in the Brazilian Atlantic forest has been removed in response to increasing human pressure. Therefore, the application of restoration techniques in these habitats becomes essential. In this context, a nucleation model with 18 artificial perches was evaluated for the restoration of a degraded riparian area in Gaspar, Santa Catarina, Brazil, by the characterization of the seed rain and natural regeneration. In two years we collected 21,864 seeds of 51 morphospecies, and recorded 42 colonizing species. Zoochoric seeds belonging to 15 plant families comprised 17% of the seed rain and 19.05% of the spontaneously regenerating plant species. Asteraceae and Poaceae were the most represented families. The artificial perches performed the nucleating function through the increase of zoochoric seed rain. However, possibly due to different barriers that were not evaluated in this study, part of these seeds was not recruited. We recommend the application of this technique for the attraction of dispersers in degraded areas similar to the study site.

  20. Intense infections with a variant of Myxobolus procerus (Myxosporea) in muscle of trout-perch (Percopsis omiscomaycus) in Duluth Harbor, Lake Superior.

    Science.gov (United States)

    Cone, D; Eurell, T; Axler, R; Rau, D; Beasley, V

    1997-01-01

    Intense infections of a variant of Myxobolus procerus (Kudo, 1934) are described from trout-perch (Percopsis omiscomaycus (Walbaum)) collected in Duluth Harbor, Lake Superior, USA. This particular population of parasites has spores that are identical in shape (narrow pyriform) to those described for M. procerus except that they are significantly smaller (13-14.5 microm long versus 15-17 microm long). In contrast to what was originally described for M. procerus, the plasmodia develop primarily within red and white striated muscle fibres and only rarely among the subdermal connective tissue. Most plasmodia were at or near the same stage of development. Typical development involves growth within the fibre. The parasite eventually replaces the entire content of the host cell and appears to halt development before rupturing the outer cell membrane. The only obvious host response was an occasional cyst being invaded by a localized cellular infiltrate. Infected fish appeared of normal health and no grossly evident myoliquefaction was seen. The infections involved several hundred plasmodia per fish and the question of why such unusually high levels of infection would develop in hosts inhabiting a polluted habitat is raised. It is suggested that proliferation of a pollution tolerant oligochaete (the suspected alternate host) in the harbour and/or a compromised host immune system may have increased the probability of successful transmission and development in trout-perch living in the harbour.

  1. EURASIAN MINERAL WATER: MATHEMATICAL MODELING, CLASSIFICATION AND ASSESSMENT OF THEIR IMPACT ON THE BIOCHEMICAL COMPOSITION OF HUMAN BLOOD

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    Nikolay Kornilov

    2014-06-01

    Full Text Available In the article the results of comparative analysis of the composition of the Eurasian hydromineral resources and the assessment of their impact on the physiological condition of a human organism according to biochemical studies of venous blood are presented. Processing of initial data on the composition and properties of mineral waters chloride-hydrocarbonate, sulphate- hydrocarbonate and chloride-sulphate types and venous blood are made using the method of mathematical modeling, developed by the authors of this article. It is shown that in the balneological impact of hydromineral resources on the body in the blood increases the hemoglobin and oxygen, decreases glucose, and acid-base pH shifted to high alkalinity.

  2. New Details of the Eurasian Beaver’s, Castor Fiber (Rodentia, Castoridae, Expansion in the Lowland Part of Transcarpathia, Ukraine

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    Barkasi Z.

    2016-12-01

    Full Text Available The present paper contains information on a new beaver colony discovered in the Chornyi mochar tract, which is located in the lowland part of Transcarpathia (= Zakarpattia Region. This rodent species disappeared from the territory of Transcarpathia most likely in the 18th century. Its first reappearance was recorded in 2003. Since, the Eurasian beaver has demonstrated a rapid expansion, primarily along the main rivers. The discovered by us colony allows to suggest that the beaver is continuing its dispersal, entering far into the main river’s tributaries and other shallower water bodies. Consequently, we are witnessing not only the expansion of the species’ geographical range, but also the enlargement of the number of habitat types occupied by the animal. The possibilities and supposed consequences of the species’ further expansion within the tract are shown as well.

  3. Diet of the Eurasian badger (Meles meles in an area of the Italian Prealps

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    Monica Marassi

    2002-12-01

    Full Text Available Abstract Samples of Eurasian badger faeces (n= 147 were collected at monthly intervals from October 1997 to December 1999 in an area of the Italian Prealps (58 km², on the eastern coast of Lario (Como Lake. The altitude of the area ranged from 200 to 1300 m. Badger scats were analysed to estimate the relative volume and the frequency of occurrence of identifiable food items. Fruits, arthropodes, earthworms and mammals constituted the main food categories. Differences were found between the seasonal frequency of occurrences of arthropodes, earthworms and mammals, considering however that the small sample size in summer does not allow any definitive conclusions. The wide range of food items eaten by badgers and the seasonal differences would suggest that the badger is a "generalist" species which adopts an opportunist feeding strategy.

  4. Desire-state attribution: Benefits of a novel paradigm using the food-sharing behavior of Eurasian jays (Garrulus glandarius).

    Science.gov (United States)

    Ostojić, Ljerka; Cheke, Lucy G; Shaw, Rachael C; Legg, Edward W; Clayton, Nicola S

    2016-01-01

    In recent years, we have investigated the possibility that Eurasian jay food sharing might rely on desire-state attribution. The female's desire for a particular type of food can be decreased by sating her on it (specific satiety) and the food sharing paradigm can be used to test whether the male's sharing pattern reflects the female's current desire. Our previous findings show that the male shares the food that the female currently wants. Here, we consider 3 simpler mechanisms that might explain the male's behavior: behavior reading, lack of self-other differentiation and behavioral rules. We illustrate how we have already addressed these issues and how our food sharing paradigm can be further adapted to answer outstanding questions. The flexibility with which the food sharing paradigm can be applied to rule out alternative mechanisms makes it a useful tool to study desire-state attribution in jays and other species that share food.

  5. Lead levels in Eurasian otters decline with time and reveal interactions between sources, prevailing weather, and stream chemistry.

    Science.gov (United States)

    Chadwick, Elizabeth A; Simpson, Victor R; Nicholls, Abigail E L; Slater, Frederick M

    2011-03-01

    The uptake of contaminants by biota varies spatially and temporally due to a complex range of interacting environmental variables, but such complexities are typically disregarded in studies of temporal change. Here, we use linear modeling to explore spatial and temporal variation in bone Pb levels measured in samples taken from 329 Eurasian otters (Lutra lutra) found dead in southwest England. Between 1992 and 2004 Pb levels in otters fell by 73%, following UK legislative control of Pb emissions implemented since the mid 1980s. Spatial variation in bone Pb was positively correlated with modeled Pb emissions and stream sediment Pb, which interacted negatively with wind-speed and sediment Ca, respectively. Opportunistic collection of samples from wildlife mortalities provided a valuable opportunity for monitoring environmental contamination, interpretation of which was aided by spatially explicit analysis of environmental variables.

  6. Prey availability and diet of the Eurasian otter (Lutra lutra) on a large reservoir and associated tributaries

    Energy Technology Data Exchange (ETDEWEB)

    Sales-Luis, T.; Pedroso, N.M.; Santos-Reis, M. [Lisbon Univ., Lisbon (Portugal). Dept. of Animal Biology

    2007-11-15

    The increase in the construction of large dams over the past 50 years has resulted in a significant change to original river systems with impacts on riparian habitats, fish populations and biological communities in rivers. This study focused on the feeding habits and decline of the Eurasian otter resulting from the construction of large dammed reservoirs. Data presented in this paper was from a research project conducted at the Aguieira reservoir in Portugal in the medium section of the Mondego River and its 6 tributaries. One of the consequences of dam construction is the change in prey communities. It was noted that the otter's foraging ability is restricted in reservoirs because of the steep margins and deep waters. In this study, prey consumption was compared with prey abundance along with diet composition in both the reservoir and associated tributaries. Eurasian otter spraints collected at the Aguieira hydroelectric dam and tributaries were analysed to assess diet compared with prey availability. Fyke and trammel nets were used to evaluate fish and crayfish abundances in the reservoir, while electrofishing was used to estimate prey availability in the tributaries. Fish (primarily Lepomis gibbosus) was the main prey in both the reservoir and its tributaries. The abundance of L. gibbosus in the reservoir and its near absence in the tributaries indicates that otters using the tributaries feed predominantly in the reservoir. Seasonal dietary variations corresponded to increased availability of nonfish prey categories. The study showed that otters do not consume L. gibbosus according to its availability. It was determined that the tributaries provide important otter shelter areas that are scarce at the edge of the reservoir. As such, care should be taken to minimize disturbance in the surrounding catchments to ensure the survival of otter populations. 71 refs., 4 tabs., 4 figs.

  7. Selection of perching site background color by Hamadryas feronia (Lepidoptera: Nymphalidae in Costa Rica: Implications for industrial melanism

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    Luis Ricardo Murillo-Hiller

    2012-09-01

    Full Text Available Observations of the increased frequency of melanic forms in moths of the genus Biston in Great Britain after the industrial revolution lead to the development of the theory of industrial Melanism. Nonetheless, arguments against that interpretation of the experimental evidence have polarized acceptance of the concept. New evidence based on diurnal butterflies is more credible because it involves behavior that can be seen in action, during daylight, and because the natural history of the selected species is well known. An experiment was carried out in which three substrate colors (white, black, and gray were employed to test the landing preferences of Hamadryas feronia. A marked preference was observed for landing on white and gray, and a chi-square (N=644 tests showed evidence of a preference by males to land on white, and for females to land on gray. Black was rejected perhaps because it provides very little background matching with the butterfly’s colors. The butterfly habit of perching selectively on particular color substrates is a genetically fixed behavior, where the males possibly choose white as a tactic to be noticed by females and attract them, whereas females prefer gray to enhance crypsis and avoid attracting predators.Observaciones en el incremento de la frecuencia de las formas melánicas de la polilla Biston de Gran Bretaña después de la revolución industrial, llevó al desarrollo de la teoría del melanismo industrial. Sin embargo, se originaron argumentos en contra de la interpretación experimental de dicho fenómeno que llevaron a polarizar su aceptación general. Nueva evidencia basada en mariposas diurnas genera nuevas perspectivas puesto que incluye el comportamiento, que puede ser apreciado durante el día. Además, la especie seleccionada es bien conocida desde el punto de vista de su historia natural. El experimento que desarrolle consiste en tres sustratos de diferente color (blanco, negro y gris en donde se pone a

  8. Ludvig, Zsuzsa (ed.) Eurasian challenges : partnerships with Russia and other issues of the post-Soviet area. East European Studies, No. 4, Budabest Institute of World Economics and Regional Studies, Hungarian Academy of Sciences, 2013, 163pp. / Csab

    Index Scriptorium Estoniae

    Weiner, Csaba

    2013-01-01

    Arvustus: Ludvig, Zsuzsa (ed.) Eurasian challenges : partnerships with Russia and other issues of the post-Soviet area. Budabest Institute of World Economics and Regional Studies, Hungarian Academy of Sciences, 2013

  9. Presence of the Eurasian lynx (Lynx lynx in three contiguous valleys of the Verbania Province (Piemonte, northern Italy

    Directory of Open Access Journals (Sweden)

    Marco Di Lorenzo

    2000-09-01

    Full Text Available Abstract The presence of the Eurasian lynx (Lynx lynx L. 1758 was revealed during an investigation performed from I991 to 1994 in three contiguous valleys (Antigorio valley, Formazza valley and Devero valley of the Verbania province in Piemonte. In this investigation two methods were employed: interviews with the people who saw a lynx and/or found evidence of its presence (prints, faeces, scratchings on trees and meal remains and field research by means of line transects, as reported by Ragni et al. (1993. The research area was of about 250 km². Lynx signs were obtained in 1991, 1992 and 1994 between 600 and 1800 m a.s.1. and during all seasons. The lynx was usually observed at night and at dusk. The research shows that the Eurasian lynx is present, although sporadically, in this area of the western Italian Alps.

  10. Post-Russian Eurasia and the proto-Eurasian usage of the Runet in Kazakhstan: A plea for a cyberlinguistic turn in area studies

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    Dirk Uffelmann

    2011-07-01

    The paper discusses the role the Russian-based Runet plays for Eurasian webcommunities outside the Russian Federation, mostly relying on Kazakh material, and asks whether post-colonial anxieties about Russian cultural imperialism through the Runet are justified or not and what the Kazakh, possibly post-colonial strategies of coping with this situation are. Essential to this essay is the notion of cyberimperialism, which combines aspects of media studies with post-colonial studies. The interdisciplinary approach to Internet studies is completed by a linguistic focus on the performativity of language usage online for creating situational language identities. The essay rounds off by offering an analysis of Nursultan Nazarbaev’s ambiguous inclusive-exclusive logic of argumentation and confronting it with Russian Eurasianism.

  11. Summer monsoon rainfall variability over North East regions of India and its association with Eurasian snow, Atlantic Sea Surface temperature and Arctic Oscillation

    Science.gov (United States)

    Prabhu, Amita; Oh, Jaiho; Kim, In-won; Kripalani, R. H.; Mitra, A. K.; Pandithurai, G.

    2017-10-01

    This observational study during the 29-year period from 1979 to 2007 evaluates the potential role of Eurasian snow in modulating the North East-Indian Summer Monsoon Rainfall with a lead time of almost 6 months. This link is manifested by the changes in high-latitude atmospheric winter snow variability over Eurasia associated with Arctic Oscillation (AO). Excessive wintertime Eurasian snow leads to an anomalous cooling of the overlying atmosphere and is associated with the negative mode of AO, inducing a meridional wave-train descending over the tropical north Atlantic and is associated with cooling of this region. Once the cold anomalies are established over the tropical Atlantic, it persists up to the following summer leading to an anomalous zonal wave-train further inducing a descending branch over NE-India resulting in weak summer monsoon rainfall.

  12. Association of C-Reactive Protein With Bacterial and Respiratory Syncytial Virus-Associated Pneumonia Among Children Aged <5 Years in the PERCH Study.

    Science.gov (United States)

    Higdon, Melissa M; Le, Tham; O'Brien, Katherine L; Murdoch, David R; Prosperi, Christine; Baggett, Henry C; Brooks, W Abdullah; Feikin, Daniel R; Hammitt, Laura L; Howie, Stephen R C; Kotloff, Karen L; Levine, Orin S; Scott, J Anthony G; Thea, Donald M; Awori, Juliet O; Baillie, Vicky L; Cascio, Stephanie; Chuananon, Somchai; DeLuca, Andrea N; Driscoll, Amanda J; Ebruke, Bernard E; Endtz, Hubert P; Kaewpan, Anek; Kahn, Geoff; Karani, Angela; Karron, Ruth A; Moore, David P; Park, Daniel E; Rahman, Mohammed Ziaur; Salaudeen, Rasheed; Seidenberg, Phil; Somwe, Somwe Wa; Sylla, Mamadou; Tapia, Milagritos D; Zeger, Scott L; Deloria Knoll, Maria; Madhi, Shabir A

    2017-06-15

    Lack of a gold standard for identifying bacterial and viral etiologies of pneumonia has limited evaluation of C-reactive protein (CRP) for identifying bacterial pneumonia. We evaluated the sensitivity and specificity of CRP for identifying bacterial vs respiratory syncytial virus (RSV) pneumonia in the Pneumonia Etiology Research for Child Health (PERCH) multicenter case-control study. We measured serum CRP levels in cases with World Health Organization-defined severe or very severe pneumonia and a subset of community controls. We evaluated the sensitivity and specificity of elevated CRP for "confirmed" bacterial pneumonia (positive blood culture or positive lung aspirate or pleural fluid culture or polymerase chain reaction [PCR]) compared to "RSV pneumonia" (nasopharyngeal/oropharyngeal or induced sputum PCR-positive without confirmed/suspected bacterial pneumonia). Receiver operating characteristic (ROC) curves were constructed to assess the performance of elevated CRP in distinguishing these cases. Among 601 human immunodeficiency virus (HIV)-negative tested controls, 3% had CRP ≥40 mg/L. Among 119 HIV-negative cases with confirmed bacterial pneumonia, 77% had CRP ≥40 mg/L compared with 17% of 556 RSV pneumonia cases. The ROC analysis produced an area under the curve of 0.87, indicating very good discrimination; a cut-point of 37.1 mg/L best discriminated confirmed bacterial pneumonia (sensitivity 77%) from RSV pneumonia (specificity 82%). CRP ≥100 mg/L substantially improved specificity over CRP ≥40 mg/L, though at a loss to sensitivity. Elevated CRP was positively associated with confirmed bacterial pneumonia and negatively associated with RSV pneumonia in PERCH. CRP may be useful for distinguishing bacterial from RSV-associated pneumonia, although its role in discriminating against other respiratory viral-associated pneumonia needs further study.

  13. Presence of the Eurasian lynx (Lynx lynx) in three contiguous valleys of the Verbania Province (Piemonte, northern Italy)

    OpenAIRE

    Marco Di Lorenzo; Luca Ballarini; Radames Bionda; Graziano Favini

    2000-01-01

    Abstract The presence of the Eurasian lynx (Lynx lynx L. 1758) was revealed during an investigation performed from I991 to 1994 in three contiguous valleys (Antigorio valley, Formazza valley and Devero valley) of the Verbania province in Piemonte. In this investigation two methods were employed: interviews with the people who saw a lynx and/or found evidence of its presence (prints, faeces, scratchings on trees and meal remains) and field re...

  14. Validation of an enzyme immunoassay for the measurement of faecal glucocorticoid metabolites in Eurasian (Lynx lynx) and Iberian lynx (Lynx pardinus).

    Science.gov (United States)

    Pribbenow, Susanne; Jewgenow, Katarina; Vargas, Astrid; Serra, Rodrigo; Naidenko, Sergey; Dehnhard, Martin

    2014-09-15

    Stress hormone levels are important indicator of an animal's well-being, as stress has harmful effects on reproduction, growth and immune function. The development of enzyme immunoassays (EIA) to monitor faecal glucocorticoid metabolites (fGM) contributes a powerful tool to assess an animal's adrenal status non-invasively. We aimed to identify a suitable EIA for monitoring fGM by assessing the suitability of six different EIAs for detecting quantitative changes in fGM concentrations in response to an ACTH challenge test in Eurasian lynx. FGM were characterised in a male Eurasian lynx that received an injection of (3)H-cortisol. Using HPLC analyses radiolabeled metabolites were compared with immunoreactive metabolites. The second aim was to biologically validate the established EIA for monitoring adrenocortical activity of captive Iberian lynxes after a translocation to new enclosures in relation to behaviour. Additionally faecal samples of ten pregnant Iberian lynxes from the peripartal period were analysed. The ACTH challenge revealed an 11β-hydroxyetiocholanolone EIA as the most sensitive assay to reflect acute fGM elevations in the Eurasian lynx. HPLC immunograms demonstrated that the 11β-hydroxyetiocholanolone EIA measured significant amounts of immunoreactivities corresponding to radiolabeled metabolites with strong similarities across both lynx species. Additionally, HPLC and GC-MS analyses confirmed the presence of 11β-hydroxyetiocholanolone in faeces of both, the Eurasian and the Iberian lynx. Longitudinal fGM profiles of Iberian lynx revealed increases in concentrations associated with management events. During the peripartal period, however, fGM concentrations were not significantly elevated. Our results show that the 11β-hydroxyetiocholanolone EIA is a reliable tool to assess fGM in both lynx species. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Variation of a carotenoid-based trait in relation to oxidative stress and endocrine status during the breeding season in the Eurasian kestrel: A multi-factorial study

    OpenAIRE

    Casagrande, S.; Dell'Omo, G.; Costantini, D.; Tagliavini, J.; Groothuis, T.

    2011-01-01

    Carotenoid-based skin colorations vary seasonally in many bird species and are thought to be honest sexually selected signals. In order to provide more insight in the potential signal function and underlying mechanisms of such colorations we here quantified patterns of variation of leg coloration in adult male and female Eurasian kestrels (Falco tinnunculus tinnunculus) over the breeding season, and evaluated the relationship between coloration and levels of carotenoids, androgens and estroge...

  16. Impact of Eurasian biomass burning emissions on the springtime lower-tropospheric ozone in North China and the rest of Northeast Asia

    Science.gov (United States)

    Huang, J.; Liu, H.; Crawford, J. H.; Thouret, V.; Rodriguez, J. M.; Strahan, S. E.; Damon, M.; Steenrod, S. D.; Strode, S. A.

    2013-12-01

    Intensive biomass burning activities take place in Eurasia from April through September, severely degrading regional air quality. We examine the impact of Eurasian biomass burning on the springtime (April-May) lower-tropospheric (LT) ozone over Northeast Asia in the Global Modeling Initiative (GMI) chemistry and transport model driven by the Modern Era Retrospective-Analysis for Research and Applications (MERRA) meteorological fields from the NASA Global Modeling and Assimilation Office (GMAO). We evaluate model-simulated ozone against the multi-year (1995-2012) aircraft ozone profiles over Beijing from the Measurement of Ozone and Water Vapor by Airbus In-Service Aircraft (MOZAIC) program and ozonesonde measurements at Japanese stations obtained from the World Ozone and Ultraviolet Radiation Data Centre (WOUDC). The model-simulated large-scale temporal and vertical variability in ozone is similar to that in the MOZAIC observations, but the model often underestimates the magnitude of the observed ozone enhancements in the LT during April-May. By conducting model sensitivity simulations, we quantify and contrast the impacts of Eurasian biomass burning on the springtime LT ozone over Northeast Asia in the years with and without active biomass burning activities, respectively. Extremely high Eurasian biomass burning emissions in combination with stronger northward transport of Chinese anthropogenic emissions resulted in very large ozone enhancements in the LT over Northeast Asia in May 2003. We find that the impact of Eurasian biomass burning emissions on the springtime LT ozone in Beijing can be comparable to, or even higher than that of Chinese anthropogenic emissions. These results have important implications for predicting the air quality of the North China Plain as well as understanding the interannual variability of springtime tropospheric ozone in Northeast Asia.

  17. Structure of the mitochondrial control region of the Eurasian otter (Lutra lutra; Carnivora, Mustelidae): patterns of genetic heterogeneity and implications for conservation of the species in Italy.

    Science.gov (United States)

    Ketmaier, V; Bernardini, C

    2005-01-01

    In this study we determined the complete sequence of the mitochondrial DNA (mtDNA) control region of the Eurasian otter (Lutra lutra). We then compared these new sequences with orthologues of nine carnivores belonging to six families (Mustelidae, Mephitidae, Canidae, Hyaenidae, Ursidae, and Felidae). The comparative analyses identified all the conserved regions previously found in mammals. The Eurasian otter and seven other species have a single location with tandem repeats in the right domain, while the spotted hyena (Hyaenidae) and the tiger (Felidae) have repeated sequences in both the right and left domains. To assess the degree of genetic heterogeneity of the Eurasian otter in Italy we sequenced two fragments of the gene and analyzed length polymorphisms of repeated sequences and heteroplasmy in 32 specimens. The study includes 23 museum specimens collected in northern, central, and southern Italy; most of these specimens are from extinct populations, while the southern Italian samples belong to the sole extant Italian population of the Eurasian otter. The study also includes all the captive-reared animals living in the colony "Centro Lontra, Caramanico Terme" (Pescara, central Italy). The colony is maintained for reintroduction of the species. We found a low level of genetic polymorphism; a single haplotype is dominant, but our data indicate the presence in central and southern Italy of two slightly divergent haplotypes. One haplotype belongs to an extinct population, the other is present in the single extant Italian population. Analyses of length polymorphisms and heteroplasmy indicate that the autochthonous Italian samples are characterized by a distinct array of repeated sequences from captive-reared animals.

  18. The Status of Iraq Smooth-Coated Otter Lutrogale perspicillata maxwelli Hayman 1956 and Eurasian Otter Lutra lutra Linnaeus 1758 in Iraq

    OpenAIRE

    Al-Sheikhly, Omar F.; Iyad A. Nader

    2013-01-01

    Since the 1960s field expeditions, there has been little more knowledge acquired about the mammals of Iraq. There were also no previous surveys dedicated to assessing the status and presence of the two otter species described in Iraq: The Eurasian otter (Lutra lutra) and the Iraq smooth –coated otter (Lutrogale perspicillata maxwelli, an endemic subspecies). Historically, both species thrived among suitable habitats of Iraqi wetlands and were named by Iraqis "Chlaeib Al M'ai" meaning "The wa...

  19. Oxidative stress biomarkers in Eurasian eagle owls (Bubo bubo) in three different scenarios of heavy metal exposure.

    Science.gov (United States)

    Espín, Silvia; Martínez-López, Emma; León-Ortega, Mario; Martínez, José Enrique; García-Fernández, Antonio Juan

    2014-05-01

    The main aim of the present study is the assessment of oxidative stress related to metals in the Eurasian eagle owl (Bubo bubo) from three areas (agricultural and rural area, industrial area, and mining area) of Murcia, Southern Spain. Mean blood metal concentrations were Cd=0.07±0.21, Pb=3.27±5.21, Cu=10.62±4.77, Zn=311.47±67.14, Hg=2.32±3.83 μg/dl wet weight. Although individuals from the mining area had significant higher Pb and Hg concentrations, and significant lower glutathione-S-transferase (GST) and catalase (CAT) activities in red blood cells (RBC); the lack of differences in oxidative damage to membrane lipids (TBARS) among areas suggests that the antioxidant capacity of the different populations is able to deal with oxidant species and maintain TBARS levels in the same amount. Despite the low levels of metals, several oxidative stress biomarkers were correlated with metal concentrations. This study provides threshold concentrations at which metals cause effects on the antioxidant system in Eagle owls. Blood Cd concentrations greater than 0.3 μg/dl produced an inhibition in GPx (32%) and CAT (26%) activity in RBC. However, Cd concentrations higher than 0.02 μg/dl were enough to produce an inhibition of these enzymes. Regarding Pb levels, blood concentrations above 2 μg/dl produced an inhibition of 8% and 10.5% in GPx and CAT activities, respectively, in RBC. A depletion of 16% and 4% in tGSH levels was associated with Pb concentrations higher than 15 and 3 μg/dl, respectively, in individuals from the ancient mine site. In addition, Pb concentrations above 2 and 10 μg/dl produced a TBARS induction of 10% and 28%, respectively, in individuals from both the industrial and the mining area. Finally, Hg concentrations greater than 3 and 10 μg/dl resulted in a TBARS induction of 102% and 190%, respectively, in Eurasian eagle owls from the industrial area. Our findings show that Pb may produce effects on oxidative stress biomarkers in Strigiformes at

  20. Rapid Global River Flood Risk Assessment under Climate and Socioeconomic Scenarios: An Extreme Case of Eurasian region

    Science.gov (United States)

    Kwak, Young-joo; Magome, Jun; Hasegawa, Akira; Iwami, Yoichi

    2017-04-01

    Causing widespread devastation with massive economic damage and loss of human lives, flood disasters hamper economic growth and accelerate poverty particularly in developing countries. Globally, this trend will likely continue due to increase in flood magnitude and lack of preparedness for extreme events. In line with risk reduction efforts since the early 21st century, the monitors and governors of global river floods should pay attention to international scientific and policy communities for support to facilitate evidence-based policy making with a special interest in long-term changes due to climate change and socio-economic effects. Although advanced hydrological inundation models and risk models have been developed to reveal flood risk, hazard, exposure, and vulnerability at a river basin, it is obviously hard to identify the distribution and locations of continent-level flood risk based on national-level data. Therefore, we propose a methodological possibility for rapid global flood risk assessment with the results from its application to the two periods, i.e., Present (from 1980 to 2004) and Future (from 2075 to 2099). The method is particularly designed to effectively simplify complexities of a hazard area by calculating the differential inundation depth using GFID2M (global flood inundation depth 2-dimension model), despite low data availability. In this research, we addressed the question of which parts in the Eurasian region (8E to 180E, 0N to 60N) can be found as high-risk areas in terms of exposed population and economy in case of a 50-year return period flood. Economic losses were estimated according to the Shared Socioeconomic Pathways (SSP) scenario, and the flood scale was defined using the annual maximum daily river discharge under the extreme conditions of climate change simulated with MRI-AGCM3.2S based on the Representative Concentration Pathways (RCP8.5) emissions scenario. As a preliminary result, the total potential economic loss in the

  1. Effects of temperature and grazing on soil organic carbon storage in grasslands along the Eurasian steppe eastern transect.

    Science.gov (United States)

    Zhao, Yanyun; Ding, Yong; Hou, Xiangyang; Li, Frank Yonghong; Han, Wenjun; Yun, Xiangjun

    2017-01-01

    Soil represents the largest terrestrial organic carbon pool. To address global climate change, it is essential to explore the soil organic carbon storage patterns and their controlling factors. We investigated the soil organic carbon density (SOCD) in 48 grassland sites along the Eurasian steppe eastern transect (ESET) region, which covers the Inner Mongolia grassland subregion and Mongolia grasslands subregion. Specifically, we analyzed the SOCD in the top 30 cm soil layer and its relationships with climatic variables, soil texture, grazing intensity and community biomass productivity. The results showed that the average SOCD of the ESET was 4.74 kg/m2, and the SOCD of the Inner Mongolia grassland subregion (4.11 kg/m2) was significantly lower than that of the Mongolia grassland subregion (5.79 kg/m2). Significant negative relationships were found between the SOCD and the mean annual temperature (MAT), mean annual precipitation (MAP) and grazing intensity in the ESET region. The MAT and grazing intensity were identified as the major factors influencing the SOCD in the ESET region; the MAP and MAT were the major factors influencing the SOCD in the Inner Mongolia grassland subregion; and the MAT and soil pH were the major factors influencing the SOCD in the Mongolia grassland subregion.

  2. Effects of temperature and grazing on soil organic carbon storage in grasslands along the Eurasian steppe eastern transect.

    Directory of Open Access Journals (Sweden)

    Yanyun Zhao

    Full Text Available Soil represents the largest terrestrial organic carbon pool. To address global climate change, it is essential to explore the soil organic carbon storage patterns and their controlling factors. We investigated the soil organic carbon density (SOCD in 48 grassland sites along the Eurasian steppe eastern transect (ESET region, which covers the Inner Mongolia grassland subregion and Mongolia grasslands subregion. Specifically, we analyzed the SOCD in the top 30 cm soil layer and its relationships with climatic variables, soil texture, grazing intensity and community biomass productivity. The results showed that the average SOCD of the ESET was 4.74 kg/m2, and the SOCD of the Inner Mongolia grassland subregion (4.11 kg/m2 was significantly lower than that of the Mongolia grassland subregion (5.79 kg/m2. Significant negative relationships were found between the SOCD and the mean annual temperature (MAT, mean annual precipitation (MAP and grazing intensity in the ESET region. The MAT and grazing intensity were identified as the major factors influencing the SOCD in the ESET region; the MAP and MAT were the major factors influencing the SOCD in the Inner Mongolia grassland subregion; and the MAT and soil pH were the major factors influencing the SOCD in the Mongolia grassland subregion.

  3. Sustainably Harvesting a Large Carnivore? Development of Eurasian Lynx Populations in Norway During 160 Years of Shifting Policy

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    Linnell, John D. C.; Broseth, Henrik; Odden, John; Nilsen, Erlend Birkeland

    2010-05-01

    The management of large carnivores in multiuse landscapes is always controversial, and managers need to balance a wide range of competing interests. Hunter harvest is often used to limit population size and distribution but is proving to be both controversialand technically challenging. Eurasian lynx ( Lynx lynx) are currently managed as a game species in Norway. We describe an adaptive management approach where quota setting is based on an annual census and chart the population development through the period 1996-2008, as management has become significantly more sophisticated and better informed by the increased availability of scientific data. During this period the population has been through a period of high quotas and population decline caused by fragmented management authority and overoptimistic estimates of lynx reproduction, followed by a period of recovery due to quota reductions. The modern management regime is placed in the context of shifting policy during the last 160 years, during which management goals have moved from extermination stimulated by bounties, through a short phase of protection, and now to quota-regulated harvest. Much management authority has also been delegated from central to local levels. We conclude that adaptive management has the potential to keep the population within some bounded limits, although there will inevitably be fluctuation.

  4. Feather content of porphyrins in Eurasian eagle owl (Bubo bubo) fledglings depends on body condition and breeding site quality.

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    Galván, Ismael; Del Mar Delgado, María; Camarero, Pablo R; Mateo, Rafael; Lourenço, Rui; Penteriani, Vincenzo

    2018-02-13

    Porphyrins are pigments produced in most animal cells during the synthesis of heme, but their importance for external coloration is unclear. Owls (Order Strigiformes) are among the few animals that accumulate porphyrins in the integument, where it could serve as a means of signaling. Here we hypothesized that the porphyrin content of feathers may depend on body condition and breeding site quality in Eurasian eagle owl (Bubo bubo) fledglings and thus constitute amplifiers of the quality of the area where they are born. Using high-performance liquid chromatography (HPLC), we found two porphyrins (protoporphyrin IX and coproporphyrin III) in the body feathers of 19 eagle owl fledglings from seven breeding territories. Coproporphyrin III, but not protoporphyrin IX feather concentration, was positively associated with the body mass of fledglings and with the quality of the breeding sites where they were reared with respect to food quality and availability. As coproporphyrin III is produced under oxidative stress, we suggest that good breeding sites may lead to fledglings in good condition. This in turn may make fledglings induce certain level of free radical and coproporphyrin III production to signal to conspecifics their site-mediated capacity to cope with oxidative stress. This is the first time that porphyrin content in the integument has been found to be related to individual quality, opening a new scenario for studying evolution of animal coloration. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  5. Intrageneric diversity of the cytochrome B gene and phylogeny of eurasian species of the genus mustela (mustelidae, carnivora).

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    Kurose, N; Abramov, A V; Masuda, R

    2000-07-01

    To illuminate molecular phylogenetic relationships among Eurasian species of the genus Mustela (Mustelidae, Carnivora), we determined nucleotide sequences of the complete mitochondrial cytochrome b gene region (1,140 base pairs). Molecular phylogenetic trees, constructed using the neighbor-joining and the maximum likelihood methods, showed the common topology of species relationships to each other. The American mink M. vison first branched off and was positioned very remotely from the other species of Mustela. Excluding M. vison, the ermine M. erminea first split from the rest of the species. Two small body-sized weasels, the least weasel M. nivalis and the mountain weasel M. altaica, comprised one cluster (named "the small weasel group"). The other species formed another cluster, where the remarkably close relationships among the domestic ferret M. furo, the European polecat M. putorius, and the steppe polecat M. eversmanni were noticed with 87-94% bootstrap values (named "the ferret group"), supporting the history that the ferret was domesticated from M. putorius and/or M. eversmanni. The European mink M. lutreola was the closest to the ferret group. The genetic distance between the Siberian weasel M. sibirica and the Japanese weasel M. itatsi corresponded to differences of interspecific level, while the two species were relatively close to M. lutreola and the ferret group. These results provide invaluable insight for understanding the evolution of Mustela as well as for investigating the hybridization status between native and introduced species for conservation.

  6. The Eurasian eagle-owl (Bubo bubo diet in the Trøndelag region (Central Norway

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    Obuch Ján

    2016-12-01

    Full Text Available Between 2008 and 2015 we collected pellets of the Eurasian eagle-owl (Bubo bubo in the Trøndelag region of central Norway and identified the food remains in these samples. We collected material at 45 sites with samples from a total of 76 nests. Some of the samples were from older and already abandoned nests, but at several sites we also found and collected fresh B. bubo pellets. In total 40,766 items of prey were identified from the osteological material. The most dominant food components were mammals (Mammalia, 25 species, 63.5%. The species representation of birds was very diverse (Aves, more than 150 species, 19.4%. Of amphibians (Amphibia, 1 6.8%, the well-represented species were Rana temporaria. Fish (Pisces, 0.3% were represented rarely, while invertebrates were represented only sporadically (Invertebrata, 0.05%. A special composition was found in the diet spectra of the mammals and birds in the mountainous areas at altitudes between 220-780 m above sea level. The highest proportion of frogs was found in areas in the proximity of the mainland shore. On the northern islands located near the coast a significant proportion of the B. bubo diet consisted of rodents (Rodentia. On the more isolated southern islands of Frøya, Hitra and Storfosna the main prey was sea birds, and of the mammals there were also hedgehogs and rats.

  7. Effect of incubation on bacterial communities of eggshells in a temperate bird, the Eurasian Magpie (Pica pica.

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    Won Young Lee

    Full Text Available Inhibitory effect of incubation on microbial growth has extensively been studied in wild bird populations using culture-based methods and conflicting results exist on whether incubation selectively affects the growth of microbes on the egg surface. In this study, we employed culture-independent methods, quantitative PCR and 16S rRNA gene pyrosequencing, to elucidate the effect of incubation on the bacterial abundance and bacterial community composition on the eggshells of the Eurasian Magpie (Pica pica. We found that total bacterial abundance increased and diversity decreased on incubated eggs while there were no changes on non-incubated eggs. Interestingly, Gram-positive Bacillus, which include mostly harmless species, became dominant and genus Pseudomonas, which include opportunistic avian egg pathogens, were significantly reduced after incubation. These results suggest that avian incubation in temperate regions may promote the growth of harmless (or benevolent bacteria and suppress the growth of pathogenic bacterial taxa and consequently reduce the diversity of microbes on the egg surface. We hypothesize that this may occur due to difference in sensitivity to dehydration on the egg surface among microbes, combined with the introduction of Bacillus from bird feathers and due to the presence of antibiotics that certain bacteria produce.

  8. Progress in Oral Vaccination against Tuberculosis in Its Main Wildlife Reservoir in Iberia, the Eurasian Wild Boar

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    Beatriz Beltrán-Beck

    2012-01-01

    Full Text Available Eurasian wild boar (Sus scrofa is the main wildlife reservoir for tuberculosis (TB in Iberia. This review summarizes the current knowledge on wild boar vaccination including aspects of bait design, delivery and field deployment success; wild boar response to vaccination with Bacillus Calmette-Guérin (BCG and inactivated Mycobacterium bovis; and wild boar vaccination biosafety issues as well as prospects on future research. Oral vaccination with BCG in captive wild boar has shown to be safe with significant levels of protection against challenge with virulent M. bovis. An oral vaccination with a new heat-killed M. bovis vaccine conferred a protection similar to BCG. The study of host-pathogen interactions identified biomarkers of resistance/susceptibility to tuberculosis in wild boar such as complement component 3 (C3 and methylmalonyl coenzyme A mutase (MUT that were used for vaccine development. Finally, specific delivery systems were developed for bait-containing vaccines to target different age groups. Ongoing research includes laboratory experiments combining live and heat-killed vaccines and the first field trial for TB control in wild boar.

  9. Similar estimates of population genetic composition and sex ratio derived from carcasses and faeces of Eurasian otter Lutra lutra.

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    Dallas, John F; Coxon, Karen E; Sykes, Tim; Chanin, Paul R F; Marshall, Freda; Carss, David N; Bacon, Philip J; Piertney, Stuart B; Racey, Paul A

    2003-01-01

    Collecting faeces is viewed as a potentially efficient way to sample elusive animals. Nonetheless, any biases in estimates of population composition associated with such sampling remain uncharacterized. The goal of this study was to compare estimates of genetic composition and sex ratio derived from Eurasian otter Lutra lutra spraints (faeces) with estimates derived from carcasses. Twenty per cent of 426 wild-collected spraints from SW England yielded composite genotypes for 7-9 microsatellites and the SRY gene. The expected number of incorrect spraint genotypes was negligible, given the proportions of allele dropout and false allele detection estimated using paired blood and spraint samples of three captive otters. Fifty-two different spraint genotypes were detected and compared with genotypes of 70 otter carcasses from the same area. Carcass and spraint genotypes did not differ significantly in mean number of alleles, mean unbiased heterozygosity or sex ratio, although statistical power to detect all but large differences in sex ratio was low. The genetic compositions of carcass and spraint genotypes were very similar according to confidence intervals of theta and two methods for assigning composite genotypes to groups. A distinct group of approximately 11 carcass and spraint genotypes was detected using the latter methods. The results suggest that spraints can yield unbiased estimates of population genetic composition and sex ratio.

  10. Age-related changes in somatic condition and reproduction in the Eurasian beaver: Resource history influences onset of reproductive senescence.

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    Ruairidh D Campbell

    Full Text Available Using 15 years of data from a stable population of wild Eurasian beavers (Castor fiber, we examine how annual and lifetime access to food resources affect individual age-related changes in reproduction and somatic condition. We found an age-related decline in annual maternal reproductive output, after a peak at age 5-6. Rainfall, an established negative proxy of annual resource availability for beavers, was consistently associated with lower reproductive output for females of all ages. In contrast, breeding territory quality, as a measure of local resource history over reproductive lifetimes, caused differences in individual patterns of reproductive senescence; animals from lower quality territories senesced when younger. Litter size was unrelated to maternal age, although adult body weight increased with age. In terms of resource effects, in poorer years but not in better years, older mothers produced larger offspring than did younger mothers, giving support to the constraint theory. Overall, our findings exemplify state-dependent life-history strategies, supporting an effect of resources on reproductive senescence, where cumulative differences in resource access, and not just reproductive strategy, mediate long-term reproductive trade-offs, consistent with the disposable soma and reproductive restraint theories. We propose that flexible life-history schedules could play a role in the dynamics of populations exhibiting reproductive skew, with earlier breeding opportunities leading to an earlier senescence schedule through resource dependent mechanisms.

  11. A western Eurasian male is found in 2000-year-old elite Xiongnu cemetery in Northeast Mongolia.

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    Kim, Kijeong; Brenner, Charles H; Mair, Victor H; Lee, Kwang-Ho; Kim, Jae-Hyun; Gelegdorj, Eregzen; Batbold, Natsag; Song, Yi-Chung; Yun, Hyeung-Won; Chang, Eun-Jeong; Lkhagvasuren, Gavaachimed; Bazarragchaa, Munkhtsetseg; Park, Ae-Ja; Lim, Inja; Hong, Yun-Pyo; Kim, Wonyong; Chung, Sang-In; Kim, Dae-Jin; Chung, Yoon-Hee; Kim, Sung-Su; Lee, Won-Bok; Kim, Kyung-Yong

    2010-07-01

    We analyzed mitochondrial DNA (mtDNA), Y-chromosome single nucleotide polymorphisms (Y-SNP), and autosomal short tandem repeats (STR) of three skeletons found in a 2,000-year-old Xiongnu elite cemetery in Duurlig Nars of Northeast Mongolia. This study is one of the first reports of the detailed genetic analysis of ancient human remains using the three types of genetic markers. The DNA analyses revealed that one subject was an ancient male skeleton with maternal U2e1 and paternal R1a1 haplogroups. This is the first genetic evidence that a male of distinctive Indo-European lineages (R1a1) was present in the Xiongnu of Mongolia. This might indicate an Indo-European migration into Northeast Asia 2,000 years ago. Other specimens are a female with mtDNA haplogroup D4 and a male with Y-SNP haplogroup C3 and mtDNA haplogroup D4. Those haplogroups are common in Northeast Asia. There was no close kinship among them. The genetic evidence of U2e1 and R1a1 may help to clarify the migration patterns of Indo-Europeans and ancient East-West contacts of the Xiongnu Empire. Artifacts in the tombs suggested that the Xiongnu had a system of the social stratification. The West Eurasian male might show the racial tolerance of the Xiongnu Empire and some insight into the Xiongnu society. (c) 2010 Wiley-Liss, Inc.

  12. The Eurasian ice sheet reinforces the East Asian summer monsoon during the interglacial 500 000 years ago

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    Qiuzhen Yin

    2008-05-01

    Full Text Available Deep-sea and ice-core records show that interglacial periods were overall less "warm" before about 420 000 years ago than after, with relatively higher ice volume and lower greenhouse gases concentration. This is particularly the case for the interglacial Marine Isotope Stage 13 which occurred about 500 000 years ago. However, by contrast, the loess and other proxy records from China suggest an exceptionally active East Asian summer monsoon during this interglacial. A three-dimension Earth system Model of Intermediate complexity was used to understand this seeming paradox. The astronomical forcing and the remnant ice sheets present in Eurasia and North America were taken into account in a series of sensitivity experiments. Expectedly, the seasonal contrast is larger and the East Asian summer monsoon is reinforced compared to Pre-Industrial time when Northern Hemisphere summer is at perihelion. Surprisingly, the presence of the Eurasian ice sheet was found to reinforce monsoon, too, through a south-eastwards perturbation planetary wave. The trajectory of this wave is influenced by the Tibetan plateau.

  13. Novel reassortment of Eurasian avian-like and pandemic/2009 influenza viruses in swine: infectious potential for humans.

    Science.gov (United States)

    Zhu, Huachen; Zhou, Boping; Fan, Xiaohui; Lam, Tommy T Y; Wang, Jia; Chen, Antony; Chen, Xinchun; Chen, Honglin; Webster, Robert G; Webby, Richard; Peiris, Joseph S M; Smith, David K; Guan, Yi

    2011-10-01

    Pigs are considered to be intermediate hosts and "mixing vessels," facilitating the genesis of pandemic influenza viruses, as demonstrated by the emergence of the 2009 H1N1 pandemic (pdm/09) virus. The prevalence and repeated introduction of the pdm/09 virus into pigs raises the possibility of generating novel swine influenza viruses with the potential to infect humans. To address this, an active influenza surveillance program was conducted with slaughtered pigs in abattoirs in southern China. Over 50% of the pigs tested were found to be seropositive for one or more H1 influenza viruses, most commonly pdm/09-like viruses. Out of 36 virus isolates detected, one group of novel reassortants had Eurasian avian-like swine H1N1 surface genes and pdm/09 internal genes. Animal experiments showed that this virus transmitted effectively from pig to pig and from pig to ferret, and it could also replicate in ex vivo human lung tissue. Immunization against the 2009 pandemic virus gave only partial protection to ferrets. The continuing prevalence of the pdm/09 virus in pigs could lead to the genesis of novel swine reassortant viruses with the potential to infect humans.

  14. Metabolism of prostaglandin F2alpha in Eurasian lynx (Lynx lynx) and Asian leopard cat (Prionailurus bengalensis euptilura).

    Science.gov (United States)

    Dehnhard, M; Naidenko, S V; Jewgenow, K

    2017-04-01

    Methods for monitoring endocrine status are useful tools for reproduction management. In particular, successful captive breeding of endangered feline species requires reliable methods for pregnancy diagnosis. In many species, uterine and placental prostaglandin-F2α (PGF2α) is involved in the regulation of reproductive processes. PGF2α is metabolized to 13,14-dihydro-15-keto-PGF2a (PGFM) during the first passage through the lungs. Immunoreactive PGFM is elevated in pregnant felids during the last trimester and is used for pregnancy diagnosis, although authentic PGFM is excreted in negligible amounts. To investigate the metabolism of PGF2α, a radiometabolism study was performed in two individuals of two feline species, Eurasian lynx and leopard cats, by injection of tritiated PGF2α and collection of faecal and urinary samples. All samples were extracted and subjected to HPLC separation. Radioactivity and immunoreactivity towards PGFM were determined in each HPLC fraction. The radio- and immunogramms differ slightly between the two species, and radiolabelled PGFM was present only in minor amounts. One major eicosanoid metabolite was found in all urine and faecal samples analysed, and also in previous studies in faecal samples of several pregnant feline species. Its polarity was similar, but not identical to PGF2α. We hypothesized that PGF2α is metabolized to more polar dinor and tetranor metabolites. First mass spectrometric analyses favoured a dinor metabolite as major compound of PGF2α metabolism in felids. Following identification and validation in the studied species, we aim to use these metabolites to improve pregnancy detection in other felids and probably other carnivores. © 2017 Blackwell Verlag GmbH.

  15. Eurasian jays do not copy the choices of conspecifics, but they do show evidence of stimulus enhancement

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    Rachael Miller

    2016-12-01

    Full Text Available Corvids (birds in the crow family are hypothesised to have a general cognitive tool-kit because they show a wide range of transferrable skills across social, physical and temporal tasks, despite differences in socioecology. However, it is unknown whether relatively asocial corvids differ from social corvids in their use of social information in the context of copying the choices of others, because only one such test has been conducted in a relatively asocial corvid. We investigated whether relatively asocial Eurasian jays (Garrulus glandarius use social information (i.e., information made available by others. Previous studies have indicated that jays attend to social context in their caching and mate provisioning behaviour; however, it is unknown whether jays copy the choices of others. We tested the jays in two different tasks varying in difficulty, where social corvid species have demonstrated social information use in both tasks. Firstly, an object-dropping task was conducted requiring objects to be dropped down a tube to release a food reward from a collapsible platform, which corvids can learn through explicit training. Only one rook and one New Caledonian crow have learned the task using social information from a demonstrator. Secondly, we tested the birds on a simple colour discrimination task, which should be easy to solve, because it has been shown that corvids can make colour discriminations. Using the same colour discrimination task in a previous study, all common ravens and carrion crows copied the demonstrator. After observing a conspecific demonstrator, none of the jays solved the object-dropping task, though all jays were subsequently able to learn to solve the task in a non-social situation through explicit training, and jays chose the demonstrated colour at chance levels. Our results suggest that social and relatively asocial corvids differ in social information use, indicating that relatively asocial species may have

  16. Evolution of an Eurasian avian-like influenza virus in naïve and vaccinated pigs.

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    Pablo R Murcia

    Full Text Available Influenza viruses are characterized by an ability to cross species boundaries and evade host immunity, sometimes with devastating consequences. The 2009 pandemic of H1N1 influenza A virus highlights the importance of pigs in influenza emergence, particularly as intermediate hosts by which avian viruses adapt to mammals before emerging in humans. Although segment reassortment has commonly been associated with influenza emergence, an expanded host-range is also likely to be associated with the accumulation of specific beneficial point mutations. To better understand the mechanisms that shape the genetic diversity of avian-like viruses in pigs, we studied the evolutionary dynamics of an Eurasian Avian-like swine influenza virus (EA-SIV in naïve and vaccinated pigs linked by natural transmission. We analyzed multiple clones of the hemagglutinin 1 (HA1 gene derived from consecutive daily viral populations. Strikingly, we observed both transient and fixed changes in the consensus sequence along the transmission chain. Hence, the mutational spectrum of intra-host EA-SIV populations is highly dynamic and allele fixation can occur with extreme rapidity. In addition, mutations that could potentially alter host-range and antigenicity were transmitted between animals and mixed infections were commonplace, even in vaccinated pigs. Finally, we repeatedly detected distinct stop codons in virus samples from co-housed pigs, suggesting that they persisted within hosts and were transmitted among them. This implies that mutations that reduce viral fitness in one host, but which could lead to fitness benefits in a novel host, can circulate at low frequencies.

  17. Partial least regression approach to forecast the East Asian winter monsoon using Eurasian snow cover and sea surface temperature

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    Yu, Lulu; Wu, Zhiwei; Zhang, Renhe; Yang, Xin

    2017-06-01

    Seasonal prediction of the East Asian (EA) winter monsoon (EAWM) is of great significance yet a challenging issue. In this study, three statistical seasonal prediction models for the EAWM are established using three leading modes of the Eurasian snow cover (ESC), the first leading mode of sea surface temperature (SST) and the four leading modes of the combination of the ESC and SST in preceding autumn, respectively. These leading modes are identified by the partial-least square (PLS) regression. The first PLS (PLS1) mode for the ESC features significantly anomalous snow cover in Siberia and Tibetan Plateau regions. The ESC second PLS (PLS2) mode corresponds to large areas of snow cover anomalies in the central Siberia, whereas the third PLS (PLS3) mode a meridional seesaw pattern of ESC. The SST PLS1 mode basically exhibits an El Niño-Southern Oscillation developing phase in equatorial eastern Pacific and significant SST anomalies in North Atlantic. A strong EAWM tends to emerge in a La Niña year concurrent with cold SST anomalies in the North Atlantic, and vice versa. After a 35-year training period (1967-2001), three PLS seasonal prediction models are constructed and the 11-year hindcast is performed for the period of 2002-2012, respectively. The PLS model based on combination of the autumn ESC and SST exhibits the best hindcast skill among the three models, its correlation coefficient between the observation and the hindcast reaching 0.86. This indicates that this physical-based PLS model may provide another practical tool for the EAWM. In addition, the relative contribution of the ESC and SST is also examined by assessing the hindcast skills of the other two PLS models constructed solely by the ESC or SST. Possible physical mechanisms are also discussed.

  18. A physical-empirical model of the East Asian winter monsoon using Eurasian snow cover and sea surface temperature

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    Yu, Lulu; Wu, Zhiwei; Zhang, Renhe

    2017-04-01

    Seasonal prediction of the East Asian (EA) winter monsoon (EAWM) is of great significance yet a challenging issue. In this study, three physical-empirical (PE) seasonal prediction models for the EAWM are established using three leading modes of the Eurasian snow cover (ESC