WorldWideScience

Sample records for beds habitat selection

  1. Restoring lakes by using artificial plant beds: habitat selection of zooplankton in a clear and a turbid shallow lake

    DEFF Research Database (Denmark)

    Schou, Majbritt Overgård; Risholt, Casper; Lauridsen, Torben L.;

    2009-01-01

    1. Return of large-bodied zooplankton populations is of key importance for creating a shift from a turbid to a clear-water state in shallow lakes after a nutrient loading reduction. In temperate lakes, recovery is promoted by submerged macrophytes which function as a daytime refuge for large...... in lake restoration, we followed the day–night habitat choices of zooplankton throughout summer in a clear and a turbid lake. Observations were made in the pelagic and littoral zones and in APB in the littoral representing three different plant densities (coverage 0%, 40% and 80%). 3. In the clear lake...... overall more equally distributed between the five habitats. Ceriodaphnia was proportionally more abundant in the APB during most of the season. Cyclopoids were more abundant in the high APB during day but were equally distributed between the five habitats during night. 4. In the turbid lake, however...

  2. Habitat selection by emperor fish larvae

    OpenAIRE

    Nakamura, Y; Shibuno, T.; Lecchini, David; Watanabe, Y.

    2009-01-01

    One of the great puzzles of coral reef fish ecology is how pelagic larvae locate the habitat in which they settle. The present study explored whether offshore emperor fish (Lethrinidae) larvae selected a specific reef and/or habitat at settlement. Although older juveniles are known to use back-reef seagrass beds as a potential nursery habitat, information is scarce regarding pre-settlement larvae. Using light traps anchored on the reef slopes at seagrass-replete and seagrass-free reefs (lshig...

  3. Habitat Use and Selection by Giant Pandas

    Science.gov (United States)

    Hull, Vanessa; Zhang, Jindong; Huang, Jinyan; Zhou, Shiqiang; Viña, Andrés; Shortridge, Ashton; Li, Rengui; Liu, Dian; Xu, Weihua; Ouyang, Zhiyun; Zhang, Hemin; Liu, Jianguo

    2016-01-01

    Animals make choices about where to spend their time in complex and dynamic landscapes, choices that reveal information about their biology that in turn can be used to guide their conservation. Using GPS collars, we conducted a novel individual-based analysis of habitat use and selection by the elusive and endangered giant pandas (Ailuropoda melanoleuca). We constructed spatial autoregressive resource utilization functions (RUF) to model the relationship between the pandas' utilization distributions and various habitat characteristics over a continuous space across seasons. Results reveal several new insights, including use of a broader range of habitat characteristics than previously understood for the species, particularly steep slopes and non-forest areas. We also used compositional analysis to analyze habitat selection (use with respect to availability of habitat types) at two selection levels. Pandas selected against low terrain position and against the highest clumped forest at the at-home range level, but no significant factors were identified at the within-home range level. Our results have implications for modeling and managing the habitat of this endangered species by illustrating how individual pandas relate to habitat and make choices that differ from assumptions made in broad scale models. Our study also highlights the value of using a spatial autoregressive RUF approach on animal species for which a complete picture of individual-level habitat use and selection across space is otherwise lacking. PMID:27627805

  4. Habitat Use and Selection by Giant Pandas.

    Science.gov (United States)

    Hull, Vanessa; Zhang, Jindong; Huang, Jinyan; Zhou, Shiqiang; Viña, Andrés; Shortridge, Ashton; Li, Rengui; Liu, Dian; Xu, Weihua; Ouyang, Zhiyun; Zhang, Hemin; Liu, Jianguo

    2016-01-01

    Animals make choices about where to spend their time in complex and dynamic landscapes, choices that reveal information about their biology that in turn can be used to guide their conservation. Using GPS collars, we conducted a novel individual-based analysis of habitat use and selection by the elusive and endangered giant pandas (Ailuropoda melanoleuca). We constructed spatial autoregressive resource utilization functions (RUF) to model the relationship between the pandas' utilization distributions and various habitat characteristics over a continuous space across seasons. Results reveal several new insights, including use of a broader range of habitat characteristics than previously understood for the species, particularly steep slopes and non-forest areas. We also used compositional analysis to analyze habitat selection (use with respect to availability of habitat types) at two selection levels. Pandas selected against low terrain position and against the highest clumped forest at the at-home range level, but no significant factors were identified at the within-home range level. Our results have implications for modeling and managing the habitat of this endangered species by illustrating how individual pandas relate to habitat and make choices that differ from assumptions made in broad scale models. Our study also highlights the value of using a spatial autoregressive RUF approach on animal species for which a complete picture of individual-level habitat use and selection across space is otherwise lacking. PMID:27627805

  5. Does learning or instinct shape habitat selection?

    Science.gov (United States)

    Nielsen, Scott E; Shafer, Aaron B A; Boyce, Mark S; Stenhouse, Gordon B

    2013-01-01

    Habitat selection is an important behavioural process widely studied for its population-level effects. Models of habitat selection are, however, often fit without a mechanistic consideration. Here, we investigated whether patterns in habitat selection result from instinct or learning for a population of grizzly bears (Ursus arctos) in Alberta, Canada. We found that habitat selection and relatedness were positively correlated in female bears during the fall season, with a trend in the spring, but not during any season for males. This suggests that habitat selection is a learned behaviour because males do not participate in parental care: a genetically predetermined behaviour (instinct) would have resulted in habitat selection and relatedness correlations for both sexes. Geographic distance and home range overlap among animals did not alter correlations indicating that dispersal and spatial autocorrelation had little effect on the observed trends. These results suggest that habitat selection in grizzly bears are partly learned from their mothers, which could have implications for the translocation of wildlife to novel environments.

  6. Does learning or instinct shape habitat selection?

    Directory of Open Access Journals (Sweden)

    Scott E Nielsen

    Full Text Available Habitat selection is an important behavioural process widely studied for its population-level effects. Models of habitat selection are, however, often fit without a mechanistic consideration. Here, we investigated whether patterns in habitat selection result from instinct or learning for a population of grizzly bears (Ursus arctos in Alberta, Canada. We found that habitat selection and relatedness were positively correlated in female bears during the fall season, with a trend in the spring, but not during any season for males. This suggests that habitat selection is a learned behaviour because males do not participate in parental care: a genetically predetermined behaviour (instinct would have resulted in habitat selection and relatedness correlations for both sexes. Geographic distance and home range overlap among animals did not alter correlations indicating that dispersal and spatial autocorrelation had little effect on the observed trends. These results suggest that habitat selection in grizzly bears are partly learned from their mothers, which could have implications for the translocation of wildlife to novel environments.

  7. Determining habitat quality for species that demonstrate dynamic habitat selection.

    Science.gov (United States)

    Beerens, James M; Frederick, Peter C; Noonburg, Erik G; Gawlik, Dale E

    2015-12-01

    Determining habitat quality for wildlife populations requires relating a species' habitat to its survival and reproduction. Within a season, species occurrence and density can be disconnected from measures of habitat quality when resources are highly seasonal, unpredictable over time, and patchy. Here we establish an explicit link among dynamic selection of changing resources, spatio-temporal species distributions, and fitness for predictive abundance and occurrence models that are used for short-term water management and long-term restoration planning. We used the wading bird distribution and evaluation models (WADEM) that estimate (1) daily changes in selection across resource gradients, (2) landscape abundance of flocks and individuals, (3) conspecific foraging aggregation, and (4) resource unit occurrence (at fixed 400 m cells) to quantify habitat quality and its consequences on reproduction for wetland indicator species. We linked maximum annual numbers of nests detected across the study area and nesting success of Great Egrets (Ardea alba), White Ibises (Eudocimus albus), and Wood Storks (Mycteria americana) over a 20-year period to estimated daily dynamics of food resources produced by WADEM over a 7490 km(2) area. For all species, increases in predicted species abundance in March and high abundance in April were strongly linked to breeding responses. Great Egret nesting effort and success were higher when birds also showed greater conspecific foraging aggregation. Synthesis and applications: This study provides the first empirical evidence that dynamic habitat selection processes and distributions of wading birds over environmental gradients are linked with reproductive measures over periods of decades. Further, predictor variables at a variety of temporal (daily-multiannual) resolutions and spatial (400 m to regional) scales effectively explained variation in ecological processes that change habitat quality. The process used here allows managers to

  8. Greater sage-grouse winter habitat selection and energy development

    Energy Technology Data Exchange (ETDEWEB)

    Doherty, K.E.; Naugle, D.E.; Walker, B.L.; Graham, J.M. [University of Montana, Missoula, MT (United States)

    2008-01-15

    Recent energy development has resulted in rapid and large-scale changes to western shrub-steppe ecosystems without a complete understanding of its potential impacts on wildlife populations. We modeled winter habitat use by female greater sage-grouse (Centrocercus urophasianus) in the Powder River Basin (PRB) of Wyoming and Montana, USA, to 1) identify landscape features that influenced sage-grouse habitat selection, 2) assess the scale at which selection occurred, 3) spatially depict winter habitat quality in a Geographic Information System, and 4) assess the effect of coal-bed natural gas (CBNG) development on winter habitat selection. We developed a model of winter habitat selection based on 435 aerial relocations of 200 radiomarked female sage-grouse obtained during the winters of 2005 and 2006. Percent sagebrush (Artemisia spp.) cover on the landscape was an important predictor of use by sage-grouse in winter. Sage-grouse were 1.3 times more likely to occupy sagebrush habitats that lacked CBNG wells within a 4-km{sup 2} area, compared to those that had the maximum density of 12.3 wells per 4 km{sup 2} allowed on federal lands. We validated the model with 74 locations from 74 radiomarked individuals obtained during the winters of 2004 and 2007. This winter habitat model based on vegetation, topography, and CBNG avoidance was highly predictive (validation R{sup 2} = 0.984). Our spatially explicit model can be used to identify areas that provide the best remaining habitat for wintering sage-grouse in the PRB to mitigate impacts of energy development.

  9. Caribbean mangroves and seagrass beds as diurnal feeding habitats for juvenile French grunts, Haemulon flavolineatum.

    NARCIS (Netherlands)

    Verwey, M.C.; Nagelkerken, I.; Wartenbergh, S.L.J.; Pen, I.R.; Velde, G. van der

    2006-01-01

    Abstract Caribbean seagrass beds are important feeding habitats for so-called nocturnally active zoobenthivorous fish, but the extent to which these fishes use mangroves and seagrass beds as feeding habitats during daytime remains unclear. We hypothesised three feeding strategies: (1) fishes feed o

  10. Caribbean mangroves and seagrass beds as daytime feeding habitats for juvenile French grunts, Haemulon flavolineatum

    NARCIS (Netherlands)

    Verweij, M.C.; Nagelkerken, I.; Wartenbergh, S.L.J.; Pen, I.R.; Van der Velde, G.

    2006-01-01

    Caribbean seagrass beds are important feeding habitats for so-called nocturnally active zoobenthivorous fish, but the extent to which these fishes use mangroves and seagrass beds as feeding habitats during daytime remains unclear. We hypothesised three feeding strategies: (1) fishes feed opportunist

  11. Mangroves and seagrass beds as diurnal feeding habitats for juvenile Haemulon flavolineatum

    NARCIS (Netherlands)

    Verweij, M.C.; Nagelkerken, I.; Wartenbergh, S.L.J.; Pen, I.R.; Velde, G. van der

    2007-01-01

    Caribbean seagrass beds supposedly are important feeding habitats for so-called nocturnally active zoobenthivorous fish, but the extent to which these fishes use mangroves and seagrass beds as feeding habitats during daytime remains unclear. Therefore, we studied daytime behavior of large juvenile (

  12. Habitat selection by juvenile Mojave Desert tortoises

    Science.gov (United States)

    Todd, Brian D; Halstead, Brian J.; Chiquoine, Lindsay P.; Peaden, J. Mark; Buhlmann, Kurt A.; Tuberville, Tracey D.; Nafus, Melia G.

    2016-01-01

    Growing pressure to develop public lands for renewable energy production places several protected species at increased risk of habitat loss. One example is the Mojave desert tortoise (Gopherus agassizii), a species often at the center of conflicts over public land development. For this species and others on public lands, a better understanding of their habitat needs can help minimize negative impacts and facilitate protection or restoration of habitat. We used radio-telemetry to track 46 neonate and juvenile tortoises in the Eastern Mojave Desert, California, USA, to quantify habitat at tortoise locations and paired random points to assess habitat selection. Tortoise locations near burrows were more likely to be under canopy cover and had greater coverage of perennial plants (especially creosote [Larrea tridentata]), more coverage by washes, a greater number of small-mammal burrows, and fewer white bursage (Ambrosia dumosa) than random points. Active tortoise locations away from burrows were closer to washes and perennial plants than were random points. Our results can help planners locate juvenile tortoises and avoid impacts to habitat critical for this life stage. Additionally, our results provide targets for habitat protection and restoration and suggest that diverse and abundant small-mammal populations and the availability of creosote bush are vital for juvenile desert tortoises in the Eastern Mojave Desert.

  13. Post-parturition habitat selection by elk calves and adult female elk in New Mexico

    Science.gov (United States)

    Pitman, J.; Cain, James W.; Liley, Stewart; Gould, William R.; Quintana, Nichole T.; Ballard, Warren

    2014-01-01

    Neonatal survival and juvenile recruitment are crucial to maintaining viable elk (Cervus elaphus) populations. Neonate survival is known to be influenced by many factors, including bed-site selection. Although neonates select the actual bed-site location, they must do so within the larger calf-rearing area selected by the mother. As calves age, habitat selection should change to meet the changing needs of the growing calf. Our main objectives were to characterize habitat selection at 2 spatial scales and in areas with different predator assemblages in New Mexico. We evaluated bed-site selection by calves and calf-rearing area selection by adult females. We captured 108 elk calves by hand and fitted them with ear tag transmitters in two areas in New Mexico: the Valle Vidal and Blue Range Wolf Recovery Area. In both study areas, we found that concealing cover structure and distance to that cover influenced bed-site selection of young calves (i.e., models, but selection was also influenced by forage availability and indices of forage quality. Studies that seek to obtain insight into microhabitat selection of ungulate neonates should consider selection by the neonate and selection by the adult female, changes in selection as neonates age, and potential selection differences in areas of differing predation risk. By considering these influences together and at multiple scales, studies can achieve a broader understanding of neonatal ungulate habitat requirements. 

  14. Grizzly bear habitat selection is scale dependent.

    Science.gov (United States)

    Ciarniello, Lana M; Boyce, Mark S; Seip, Dale R; Heard, Douglas C

    2007-07-01

    The purpose of our study is to show how ecologists' interpretation of habitat selection by grizzly bears (Ursus arctos) is altered by the scale of observation and also how management questions would be best addressed using predetermined scales of analysis. Using resource selection functions (RSF) we examined how variation in the spatial extent of availability affected our interpretation of habitat selection by grizzly bears inhabiting mountain and plateau landscapes. We estimated separate models for females and males using three spatial extents: within the study area, within the home range, and within predetermined movement buffers. We employed two methods for evaluating the effects of scale on our RSF designs. First, we chose a priori six candidate models, estimated at each scale, and ranked them using Akaike Information Criteria. Using this method, results changed among scales for males but not for females. For female bears, models that included the full suite of covariates predicted habitat use best at each scale. For male bears that resided in the mountains, models based on forest successional stages ranked highest at the study-wide and home range extents, whereas models containing covariates based on terrain features ranked highest at the buffer extent. For male bears on the plateau, each scale estimated a different highest-ranked model. Second, we examined differences among model coefficients across the three scales for one candidate model. We found that both the magnitude and direction of coefficients were dependent upon the scale examined; results varied between landscapes, scales, and sexes. Greenness, reflecting lush green vegetation, was a strong predictor of the presence of female bears in both landscapes and males that resided in the mountains. Male bears on the plateau were the only animals to select areas that exposed them to a high risk of mortality by humans. Our results show that grizzly bear habitat selection is scale dependent. Further, the

  15. Establishment of blue mussel beds to enhance fish habitats

    DEFF Research Database (Denmark)

    Kristensen, Louise Dahl; Stenberg, Claus; Støttrup, Josianne;

    2015-01-01

    Human activity has impacted many coastal fjords causing degeneration of the structure and function of the fish habitats. In Nørrefjord, Denmark, local fishermen complained of declining fish catches which could be attributed to eutrophication and extraction of sediments over several decades. This ...... directly on hemp sacs hanging on long-lines was the most effective method. This new method is potentially a useful management tool to improve fish habitats...

  16. Weather conditions drive dynamic habitat selection in a generalist predator

    DEFF Research Database (Denmark)

    Sunde, Peter; Thorup, Kasper; Jacobsen, Lars B.;

    2014-01-01

    Despite the dynamic nature of habitat selection, temporal variation as arising from factors such as weather are rarely quantified in species-habitat relationships. We analysed habitat use and selection (use/availability) of foraging, radio-tagged little owls (Athene noctua), a nocturnal, year-rou...

  17. Sea otters homogenize mussel beds and reduce habitat provisioning in a rocky intertidal ecosystem.

    Directory of Open Access Journals (Sweden)

    Gerald G Singh

    Full Text Available Sea otters (Enhydra lutris are keystone predators that consume a variety of benthic invertebrates, including the intertidal mussel, Mytilus californianus. By virtue of their competitive dominance, large size, and longevity, M. californianus are ecosystem engineers that form structurally complex beds that provide habitat for diverse invertebrate communities. We investigated whether otters affect mussel bed characteristics (i.e. mussel length distributions, mussel bed depth, and biomass and associated community structure (i.e. biomass, alpha and beta diversity by comparing four regions that varied in their histories of sea otter occupancy on the west coast of British Columbia and northern Washington. Mussel bed depth and average mussel lengths were 1.5 times lower in regions occupied by otters for >20 years than those occupied for <5 yrs. Diversity of mussel bed associated communities did not differ between regions; however, the total biomass of species associated with mussel beds was more than three-times higher where sea otters were absent. We examined alternative explanations for differences in mussel bed community structure, including among-region variation in oceanographic conditions and abundance of the predatory sea star Pisaster ochraceus. We cannot discount multiple drivers shaping mussel beds, but our findings indicate the sea otters are an important one. We conclude that, similar to their effects on subtidal benthic invertebrates, sea otters reduce the size distributions of intertidal mussels and, thereby, habitat available to support associated communities. Our study indicates that by reducing populations of habitat-providing intertidal mussels, sea otters may have substantial indirect effects on associated communities.

  18. Giant Panda habitat selection in the Foping Nature Reserve, China

    NARCIS (Netherlands)

    Liu, X.; Toxopeus, A.G.; Skidmore, A.K.; Shao, X.; Dang, D.; Wang, T.; Prins, H.H.T.

    2005-01-01

    Little is known about habitat selection of the giant panda (Ailuropoda melanoleuca), especially about the relationship between giant panda presence and bamboo and tree structures. We presented data on giant panda habitat use and selection in Foping Nature Reserve (NR), China. We used 1,066 radiotrac

  19. Teaching Animal Habitat Selection Using Wildlife Tracking Equipment

    Science.gov (United States)

    Laskowski, Jessica; Gillespie, Caitlyn; Corral, Lucia; Oden, Amy; Fricke, Kent; Fontaine, Joseph J.

    2016-01-01

    We present a hands-on outdoor activity coupled with classroom discussion to teach students about wildlife habitat selection, the process by which animals choose where to live. By selecting locations or habitats with many benefits (e.g., food, shelter, mates) and few costs (e.g., predators), animals improve their ability to survive and reproduce.…

  20. Habitat selection and risk of predation: re-colonization by lynx had limited impact on habitat selection by roe deer.

    Directory of Open Access Journals (Sweden)

    Gustaf Samelius

    Full Text Available Risk of predation is an evolutionary force that affects behaviors of virtually all animals. In this study, we examined how habitat selection by roe deer was affected by risk of predation by Eurasian lynx - the main predator of roe deer in Scandinavia. Specifically, we compared how habitat selection by roe deer varied (1 before and after lynx re-established in the study area and (2 in relation to habitat-specific risk of predation by lynx. All analyses were conducted at the spatial and temporal scales of home ranges and seasons. We did not find any evidence that roe deer avoided habitats in which the risk of predation by lynx was greatest and information-theoretic model selection showed that re-colonization by lynx had limited impact on habitat selection by roe deer despite lynx predation causing 65% of known mortalities after lynx re-colonized the area. Instead we found that habitat selection decreased when habitat availability increased for 2 of 5 habitat types (a pattern referred to as functional response in habitat selection. Limited impact of re-colonization by lynx on habitat selection by roe deer in this study differs from elk in North America altering both daily and seasonal patterns in habitat selection at the spatial scales of habitat patches and home ranges when wolves were reintroduced to Yellowstone National Park. Our study thus provides further evidence of the complexity by which animals respond to risk of predation and suggest that it may vary between ecosystems and predator-prey constellations.

  1. Intercohort density dependence drives brown trout habitat selection

    Science.gov (United States)

    Ayllón, Daniel; Nicola, Graciela G.; Parra, Irene; Elvira, Benigno; Almodóvar, Ana

    2013-01-01

    Habitat selection can be viewed as an emergent property of the quality and availability of habitat but also of the number of individuals and the way they compete for its use. Consequently, habitat selection can change across years due to fluctuating resources or to changes in population numbers. However, habitat selection predictive models often do not account for ecological dynamics, especially density dependent processes. In stage-structured population, the strength of density dependent interactions between individuals of different age classes can exert a profound influence on population trajectories and evolutionary processes. In this study, we aimed to assess the effects of fluctuating densities of both older and younger competing life stages on the habitat selection patterns (described as univariate and multivariate resource selection functions) of young-of-the-year, juvenile and adult brown trout Salmo trutta. We observed all age classes were selective in habitat choice but changed their selection patterns across years consistently with variations in the densities of older but not of younger age classes. Trout of an age increased selectivity for positions highly selected by older individuals when their density decreased, but this pattern did not hold when the density of younger age classes varied. It suggests that younger individuals are dominated by older ones but can expand their range of selected habitats when density of competitors decreases, while older trout do not seem to consider the density of younger individuals when distributing themselves even though they can negatively affect their final performance. Since these results may entail critical implications for conservation and management practices based on habitat selection models, further research should involve a wider range of river typologies and/or longer time frames to fully understand the patterns of and the mechanisms underlying the operation of density dependence on brown trout habitat

  2. Influence of bed heterogeneity and habitat type on macroinvertebrate uptake in peri-urban streams

    Institute of Scientific and Technical Information of China (English)

    REID,H.E.; BRIERLEY,G.J.; BOOTHROYD,I.K.G.

    2010-01-01

    The role of geomorphic structure, referred to as physical heterogeneity, and its influence upon the colonization of habitat by macroinvertebrates was analysed in the peri-urban, Twin Streams Catchment, in West Auckland, New Zealand. Using a cross-scalar approach, 4 riffle-run assemblages were analysed in each of 2 River Styles (a confined, low sinuosity, gravel bed river and a partly confined, low sinuosity, bedrock, cobble, and gravel bed river). Each of these 8 locations comprised 2 distinct sampling areas; the upstream zone had a more heterogeneous river bed with a high diversity of physical features and flow, whilst the downstream area had a more homogeneous structure. Microhabitat features sampled at each site included streambed material, bank margins, fine grained organic debris, wood, and boulders. Habitat mosaics and their associated macroinvertebrate relationships followed a semi-predictable but interrupted pattern, supporting the view that river systems are a patchy discontinuum. Homogeneous zones were more frequently characterised by higher proportions of Trichoptera than heterogeneous zones, whilst heterogeneous zones were frequently characterised by Plecoptera and Ephemeroptera. Diversity was maximised when the species pools from heterogeneous and homogeneous sites were combined for any given site. Functional habitats influenced macroinvertebrate assemblages in non-linear and complex ways. Wood and organic debris habitats were associated with high diversity, abundance, and sensitive species whereas streambed habitat was usually associated with low diversity. A diverse range of physical zones that approximates the 'natural range of behaviour' for the given type of stream was considered to provide a more effective platform for rehabilitation planning than emphasising heterogeneity of physical structure in its own right.

  3. Habitat selection by postbreeding female diving ducks: Influence of habitat attributes and conspecifics

    Science.gov (United States)

    Austin, Jane E.; O'Neil, Shawn T.; Warren, Jeffrey M.

    2016-01-01

    Habitat selection studies of postbreeding waterfowl have rarely focused on within-wetland attributes such as water depth, escape cover, and food availability. Flightless waterfowl must balance habitat selection between avoiding predation risks and feeding. Reproductively successful female ducks face the greatest challenges because they begin the definitive prebasic molt at or near the end of brood rearing, when their body condition is at a low point. We assessed the relative importance of habitat attributes and group effects in habitat selection by postbreeding female lesser scaup Aythya affinis on a 2332-ha montane wetland complex during the peak flightless period (August) over seven years. Hypothesis-based habitat attributes included percent open water, open water:emergent edge density, water depth, percent flooded bare substrate, fetch (distance wind can travel unobstructed), group size, and several interactions representing functional responses to interannual variation in water levels. Surveys of uniquely marked females were conducted within randomly ordered survey blocks. We fitted two-part generalized linear mixed-effects models to counts of marked females within survey blocks, which allowed us to relate habitat attributes to relative probability of occurrence and, given the presence of a marked female, abundance of marked individuals. Postbreeding female scaup selected areas with water depths > 40 cm, large open areas, and intermediate edge densities but showed no relation to flooded bare substrate, suggesting their habitat preferences were more influenced by avoiding predation risks and disturbances than in meeting foraging needs. Grouping behavior by postbreeding scaup suggests habitat selection is influenced in part by behavioral components and/or social information, conferring energetic and survival benefits (predation and disturbance risks) but potentially also contributing to competition for food resources. This study demonstrates the importance of

  4. Masticophis flagellum selects florida scrub habitat at multiple spatial scales

    Science.gov (United States)

    Halstead, B.J.; Mushinsky, H.R.; McCoy, E.D.

    2009-01-01

    The use of space by individual animals strongly influences the spatial extent, abundance, and growth rates of their populations. We analyzed the spatial ecology and habitat selection of Masticophis flagellum (the coachwhip) at three different scales to determine which habitats are most important to this species. Home ranges and mean daily displacements of M. flagellum in Florida were large compared to individuals in other populations of this species. Home ranges contained a greater proportion of Florida scrub habitat than did the study site as a whole, and individuals selected Florida scrub habitat within their home ranges. For both selection of the home range within the study site and selection of habitats within the home range, mesic cutthroat and hydric swamp habitats were avoided. Standardized selection ratios of Florida scrub patches were positively correlated with lizard abundance. Several non-mutually exclusive mechanisms, including foraging success (prey abundance, prey vulnerability, and foraging efficiency), abundance of refugia, and thermoregulatory opportunity may underlie the selection of Florida scrub by M. flagellum. Historic rarity and anthropogenic loss and fragmentation of Florida scrub habitat, coupled with the long-distance movements, large home ranges, and selection of Florida scrub by M. flagellum, indicate that large contiguous tracts of land containing Florida scrub will be essential for the persistence of M. flagellum in central Florida. ?? 2009 by The Herpetologists' League, Inc.

  5. Sage-grouse habitat selection during winter in Alberta

    Science.gov (United States)

    Carpenter, J.; Aldridge, C.; Boyce, M.S.

    2010-01-01

    Greater sage-grouse (Centrocercus urophasianus) are dependent on sagebrush (Artemisia spp.) for food and shelter during winter, yet few studies have assessed winter habitat selection, particularly at scales applicable to conservation planning. Small changes to availability of winter habitats have caused drastic reductions in some sage-grouse populations. We modeled winter habitat selection by sage-grouse in Alberta, Canada, by using a resource selection function. Our purpose was to 1) generate a robust winter habitat-selection model for Alberta sage-grouse; 2) spatially depict habitat suitability in a Geographic Information System to identify areas with a high probability of selection and thus, conservation importance; and 3) assess the relative influence of human development, including oil and gas wells, in landscape models of winter habitat selection. Terrain and vegetation characteristics, sagebrush cover, anthropogenic landscape features, and energy development were important in top Akaike's Information Criterionselected models. During winter, sage-grouse selected dense sagebrush cover and homogenous less rugged areas, and avoided energy development and 2-track truck trails. Sage-grouse avoidance of energy development highlights the need for comprehensive management strategies that maintain suitable habitats across all seasons. ?? 2010 The Wildlife Society.

  6. Modelling the negative effects of landscape fragmentation on habitat selection

    NARCIS (Netherlands)

    Langevelde, van F.

    2015-01-01

    Landscape fragmentation constrains movement of animals between habitat patches. Fragmentation may, therefore, limit the possibilities to explore and select the best habitat patches, and some animals may have to cope with low-quality patches due to these movement constraints. If so, these individuals

  7. Determinants of habitat selection by hatchling Australian freshwater crocodiles.

    Directory of Open Access Journals (Sweden)

    Ruchira Somaweera

    Full Text Available Animals almost always use habitats non-randomly, but the costs and benefits of using specific habitat types remain unknown for many types of organisms. In a large lake in northwestern Australia (Lake Argyle, most hatchling (<12-month-old freshwater crocodiles (Crocodylus johnstoni are found in floating vegetation mats or grassy banks rather than the more widely available open banks. Mean body sizes of young crocodiles did not differ among the three habitat types. We tested four potential explanations for non-random habitat selection: proximity to nesting sites, thermal conditions, food availability, and exposure to predation. The three alternative habitat types did not differ in proximity to nesting sites, or in thermal conditions. Habitats with higher food availability harboured more hatchlings, and feeding rates (obtained by stomach-flushing of recently-captured crocodiles were highest in such areas. Predation risk may also differ among habitats: we were twice as likely to capture a crocodile after seeing it in open-bank sites than in the other two habitat types. Thus, habitat selection of hatchling crocodiles in this system may be driven both by prey availability and by predation risk.

  8. Rhodolith beds in Brazil: a new potential habitat for marine bioprospection

    Directory of Open Access Journals (Sweden)

    Gilberto M. Amado-Filho

    2012-08-01

    Full Text Available Rhodoliths are the free-living forms of a number of nongeniculate coralline algae. Rhodolith beds are a common feature of subtidal environments and have been recognized as important carbonate producers and paleoenvironmental indicators, as well as recognized as habitat-forming species. The rhodolith structure provides a hard three-dimensional substrate serving as microhabitat for a wide range of biodiversity, including commercially importance species. The largest known latitudinal occurrence range of rhodolith beds ais on the Brazilian coastal shelf from 2°N to 25°S. Despite their importance for the Brazilian benthic communities, only in the last decade sampling efforts allowed a more comprehensive understanding of the beds' distribution, their structure and associated communities, as well as data concerning the influence of environmental factors on rhodolith bed structure and dynamics. In this work, we review the available information on the biodiversity associated with the recently described Brazilian rhodolith beds of the continental shelf and oceanic islands, focusing on the associated organisms with potential for bioprospection research.

  9. Quantifying spatial habitat loss from hydrocarbon development through assessing habitat selection patterns of mule deer.

    Science.gov (United States)

    Northrup, Joseph M; Anderson, Charles R; Wittemyer, George

    2015-11-01

    Extraction of oil and natural gas (hydrocarbons) from shale is increasing rapidly in North America, with documented impacts to native species and ecosystems. With shale oil and gas resources on nearly every continent, this development is set to become a major driver of global land-use change. It is increasingly critical to quantify spatial habitat loss driven by this development to implement effective mitigation strategies and develop habitat offsets. Habitat selection is a fundamental ecological process, influencing both individual fitness and population-level distribution on the landscape. Examinations of habitat selection provide a natural means for understanding spatial impacts. We examined the impact of natural gas development on habitat selection patterns of mule deer on their winter range in Colorado. We fit resource selection functions in a Bayesian hierarchical framework, with habitat availability defined using a movement-based modeling approach. Energy development drove considerable alterations to deer habitat selection patterns, with the most substantial impacts manifested as avoidance of well pads with active drilling to a distance of at least 800 m. Deer displayed more nuanced responses to other infrastructure, avoiding pads with active production and roads to a greater degree during the day than night. In aggregate, these responses equate to alteration of behavior by human development in over 50% of the critical winter range in our study area during the day and over 25% at night. Compared to other regions, the topographic and vegetative diversity in the study area appear to provide refugia that allow deer to behaviorally mediate some of the impacts of development. This study, and the methods we employed, provides a template for quantifying spatial take by industrial activities in natural areas and the results offer guidance for policy makers, mangers, and industry when attempting to mitigate habitat loss due to energy development.

  10. Quantifying spatial habitat loss from hydrocarbon development through assessing habitat selection patterns of mule deer.

    Science.gov (United States)

    Northrup, Joseph M; Anderson, Charles R; Wittemyer, George

    2015-11-01

    Extraction of oil and natural gas (hydrocarbons) from shale is increasing rapidly in North America, with documented impacts to native species and ecosystems. With shale oil and gas resources on nearly every continent, this development is set to become a major driver of global land-use change. It is increasingly critical to quantify spatial habitat loss driven by this development to implement effective mitigation strategies and develop habitat offsets. Habitat selection is a fundamental ecological process, influencing both individual fitness and population-level distribution on the landscape. Examinations of habitat selection provide a natural means for understanding spatial impacts. We examined the impact of natural gas development on habitat selection patterns of mule deer on their winter range in Colorado. We fit resource selection functions in a Bayesian hierarchical framework, with habitat availability defined using a movement-based modeling approach. Energy development drove considerable alterations to deer habitat selection patterns, with the most substantial impacts manifested as avoidance of well pads with active drilling to a distance of at least 800 m. Deer displayed more nuanced responses to other infrastructure, avoiding pads with active production and roads to a greater degree during the day than night. In aggregate, these responses equate to alteration of behavior by human development in over 50% of the critical winter range in our study area during the day and over 25% at night. Compared to other regions, the topographic and vegetative diversity in the study area appear to provide refugia that allow deer to behaviorally mediate some of the impacts of development. This study, and the methods we employed, provides a template for quantifying spatial take by industrial activities in natural areas and the results offer guidance for policy makers, mangers, and industry when attempting to mitigate habitat loss due to energy development. PMID:26264447

  11. Adaptive breeding habitat selection: Is it for the birds?

    Science.gov (United States)

    Chalfoun, Anna D.; Schmidt, Kenneth A.

    2012-01-01

    The question of why animals choose particular habitats has important implications for understanding behavioral evolution and distribution of organisms in the wild and for delineating between habitats of different quality for conservation and management. Habitats chosen by animals can influence fitness outcomes via the costs (e.g., predation risk) and benefits (e.g., food availability) of habitat use. Habitat preferences should therefore be under selection to favor those that confer fitness advantages (Clark and Shutler 1999). Indeed, prevailing theory suggests that the habitat preferences of animals should be adaptive, such that fitness is higher in preferred habitats (Hildén 1965, Southwood 1977, Martin 1998). However, studies have often identified apparent mismatches between observed habitat preferences and fitness outcomes across a wide variety of taxa (Valladares and Lawton 1991, Mayhew 1997, Kolbe and Janzen 2002, Arlt and Pärt 2007, Mägi et al. 2009). Certainly, one limitation of studies may be that assessment of “fitness” is typically constrained to fitness surrogates such as nest success rather than lifetime reproductive success or classic Fisherian fitness (Endler 1986). Nevertheless, important habitat choices such as nest sites influence the probability that temporarily sedentary, dependent young are discovered by enemies such as predators and parasites. We therefore expect, on average, to see congruence between evolved habitat preferences and relevant components of fitness (e.g., nest success). Here, we (1) review the prevalence of apparent mismatches between avian breeding-habitat preferences and fitness outcomes using nest-site selection as a focus; (2) describe several potential mechanisms for such mismatches, including anthropogenic, methodological, and ecological–evolutionary; and (3) suggest a framework for understanding the contexts in which habitat preferences represent adaptive decisions, with a primary focus on ecological information

  12. Habitat selection and indirect interactions in fish communities

    OpenAIRE

    Beier, Ulrika

    2013-01-01

    To increase the understanding of freshwater lake ecosystems, I have studied the habitat selection of perch (Perca fluviatilis L.), roach (Rutilus rutilus (L.)), and vendace (Coregonus albula (L.)). These fish species use the pelagic and the littoral-benthic habitats in lakes to different extents. Perch and roach are omnivorous, and perch become piscivorous at larger sizes. Vendace is a pelagic species specialized in eating zooplankton. Vendace was expected to affect biotic interactions and ha...

  13. Habitat selection and consumption across a landscape of multiple predators

    OpenAIRE

    Wesner, Jeff S; Meyers, Peter; Eric J. Billman; Mark C Belk

    2014-01-01

    Predator community composition can alter habitat quality for prey by changing the strength and direction of consumptive effects. Whether predator community composition also alters prey density via nonconsumptive effects during habitat selection is not well known, but is important for understanding how changes to predator communities will alter prey populations. We tested the hypothesis that predator community composition (presence of caged trout, caged dragonflies, or caged trout + dragonflie...

  14. Weather conditions drive dynamic habitat selection in a generalist predator.

    Directory of Open Access Journals (Sweden)

    Peter Sunde

    Full Text Available Despite the dynamic nature of habitat selection, temporal variation as arising from factors such as weather are rarely quantified in species-habitat relationships. We analysed habitat use and selection (use/availability of foraging, radio-tagged little owls (Athene noctua, a nocturnal, year-round resident generalist predator, to see how this varied as a function of weather, season and availability. Use of the two most frequently used land cover types, gardens/buildings and cultivated fields varied more than 3-fold as a simple function of season and weather through linear effects of wind and quadratic effects of temperature. Even when controlling for the temporal context, both land cover types were used more evenly than predicted from variation in availability (functional response in habitat selection. Use of two other land cover categories (pastures and moist areas increased linearly with temperature and was proportional to their availability. The study shows that habitat selection by generalist foragers may be highly dependent on temporal variables such as weather, probably because such foragers switch between weather dependent feeding opportunities offered by different land cover types. An opportunistic foraging strategy in a landscape with erratically appearing feeding opportunities in different land cover types, may possibly also explain decreasing selection of the two most frequently used land cover types with increasing availability.

  15. Movement is the glue connecting home ranges and habitat selection.

    Science.gov (United States)

    Van Moorter, Bram; Rolandsen, Christer M; Basille, Mathieu; Gaillard, Jean-Michel

    2016-01-01

    Animal space use has been studied by focusing either on geographic (e.g. home ranges, species' distribution) or on environmental (e.g. habitat use and selection) space. However, all patterns of space use emerge from individual movements, which are the primary means by which animals change their environment. Individuals increase their use of a given area by adjusting two key movement components: the duration of their visit and/or the frequency of revisits. Thus, in spatially heterogeneous environments, animals exploit known, high-quality resource areas by increasing their residence time (RT) in and/or decreasing their time to return (TtoR) to these areas. We expected that spatial variation in these two movement properties should lead to observed patterns of space use in both geographic and environmental spaces. We derived a set of nine predictions linking spatial distribution of movement properties to emerging space-use patterns. We predicted that, at a given scale, high variation in RT and TtoR among habitats leads to strong habitat selection and that long RT and short TtoR result in a small home range size. We tested these predictions using moose (Alces alces) GPS tracking data. We first modelled the relationship between landscape characteristics and movement properties. Then, we investigated how the spatial distribution of predicted movement properties (i.e. spatial autocorrelation, mean, and variance of RT and TtoR) influences home range size and hierarchical habitat selection. In landscapes with high spatial autocorrelation of RT and TtoR, a high variation in both RT and TtoR occurred in home ranges. As expected, home range location was highly selective in such landscapes (i.e. second-order habitat selection); RT was higher and TtoR lower within the selected home range than outside, and moose home ranges were small. Within home ranges, a higher variation in both RT and TtoR was associated with higher selectivity among habitat types (i.e. third-order habitat

  16. The spatial scaling of habitat selection by African elephants.

    Science.gov (United States)

    de Knegt, Henrik J; van Langevelde, Frank; Skidmore, Andrew K; Delsink, Audrey; Slotow, Rob; Henley, Steve; Bucini, Gabriela; de Boer, Willem F; Coughenour, Michael B; Grant, Cornelia C; Heitkönig, Ignas M A; Henley, Michelle; Knox, Nicky M; Kohi, Edward M; Mwakiwa, Emmanuel; Page, Bruce R; Peel, Mike; Pretorius, Yolanda; van Wieren, Sipke E; Prins, Herbert H T

    2011-01-01

    1. Understanding and accurately predicting the spatial patterns of habitat use by organisms is important for ecological research, biodiversity conservation and ecosystem management. However, this understanding is complicated by the effects of spatial scale, because the scale of analysis affects the quantification of species-environment relationships. 2. We therefore assessed the influence of environmental context (i.e. the characteristics of the landscape surrounding a site), varied over a large range of scales (i.e. ambit radii around focal sites), on the analysis and prediction of habitat selection by African elephants in Kruger National Park, South Africa. 3. We focused on the spatial scaling of the elephants' response to their main resources, forage and water, and found that the quantification of habitat selection strongly depended on the scales at which environmental context was considered. Moreover, the inclusion of environmental context at characteristic scales (i.e. those at which habitat selectivity was maximized) increased the predictive capacity of habitat suitability models. 4. The elephants responded to their environment in a scale-dependent and perhaps hierarchical manner, with forage characteristics driving habitat selection at coarse spatial scales, and surface water at fine spatial scales. 5. Furthermore, the elephants exhibited sexual habitat segregation, mainly in relation to vegetation characteristics. Male elephants preferred areas with high tree cover and low herbaceous biomass, whereas this pattern was reversed for female elephants. 6. We show that the spatial distribution of elephants can be better understood and predicted when scale-dependent species-environment relationships are explicitly considered. This demonstrates the importance of considering the influence of spatial scale on the analysis of spatial patterning in ecological phenomena.

  17. Winter habitat selection of red-crowned crane (Grus japonensis)

    Institute of Scientific and Technical Information of China (English)

    张洪海; 杨月伟

    2000-01-01

    This paper studied the winter habitat selection of red-crowned cranes (Grus japonensis) in Yancheng National Natural Reserve, Jiangsu Province. There were six types of habitat used by red-crowned cranes, i.e. salt-works, aquiculture ponds, reed lands, grassy tidal lands, salting wormwood lands and wheat fields. The wheat field was a new type of habitat used by red-crowned cranes. More than 70 percent of red-crowned cranes chose grassy tidal lands, salting wormwood lands, and reed lands as their most important habitats. In recent years, the distribution of red-crowned cranes moved southward gradually. Red-crowned cranes prefer artificial or semi-artificial wetlands rather than original wetlands, successive distribution was broken into fragments.

  18. Ecological specialisation in habitat selection within a macropodid herbivore guild.

    Science.gov (United States)

    Garnick, Sarah; Di Stefano, Julian; Elgar, Mark A; Coulson, Graeme

    2016-03-01

    Specialist species show stronger resource selection, narrower niches and lower niche overlap than generalist species. We examined ecological specialisation with respect to habitat selection in a macropodid community comprising the western grey kangaroo Macropus fuliginosus, red-necked wallaby M. rufogriseus and swamp wallaby Wallabia bicolor in the Grampians National Park, Victoria, Australia. We used radio tracking to quantify habitat selection. We predicted that because the fitness benefits of generalisation and specialisation differ, there would be a mix of generalised and specialised species in our community. As all three macropodid species show marked sexual dimorphism, we also expected that they would show sex-based specialisation. Finally, because many large herbivores select different habitats for foraging and resting, we predicted that our species would specialise on a subset of their overall selected habitat based on activity period (diurnal or nocturnal). All three species specialised on the available resources to some degree. Western grey kangaroos were specialists, at least during the active period. Niche data for the two wallaby species were harder to interpret so we could not determine their degree of specialisation. Within species, we found no evidence of sex-based specialisation. However, we found clear evidence of specialisation by activity period in western grey kangaroos and red-necked wallabies, but not in swamp wallabies. The strength of behavioural decisions made during the active period in influencing specialisation points to the likelihood that bottom-up processes regulate this community. PMID:26621691

  19. Home Range, Habitat Selection, and Foraging Rhythm in Mauritanian Spoonbills (

    NARCIS (Netherlands)

    El-Hacen, E.-H.M.; Overdijk, O.; Lok, T.; Olff, H.; Piersma, T.

    2013-01-01

    Mauritanian Spoonbills (Platalea leucorodia balsaci) only breed at Banc d'Arguin, Mauritania, West Africa. Their populations have declined; however, nothing is known about possible ecological factors involved, including their primary food and foraging habits. Home range sizes, habitat selection, and

  20. Habitat Selection and Activity Pattern of GPS Collared Sumateran Tigers

    Directory of Open Access Journals (Sweden)

    Dolly Priatna

    2012-12-01

    Full Text Available Although translocation has been used in mitigating human-carnivore conflict for decades, few studies have been conducted on the behavioral ecology of released animals. Such information is necessary in the context of sustainable forest management. In this study we determine the type of land cover used as main habitat and examine the activity pattern of translocated tigers. Between 2008 and 2010 we captured six conflict tigers and translocated them 74-1,350 km from their capture sites in Sumatera. All tigers were fitted with global positioning system (GPS collars. The collars were set to fix 24-48 location coordinates per day.  All translocated tigers showed a preference for a certain habitat type within their new home range, and tended to select the majority of natural land cover type within the landscape as their main habitat, but the availability of natural forest habitat within the landscape remains essensial for their survival. The activity of male translocated tigers differed significantly between the six time intervals of 24 hours, and their most active periods were in the afternoon (14:00-18:00 hours and in the evening (18:00-22:00 hours. Despite being preliminary, the findings of this study-which was the first such study conducted in Sumatera-highlight the conservation value of tiger translocation and provide valuable information for improving future management of conflict tigers.Keywords: activity pattern, GPS collars, habitat selection, sumateran tiger, translocation

  1. Defining the scale of habitat availability for models of habitat selection.

    Science.gov (United States)

    Paton, Robert Stephen; Matthiopoulos, Jason

    2016-05-01

    Statistical models of habitat preference and species distribution (e.g., Resource Selection Functions and Maximum Entropy approaches) perform a quantitative comparison of the use of space with the availability of all habitats in an animal's environment. However, not all of space is accessible all of the time to all individuals, so availability is in fact determined by limitations in animal perception and mobility. Therefore, measuring habitat availability at biologically relevant scales is essential for understanding preference, but herein lies a trade-off: Models fitted at large spatial scales, will tend to average across the responses of different individuals that happen to be in regions with contrasting habitat compositions. We suggest that such models may fail to capture local extremes (hotspots and coldspots) in animal usage and call this potential problem, homogenization. In contrast, models fitted at smaller scales will vary stochastically depending on the particular habitat composition of their narrow spatial neighborhood, and hence fail to describe responses when predicting for different sampling instances. This is the now well-documented issue of non-transferability of habitat models. We illustrate this tradeoff, using a range of simulated experiments, incorporating variations in environmental gradients, richness and fragmentation. We propose diagnostics for detecting the two issues of homogenization and non-transferability and show that these scale-related symptoms are likely to be more pronounced in highly fragmented or steeply graded landscapes. Further, we address these problems by treating the neighborhood of each cell in the landscape grid as an individual sampling instance (with its own neighborhood), hence allowing coefficients to respond to the local expectations of environmental variables according to a Generalized Functional Response (GFR). Under simulation this approach is consistently better at estimating robust (i.e., transferable) habitat

  2. Cold-water coral mounds and sponge-beds as habitats for demersal fish on the Norwegian shelf

    Science.gov (United States)

    Kutti, Tina; Bergstad, Odd Aksel; Fosså, Jan Helge; Helle, Kristin

    2014-01-01

    The importance of cold-water coral (CWC) mounds and sponge-beds as habitat for demersal fish was examined in the Træna Deep marine protected area and adjacent areas of the Norwegian continental shelf. Standardised longline fishing was conducted twice, in June and March, and predetermined fishing effort was allocated to multiple plots with varying densities of small CWC mounds and sponges, plus control plots with neither of these habitats. Catches within all examined habitats were dominated by the commercially exploited Brosme brosme (representing >70% of the total catch) followed by Galeus melastomus, Chimaera monstrosa, Etmopterus spinax and the commercially exploited Molva molva. Positive correlations were found between catch rates of B. brosme, G. melastomus and C. monstrosa and the density of small CWC mounds at one or both sampling occasions. No correlations were found between the catch rates of the same three species and sponge density; thus the sponge-beds did not seem to represent an ecologically equivalent habitat to the CWCs. On a local scale the CWC habitat appeared to attract higher abundances of B. brosme, G. melastomus and C. monstrosa; however, the differences in catch rates between coral and non-coral areas were quite low (2-4 times) and for most species the fish-habitat relationships varied temporarily and with the spatial scale used to delineate the habitat. Based on the methods and the results of this study and the fact that CWCs only occupy a very small proportion of the Norwegian shelf, the importance of CWCs as habitat for the populations of the demersal fish species examined is judged as marginal.

  3. Habitat selection of a declining white-tailed deer herd in the central Black Hills, South Dakota and Wyoming

    Science.gov (United States)

    Deperno, Christopher Shannon

    Habitat selection, survival rates, the Black Hills National Forest Habitat Capability Model (HABCAP), and the USDA Forest Service Geographic Information System (GIS) data base were evaluated for a declining white-tailed deer (Odocoileus virginianus dacotensis) herd in the central Black Hills of South Dakota and Wyoming. From July 1993 through July 1996, 73 adult and yearling female and 12 adult and yearling male white-tailed deer were radiocollared and visually monitored. Habitat information was collected at 4,662 white-tailed deer locations and 1,087 random locations. Natural mortality (71%) was the primary cause of female mortality, followed by harvest (22.5%) and accidental causes (6.5%). More females died in spring (53.2%) than in fall (22.6%), winter (14.5%), or summer (9.7%). Male mortality resulted from hunting in fall (66.7%) and natural causes in spring (33.3%). Survival rates for all deer by year were 62.1% in 1993, 51.1% in 1994, 56.4% in 1995, and 53.9% in 1996 and were similar (P = 0.691) across years. During winter, white-tailed deer selected ponderosa pine- (Pinus ponderosa ) deciduous and burned pine cover types. Overstory-understory habitats selected included pine/grass-forb, pine/bearberry (Arctostaphylos uva-ursi), pine/snowberry (Symphoricarpos albus), burned pine/grass-forb, and pine/shrub habitats. Structural stages selected included sapling-pole pine stands with >70% canopy cover, burned pine sapling-pole and saw-timber stands with 40% canopy cover and all sapling-pole pine structural stages; sapling-pole stands with >70% canopy cover received the greatest use. White-tailed deer primarily fed in pine saw-timber structural stage with less than 40% canopy cover. Overall, selected habitats contained lower amounts of grass/forb, shrubs, and litter than random locations. Male and female deer generally bedded in areas that were characterized by greater horizontal cover than feeding and random sites. When feeding and bedding sites were combined

  4. Selecting appropriate bedding to reduce locomotion problems in broilers

    Directory of Open Access Journals (Sweden)

    ICL Almeida Paz

    2010-09-01

    Full Text Available Two experiments were carried out at the Poultry Sector of the School of Agrarian Sciences of the Federal University of Grande Dourados to evaluate the incidence of leg problems in broilers reared on two distinct types of bedding material: rice husks or wood shavings, both new and reused. In both trials, a randomized experimental design was applied in factorial arrangement (2 x 2 x 2 using two genetic strains (Cobb® or Ross®; two sexes (male or female, and two litter materials (rice husks or wood shavings. In each trial 1080 one day pullets were reared equally divided in the treatments. The birds were placed in 4.5 m² boxes at a density of 10 birds m-2. All birds were fed diets with equal nutritional density, and water was offered ad libitum. Feeds were divided in three phases: starter diet (1 - 21 days, grower diet (22 - 35 days, and finisher diet (36 - 45 days. On day 45, fifty birds were randomly selected in each experiment to evaluate flock leg problems. The following parameters were analyzed: gait score, incidence of valgus and varus disorder, footpad dermatitis, femoral degeneration, tibial dyschondroplasia, and spondylolisthesis. Ambient temperature during rearing and litter caking and moisture content were recorded in four boxes per treatment. The analytical hierarchy process was used to organize the data into specific criteria. Several criteria, related to the attributes that were determinant according to the statistical analysis, were chosen in order to provide the best input to the process. Results indicated that new wood-shavings bedding was the most appropriate bedding to prevent locomotion problems, followed by new rice husks, reused wood shavings, and reused rice husks. However, when leg problems were associated to sex and genetic strain, male Ross birds strain presented less problems when reared on new rice husks, followed by new wood shavings

  5. Behavioural cues surpass habitat factors in explaining prebreeding resource selection by a migratory diving duck

    Science.gov (United States)

    O'Neil, Shawn T.; Warren, Jeffrey M.; Takekawa, John Y.; De La Cruz, Susan E. W.; Cutting, Kyle A.; Parker, Michael W.; Yee, Julie L.

    2014-01-01

    Prebreeding habitat selection in birds can often be explained in part by habitat characteristics. However, females may also select habitats on the basis of fidelity to areas of previous reproductive success or use by conspecifics. The relative influences of sociobehavioural attributes versus habitat characteristics in habitat selection has been primarily investigated in songbirds, while less is known about how these factors affect habitat selection processes in migratory waterfowl. Animal resource selection models often exhibit much unexplained variation; spatial patterns driven by social and behavioural characteristics may account for some of this. We radiomarked female lesser scaup, Aythya affinis, in the southwestern extent of their breeding range to explore hypotheses regarding relative roles of habitat quality, site fidelity and conspecific density in prebreeding habitat selection. We used linear mixed-effects models to relate intensity of use within female home ranges to habitat features, distance to areas of reproductive success during the previous breeding season and conspecific density. Home range habitats included shallow water (≤118 cm), moderate to high densities of flooded emergent vegetation/open water edge and open water areas with submerged aquatic vegetation. Compared with habitat features, conspecific female density and proximity to successful nesting habitats from the previous breeding season had greater influences on habitat use within home ranges. Fidelity and conspecific attraction are behavioural characteristics in some waterfowl species that may exert a greater influence than habitat features in influencing prebreeding space use and habitat selection within home ranges, particularly where quality habitat is abundant. These processes may be of critical importance to a better understanding of habitat selection in breeding birds.

  6. Repellency of selected chemicals against the bed bug (Hemiptera: Cimicidae).

    Science.gov (United States)

    Wang, Changlu; Lü, Lihua; Zhang, Aijun; Liu, Chaofeng

    2013-12-01

    In recent years, the common bed bug, Cimex lectularius L. (Hemiptera: Cimicidae), became a major public health concern in urban communities. Bed bugs are notoriously difficult to control, and their bites are not tolerated by most people. The public has an urgent need for materials and methods to reduce bed bug introduction and bites during work, travel, or sleep. A repellent product will help achieve these goals by discouraging and preventing bed bugs from moving to a protected area. We evaluated the repellency of three commercially available insect repellent or control materials and five nonregistered materials with the goal of identifying safe and effective bed bug repellents. The two commercial repellent products that contained 7% picaridin or 0.5% permethrin had little repellency against bed bugs. N,N-diethyl-m-toluamide (DEET), the most commonly used insect repellent, provided a high level of repellency against bed bugs. When a host cue (carbon dioxide) was present, the minimum DEET concentration to repel > or = 94% of the bed bugs for a9-h period was 10%. The longevity of repellency of DEET was concentration dependent. At 25% concentration, DEET-treated fabric surface remained highly repellent to bed bugs for a 14-d period. However, DEET has a strong smell and dissolves certain plastic materials. Therefore, we evaluated several odorless, noncorrosive, and potentially effective repellents. Isolongifolenone and isolongifolanone, two natural products and recently reported insect repellents, exhibited strong repellent property against bed bugs but at significantly lower levels than DEET. Three novel potential repellent compounds discovered by Bedoukian Research Inc. (Danbury, CT) exhibited similar level of repellency and longevity as DEET for repelling bed bugs. These nonirritant and odorless compounds are promising candidates as alternatives to DEET for reducing the spread of bed bugs and bed bug bites. PMID:24498754

  7. Differential fitness in field and forest explains density-independent habitat selection by gartersnakes.

    Science.gov (United States)

    Halliday, William D; Blouin-Demers, Gabriel

    2016-07-01

    The ideal free distribution concept predicts that organisms will distribute themselves between habitats in a density-dependent manner so that individuals, on average, achieve the same fitness in each habitat. In ectotherms, environmental temperature has a strong impact on fitness, but temperature is not depletable and thus not density dependent. Can density-dependent habitat selection occur in ectotherms when habitats differ in thermal quality? We used an observational study of habitat selection by small snakes in field and forest, followed by manipulative habitat selection and fitness experiments with common gartersnakes in enclosures in field and forest to test this hypothesis. Snakes were much more abundant in the field, the habitat with superior thermal quality, than in the forest. Gartersnakes in our controlled experiment only used the forest habitat when snake density was highest and when food was more abundant in the forest; habitat selection was largely density independent, although there was weak evidence of density dependence. No female gartersnake gave birth in the forest enclosures, whereas half of the females gave birth in the field enclosures. Growth rates of females were higher in field than in forest enclosures. Overall, our data indicate that temperature appears to be the most important factor driving the habitat selection of gartersnakes, likely because temperature was more limiting than food in our study system. Snakes, or at least temperate snakes, may naturally exist at population densities low enough that they do not exhibit density-dependent habitat selection. PMID:27016079

  8. Repellency of selected chemicals against the bed bug, (hemiptra: Cimicidae)

    Science.gov (United States)

    In recent years, the common bed bug, Cimex lectularius L. (Hemiptera: Cimicidae), became a major public health concern in urban communities. Bed bugs are notoriously difficult to control and their painful bites are not tolerated by most people. The public has a strong need for materials and methods ...

  9. Daytime habitat selection for juvenile parr brown trout (Salmo trutta) in small lowland streams

    DEFF Research Database (Denmark)

    Conallin, J.; Boegh, E.; Olsen, M.;

    2014-01-01

    Physical habitat is important in determining the carrying capacity of juvenile brown trout, and within freshwater management. Summer daytime physical habitat selection for the parr lifestage (7-20 cm) juvenile brown trout (Salmo trutta) was assessed in 6 small lowland streams. Habitat preference...

  10. Scale-Dependent Habitat Selection and Size-Based Dominance in Adult Male American Alligators.

    Science.gov (United States)

    Strickland, Bradley A; Vilella, Francisco J; Belant, Jerrold L

    2016-01-01

    Habitat selection is an active behavioral process that may vary across spatial and temporal scales. Animals choose an area of primary utilization (i.e., home range) then make decisions focused on resource needs within patches. Dominance may affect the spatial distribution of conspecifics and concomitant habitat selection. Size-dependent social dominance hierarchies have been documented in captive alligators, but evidence is lacking from wild populations. We studied habitat selection for adult male American alligators (Alligator mississippiensis; n = 17) on the Pearl River in central Mississippi, USA, to test whether habitat selection was scale-dependent and individual resource selectivity was a function of conspecific body size. We used K-select analysis to quantify selection at the home range scale and patches within the home range to determine selection congruency and important habitat variables. In addition, we used linear models to determine if body size was related to selection patterns and strengths. Our results indicated habitat selection of adult male alligators was a scale-dependent process. Alligators demonstrated greater overall selection for habitat variables at the patch level and less at the home range level, suggesting resources may not be limited when selecting a home range for animals in our study area. Further, diurnal habitat selection patterns may depend on thermoregulatory needs. There was no relationship between resource selection or home range size and body size, suggesting size-dependent dominance hierarchies may not have influenced alligator resource selection or space use in our sample. Though apparent habitat suitability and low alligator density did not manifest in an observed dominance hierarchy, we hypothesize that a change in either could increase intraspecific interactions, facilitating a dominance hierarchy. Due to the broad and diverse ecological roles of alligators, understanding the factors that influence their social dominance

  11. Nesting habitat selection by sage grouse in southcentral Washington

    Science.gov (United States)

    Sveum, C.M.; Edge, W.D.; Crawford, J.A.

    1998-01-01

    To characterize western sage grouse (Centrocercus urophasianus phaios Bonaparte) nesting habitat in sagebrush-steppe habitat in Washington, we initiated a study on the Yakima Training Center to determine nesting habitat characteristics and whether these characteristics differed between successful and depredated nests. Most nests (71%) were in big sagebrush (Artemesia tridentata Nutt.)/bunchgrass communities. Nest habitat was characterized by greater shrub cover, shrub height, vertical cover height, residual cover, and litter than at random locations. Successful 1-m2 nest sites within big sagebrush/bunchgrass in 1992 had less shrub cover (51%) and shrub height (64 cm) than depredated nest sites (70% and 90 cm, respectively). Successful 77-m2 nest areas in big sagebrush/bunchgrass in 1993 had more tall grass (??? 18 cm) than depredated nest areas. Management that protects the big sagebrush/bunchgrass community is essential for maintaining nesting habitat for sage grouse.

  12. Fluid Bed Technology: Overview and Parameters for Process Selection

    Directory of Open Access Journals (Sweden)

    Saurabh Srivastava

    2010-10-01

    Full Text Available Formulation development is the most emerging and upcoming face of pharmaceutical technology in the current era. It is contemporarily capturing the market leaps and bounds with recent trends and developments with its innovative techniques. The day-to-day advancements in the research have provided an edge to this brilliant branch of pharmaceutical sector for not only uplifting the pharmacy profession but also to conquer the diseased state for nurturing the health and humanity. The fluid-bed technology or air-suspension process is the potential tool to develop newer trends and implications in the sector of formulation development with maximum therapeutic efficacy. The technology is used for granulation/agglomeration, layering and coating of a wide range of particle size. In addition; the technique can be used for the drying process as well. The three patterns of the fluid-bed processes could be characterized by the position/location of the spray nozzle i.e. top spray, bottom spray or tangential spray. This article reviews the three techniques with some innovative fluid bed pelletizing technologies like CPS™, MicroPx™, ProCell™ and discusses their applications, advantages and limitations. These advanced pelletizing technologies are recentely added to complement the actual capabilities of standard fluid bed processing for development of various dosage forms of “Multiple Unit Particulate Systems” (MUPS with better therapeutic efficacy and economic benefits.

  13. Seagrass beds as ocean acidification refuges for mussels? High resolution measurements of pCO2 and O2 in a Zostera marina and Mytilus edulis mosaic habitat

    OpenAIRE

    V. Saderne; P. Fietzek; S. Aßmann; A. Körtzinger; C. Hiebenthal

    2015-01-01

    It has been speculated that macrophytes beds might act as a refuge for calcifiers from ocean acidification. In the shallow nearshores of the western Kiel Bay (Baltic Sea), mussel and seagrass beds are interlacing, forming a mosaic habitat. Naturally, the diverse physiological activities of seagrasses and mussels are affected by seawater carbonate chemistry and they locally modify it in return. Calcification by shellfishes is sensitive to s...

  14. Seasonal habitat selection of the red deer (Cervus elaphus alxaicus in the Helan Mountains, China

    Directory of Open Access Journals (Sweden)

    Mingming Zhang

    2013-02-01

    Full Text Available We studied the seasonal habitat selection of the red deer, Cervus elaphus alxaicus Bobrinskii & Flerov, 1935, in the Helan Mountains, China, from December 2007 to December 2008. Habitat selection varied widely by season. Seasonal movements between high and low elevations were attributed to changes in forage availability, alpine topography, the arid climate of the Helan Mountains, and potential competition with blue sheep, Pseudois nayaur (Hodgson, 1833. The use of vegetation types varied seasonally according to food availability and ambient temperature. Red deer used montane coniferous forest and alpine shrub and meadow zones distributed above 2,000 m and 3,000 m in summer, alpine shrub and meadows above 3,000 m in autumn, being restricted to lower elevation habitats in spring and winter. The winter habitat of C. elaphus alxaicus was dominated by Ulmus glaucescens Franch. and Juglans regia Linnaeus, deciduous trees, and differed from the habitats selected by other subspecies of red deer. Cervus elaphus alxaicus preferred habitats with abundant vegetation coverage to open habitats in winter, but the reverse pattern was observed in summer and autumn. Red deer preferred gentle slopes (<10° but the use of slope gradient categories varied seasonally. Red deer avoidance of human disturbance in the Helan Mountains varied significantly by season. Information on red deer habitat selection can help understand the factors affecting seasonal movements and also support decision making in the management and conservation of red deer and their habitats.

  15. Selection indicates preference in diverse habitats: a ground-nesting bird (Charadrius melodus using reservoir shoreline.

    Directory of Open Access Journals (Sweden)

    Michael J Anteau

    Full Text Available Animals use proximate cues to select resources that maximize individual fitness. When animals have a diverse array of available habitats, those selected could give insights into true habitat preferences. Since the construction of the Garrison Dam on the Missouri River in North Dakota, Lake Sakakawea (SAK has become an important breeding area for federally threatened piping plovers (Charadrius melodus; hereafter plovers. We used conditional logistic regression to examine nest-site selection at fine scales (1, 3, and 10 m during summers 2006-2009 by comparing characteristics at 351 nests to those of 668 random sites within nesting territories. Plovers selected sites (1 m(2 that were lower than unused random sites, increasing the risk of nest inundation. Plovers selected nest sites that were flat, had little silt, and at least 1 cobble; they also selected for 3-m radius nest areas that were relatively flat and devoid of vegetation and litter. Ninety percent of nests had <38% coverage of silt and <10% slope at the site, and <15% coverage of vegetation or litter and <31% slope within the 3-m radius. Gravel was selected for at nest sites (11% median, but against in the area 10-m from the nest, suggesting plovers select for patches or strips of gravel. Although elevation is rarely evaluated in studies of ground-nesting birds, our results underscore its importance in habitat-selection studies. Relative to where plovers historically nested, habitat at SAK has more diverse topography, substrate composition, vegetation communities, and greater water-level fluctuations. Accordingly, our results provide an example of how habitat-selection results can be interpreted as habitat preferences because they are not influenced by desired habitats being scarce or absent. Further, our results will be useful for directing habitat conservation for plovers and interpreting other habitat-selection studies.

  16. Do Invasive Fire Ants Affect Habitat Selection within a Small Mammal Community?

    Directory of Open Access Journals (Sweden)

    Wendee N. Holtcamp

    2010-01-01

    Full Text Available Animals must balance foraging with the need to avoid predators and risky habitats that decrease their fitness, and at the same time they must cope with competitors vying for habitat and resources. We examined how habitat selection and population density of four native small mammals were altered by the presence of red imported fire ants (Solenopsis invicta. When population size was low, hispid cotton rats (Sigmodon hispidus and pigmy mice (Baiomys taylori as well as white-footed mice (Peromyscus leucopus used the “safe”, low fire ant habitat, as predicted by theories of density-dependent habitat selection. However, as fire ant population sizes expanded, cotton rats appeared to displace pigmy mice into the fire ant-dense grassland drainage while white-footed mice (Peromyscus leucopus displaced all the other small mammals from low fire ant forest/brushland habitat.

  17. Habitat selection for parasite-free space by hosts of parasitic cowbirds

    Science.gov (United States)

    Forsman, J.T.; Martin, T.E.

    2009-01-01

    Choice of breeding habitat can have a major impact on fitness. Sensitivity of habitat choice to environmental cues predicting reproductive success, such as density of harmful enemy species, should be favored by natural selection. Yet, experimental tests of this idea are in short supply. Brown-headed cowbirds Molothrus ater commonly reduce reproductive success of a wide diversity of birds by parasitizing their nests. We used song playbacks to simulate high cowbird density and tested whether cowbird hosts avoid such areas in habitat selection. Host species that made settlement decisions during manipulations were significantly less abundant in the cowbird treatment as a group. In contrast, hosts that settled before manipulations started and non-host species did not respond to treatments. These results suggest that hosts of cowbirds can use vocal cues to assess parasitism risk among potential habitat patches and avoid high risk habitats. This can affect community structure by affecting habitat choices of species with differential vulnerability.

  18. Niche segregation and habitat specialisation of harpacticoid copepods in a tropical seagrass bed

    OpenAIRE

    M. De Troch; FIERS, F; Vincx, M.

    2003-01-01

    Several harpacticoid copepod species are adapted to an epiphytic lifestyle. Previous studies on tropical seagrass meiofauna mainly focussed on the epiphytic communities and neglected the benthic component. The present study aims to document the benthic harpacticoid copepod communities sampled from different sediment depth horizons adjacent to five seagrass species in the intertidal and subtidal zone of a tropical seagrass bed (Gazi Bay, Kenya). Two benthic copepod communities could be identif...

  19. Wetland habitat selection by woodland caribou as characterized using the Alberta Wetland Inventory

    OpenAIRE

    W. Kent Brown; W. James Rettie; Bob Wynes; Kim Morton

    2011-01-01

    We examined habitat selection by woodland caribou (Rangifer tarandus caribou) in northwestern Alberta based on a wetland classification system developed for the Alberta Vegetation Inventory. Our two objectives were to describe caribou habitat use, and to assess the utility of the wetland classification system in land-use planning on caribou range. We used a geographical information system to overlay the locations of radio-collared caribou on the habitat map. Using a "moving-window" analysis o...

  20. Breeding season habitat selection by ferruginous pygmy owls glaucidium brasilianum in central Argentina

    OpenAIRE

    Campioni, Letizia; Sarasola, José Hernán; Santillán, M.; Reyes, M.M.

    2013-01-01

    Capsule The presence of Ferruginous Pygmy Owls Glaucidium brasilianum breeding in the xerophytic forest of Caldén Prosopis caldenia in central Argentina was slightly affected by forest maturity but neither by the structure of vegetation strata at the micro-habitat scale, nor by forest composition (mosaic of forest-grassland or shrubland) or proximity of water bodies at the macro-habitat scale. Aims To assess the habitat characteristics selected by Ferruginous Pygmy Owls during the breeding se...

  1. The impacts of intensity of human use on grizzly bear habitat selection

    OpenAIRE

    Ouren, Douglas S.; Garrott, Robert A.; Watts, Raymond D.; Lukins, William J.

    2003-01-01

    Problem Statement One of the major challenges to grizzly bear preservation in the greater Yellowstone area is the impact on grizzly bear habitat selection by various types and intensities of human activities. The most prevalent of these human activities is the presence and intensity of use of motorized transportation systems. These transportation systems provide increased access into grizzly bear habitat and thus increase the risk of mortality and dilute the effectiveness of their habitat (Br...

  2. Living on the edge: habitat selection of Hierophis viridiflavus

    Directory of Open Access Journals (Sweden)

    Stefano Scali

    2008-12-01

    Full Text Available We analysed habitat choices of H. viridiflavus in a continental area of northern Italy and compared our results with those reported from central Italy by other authors. We used two different field techniques, visual encounter surveys (VES and radio tracking (RT, and both pointed out a clear preference for edges, while uniform habitats (like mature woods or meadow were avoided. The same pattern of habitat use is documented for other whip snakes and can be related to the high thermal quality of edges, although other factors could not be ruled out (e.g., prey/shelters abundance. Nevertheless, other researches on Mediterranean populations do not show such a preference, suggesting that at lower latitude habitat thermal quality is not the main constraint and H. viridiflavus can behave as a habitat generalist. Finally, comparing the two field techniques, we find that VES partially overestimates the importance of edge use, suggesting that caution should be used about its utilization to obtain information in this kind of research.

  3. The relative importance of mangroves and seagrass beds as feeding habitats for resident and transient fishes from Florida and Belize:: evidence from dietary and stable isotope analyses

    Science.gov (United States)

    In the western Atlantic region, the contribution of mangrove food-sources to fish diets has been considered of more limited importance then previously expected due to their constant flooding and proximity to adjacent coastal habitats such as seagrass beds which provide potential ...

  4. Main seagrass beds and threats to their habitats in the coastal sea of South China

    Institute of Scientific and Technical Information of China (English)

    HUANG Xiaoping; LIU Sheng; HUANG Liangmin; LI Yinghong; XU Zhanzhou; FONG C W; HUANG Daojian; HAN Qiuying; HUANG Hui; TAN Yehui

    2006-01-01

    The distribution, species, biomass,productivity of main seagrasses and their suffered main threats are introduced and discussed in this paper based on the field surveys in the offshore areas of Guangdong, Guangxi and Hainan provinces.The seagrass beds distributed mainly in Liusha Bay,Donghai Island and Hailing Island of Guangdong Province; Hepu and Pearl Bay of Guangxi Zhuang Autonomous Region; Li'an Bay, Xincun Bay, Longwan Bay and Sanya Bay of Hainan Province and so on. The total area of seagrass beds in the coastal sea of South China is about 2400 ha. There are about 8 species, such as Halophila ovalis, Halodule uninervis,Halophila beccarii, Zostera japonica, Enhalus acoroides, Thalassia hemperichii, Ruppia martime and Cymodocea rotundata. These seagrasses have high biomass and productivity. However, they are subjected to some threats resulting from artificial and natural factors, especially anthropogenic causes,such as culture of shrimps and fishes, shellfish collection, fishing by means of poisons, electric power and explosives as well as trawling, artificial pollution,dredging channels, and typhoons natural disaster.

  5. Distinct Habitats Select Particular Bacterial Communities in Mangrove Sediments

    Directory of Open Access Journals (Sweden)

    Lidianne L. Rocha

    2016-01-01

    Full Text Available We investigated the relationship among environmental variables, composition, and structure of bacterial communities in different habitats in a mangrove located nearby to an oil exploitation area, aiming to retrieve the natural pattern of bacterial communities in this ecosystem. The T-RFLP analysis showed a high diversity of bacterial populations and an increase in the bacterial richness from habitats closer to the sea and without vegetation (S1 to habitats covered by Avicennia schaueriana (S2 and Rhizophora mangle (S3. Environmental variables in S1 and S2 were more similar than in S3; however, when comparing the bacterial compositions, S2 and S3 shared more OTUs between them, suggesting that the presence of vegetation is an important factor in shaping these bacterial communities. In silico analyses of the fragments revealed a high diversity of the class Gammaproteobacteria in the 3 sites, although in general they presented quite different bacterial composition, which is probably shaped by the specificities of each habitat. This study shows that microhabitats inside of a mangrove ecosystem harbor diverse and distinct microbiota, reinforcing the need to conserve these ecosystems as a whole.

  6. Habitat selection by chironomid larvae: fast growth requires fast food

    NARCIS (Netherlands)

    Haas, de E.M.; Wagner, C.; Koelmans, A.A.; Kraak, M.H.S.; Admiraal, W.

    2006-01-01

    1. Sediments have been considered as a habitat, a cover from predators and a source of food, but also as a source of potential toxic compounds. Therefore, the choice of a suitable substrate is essential for the development of chironomids. 2. For the midge Chironomus riparius (Meigen 1804) the growth

  7. Distinct Habitats Select Particular Bacterial Communities in Mangrove Sediments.

    Science.gov (United States)

    Rocha, Lidianne L; Colares, Geórgia B; Nogueira, Vanessa L R; Paes, Fernanda A; Melo, Vânia M M

    2016-01-01

    We investigated the relationship among environmental variables, composition, and structure of bacterial communities in different habitats in a mangrove located nearby to an oil exploitation area, aiming to retrieve the natural pattern of bacterial communities in this ecosystem. The T-RFLP analysis showed a high diversity of bacterial populations and an increase in the bacterial richness from habitats closer to the sea and without vegetation (S1) to habitats covered by Avicennia schaueriana (S2) and Rhizophora mangle (S3). Environmental variables in S1 and S2 were more similar than in S3; however, when comparing the bacterial compositions, S2 and S3 shared more OTUs between them, suggesting that the presence of vegetation is an important factor in shaping these bacterial communities. In silico analyses of the fragments revealed a high diversity of the class Gammaproteobacteria in the 3 sites, although in general they presented quite different bacterial composition, which is probably shaped by the specificities of each habitat. This study shows that microhabitats inside of a mangrove ecosystem harbor diverse and distinct microbiota, reinforcing the need to conserve these ecosystems as a whole. PMID:26989418

  8. Habitat selection and behaviour of a reintroduced passerine: linking experimental restoration, behaviour and habitat ecology.

    Directory of Open Access Journals (Sweden)

    Victoria A Bennett

    Full Text Available Habitat restoration can play an important role in recovering functioning ecosystems and improving biodiversity. Restoration may be particularly important in improving habitat prior to species reintroductions. We reintroduced seven brown treecreeper (Climacteris picumnus social groups into two nature reserves in the Australian Capital Territory in south-eastern Australia. This study provided a unique opportunity to understand the interactions between restoration ecology, behavioural ecology and habitat ecology. We examined how experimental restoration treatments (addition of coarse woody debris, variations in ground vegetation cover and nest box installation influenced the behaviour and microhabitat use of radio-tracked individuals to evaluate the success of restoration treatments. The addition of coarse woody debris benefited the brown treecreeper through increasing the probability of foraging on a log or on the ground. This demonstrated the value of using behaviour as a bio-indicator for restoration success. Based on previous research, we predicted that variations in levels of ground vegetation cover would influence behaviour and substrate use, particularly that brown treecreepers would choose sites with sparse ground cover because this allows better access to food and better vigilance for predators. However, there was little effect of this treatment, which was likely influenced by the limited overall use of the ground layer. There was also little effect of nest boxes on behaviour or substrate use. These results somewhat confound our understanding of the species based on research from extant populations. Our results also have a significant impact regarding using existing knowledge on a species to inform how it will respond to reintroduction and habitat restoration. This study also places great emphasis on the value of applying an experimental framework to ecological restoration, particularly when reintroductions produce unexpected outcomes.

  9. Habitat selection and behaviour of a reintroduced passerine: linking experimental restoration, behaviour and habitat ecology.

    Science.gov (United States)

    Bennett, Victoria A; Doerr, Veronica A J; Doerr, Erik D; Manning, Adrian D; Lindenmayer, David B; Yoon, Hwan-Jin

    2013-01-01

    Habitat restoration can play an important role in recovering functioning ecosystems and improving biodiversity. Restoration may be particularly important in improving habitat prior to species reintroductions. We reintroduced seven brown treecreeper (Climacteris picumnus) social groups into two nature reserves in the Australian Capital Territory in south-eastern Australia. This study provided a unique opportunity to understand the interactions between restoration ecology, behavioural ecology and habitat ecology. We examined how experimental restoration treatments (addition of coarse woody debris, variations in ground vegetation cover and nest box installation) influenced the behaviour and microhabitat use of radio-tracked individuals to evaluate the success of restoration treatments. The addition of coarse woody debris benefited the brown treecreeper through increasing the probability of foraging on a log or on the ground. This demonstrated the value of using behaviour as a bio-indicator for restoration success. Based on previous research, we predicted that variations in levels of ground vegetation cover would influence behaviour and substrate use, particularly that brown treecreepers would choose sites with sparse ground cover because this allows better access to food and better vigilance for predators. However, there was little effect of this treatment, which was likely influenced by the limited overall use of the ground layer. There was also little effect of nest boxes on behaviour or substrate use. These results somewhat confound our understanding of the species based on research from extant populations. Our results also have a significant impact regarding using existing knowledge on a species to inform how it will respond to reintroduction and habitat restoration. This study also places great emphasis on the value of applying an experimental framework to ecological restoration, particularly when reintroductions produce unexpected outcomes. PMID:23349923

  10. Specializing on vulnerable habitat: Acropora selectivity among damselfish recruits and the risk of bleaching-induced habitat loss

    Science.gov (United States)

    Bonin, M. C.

    2012-03-01

    Coral reef habitats are increasingly being degraded and destroyed by a range of disturbances, most notably climate-induced coral bleaching. Habitat specialists, particularly those associated with susceptible coral species, are clearly among the most vulnerable to population decline or extinction. However, the degree of specialization on coral microhabitats is still unclear for one of the most ubiquitous, abundant and well studied of coral reef fish families—the damselfishes (Pomacentridae). Using high taxonomic resolution surveys of microhabitat use and availability, this study provides the first species-level description of patterns of Acropora selectivity among recruits of 10 damselfish species in order to determine their vulnerability to habitat degradation. In addition, surveys of the bleaching susceptibility of 16 branching coral species revealed which preferred recruitment microhabitats are at highest risk of decline as a result of chronic coral bleaching. Four species (i.e., Chrysiptera parasema, Pomacentrus moluccensis, Dascyllus melanurus and Chromis retrofasciata) were identified as highly vulnerable because they used only branching hard corals as recruitment habitat and primarily associated with only 2-4 coral species. The bleaching surveys revealed that five species of Acropora were highly susceptible to bleaching, with more than 50% of colonies either severely bleached or already dead. These highly susceptible corals included two of the preferred microhabitats of the specialist C. parasema and represented a significant proportion of its total recruitment microhabitat. In contrast, highly susceptible corals were rarely used by another specialist, P. moluccensis, suggesting that this species faces a lower risk of bleaching-induced habitat loss compared to C. parasema. As degradation to coral reef habitats continues, specialists will increasingly be forced to use alternative recruitment microhabitats, and this is likely to reduce population

  11. Daytime habitat selection for juvenile parr brown trout (Salmo trutta in small lowland streams

    Directory of Open Access Journals (Sweden)

    Conallin J.

    2014-03-01

    Full Text Available Physical habitat is important in determining the carrying capacity of juvenile brown trout, and within freshwater management. Summer daytime physical habitat selection for the parr lifestage (7–20 cm juvenile brown trout (Salmo trutta was assessed in 6 small lowland streams. Habitat preference was determined for the four variables; water velocity, water depth, substrate and cover, and the preferences for physical habitat selection were expressed in terms of habitat suitability indices (HSI’s. The statistical confidence of HSI’s was evaluated using power analysis. It was found that a minimum of 22 fish observations was needed to have statistical confidence in the HSIs for water depth, and a minimum of 92 fish observations for water velocity during daytime summer conditions. Generally parr were utilising the deeper habitats, indicating preference for deeper water. Cover was also being selected for at all sites, but selection was inconsistent among sites for the variables substrate and velocity. The results indicate that during daytime summer conditions water depth is a significant variable for parr habitat selection in these small lowland streams, with cover also being important. Therefore, daytime refugia may be a critical limiting factor for parr in small lowland streams, and important for stream management actions under the Water Framework Directive.

  12. Daytime habitat selection for juvenile parr brown trout (Salmo trutta) in small lowland streams

    DEFF Research Database (Denmark)

    Conallin, J.; Boegh, E.; Olsen, M.;

    2014-01-01

    was determined for the four variables; water velocity, water depth, substrate and cover, and the preferences for physical habitat selection were expressed in terms of habitat suitability indices (HSI's). The statistical confidence of HSI's was evaluated using power analysis. It was found that a minimum of 22...... fish observations was needed to have statistical confidence in the HSIs for water depth, and a minimum of 92 fish observations for water velocity during daytime summer conditions. Generally parr were utilising the deeper habitats, indicating preference for deeper water. Cover was also being selected...... for at all sites, but selection was inconsistent among sites for the variables substrate and velocity. The results indicate that during daytime summer conditions water depth is a significant variable for parr habitat selection in these small lowland streams, with cover also being important. Therefore...

  13. Selecting the most adequate bedding material for broiler production in Brazil

    Directory of Open Access Journals (Sweden)

    RG Garcia

    2012-06-01

    Full Text Available Broiler chicken production is widely dispersed across the globe, and one important issue for growers is the selection of adequate bedding material, as the availability and price of substrates varies among countries and regions within a same country. This study aimed at applying a multiple criteria analysis approach for the selection of the most appropriate bedding material for broiler production. Based on field research data and growers' experience, the most desirable characteristics of a litter material were chosen as the main criteria. The selected materials were wood shavings, rice husks, chopped Napier grass (Pennisetum pupureum, 50% sugar cane bagasse (Saccharum L. plus 50% wood shavings, 50% sugar cane bagasse (Saccharum L. plus 50% rice husks, and pure sugar cane bagasse (Saccharum L.. The analytical hierarchy process (AHP was applied for selecting the most suitable bedding material. Validation was performed using data from previous studies carried out in central-western Brazil on the effects of different types of bedding material on broiler carcass quality. Considering the selected criteria, several bedding materials were tested and ranked, and the results showed that wood-shavings litter was the best option (weight = 0.28, followed by rice husks (weight = 0.24. All other tested alternatives presented lower scores and were, therefore, not considered for use. The AHP approach was found to be an efficient tool to select the most appropriate litter material under specific scenarios.

  14. Seasonal habitat selection of the red deer (Cervus elaphus alxaicus) in the Helan Mountains, China

    OpenAIRE

    Mingming Zhang; Zhensheng Liu; Liwei Teng

    2013-01-01

    We studied the seasonal habitat selection of the red deer, Cervus elaphus alxaicus Bobrinskii & Flerov, 1935, in the Helan Mountains, China, from December 2007 to December 2008. Habitat selection varied widely by season. Seasonal movements between high and low elevations were attributed to changes in forage availability, alpine topography, the arid climate of the Helan Mountains, and potential competition with blue sheep, Pseudois nayaur (Hodgson, 1833). The use of vegetation types varied sea...

  15. Distribution and characteristics of marine habitats in a subpolar bay based on hydroacoustics and bed shear stress estimates—Potter Cove, King George Island, Antarctica

    Science.gov (United States)

    Wölfl, Anne-Cathrin; Lim, Chai Heng; Hass, H. Christian; Lindhorst, Sebastian; Tosonotto, Gabriela; Lettmann, Karsten Alexander; Kuhn, Gerhard; Wolff, Jörg-Olaf; Abele, Doris

    2014-10-01

    Marine habitats worldwide are increasingly pressurized by climate change, especially along the Antarctic Peninsula. Well-studied areas in front of rapidly retreating tidewater glaciers like Potter Cove are representative for similar coastal environments and, therefore, shed light on habitat formation and development on not only a local but also regional scale. The objective of this study was to provide insights into habitat distribution in Potter Cove, King George Island, Antarctica, and to evaluate the associated environmental processes. Furthermore, an assessment concerning the future development of the habitats is provided. To describe the seafloor habitats in Potter Cove, an acoustic seabed discrimination system (RoxAnn) was used in combination with underwater video images and sediment samples. Due to the absence of wave and current measurements in the study area, bed shear stress estimates served to delineate zones prone to sediment erosion. On the basis of the investigations, two habitat classes were identified in Potter Cove, namely soft-sediment and stone habitats that, besides influences from sediment supply and coastal morphology, are controlled by sediment erosion. A future expansion of the stone habitat is predicted if recent environmental change trends continue. Possible implications for the Potter Cove environment, and other coastal ecosystems under similar pressure, include changes in biomass and species composition.

  16. Invariant polar bear habitat selection during a period of sea ice loss.

    Science.gov (United States)

    Wilson, Ryan R; Regehr, Eric V; Rode, Karyn D; St Martin, Michelle

    2016-08-17

    Climate change is expected to alter many species' habitat. A species' ability to adjust to these changes is partially determined by their ability to adjust habitat selection preferences to new environmental conditions. Sea ice loss has forced polar bears (Ursus maritimus) to spend longer periods annually over less productive waters, which may be a primary driver of population declines. A negative population response to greater time spent over less productive water implies, however, that prey are not also shifting their space use in response to sea ice loss. We show that polar bear habitat selection in the Chukchi Sea has not changed between periods before and after significant sea ice loss, leading to a 75% reduction of highly selected habitat in summer. Summer was the only period with loss of highly selected habitat, supporting the contention that summer will be a critical period for polar bears as sea ice loss continues. Our results indicate that bears are either unable to shift selection patterns to reflect new prey use patterns or that there has not been a shift towards polar basin waters becoming more productive for prey. Continued sea ice loss is likely to further reduce habitat with population-level consequences for polar bears. PMID:27534959

  17. A fluidized bed selective emitter system driven by a non-premixed burner

    Science.gov (United States)

    Ortabasi, U.; Lund, K. O.; Seshadri, K.

    1996-02-01

    One of the key priorities in the development of Thermophotovoltaic power technology is a highly efficient heat-source/emitter system that is robust and stable. This paper describes a tightly coupled burner/selective emitter combination that integrates two novel concepts that are now under development: A fluidized bed emitter that consists of hollow, submillimeter spheres as the sources of radiant energy and a non-premixed, self regulating burner. The rationale behind the proposed system is to combine the unique intrinsic features of both concepts to provide the TPV community with an enabling technology. The fluidized bed provides excellent heat transfer, temperature uniformity, high radiant power density, reduced substrate and combustion background, robustness, thermal shock resistance, minimal contamination, and long operational life. The paper discusses a fluidized bed system that consists of selectively emitting, hollow Ho-YAG spheres with 500 micron diameter and 10-100 micron shell thickness operating at 1500 K. Key issues related to heat transfer and radiation transport in the fluidized bed are analyzed. The collective emitter efficiency and power density of a fluidized bed are discussed. The non-premixed burner achieves very high temperatures, has a low emission in toxic byproducts, provides self regulating stability, eliminates flashback hazards, and is operable with hydrogen. The paper concludes with a description of a complete fluidized bed TPV system including an elliptic/parabolic transfer optics and a photovoltaic cavity converter that boosts the flux density received by the photovoltaic cells.

  18. Raising distillate selectivity and catalyst life time in Fischer-Tropsch synthesis by using a novel dual-bed reactor

    International Nuclear Information System (INIS)

    In a novel dual bed reactor Fischer-Tropsch synthesis was studied by using two diff rent cobalt catalysts. An alkali-promoted cobalt catalyst was used in the first bed of a fixed-bed reactor followed by a Raiment promoted cobalt catalyst in the second bed. The activity, product selectivity and accelerated deactivation of the system were assessed and compared with a conventional single bed reactor system. The methane selectivity in the dual-bed reactor was about 18.9% less compared to that of the single-bed reactor. The C5+ selectivity for the dual-bed reactor was 10.9% higher than that of the single-bed reactor. Accelerated deactivation of the catalysts in the dual-bed reactor was 42% lower than that of the single-bed reactor. It was revealed that the amount of catalysts activity recovery after regeneration at 400degC in the dual-bed system is higher than that of the single-bed system

  19. Landscape effects on mallard habitat selection at multiple spatial scales during the non-breeding period

    Science.gov (United States)

    Beatty, William S.; Webb, Elisabeth B.; Kesler, Dylan C.; Raedeke, Andrew H.; Naylor, Luke W.; Humburg, Dale D.

    2014-01-01

    Previous studies that evaluated effects of landscape-scale habitat heterogeneity on migratory waterbird distributions were spatially limited and temporally restricted to one major life-history phase. However, effects of landscape-scale habitat heterogeneity on long-distance migratory waterbirds can be studied across the annual cycle using new technologies, including global positioning system satellite transmitters. We used Bayesian discrete choice models to examine the influence of local habitats and landscape composition on habitat selection by a generalist dabbling duck, the mallard (Anas platyrhynchos), in the midcontinent of North America during the non-breeding period. Using a previously published empirical movement metric, we separated the non-breeding period into three seasons, including autumn migration, winter, and spring migration. We defined spatial scales based on movement patterns such that movements >0.25 and 30.00 km were classified as relocation scale. Habitat selection at the local scale was generally influenced by local and landscape-level variables across all seasons. Variables in top models at the local scale included proximities to cropland, emergent wetland, open water, and woody wetland. Similarly, variables associated with area of cropland, emergent wetland, open water, and woody wetland were also included at the local scale. At the relocation scale, mallards selected resource units based on more generalized variables, including proximity to wetlands and total wetland area. Our results emphasize the role of landscape composition in waterbird habitat selection and provide further support for local wetland landscapes to be considered functional units of waterbird conservation and management.

  20. Seasonal and diel habitat selection by bluegills in a shallow natural lake

    Science.gov (United States)

    Paukert, C.P.; Willis, D.W.

    2002-01-01

    Habitat use by bluegill Lepomis macrochirus may be dictated by the avoidance of predators and the availability of prey. Previous work suggests that bluegills large enough to avoid predators will select habitats based on foraging profitability. However, these studies focused on smaller fish (200 mm total length [TL]) bluegills in a shallow (mean depth = 1.2 m), 332-ha, natural lake (Pelican Lake, Nebraska) with both emergent and submergent vegetation distributed throughout. A total of 78 bluegills (200-273 mm TL) were implanted with radio transmitters and relocated daily for 6 d per month (April-September); up to 20 of the tagged fish were relocated every 2 h for a 24-h period once each month. Regardless of diel period, bluegills used open-water, emergent vegetation, submergent vegetation, and mixed emergent - submergent vegetation habitat types in similar proportions. During April, June, and July, male bluegills positively selected emergent vegetation, whereas female bluegills showed no vegetation selection preference during any month. Throughout the study period, bluegills never avoided open-water habitats, suggesting that larger individuals may continue to use open-water habitats in proportion to their availability. In addition, emergent vegetation appeared to be important, particularly for male bluegills. Although the mechanism for the positive selection of emergent vegetation by males was unclear, the protection or enhancement of such habitats may facilitate the preservation of quality bluegill populations in shallow lakes.

  1. Habitat selection and post-release movement of reintroduced brown treecreeper individuals in restored temperate woodland.

    Directory of Open Access Journals (Sweden)

    Victoria A Bennett

    Full Text Available It is essential to choose suitable habitat when reintroducing a species into its former range. Habitat quality may influence an individual's dispersal decisions and also ultimately where they choose to settle. We examined whether variation in habitat quality (quantified by the level of ground vegetation cover and the installation of nest boxes influenced the movement, habitat choice and survival of a reintroduced bird species. We experimentally reintroduced seven social groups (43 individuals of the brown treecreeper (Climacteris picumnus into two nature reserves in south-eastern Australia. We radio-tracked 18 brown treecreepers from release in November 2009 until February 2010. We observed extensive movements by individuals irrespective of the release environment or an individual's gender. This indicated that individuals were capable of dispersing and actively selecting optimum habitat. This may alleviate pressure on wildlife planners to accurately select the most optimum release sites, so long as the species' requirements are met. There was significant variation in movement between social groups, suggesting that social factors may be a more important influence on movement than habitat characteristics. We found a significant effect of ground vegetation cover on the likelihood of settlement by social groups, with high rates of settlement and survival in dry forests, rather than woodland (where the species typically resides, which has implications for the success of woodland restoration. However, overall the effects of variation in habitat quality were not as strong as we had expected, and resulted in some unpredicted effects such as low survival and settlement in woodland areas with medium levels of ground vegetation cover. The extensive movement by individuals and unforeseen effects of habitat characteristics make it difficult to predict the outcome of reintroductions, the movement behaviour and habitat selection of reintroduced individuals

  2. Habitat selection and post-release movement of reintroduced brown treecreeper individuals in restored temperate woodland.

    Science.gov (United States)

    Bennett, Victoria A; Doerr, Veronica A J; Doerr, Erik D; Manning, Adrian D; Lindenmayer, David B; Yoon, Hwan-Jin

    2012-01-01

    It is essential to choose suitable habitat when reintroducing a species into its former range. Habitat quality may influence an individual's dispersal decisions and also ultimately where they choose to settle. We examined whether variation in habitat quality (quantified by the level of ground vegetation cover and the installation of nest boxes) influenced the movement, habitat choice and survival of a reintroduced bird species. We experimentally reintroduced seven social groups (43 individuals) of the brown treecreeper (Climacteris picumnus) into two nature reserves in south-eastern Australia. We radio-tracked 18 brown treecreepers from release in November 2009 until February 2010. We observed extensive movements by individuals irrespective of the release environment or an individual's gender. This indicated that individuals were capable of dispersing and actively selecting optimum habitat. This may alleviate pressure on wildlife planners to accurately select the most optimum release sites, so long as the species' requirements are met. There was significant variation in movement between social groups, suggesting that social factors may be a more important influence on movement than habitat characteristics. We found a significant effect of ground vegetation cover on the likelihood of settlement by social groups, with high rates of settlement and survival in dry forests, rather than woodland (where the species typically resides), which has implications for the success of woodland restoration. However, overall the effects of variation in habitat quality were not as strong as we had expected, and resulted in some unpredicted effects such as low survival and settlement in woodland areas with medium levels of ground vegetation cover. The extensive movement by individuals and unforeseen effects of habitat characteristics make it difficult to predict the outcome of reintroductions, the movement behaviour and habitat selection of reintroduced individuals, particularly when

  3. Resampling method for applying density-dependent habitat selection theory to wildlife surveys.

    Directory of Open Access Journals (Sweden)

    Olivia Tardy

    Full Text Available Isodar theory can be used to evaluate fitness consequences of density-dependent habitat selection by animals. A typical habitat isodar is a regression curve plotting competitor densities in two adjacent habitats when individual fitness is equal. Despite the increasing use of habitat isodars, their application remains largely limited to areas composed of pairs of adjacent habitats that are defined a priori. We developed a resampling method that uses data from wildlife surveys to build isodars in heterogeneous landscapes without having to predefine habitat types. The method consists in randomly placing blocks over the survey area and dividing those blocks in two adjacent sub-blocks of the same size. Animal abundance is then estimated within the two sub-blocks. This process is done 100 times. Different functional forms of isodars can be investigated by relating animal abundance and differences in habitat features between sub-blocks. We applied this method to abundance data of raccoons and striped skunks, two of the main hosts of rabies virus in North America. Habitat selection by raccoons and striped skunks depended on both conspecific abundance and the difference in landscape composition and structure between sub-blocks. When conspecific abundance was low, raccoons and striped skunks favored areas with relatively high proportions of forests and anthropogenic features, respectively. Under high conspecific abundance, however, both species preferred areas with rather large corn-forest edge densities and corn field proportions. Based on random sampling techniques, we provide a robust method that is applicable to a broad range of species, including medium- to large-sized mammals with high mobility. The method is sufficiently flexible to incorporate multiple environmental covariates that can reflect key requirements of the focal species. We thus illustrate how isodar theory can be used with wildlife surveys to assess density-dependent habitat selection

  4. Resampling method for applying density-dependent habitat selection theory to wildlife surveys.

    Science.gov (United States)

    Tardy, Olivia; Massé, Ariane; Pelletier, Fanie; Fortin, Daniel

    2015-01-01

    Isodar theory can be used to evaluate fitness consequences of density-dependent habitat selection by animals. A typical habitat isodar is a regression curve plotting competitor densities in two adjacent habitats when individual fitness is equal. Despite the increasing use of habitat isodars, their application remains largely limited to areas composed of pairs of adjacent habitats that are defined a priori. We developed a resampling method that uses data from wildlife surveys to build isodars in heterogeneous landscapes without having to predefine habitat types. The method consists in randomly placing blocks over the survey area and dividing those blocks in two adjacent sub-blocks of the same size. Animal abundance is then estimated within the two sub-blocks. This process is done 100 times. Different functional forms of isodars can be investigated by relating animal abundance and differences in habitat features between sub-blocks. We applied this method to abundance data of raccoons and striped skunks, two of the main hosts of rabies virus in North America. Habitat selection by raccoons and striped skunks depended on both conspecific abundance and the difference in landscape composition and structure between sub-blocks. When conspecific abundance was low, raccoons and striped skunks favored areas with relatively high proportions of forests and anthropogenic features, respectively. Under high conspecific abundance, however, both species preferred areas with rather large corn-forest edge densities and corn field proportions. Based on random sampling techniques, we provide a robust method that is applicable to a broad range of species, including medium- to large-sized mammals with high mobility. The method is sufficiently flexible to incorporate multiple environmental covariates that can reflect key requirements of the focal species. We thus illustrate how isodar theory can be used with wildlife surveys to assess density-dependent habitat selection over large

  5. Maladaptive habitat selection of a migratory passerine bird in a human-modified landscape.

    Directory of Open Access Journals (Sweden)

    Franck A Hollander

    Full Text Available In human-altered environments, organisms may preferentially settle in poor-quality habitats where fitness returns are lower relative to available higher-quality habitats. Such ecological trapping is due to a mismatch between the cues used during habitat selection and the habitat quality. Maladaptive settlement decisions may occur when organisms are time-constrained and have to rapidly evaluate habitat quality based on incomplete knowledge of the resources and conditions that will be available later in the season. During a three-year study, we examined settlement decision-making in the long-distance migratory, open-habitat bird, the Red-backed shrike (Lanius collurio, as a response to recent land-use changes. In Northwest Europe, the shrikes typically breed in open areas under a management regime of extensive farming. In recent decades, Spruce forests have been increasingly managed with large-size cutblocks in even-aged plantations, thereby producing early-successional vegetation areas that are also colonised by the species. Farmland and open areas in forests create mosaics of two different types of habitats that are now occupied by the shrikes. We examined redundant measures of habitat preference (order of settlement after migration and distribution of dominant individuals and several reproductive performance parameters in both habitat types to investigate whether habitat preference is in line with habitat quality. Territorial males exhibited a clear preference for the recently created open areas in forests with higher-quality males settling in this habitat type earlier. Reproductive performance was, however, higher in farmland, with higher nest success, offspring quantity, and quality compared to open areas in forests. The results showed strong among-year consistency and we can therefore exclude a transient situation. This study demonstrates a case of maladaptive habitat selection in a farmland bird expanding its breeding range to human

  6. Monitoring and mapping selected riparian habitat along the lower Snake River

    Energy Technology Data Exchange (ETDEWEB)

    Downs, J. L; Tiller, B. L [Pacific Northwest Lab., Richland, WA (United States); Witter, M. [Shannon and Wilson, Inc., Seattle, WA (United States). Geotechnical and Environmental Consultants, Seattle, Washington (United States); Mazaika, R. [Corps of Engineers, Portland, OR (United States)

    1996-01-01

    Studies in this document were initiated to establish baseline information on riparian and wetland habitat conditions at the areas studied under the current reservoir operations on the lower Snake River. Two approaches were used to assess habitat at 28 study sites selected on the four pools on the lower Snake River. These areas all contribute significant riparian habitat along the river, and several of these areas are designated habitat management units. At 14 of the 28 sites, we monitored riparian habitat on three dates during the growing season to quantify vegetation abundance and composition along three transects: soil nutrients, moisture, and pH and water level and pH. A second approach involved identifying any differences in the extent and amount of riparian/wetland habitat currently found at the study areas from that previously documented. We used both ground and boat surveys to map and classify the changes in vegetative cover along the shoreline at the 14 monitoring sites and at 14 additional sites along the lower Snake selected to represent various riparian/wetland habitat conditions. Results of these mapping efforts are compared with maps of cover types previously generated using aerial photography taken in 1987.

  7. Habitat selection of stone and starry flounders in an estuary in relation to feeding and survival

    Science.gov (United States)

    Tomiyama, Takeshi; Omori, Michio

    2008-09-01

    Juveniles of both stone flounder Platichthys bicoloratus and starry flounder Platichthys stellatus utilize estuaries as nursery grounds. To understand their habitat selection and the functions of habitats such as food supply, we defined the seasonal distribution of recently settled fish of these species in shallow nursery areas and investigated their feeding habits in the Natori River estuary, Japan. Distribution of stone flounder was limited to the lower estuary (fish of both stone and starry flounders fed mainly on the bivalve siphons. These results indicate that habitat selections of juvenile stone and starry flounders enable utilization of preferred prey and predator avoidance, respectively, and that non-overlap of these species' habitats results in avoidance of inter-specific competition for food between these two species.

  8. Combining information from range use and habitat selection: sex-specific spatial responses to habitat fragmentation in tawny owls Strix aluco

    DEFF Research Database (Denmark)

    Sunde, Peter; Redpath, Stephen M.

    2006-01-01

    How individuals respond to habitat heterogeneity is usually measured as variation in range size and by ranking the relative importance of habitat types (habitat selection). The combined effect of how individuals incorporate different habitat types in their home ranges and allocate their time budget...... between them is rarely derived. Additionally, when home range size varies between individuals, habitat selection analyses might be flawed if foraging decisions are based on variation in absolute rather than proportional availability. We investigated the suitability of standard analytical approaches...... by measuring the spatial responses of tawny owls to habitat fragmentation. These owls inhabited woodland of various sizes, representing a fragmentation gradient from open farmland with small, isolated woodland patches, to continuous woodland within their home ranges. In 17 territories within open farmland...

  9. ECONOMIC ANALYSIS OF SELECTED ADSORPTION BEDS USED FOR WATER TREATMENT

    Directory of Open Access Journals (Sweden)

    Iwona Skoczko

    2016-02-01

    Full Text Available In the paper an economic analysis of the sorption deposits used for water purification was performed. Such masses of carbon as Organosorb 10 deposit, Norit ROW 0.8 Supra deposit, Hydroantracyt N deposit and K110 deposit were selected. The economic substantiation for the selection of specific deposits was based on the purchase cost of filter deposits, the environmental fee for water intake, the cost of equipment to aerate water, the cost of chemicals for deposits regeneration, the cost of the dosing pump reagents for regeneration generated during the process of adsorption using each of the deposits selected to the analysis. K110 deposit turned out to be the cheapest in the exploitation and Norit ROW 0.8 Supra was most expensive. The operating costs of the adsorption deposits depend mainly on the purchase of the adsorbent and the speed of adsorption. Moreover, environmental fee for water intake constitutes a significant share in the costs of exploitation of carbon deposits , which is greater than the deposit costs.

  10. Space Use and Habitat Selection by Resident and Transient Coyotes (Canis latrans)

    OpenAIRE

    Joseph W. Hinton; van Manen, Frank T; Chamberlain, Michael J.

    2015-01-01

    Little information exists on coyote (Canis latrans) space use and habitat selection in the southeastern United States and most studies conducted in the Southeast have been carried out within small study areas (e.g., ≤1,000 km2). Therefore, studying the placement, size, and habitat composition of coyote home ranges over broad geographic areas could provide relevant insights regarding how coyote populations adjust to regionally varying ecological conditions. Despite an increasing number of stud...

  11. Habitat Selection by Eld’s Deer following Relocation to a Patchy Landscape

    OpenAIRE

    Duo Pan; Yan-Ling Song; Zhi-Gao Zeng; Bravery, Benjamin D.

    2014-01-01

    An emerging issue in wildlife conservation is the re-establishment of viable populations of endangered species in suitable habitats. Here, we studied habitat selection by a population of Hainan Eld's deer (Cervus eldi) relocated to a patchy landscape of farmland and forest. Hainan Eld's deer were pushed to the brink of extinction in the 1970s, but their population expanded rapidly from 26 to more than 1000 individuals by 2003 through effective reserve protection. As part of a wider relocation...

  12. Redd Site Selection and Spawning Habitat Use by Fall Chinook Salmon, Hanford Reach, Columbia River : Final Report 1995 - 1998.

    Energy Technology Data Exchange (ETDEWEB)

    Geist, David R.

    1999-05-01

    year to year. The tendency to spawn in clusters suggests fall chinook salmon's use of spawning habitat is highly selective. Hydraulic characteristics of the redd clusters were significantly different than the habitat surrounding them. Velocity and lateral slope of the river bottom were the most important habitat variables in predicting redd site selection. While these variables explained a large proportion of the variance in redd site selection (86 to 96%), some unmeasured factors still accounted for a small percentage of actual spawning site selection. Chapter three describes the results from an investigation into the hyporheic characteristics of the two spawning areas studied in chapter two. This investigation showed that the magnitude and chemical characteristics of hyporheic discharge were different between and within two spawning areas. Apparently, fall chinook salmon used chemical and physical cues from the discharge to locate spawning areas. Finally, chapter four describes a unique method that was developed to install piezometers into the cobble bed of the Columbia River.

  13. Wetland habitat selection by woodland caribou as characterized using the Alberta Wetland Inventory

    Directory of Open Access Journals (Sweden)

    W. Kent Brown

    2011-04-01

    Full Text Available We examined habitat selection by woodland caribou (Rangifer tarandus caribou in northwestern Alberta based on a wetland classification system developed for the Alberta Vegetation Inventory. Our two objectives were to describe caribou habitat use, and to assess the utility of the wetland classification system in land-use planning on caribou range. We used a geographical information system to overlay the locations of radio-collared caribou on the habitat map. Using a "moving-window" analysis of habitat availability, we examined patterns of habitat selection by 16 individual female caribou during five seasons annually over two years. We did not detect significant differences in habitat selection patterns among seasons. Caribou showed significant preferences for both bogs and fens with low to moderate tree cover relative to marshes, uplands, heavily forested wetlands, water, and areas of human use. The wetland classification system appears to have value for broad-scale planning of industrial activity on caribou range. More-detailed descriptions of vegetation, especially understory species, are required to refine this system for operational-level forest harvest planning.

  14. Winter habitat selection of mule deer before and during development of a natural gas field

    Science.gov (United States)

    Sawyer, H.; Nielson, R.M.; Lindzey, F.; McDonald, L.L.

    2006-01-01

    Increased levels of natural gas exploration, development, and production across the Intermountain West have created a variety of concerns for mule deer (Odocoileus hemionus) populations, including direct habitat loss to road and well-pad construction and indirect habitat losses that may occur if deer use declines near roads or well pads. We examined winter habitat selection patterns of adult female mule deer before and during the first 3 years of development in a natural gas field in western Wyoming. We used global positioning system (GPS) locations collected from a sample of adult female mule deer to model relative frequency or probability of use as a function of habitat variables. Model coefficients and predictive maps suggested mule deer were less likely to occupy areas in close proximity to well pads than those farther away. Changes in habitat selection appeared to be immediate (i.e., year 1 of development), and no evidence of well-pad acclimation occurred through the course of the study; rather, mule deer selected areas farther from well pads as development progressed. Lower predicted probabilities of use within 2.7 to 3.7 km of well pads suggested indirect habitat losses may be substantially larger than direct habitat losses. Additionally, some areas classified as high probability of use by mule deer before gas field development changed to areas of low use following development, and others originally classified as low probability of use were used more frequently as the field developed. If areas with high probability of use before development were those preferred by the deer, observed shifts in their distribution as development progressed were toward less-preferred and presumably less-suitable habitats.

  15. Habitat structure is more important than nutrient supply in modifying mussel bed assemblage in an upwelling area of the Peruvian coast

    Science.gov (United States)

    Firstater, Fausto N.; Hidalgo, Fernando J.; Lomovasky, Betina J.; Ramos, Elmer; Gamero, Patricia; Iribarne, Oscar O.

    2011-06-01

    Upwelling intensity modifies coastal primary production and influences individual traits of habitat-forming species. Along the Peruvian coast, beds of the mytilid Perumytilus purpuratus provide structurally complex habitats that harbour many organisms. We predict that in the nutrient-rich system of Central Peru, the modification of structural complexity would have stronger effects on the Perumytilus community than nutrient addition. We experimentally examined the effects of nutrient addition on the Perumytilus-dominated assemblage and we evaluated the potential effect of varying shell size on the Perumytilus-dominated assemblage. Nutrient addition to the mussel bed with slow-release fertilizers caused no changes in the total macro- and microalgal biomass and did not affect abundances or composition of the assemblage. To explore the effect of structural complexity on the Perumytilus assemblage, we manipulated mussel size with experimental bags containing small and large individuals. Predators, grazers and mobile organisms were more abundant among smaller mussels, with smaller gap volume, whereas the barnacle Jehlius cirratus was more abundant on larger mussels. In conclusion, point-source nutrient addition to the mussel bed did not enhance primary production. However, the modification of structural characteristics related to mussel size induced changes in the faunal assemblage. Thus, it seems that in this nutrient-rich system, nutrient enhancement would not significantly affect Perumytilus and its assemblage, whereas structural habitat seems to play an important role in shaping this community.

  16. Space Use and Habitat Selection by Resident and Transient Coyotes (Canis latrans.

    Directory of Open Access Journals (Sweden)

    Joseph W Hinton

    Full Text Available Little information exists on coyote (Canis latrans space use and habitat selection in the southeastern United States and most studies conducted in the Southeast have been carried out within small study areas (e.g., ≤1,000 km2. Therefore, studying the placement, size, and habitat composition of coyote home ranges over broad geographic areas could provide relevant insights regarding how coyote populations adjust to regionally varying ecological conditions. Despite an increasing number of studies of coyote ecology, few studies have assessed the role of transiency as a life-history strategy among coyotes. During 2009-2011, we used GPS radio-telemetry to study coyote space use and habitat selection on the Albemarle Peninsula of northeastern North Carolina. We quantified space use and 2nd- and 3rd-order habitat selection for resident and transient coyotes to describe space use patterns in a predominantly agricultural landscape. The upper limit of coyote home-range size was approximately 47 km2 and coyotes exhibiting shifting patterns of space use of areas >65 km2 were transients. Transients exhibited localized space use patterns for short durations prior to establishing home ranges, which we defined as "biding" areas. Resident and transient coyotes demonstrated similar habitat selection, notably selection of agricultural over forested habitats. However, transients exhibited stronger selection for roads than resident coyotes. Although transient coyotes are less likely to contribute reproductively to their population, transiency may be an important life history trait that facilitates metapopulation dynamics through dispersal and the eventual replacement of breeding residents lost to mortality.

  17. Habitat Selection by Marico Flycatchers and Chat Flycatchers in the Kalahari Gemsbok National Park

    Directory of Open Access Journals (Sweden)

    S.K. Frost

    1987-10-01

    Full Text Available Habitat selection by Marico Flycatchers and Chat Flycatchers in the Kalahari Gemsbok National Park was studied during September 1985. Marico Flycatchers were found mainly along the rivers and in dune areas vegetated with tree savanna, and in both these habitats were predominantly associated with tall trees. Chat Flycatchers were found mainly in dunes vegetated with low shrubs and along areas of open river terrace. There was little difference in the overall height of the perches selected by the two species, and on the single occasion that they were seen foraging close together neither showed aggression towards the other.

  18. Habitat selection of endemic birds in temperate forests in a biodiversity "Hotspot"

    Directory of Open Access Journals (Sweden)

    Roberto A. Moreno-García

    2014-08-01

    Full Text Available Aim of study: Our objective was to find habitat associations at a microhabitat level for two endemic birds in a Chilean temperate forest (biodiversity “hotspots”, in order to integrate biodiversity into forest planning.Area of study: Nahuelbuta Range, Chile.Material and methods: The two birds studied were Scelorchilus rubecula (Chucao Tapaculo and Scytalopus magellanicus (Magellanic Tapaculo, both belonging to the Rhinocryptidae family. Presence or absence of the two species was sampled in 57 census spots. Habitat was categorized according to presence/absence results. We assessed the influence of abiotic variables (altitude, exposure, slope and vegetation structure (percentage of understory cover, number of strata using a statistical cluster analysis.Main results: The two bird species selected the habitat. Most frequent presence was detected at a range of 600-1100 masl, but Magellanic Tapaculo was associated to more protected sites in terms of vegetation structure (50-75% for understory cover and 2-3 strata. Slope was the most relevant abiotic variable in habitat selection due to its linkage to vegetation traits in this area.Research highlights: Our results can help managers to integrate biodiversity (endemic fauna species into forest planning by preserving certain traits of the vegetation as part of a habitat (at a microhabitat level selected by the fauna species. That planning should be implemented with both an adequate wood harvesting cuts system and specific silvicultural treatments.Key words: Chile; Nahuelbuta; rhinocryptidae; cluster analysis; rorest planning; vegetation structure.

  19. Habitat Selectivity and Reliance on Live Corals for Indo-Pacific Hawkfishes (Family: Cirrhitidae)

    KAUST Repository

    Coker, Darren James

    2015-11-03

    Hawkfishes (family: Cirrhitidae) are small conspicuous reef predators that commonly perch on, or shelter within, the branches of coral colonies. This study examined habitat associations of hawkfishes, and explicitly tested whether hawkfishes associate with specific types of live coral. Live coral use and habitat selectivity of hawkfishes was explored at six locations from Chagos in the central Indian Ocean extending east to Fiji in the Pacific Ocean. A total of 529 hawkfishes from seven species were recorded across all locations with 63% of individuals observed perching on, or sheltering within, live coral colonies. Five species (all except Cirrhitus pinnulatus and Cirrhitichthys oxycephalus) associated with live coral habitats. Cirrhitichthys falco selected for species of Pocillopora while Paracirrhites arcatus and P. forsteri selected for both Pocillopora and Acropora, revealing that these habitats are used disproportionately more than expected based on the local cover of these coral genera. Habitat selection was consistent across geographic locations, and species of Pocillopora were the most frequently used and most consistently selected even though this coral genus never comprised more than 6% of the total coral cover at any of the locations. Across locations, Paracirrhites arcatus and P. forsteri were the most abundant species and variation in their abundance corresponded with local patterns of live coral cover and abundance of Pocilloporid corals, respectively. These findings demonstrate the link between small predatory fishes and live coral habitats adding to the growing body of literature highlighting that live corals (especially erect branching corals) are critically important for sustaining high abundance and diversity of fishes on coral reefs.

  20. Reproductive habitat selection in alien and native populations of the genus Discoglossus

    Science.gov (United States)

    Escoriza, Daniel; Boix, Dani

    2014-08-01

    The existence of suitable breeding habitats is an important factor explaining the regional presence of an anuran species. This study examined patterns of habitat selection in populations of three species of the genus Discoglossus: Discoglossusgalganoi (south-western Iberian Peninsula), Discoglossusscovazzi (Morocco) and Discoglossuspictus (three different areas were included in the study: Sicily, Tunisia and north-eastern Iberian Peninsula). The populations of D. pictus on the Iberian Peninsula are allochthonous, and analysis of these patterns may provide insights into the processes that regulate the invasion phase. The hypotheses tested were: (i) congeneric species show the same patterns of habitat selection, and alien species have been established following these patterns; (ii) there are differences in species associations between assemblages structured deterministically and by chance, i.e. native versus invaded assemblages. The larval habitats of three species of this genus were characterized by measuring physical and chemical parameters of the water bodies. We examined the covariation between the presence of Discoglossus species and the species richness of sympatric anurans, and investigated a possible relationship between morphological similarity (as a proxy of functional group) and overlap in habitat use. The results showed that congeneric species are morphologically conservative and also select very similar types of aquatic habitat. The alien population and other sympatric species showed a high degree of overlap in habitat use, which was greater than that observed in the native assemblage with a similar functional richness. Species associations were not structured on the basis of morphological similarity in any of the assemblages. Among native populations, the presence of Discoglossus was either negatively correlated or not significantly correlated with species richness. Only the alien population showed a positive correlation between its presence and species

  1. An appraisal of the fitness consequences of forest disturbance for wildlife using habitat selection theory.

    Science.gov (United States)

    Hodson, James; Fortin, Daniel; Leblanc, Mélanie-Louise; Bélanger, Louis

    2010-09-01

    Isodar theory can help to unveil the fitness consequences of habitat disturbance for wildlife through an evaluation of adaptive habitat selection using patterns of animal abundance in adjacent habitats. By incorporating measures of disturbance intensity or variations in resource availability into fitness-density functions, we can evaluate the functional form of isodars expected under different disturbance-fitness relationships. Using this framework, we investigated how a gradient of forest harvesting disturbance and differences in resource availability influenced habitat quality for snowshoe hares (Lepus americanus) and red-backed voles (Myodes gapperi) using pairs of logged and uncut boreal forest. Isodars for both species had positive intercepts, indicating reductions to maximum potential fitness in logged stands. Habitat selection by hares depended on both conspecific density and differences in canopy cover between harvested and uncut stands. Fitness-density curves for hares in logged stands were predicted to shift from diverging to converging with those in uncut forest across a gradient of high to low disturbance intensity. Selection for uncut forests thus became less pronounced with increasing population size at low levels of logging disturbance. Voles responded to differences in moss cover between habitats which reflected moisture availability. Lower moss cover in harvested stands either reduced maximum potential fitness or increased the relative rate of decline in fitness with density. Differences in vole densities between harvested and uncut stands were predicted, however, to diminish as populations increased. Our findings underscore the importance of accounting for density-dependent behaviors when evaluating how changing habitat conditions influence animal distribution.

  2. An appraisal of the fitness consequences of forest disturbance for wildlife using habitat selection theory.

    Science.gov (United States)

    Hodson, James; Fortin, Daniel; Leblanc, Mélanie-Louise; Bélanger, Louis

    2010-09-01

    Isodar theory can help to unveil the fitness consequences of habitat disturbance for wildlife through an evaluation of adaptive habitat selection using patterns of animal abundance in adjacent habitats. By incorporating measures of disturbance intensity or variations in resource availability into fitness-density functions, we can evaluate the functional form of isodars expected under different disturbance-fitness relationships. Using this framework, we investigated how a gradient of forest harvesting disturbance and differences in resource availability influenced habitat quality for snowshoe hares (Lepus americanus) and red-backed voles (Myodes gapperi) using pairs of logged and uncut boreal forest. Isodars for both species had positive intercepts, indicating reductions to maximum potential fitness in logged stands. Habitat selection by hares depended on both conspecific density and differences in canopy cover between harvested and uncut stands. Fitness-density curves for hares in logged stands were predicted to shift from diverging to converging with those in uncut forest across a gradient of high to low disturbance intensity. Selection for uncut forests thus became less pronounced with increasing population size at low levels of logging disturbance. Voles responded to differences in moss cover between habitats which reflected moisture availability. Lower moss cover in harvested stands either reduced maximum potential fitness or increased the relative rate of decline in fitness with density. Differences in vole densities between harvested and uncut stands were predicted, however, to diminish as populations increased. Our findings underscore the importance of accounting for density-dependent behaviors when evaluating how changing habitat conditions influence animal distribution. PMID:20658153

  3. The effect of adult aggression on habitat selection by settlers of two coral-dwelling damselfishes.

    Directory of Open Access Journals (Sweden)

    Ofer Ben-Tzvi

    Full Text Available Coral-reef fishes experience a major challenge when facing settlement in a multi-threat environment, within which, using settlement cues, they need to select a suitable site. Studies in laboratories and artificial setups have shown that the presence of conspecific adults often serves as a positive settlement cue, whose value is explained by the increased survival of juveniles in an already proven fit environment. However, settlement in already inhabited corals may expose the recruits to adult aggression. Daily observations and manipulation experiments were used in the present study, which was conducted in the natural reef. We revealed differential strategies of settlers, which do not necessarily join conspecific adults. Dascyllus aruanus prefer to settle near (not with their aggressive adults, and to join them only after gaining in size; whereas Dascyllus marginatus settlers in densely populated reefs settle independently of their adult distribution. Our results present different solutions to the challenges faced by fish recruits while selecting their microhabitat, and emphasize the complexity of habitat selection by the naïve settlers. Although laboratory experiments are important to the understanding of fish habitat selection, further studies in natural habitats are essential in order to elucidate the actual patterns of settlement and habitat selection, which are crucial for the survival of coral-reef fish populations.

  4. Landscape-scale habitat selection by fishers translocated to the Olympic Peninsula of Washington

    Science.gov (United States)

    Lewis, Jeffrey C.; Jenkins, Kurt J.; Happe, Patricia J.; Manson, David J.; McCalmon, Marc

    2016-01-01

    The fisher was extirpated from much of the Pacific Northwestern United States during the mid- to late-1900s and is now proposed for federal listing as a threatened species in all or part of its west coast range. Following the translocation of 90 fishers from central British Columbia, Canada, to the Olympic Peninsula of Washington State from 2008 to 2010, we investigated the landscape-scale habitat selection of reintroduced fishers across a broad range of forest ages and disturbance histories, providing the first information on habitat relationships of newly reintroduced fishers in coastal coniferous forests in the Pacific Northwest. We developed 17 a priori models to evaluate several habitat-selection hypotheses based on premises of habitat models used to forecast habitat suitability for the reintroduced population. Further, we hypothesized that female fishers, because of their smaller body size than males, greater vulnerability to predation, and specific reproductive requirements, would be more selective than males for mid- to late-seral forest communities, where complex forest structural elements provide secure foraging, resting, and denning sites. We assessed 11 forest structure and landscape characteristics within the home range core-areas used by 19 females and 12 males and within randomly placed pseudo core areas that represented available habitats. We used case-controlled logistic regression to compare the characteristics of used and pseudo core areas and to assess selection by male and female fishers. Females were more selective of core area placement than males. Fifteen of 19 females (79%) and 5 of 12 males (42%) selected core areas within federal lands that encompassed primarily forests with an overstory of mid-sized or large trees. Male fishers exhibited only weak selection for core areas dominated by forests with an overstory of small trees, primarily on land managed for timber production or at high elevations. The amount of natural open area best

  5. Cleaner wrasse influence habitat selection of young damselfish

    Science.gov (United States)

    Sun, D.; Cheney, K. L.; Werminghausen, J.; McClure, E. C.; Meekan, M. G.; McCormick, M. I.; Cribb, T. H.; Grutter, A. S.

    2016-06-01

    The presence of bluestreak cleaner wrasse, Labroides dimidiatus, on coral reefs increases total abundance and biodiversity of reef fishes. The mechanism(s) that cause such shifts in population structure are unclear, but it is possible that young fish preferentially settle into microhabitats where cleaner wrasse are present. As a first step to investigate this possibility, we conducted aquarium experiments to examine whether settlement-stage and young juveniles of ambon damselfish, Pomacentrus amboinensis, selected a microhabitat near a cleaner wrasse (adult or juvenile). Both settlement-stage (0 d post-settlement) and juvenile (~5 weeks post-settlement) fish spent a greater proportion of time in a microhabitat adjacent to L. dimidiatus than in one next to a control fish (a non-cleaner wrasse, Halichoeres melanurus) or one where no fish was present. This suggests that cleaner wrasse may serve as a positive cue during microhabitat selection. We also conducted focal observations of cleaner wrasse and counts of nearby damselfishes (1 m radius) to examine whether newly settled fish obtained direct benefits, in the form of cleaning services, from being near a cleaner wrasse. Although abundant, newly settled recruits (reinforces the potentially important role of mutualism during the processes of settlement and recruitment of young reef fishes.

  6. Reef fishes can recognize bleached habitat during settlement: sea anemone bleaching alters anemonefish host selection.

    Science.gov (United States)

    Scott, Anna; Dixson, Danielle L

    2016-05-25

    Understanding how bleaching impacts the settlement of symbiotic habitat specialists and whether there is flexibility in settlement choices with regard to habitat quality is essential given our changing climate. We used five anemonefishes (Amphiprion clarkii, Amphiprion latezonatus, Amphiprion ocellaris, Amphiprion percula and Premnas biaculeatus) and three host sea anemones (Entacmaea quadricolor, Heteractis crispa and Heteractis magnifica) in paired-choice flume experiments to determine whether habitat naive juveniles have the olfactory capabilities to distinguish between unbleached and bleached hosts, and how this may affect settlement decisions. All anemonefishes were able to distinguish between bleached and unbleached hosts, and responded only to chemical cues from species-specific host anemones irrespective of health status, indicating a lack of flexibility in host use. While bleached hosts were selected as habitat, this occurred only when unbleached options were unavailable, with the exception of A. latezonatus, which showed strong preferences for H. crispa regardless of health. This study highlights the potential deleterious indirect impacts of declining habitat quality during larval settlement in habitat specialists, which could be important in the field, given that bleaching events are becoming increasingly common. PMID:27226472

  7. Cattle grazing in semiarid forestlands: Habitat selection during periods of drought.

    Science.gov (United States)

    Roever, C L; DelCurto, T; Rowland, M; Vavra, M; Wisdom, M

    2015-06-01

    Climate change models are predicting increased frequency and severity of droughts in arid and semiarid environments, and these areas are responsible for much of the world's livestock production. Because cattle (Bos Taurus) grazing can impact the abundance, distribution, and ecological function of native plant and animal communities, it is important to understand how cattle might respond to increasingly arid conditions. Here, we evaluate changes in habitat selection by cattle across an 8-yr period as a function of rainfall and other environmental covariates. Using resource selection functions, we evaluated habitat selection based on 2 behaviors, stationary and mobile. Models revealed similarity in cattle habitat selection across years, with only modest changes in selection as a function of precipitation, despite marked seasonal and interannual differences in rainfall. Cattle preferred gentle slopes, forest edges, wet meadows, and areas near water as well as areas far from water on plateaus. Cattle avoided areas at intermediate distances from water, typically associated with steep slopes. As conditions became drier during the late season, cattle did not switch selection patterns but instead contracted their selection around water. Cattle also selected similar habitats whether they were mobile or stationary, possibly making microsite decisions therein. This consistent pattern of selection across years could be particularly problematic for riparian communities as climates become drier; however, it may also simplify cattle management, as range managers can focus vegetation monitoring efforts on riparian areas. Due to the uncertainty surrounding future climatic conditions, it is imperative that both range and wildlife managers develop long-term plans to continue managing these multiuse landscapes in an ecologically sustainable manner based on expected patterns of livestock grazing. PMID:26115307

  8. Seasonal habitat use and selection by grizzly bears in Northern British Columbia

    Science.gov (United States)

    Milakovic, B.; Parker, K.L.; Gustine, D.D.; Lay, R.J.; Walker, A.B.D.; Gillingham, M.P.

    2012-01-01

    We defined patterns of habitat use and selection by female grizzly bears (Ursus arctos) in the Besa-Prophet watershed of northern British Columbia. We fitted 13 adult females with Geographic Positioning System (GPS) radio-collars and monitored them between 2001 and 2004. We examined patterns of habitat selection by grizzly bears relative to topographical attributes and 3 potential surrogates of food availability: land-cover class, vegetation biomass or quality (as measured by the Normalized Difference Vegetation Index), and selection value for prey species themselves (moose [Alces alces], elk [Cervus elaphus], woodland caribou [Rangifer tarandus], Stone's sheep [Ovis dalli stonei]). Although vegetation biomass and quality, and selection values for prey were important in seasonal selection by some individual bears, land-cover class, elevation, aspect, and vegetation diversity most influenced patterns of habitat selection across grizzly bears, which rely on availability of plant foods and encounters with ungulate prey. Grizzly bears as a group avoided conifer stands and areas of low vegetation diversity, and selected for burned land-cover classes and high vegetation diversity across seasons. They also selected mid elevations from what was available within seasonal ranges. Quantifying relative use of different attributes helped place selection patterns within the context of the landscape. Grizzly bears used higher elevations (1,595??31 m SE) in spring and lower elevations (1,436??27 m) in fall; the range of average elevations used among individuals was highest (500 m) during the summer. During all seasons, grizzly bears most frequented aspects with high solar gain. Use was distributed across 10 land-cover classes and depended on season. Management and conservation actions must maintain a diverse habitat matrix distributed across a large elevational gradient to ensure persistence of grizzly bears as levels of human access increase in the northern Rocky Mountains

  9. Selection of habitat by the jaguar, Panthera onca (Carnivora: Felidae, in the upper Paraná River, Brazil

    Directory of Open Access Journals (Sweden)

    Laury Cullen Junior

    2013-08-01

    Full Text Available We used data from VHF and GPS radio-tagged jaguars, Panthera onca (Linnaeus, 1758 to quantify jaguar habitat selection and how adult individuals in the Upper Paraná River region selected among the available habitat types. We followed the framework in which animals make decisions about resource use at hierarchical stages, namely selection of home range within a study area (second-order selection and selection of patches within a home range (third-order selection. We quantified habitat preferences at two orders of selection with respect to habitat types and to test the null hypothesis that habitat utilization by jaguars was random at both study sites. Using compositional analysis, we assessed habitat selection by jaguars at second- and third-orders of selection. Jaguars consistently preferred dense marshes and primary forests, and avoided human-dominated areas such as intensively managed open pastures. Although the avoidance of disturbed and developed habitat types by jaguars is not surprising, this is the first study to document it. If small protected areas, such as the ones already existing in the Upper Paraná region, are to sustain jaguar populations they, must include and protect as many primary forests and marshlands as possible, so that jaguars can disperse, hunt wild prey and take care of their cubs without being disturbed. What is urgently needed in these jaguar-protected areas is the creation of larger protected areas that can sustain jaguars in their favored habitat.

  10. Microhabitat selection by marine mesoconsumers in a thermally heterogeneous habitat: behavioral thermoregulation or avoiding predation risk?

    Directory of Open Access Journals (Sweden)

    Jeremy J Vaudo

    Full Text Available Habitat selection decisions by consumers has the potential to shape ecosystems. Understanding the factors that influence habitat selection is therefore critical to understanding ecosystem function. This is especially true of mesoconsumers because they provide the link between upper and lower tropic levels. We examined the factors influencing microhabitat selection of marine mesoconsumers - juvenile giant shovelnose rays (Glaucostegus typus, reticulate whiprays (Himantura uarnak, and pink whiprays (H. fai - in a coastal ecosystem with intact predator and prey populations and marked spatial and temporal thermal heterogeneity. Using a combination of belt transects and data on water temperature, tidal height, prey abundance, predator abundance and ray behavior, we found that giant shovelnose rays and reticulate whiprays were most often found resting in nearshore microhabitats, especially at low tidal heights during the warm season. Microhabitat selection did not match predictions derived from distributions of prey. Although at a course scale, ray distributions appeared to match predictions of behavioral thermoregulation theory, fine-scale examination revealed a mismatch. The selection of the shallow nearshore microhabitat at low tidal heights during periods of high predator abundance (warm season suggests that this microhabitat may serve as a refuge, although it may come with metabolic costs due to higher temperatures. The results of this study highlight the importance of predators in the habitat selection decisions of mesoconsumers and that within thermal gradients, factors, such as predation risk, must be considered in addition to behavioral thermoregulation to explain habitat selection decisions. Furthermore, increasing water temperatures predicted by climate change may result in complex trade-offs that might have important implications for ecosystem dynamics.

  11. Habitat selection of a large carnivore along human-wildlife boundaries in a highly modified landscape.

    Science.gov (United States)

    Takahata, Chihiro; Nielsen, Scott Eric; Takii, Akiko; Izumiyama, Shigeyuki

    2014-01-01

    When large carnivores occupy peripheral human lands conflict with humans becomes inevitable, and the reduction of human-carnivore interactions must be the first consideration for those concerned with conflict mitigation. Studies designed to identify areas of high human-bear interaction are crucial for prioritizing management actions. Due to a surge in conflicts, against a background of social intolerance to wildlife and the prevalent use of lethal control throughout Japan, Asiatic black bears (Ursus thibetanus) are now threatened by high rates of mortality. There is an urgent need to reduce the frequency of human-bear encounters if bear populations are to be conserved. To this end, we estimated the habitats that relate to human-bear interactions by sex and season using resource selection functions (RSF). Significant seasonal differences in selection for and avoidance of areas by bears were estimated by distance-effect models with interaction terms of land cover and sex. Human-bear boundaries were delineated on the basis of defined bear-habitat edges in order to identify areas that are in most need of proactive management strategies. Asiatic black bears selected habitats in close proximity to forest edges, forest roads, rivers, and red pine and riparian forests during the peak conflict season and this was correctly predicted in our human-bear boundary maps. Our findings demonstrated that bears selected abandoned forests and agricultural lands, indicating that it should be possible to reduce animal use near human lands by restoring season-specific habitat in relatively remote areas. Habitat-based conflict mitigation may therefore provide a practical means of creating adequate separation between humans and these large carnivores. PMID:24465947

  12. Habitat selection of a large carnivore along human-wildlife boundaries in a highly modified landscape.

    Directory of Open Access Journals (Sweden)

    Chihiro Takahata

    Full Text Available When large carnivores occupy peripheral human lands conflict with humans becomes inevitable, and the reduction of human-carnivore interactions must be the first consideration for those concerned with conflict mitigation. Studies designed to identify areas of high human-bear interaction are crucial for prioritizing management actions. Due to a surge in conflicts, against a background of social intolerance to wildlife and the prevalent use of lethal control throughout Japan, Asiatic black bears (Ursus thibetanus are now threatened by high rates of mortality. There is an urgent need to reduce the frequency of human-bear encounters if bear populations are to be conserved. To this end, we estimated the habitats that relate to human-bear interactions by sex and season using resource selection functions (RSF. Significant seasonal differences in selection for and avoidance of areas by bears were estimated by distance-effect models with interaction terms of land cover and sex. Human-bear boundaries were delineated on the basis of defined bear-habitat edges in order to identify areas that are in most need of proactive management strategies. Asiatic black bears selected habitats in close proximity to forest edges, forest roads, rivers, and red pine and riparian forests during the peak conflict season and this was correctly predicted in our human-bear boundary maps. Our findings demonstrated that bears selected abandoned forests and agricultural lands, indicating that it should be possible to reduce animal use near human lands by restoring season-specific habitat in relatively remote areas. Habitat-based conflict mitigation may therefore provide a practical means of creating adequate separation between humans and these large carnivores.

  13. Contrasting habitat selection amongst cephalopods in the Mediterranean Sea: When the environment makes the difference.

    Science.gov (United States)

    Lauria, V; Garofalo, G; Gristina, M; Fiorentino, F

    2016-08-01

    Conservation of fish habitat requires a deeper knowledge of how species distribution patterns are related to environmental factors. Habitat suitability modelling is an essential tool to quantify species' realised niches and understand species-environment relationships. Cephalopods are important players in the marine food web and a significant resource for fisheries; they are also very sensitive to environmental changes. Here a time series of fishery-independent data (1998-2011) was used to construct habitat suitability models and investigate the influence of environmental variables on four commercial cephalopods: Todaropsis eblanae, Illex coindetii, Eledone moschata and Eledone cirrhosa, in the central Mediterranean Sea. The main environmental predictors of cephalopod habitat suitability were depth, seafloor morphology, chlorophyll-a concentration, sea surface temperature and surface salinity. Predictive maps highlighted contrasting habitat selection amongst species. This study identifies areas where the important commercial species of cephalopods are concentrated and provides significant information for a future spatial based approach to fisheries management in the Mediterranean Sea. PMID:27371813

  14. Model-Based Selection of Areas for the Restoration of Acrocephalus paludicola Habitats in NE Germany

    Science.gov (United States)

    Frick, Annett; Tanneberger, Franziska; Bellebaum, Jochen

    2014-04-01

    The global Aquatic Warbler ( Acrocephalus paludicola, Vieillot, 1817) population has suffered a major decline due to the large-scale destruction of its natural habitat (fen mires). The species is at risk of extinction, especially in NE Germany/NW Poland. In this study, we developed habitat suitability models based on satellite and environmental data to identify potential areas for habitat restoration on which further surveys and planning should be focused. To create a reliable model, we used all Aquatic Warbler presences in the study area since 1990 as well as additional potentially suitable habitats identified in the field. We combined the presence/absence regression tree algorithm Cubist with the presence-only algorithm Maxent since both commonly outperform other algorithms. To integrate the separate model results, we present a new way to create a metamodel using the initial model results as variables. Additionally, a histogram approach was applied to further reduce the final search area to the most promising sites. Accuracy increased when using both remote sensing and environmental data. It was highest for the integrated metamodel (Cohen's Kappa of 0.4, P < 0.001). The final result of this study supports the selection of the most promising sites for Aquatic Warbler habitat restoration.

  15. Linking Dynamic Habitat Selection with Wading Bird Foraging Distributions across Resource Gradients.

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    James M Beerens

    Full Text Available Species distribution models (SDM link species occurrence with a suite of environmental predictors and provide an estimate of habitat quality when the variable set captures the biological requirements of the species. SDMs are inherently more complex when they include components of a species' ecology such as conspecific attraction and behavioral flexibility to exploit resources that vary across time and space. Wading birds are highly mobile, demonstrate flexible habitat selection, and respond quickly to changes in habitat quality; thus serving as important indicator species for wetland systems. We developed a spatio-temporal, multi-SDM framework using Great Egret (Ardea alba, White Ibis (Eudocimus albus, and Wood Stork (Mycteria Americana distributions over a decadal gradient of environmental conditions to predict species-specific abundance across space and locations used on the landscape over time. In models of temporal dynamics, species demonstrated conditional preferences for resources based on resource levels linked to differing temporal scales. Wading bird abundance was highest when prey production from optimal periods of inundation was concentrated in shallow depths. Similar responses were observed in models predicting locations used over time, accounting for spatial autocorrelation. Species clustered in response to differing habitat conditions, indicating that social attraction can co-vary with foraging strategy, water-level changes, and habitat quality. This modeling framework can be applied to evaluate the multi-annual resource pulses occurring in real-time, climate change scenarios, or restorative hydrological regimes by tracking changing seasonal and annual distribution and abundance of high quality foraging patches.

  16. Raccoon spatial requirements and multi-scale habitat selection within an intensively managed central Appalachian forest

    Science.gov (United States)

    Owen, Sheldon F.; Berl, Jacob L.; Edwards, John W.; Ford, W. Mark; Wood, Petra Bohall

    2015-01-01

    We studied a raccoon (Procyon lotor) population within a managed central Appalachian hardwood forest in West Virginia to investigate the effects of intensive forest management on raccoon spatial requirements and habitat selection. Raccoon home-range (95% utilization distribution) and core-area (50% utilization distribution) size differed between sexes with males maintaining larger (2×) home ranges and core areas than females. Home-range and core-area size did not differ between seasons for either sex. We used compositional analysis to quantify raccoon selection of six different habitat types at multiple spatial scales. Raccoons selected riparian corridors (riparian management zones [RMZ]) and intact forests (> 70 y old) at the core-area spatial scale. RMZs likely were used by raccoons because they provided abundant denning resources (i.e., large-diameter trees) as well as access to water. Habitat composition associated with raccoon foraging locations indicated selection for intact forests, riparian areas, and regenerating harvest (stands managed forests in the central Appalachians.

  17. Selection and durability of seal materials for a bedded salt repository: preliminary studies

    International Nuclear Information System (INIS)

    This report details preliminary results of both experimental and theoretical studies of cementitious seal materials for use in a proposed nuclear waste repository in bedded salt. Effects of changes in bulk composition and environment upon phase stability and physical/mechanical properties have been evaluated for more than 25 formulations. Bonding and interfacial characteristics of the region between host rock and seal material or concrete aggregate and cementitious matrix for selected formulations have been studied. Compatibilities of clays and zeolites in brines typical of the SE New Mexico region have been investigated, and their stabilities reviewed. Results of these studies have led to the conclusion that cementitious materials can be formulated which are compatible with the major rock types in a bedded salt repository environment. Strengths are more than adequate, permeabilities are consistently very low, and elastic moduli generally increase only very slightly with time. Seal formulation guidelines and recommendations for present and future work are presented. 73 references, 25 figures, 61 tables

  18. Selection and durability of seal materials for a bedded salt repository: preliminary studies

    Energy Technology Data Exchange (ETDEWEB)

    Roy, D.M.; Grutzeck, M.W.; Wakeley, L.D.

    1983-11-01

    This report details preliminary results of both experimental and theoretical studies of cementitious seal materials for use in a proposed nuclear waste repository in bedded salt. Effects of changes in bulk composition and environment upon phase stability and physical/mechanical properties have been evaluated for more than 25 formulations. Bonding and interfacial characteristics of the region between host rock and seal material or concrete aggregate and cementitious matrix for selected formulations have been studied. Compatibilities of clays and zeolites in brines typical of the SE New Mexico region have been investigated, and their stabilities reviewed. Results of these studies have led to the conclusion that cementitious materials can be formulated which are compatible with the major rock types in a bedded salt repository environment. Strengths are more than adequate, permeabilities are consistently very low, and elastic moduli generally increase only very slightly with time. Seal formulation guidelines and recommendations for present and future work are presented. 73 references, 25 figures, 61 tables.

  19. Habitat selection by a focal predator (Canis lupus) in a multiprey ecosystem of the northern Rockies

    Science.gov (United States)

    Milakovic, B.; Parker, K.L.; Gustine, D.D.; Lay, R.J.; Walker, A.B.D.; Gillingham, M.P.

    2011-01-01

    Large predators respond to land cover and physiography that maximize the likelihood of encountering prey. Using locations from global positioning system-collared wolves (Canis lupus), we examined whether land cover, vegetation productivity or change, or habitat-selection value for ungulate prey species themselves most influenced patterns of selection by wolves in a large, intact multiprey system of northern British Columbia. Selection models based on land cover, in combination with topographical features, consistently outperformed models based on indexes of vegetation quantity and quality (using normalized difference vegetation index) or on selection value to prey species (moose [Alces americanus], elk [Cervus elaphus], woodland caribou [Rangifer tarandus], and Stone's sheep [Ovis dalli stonei]). Wolves generally selected for shrub communities and high diversity of cover across seasons and avoided conifer stands and non-vegetated areas and west aspects year-round. Seasonal selection strategies were not always reflected in use patterns, which showed highest frequency of use in riparian, shrub, and conifer classes. Patterns of use and selection for individual wolf packs did not always conform to global models, and appeared related to the distribution of land cover and terrain within respective home ranges. Our findings corroborate the biological linkages between wolves and their habitat related to ease of movement and potential prey associations. ?? American 2011 Society of Mammalogists.

  20. Habitat selection in a reintroduced population: social effects differ between natal and post-release dispersal

    OpenAIRE

    Richardson, K. M.; Ewen, J. G.

    2011-01-01

    Animal translocations are human-induced colonizations that can represent opportunities to contribute to the knowledge on the behavioral and demographic processes involved in the establishment of animal populations. Habitat selection behaviors, such as social cueing, have strong implications on dispersal and affect the establishment success of translocations. Using modeling simulations with a two-population network model (a translocated population and a remnant population), we investigated the...

  1. Identification of landscape features influencing gene flow: How useful are habitat selection models?

    Science.gov (United States)

    Roffler, Gretchen H; Schwartz, Michael K; Pilgrim, Kristy L; Talbot, Sandra L; Sage, George K; Adams, Layne G; Luikart, Gordon

    2016-07-01

    Understanding how dispersal patterns are influenced by landscape heterogeneity is critical for modeling species connectivity. Resource selection function (RSF) models are increasingly used in landscape genetics approaches. However, because the ecological factors that drive habitat selection may be different from those influencing dispersal and gene flow, it is important to consider explicit assumptions and spatial scales of measurement. We calculated pairwise genetic distance among 301 Dall's sheep (Ovis dalli dalli) in southcentral Alaska using an intensive noninvasive sampling effort and 15 microsatellite loci. We used multiple regression of distance matrices to assess the correlation of pairwise genetic distance and landscape resistance derived from an RSF, and combinations of landscape features hypothesized to influence dispersal. Dall's sheep gene flow was positively correlated with steep slopes, moderate peak normalized difference vegetation indices (NDVI), and open land cover. Whereas RSF covariates were significant in predicting genetic distance, the RSF model itself was not significantly correlated with Dall's sheep gene flow, suggesting that certain habitat features important during summer (rugged terrain, mid-range elevation) were not influential to effective dispersal. This work underscores that consideration of both habitat selection and landscape genetics models may be useful in developing management strategies to both meet the immediate survival of a species and allow for long-term genetic connectivity.

  2. Identification of landscape features influencing gene flow: How useful are habitat selection models?

    Science.gov (United States)

    Roffler, Gretchen H.; Schwartz, Michael K.; Pilgrim, Kristy L.; Talbot, Sandra; Sage, Kevin; Adams, Layne G.; Luikart, Gordon

    2016-01-01

    Understanding how dispersal patterns are influenced by landscape heterogeneity is critical for modeling species connectivity. Resource selection function (RSF) models are increasingly used in landscape genetics approaches. However, because the ecological factors that drive habitat selection may be different from those influencing dispersal and gene flow, it is important to consider explicit assumptions and spatial scales of measurement. We calculated pairwise genetic distance among 301 Dall's sheep (Ovis dalli dalli) in southcentral Alaska using an intensive noninvasive sampling effort and 15 microsatellite loci. We used multiple regression of distance matrices to assess the correlation of pairwise genetic distance and landscape resistance derived from an RSF, and combinations of landscape features hypothesized to influence dispersal. Dall's sheep gene flow was positively correlated with steep slopes, moderate peak normalized difference vegetation indices (NDVI), and open land cover. Whereas RSF covariates were significant in predicting genetic distance, the RSF model itself was not significantly correlated with Dall's sheep gene flow, suggesting that certain habitat features important during summer (rugged terrain, mid-range elevation) were not influential to effective dispersal. This work underscores that consideration of both habitat selection and landscape genetics models may be useful in developing management strategies to both meet the immediate survival of a species and allow for long-term genetic connectivity.

  3. Preliminary performance analysis of a transverse flow spectrally selective two-slab packed bed volumetric receiver

    Science.gov (United States)

    Roos, Thomas H.; Harms, Thomas M.

    2016-05-01

    A new volumetric receiver concept has been investigated, based on an adaptation of the spectrally selective, two-slab packed bed volumetric receiver concept of Flamant et al. Both slabs comprise spheres of identical size - borosilicate for the transparent slab 1 and SiC for the opaque slab 2 - which are ordered in a hexagonally close-packed bed. The flow direction has been changed from parallel to the incident radiation and perpendicular to the window, to parallel to the window and perpendicular to the incident radiation (transverse flow). The gap between the window and slab 1 has been removed, so the bed is held in place by the sidewalls, the floor and the window, allowing arbitrary orientation and dispensing with the need for beam-down operation. The receiver has been subjected to constant solar radiative load of approximately 70 suns, and the effect of variations in flowrate, the degree of air preheating as well as the thickness of slab 2 on the outlet air temperature distributions have been measured. The effect of reducing the flowrate for both slab 2 thicknesses is to increase temperature everywhere relative to the maximum temperature, having the effect of "flattening" the pattern factor and tending towards more uniform temperature distribution. The effect of preheating for both slab 2 thicknesses is to move the location of maximum temperature deeper into the bed (away from the window). No significant effect is observed on pattern factor in the transparent region of the bed (slab 1), but temperatures in the opaque region increase relative to the maximum temperature. The results are consistent with the increasing contribution of radiative heat transfer relative to convective and conductive heat transfer as the bed temperature rises. In all cases, the air temperature closest to the window is lower than the maximum temperature, demonstrating the volumetric heating effect. Increasing the outlet air temperature (either due to preheating or due to decreasing

  4. Habitat selection and reproductive success of Lewis's Woodpecker (Melanerpes lewis at its northern limit.

    Directory of Open Access Journals (Sweden)

    Xiang Zhu

    Full Text Available Lewis's Woodpecker (Melanerpes lewis has experienced population declines in both Canada and the United States and in 2010 was assigned a national listing of threatened in Canada. We conducted a two-year study (2004-2005 of this species at its northern range limit, the South Okanagan Valley in British Columbia, Canada. Our main objective was to determine whether the habitat features that influenced nest-site selection also predicted nest success, or whether other factors (e.g. cavity dimensions, clutch initiation date or time of season were more important. Nest tree decay class, density of suitable cavities and total basal area of large trees were the best predictors of nest-site selection, but these factors were unrelated to nesting success. Estimates of demographic parameters (mean ± SE included daily nest survival rate (0.988±0.003, years combined, nest success (0.52±0.08, clutch size (5.00±0.14 eggs, female fledglings per successful nest (1.31±0.11, and annual productivity (0.68±0.12 female fledglings per nest per year. Although higher nest survival was associated with both early and late initiated clutches, early-initiated clutches allowed birds to gain the highest annual productivity as early clutches were larger. Nests in deep cavities with small entrances experienced lower predation risk especially during the peak period of nest predation. We concluded that nest-site selection can be predicted by a number of easily measured habitat variables, whereas nest success depended on complicated ecological interactions among nest predators, breeding behaviors, and cavity features. Thus, habitat-based conservation strategies should also consider ecological factors that may not be well predicted by habitat.

  5. Habitat selection by Eld's deer following relocation to a patchy landscape.

    Science.gov (United States)

    Pan, Duo; Song, Yan-Ling; Zeng, Zhi-Gao; Bravery, Benjamin D

    2014-01-01

    An emerging issue in wildlife conservation is the re-establishment of viable populations of endangered species in suitable habitats. Here, we studied habitat selection by a population of Hainan Eld's deer (Cervus eldi) relocated to a patchy landscape of farmland and forest. Hainan Eld's deer were pushed to the brink of extinction in the 1970s, but their population expanded rapidly from 26 to more than 1000 individuals by 2003 through effective reserve protection. As part of a wider relocation and population management strategy, 131 deer were removed from the reserve and reintroduced into a farmland-forest landscape in 2005. Habitat use under a context of human disturbance was surveyed by monitoring 19 radio-collared animals. The majority of deer locations (77%) were within 0.6-2 km of villages. Annual home ranges of these collared deer averaged 725 ha (SD 436), which was 55% of the size of the reserve from which they had originated. The annual home ranges contained 54% shrub-grassland, 26% forest and 15% farmland. The relocated deer population selected landscape comprising slash-and-burn agriculture and forest, and avoided both intensively farmed areas and areas containing only forest. Within the selected landscape, deer preferred swiddens and shrub-grasslands. Forests above 300 m in elevation were avoided, whereas forests below 300 m in elevation were overrepresented during the dry season and randomly used during the wet season. Our findings show that reintroduced deer can utilize disturbed habitats, and further demonstrate that subsistence agroforest ecosystems have the capacity to sustain endangered ungulates. PMID:24614039

  6. Habitat Selection by Eld’s Deer following Relocation to a Patchy Landscape

    Science.gov (United States)

    Pan, Duo; Song, Yan-Ling; Zeng, Zhi-Gao; Bravery, Benjamin D.

    2014-01-01

    An emerging issue in wildlife conservation is the re-establishment of viable populations of endangered species in suitable habitats. Here, we studied habitat selection by a population of Hainan Eld’s deer (Cervus eldi) relocated to a patchy landscape of farmland and forest. Hainan Eld’s deer were pushed to the brink of extinction in the 1970s, but their population expanded rapidly from 26 to more than 1000 individuals by 2003 through effective reserve protection. As part of a wider relocation and population management strategy, 131 deer were removed from the reserve and reintroduced into a farmland-forest landscape in 2005. Habitat use under a context of human disturbance was surveyed by monitoring 19 radio-collared animals. The majority of deer locations (77%) were within 0.6–2 km of villages. Annual home ranges of these collared deer averaged 725 ha (SD 436), which was 55% of the size of the reserve from which they had originated. The annual home ranges contained 54% shrub-grassland, 26% forest and 15% farmland. The relocated deer population selected landscape comprising slash-and-burn agriculture and forest, and avoided both intensively farmed areas and areas containing only forest. Within the selected landscape, deer preferred swiddens and shrub-grasslands. Forests above 300 m in elevation were avoided, whereas forests below 300 m in elevation were overrepresented during the dry season and randomly used during the wet season. Our findings show that reintroduced deer can utilize disturbed habitats, and further demonstrate that subsistence agroforest ecosystems have the capacity to sustain endangered ungulates. PMID:24614039

  7. Habitat selection by Eld's deer following relocation to a patchy landscape.

    Directory of Open Access Journals (Sweden)

    Duo Pan

    Full Text Available An emerging issue in wildlife conservation is the re-establishment of viable populations of endangered species in suitable habitats. Here, we studied habitat selection by a population of Hainan Eld's deer (Cervus eldi relocated to a patchy landscape of farmland and forest. Hainan Eld's deer were pushed to the brink of extinction in the 1970s, but their population expanded rapidly from 26 to more than 1000 individuals by 2003 through effective reserve protection. As part of a wider relocation and population management strategy, 131 deer were removed from the reserve and reintroduced into a farmland-forest landscape in 2005. Habitat use under a context of human disturbance was surveyed by monitoring 19 radio-collared animals. The majority of deer locations (77% were within 0.6-2 km of villages. Annual home ranges of these collared deer averaged 725 ha (SD 436, which was 55% of the size of the reserve from which they had originated. The annual home ranges contained 54% shrub-grassland, 26% forest and 15% farmland. The relocated deer population selected landscape comprising slash-and-burn agriculture and forest, and avoided both intensively farmed areas and areas containing only forest. Within the selected landscape, deer preferred swiddens and shrub-grasslands. Forests above 300 m in elevation were avoided, whereas forests below 300 m in elevation were overrepresented during the dry season and randomly used during the wet season. Our findings show that reintroduced deer can utilize disturbed habitats, and further demonstrate that subsistence agroforest ecosystems have the capacity to sustain endangered ungulates.

  8. Magnetically stabilized bed reactor for selective hydrogenation of olefins in reformate with amorphous nickel alloy catalyst

    Institute of Scientific and Technical Information of China (English)

    Xuhong; Mu; Enze; Min

    2007-01-01

    A magnetically stabilized bed (MSB) reactor for selective hydrogenation of olefins in reformate was developed by combining the advantages of MSB and amorphous nickel alloy catalyst. The effects of operating conditions, such as temperature, pressure, liquid space velocity, hydrogen-to-oil ratio, and magnetic field intensity on the reaction were studied. A mathematical model of MSB reactor for hydrogenation of olefins in reformate was established. A reforming flow scheme with a post-hydrogenation MSB reactor was proposed. Finally, MSB hydrogenation was compared with clay treatment and conventional post-hydrogenation.

  9. Breeding habitat selection by houbara bustard (Chlamydotis[undulata] macqueenii) in Mori, Xinjiang, China

    Institute of Scientific and Technical Information of China (English)

    YANG Weikang(杨维康); QIAO Jianfang(乔建芳); Olivier Combreau; YAO Jun(姚军); GAO Xingyi(高行宜); ZHONG Wenqin(钟文勤)

    2002-01-01

    The breeding habitat selection by houbara bustards in Mori, Xinjiang, China duringthe breeding seasons from April to June 1998-2000 was studied. Most of habitats chosen forbreeding were short sub-shrubby and open areas close to high bushy patches. The nesting re-males clearly prefer Iow covered areas and avoid densely covered and high vegetation sites. Thenumber of herb species was significantly smaller at nest sites than at randomly selected sites.Only the distance to the closest fox den contributed the most to discrimination between successfuland predated nests. The average distance to the closest fox den was significantly longer at suc-cessful nests than at depredated nests. Vegetative density, plant species richness, topography anddistance to the closest fox den are possibly the most important factors that determined the nestsites selection of houbara bustard. The displaying males clearly prefer Iow covered areas andavoid densely covered and high vegetation sites. The vegetation density and number of plant spe-cies at display sites was significantly lower than that at randomly selected sites. The average dis-tance to the closest bushy patch was significantly shorter at display sites than at random sites.Plant species richness, vegetative density, vegetative cover and distance to the bushy patches arepossibly the most important factors for the display sites selection of houbara bustard.

  10. The influence of mitigation on sage-grouse habitat selection within an energy development field.

    Directory of Open Access Journals (Sweden)

    Bradley C Fedy

    Full Text Available Growing global energy demands ensure the continued growth of energy development. Energy development in wildlife areas can significantly impact wildlife populations. Efforts to mitigate development impacts to wildlife are on-going, but the effectiveness of such efforts is seldom monitored or assessed. Greater sage-grouse (Centrocercus urophasianus are sensitive to energy development and likely serve as an effective umbrella species for other sagebrush-steppe obligate wildlife. We assessed the response of birds within an energy development area before and after the implementation of mitigation action. Additionally, we quantified changes in habitat distribution and abundance in pre- and post-mitigation landscapes. Sage-grouse avoidance of energy development at large spatial scales is well documented. We limited our research to directly within an energy development field in order to assess the influence of mitigation in close proximity to energy infrastructure. We used nest-location data (n = 488 within an energy development field to develop habitat selection models using logistic regression on data from 4 years of research prior to mitigation and for 4 years following the implementation of extensive mitigation efforts (e.g., decreased activity, buried powerlines. The post-mitigation habitat selection models indicated less avoidance of wells (well density β = 0.18 ± 0.08 than the pre-mitigation models (well density β = -0.09 ± 0.11. However, birds still avoided areas of high well density and nests were not found in areas with greater than 4 wells per km2 and the majority of nests (63% were located in areas with ≤ 1 well per km2. Several other model coefficients differed between the two time periods and indicated stronger selection for sagebrush (pre-mitigation β = 0.30 ± 0.09; post-mitigation β = 0.82 ± 0.08 and less avoidance of rugged terrain (pre-mitigation β = -0.35 ± 0.12; post-mitigation β = -0.05 ± 0.09. Mitigation efforts

  11. Glacial Refugia and Future Habitat Coverage of Selected Dactylorhiza Representatives (Orchidaceae.

    Directory of Open Access Journals (Sweden)

    Aleksandra M Naczk

    Full Text Available The intensively discussed taxonomic complexity of the Dactylorhiza genus is probably correlated with its migration history during glaciations and interglacial periods. Previous studies on past processes affecting the current distribution of Dactylorhiza species as well as the history of the polyploid complex formation were based only on molecular data. In the present study the ecological niche modeling (ENM technique was applied in order to describe the distribution of potential refugia for the selected Dactylorhiza representatives during the Last Glacial Maximum. Additionally, future changes in their potential habitat coverage were measured with regard to three various climatic change scenarios. The maximum entropy method was used to create models of suitable niche distribution. A database of Dactylorhiza localities was prepared on the grounds of information collected from literature and data gathered during field works. Our research indicated that the habitats of majority of the studied taxa will decrease by 2080, except for D. incarnata var. incarnata, for which suitable habitats will increase almost two-fold in the global scale. Moreover, the potential habitats of some taxa are located outside their currently known geographical ranges, e.g. the Aleutian Islands, the western slopes of the Rocky Mountains, Newfoundland, southern Greenland and Iceland. ENM analysis did not confirm that the Balkans, central Europe or central Russia served as the most important refugia for individual representatives of the Dactylorhiza incarnata/maculata complex. Our study rather indicated that the Black Sea coast, southern Apennines and Corsica were the main areas characterized by habitats suitable for most of the taxa.

  12. Glacial Refugia and Future Habitat Coverage of Selected Dactylorhiza Representatives (Orchidaceae).

    Science.gov (United States)

    Naczk, Aleksandra M; Kolanowska, Marta

    2015-01-01

    The intensively discussed taxonomic complexity of the Dactylorhiza genus is probably correlated with its migration history during glaciations and interglacial periods. Previous studies on past processes affecting the current distribution of Dactylorhiza species as well as the history of the polyploid complex formation were based only on molecular data. In the present study the ecological niche modeling (ENM) technique was applied in order to describe the distribution of potential refugia for the selected Dactylorhiza representatives during the Last Glacial Maximum. Additionally, future changes in their potential habitat coverage were measured with regard to three various climatic change scenarios. The maximum entropy method was used to create models of suitable niche distribution. A database of Dactylorhiza localities was prepared on the grounds of information collected from literature and data gathered during field works. Our research indicated that the habitats of majority of the studied taxa will decrease by 2080, except for D. incarnata var. incarnata, for which suitable habitats will increase almost two-fold in the global scale. Moreover, the potential habitats of some taxa are located outside their currently known geographical ranges, e.g. the Aleutian Islands, the western slopes of the Rocky Mountains, Newfoundland, southern Greenland and Iceland. ENM analysis did not confirm that the Balkans, central Europe or central Russia served as the most important refugia for individual representatives of the Dactylorhiza incarnata/maculata complex. Our study rather indicated that the Black Sea coast, southern Apennines and Corsica were the main areas characterized by habitats suitable for most of the taxa. PMID:26599630

  13. Multiscale habitat selection by burrowing owls in black-tailed prairie dog colonies

    Science.gov (United States)

    Lantz, S.J.; Conway, C.J.; Anderson, S.H.

    2007-01-01

    Some populations of western burrowing owls (Athene cunicularia hypugaea) have declined in recent decades. To design and implement effective recovery efforts, we need a better understanding of how distribution and demographic traits are influenced by habitat quality. To this end, we measured spatial patterns of burrowing owl breeding habitat selection within black-tailed prairie dog (Cynomys ludovicianus) colonies in northeastern Wyoming, USA. We compared burrow-, site-, colony-, and landscape-scale habitat parameters between burrowing owl nest burrows (n = 105) and unoccupied burrows (n = 85). We sampled 4 types of prairie dog colonies: 1) owl-occupied, active with prairie dogs (n = 16); 2) owl-occupied, inactive (n = 13); 3) owl-unoccupied, active (n = 14); and 4) owl-unoccupied, inactive (n = 14). We used an information-theoretic approach to examine a set of candidate models of burrowing owl nest-site selection. The model with the most support included variables at all 4 spatial scales, and results were consistent among the 4 types of prairie dog colonies. Nest burrows had longer tunnels, more available burrows within 30 m, and less shrub cover within 30 m, more prairie dog activity within 100 m, and were closer to water than unoccupied burrows. The model correctly classified 76% of cases, all model coefficients were stable, and the model had high predictive ability. Based on our results, we recommend actions to ensure persistence of the remaining prairie dog colonies as an important management strategy for burrowing owl conservation in the Great Plains of North America.

  14. Temporal plasticity in thermal-habitat selection of burbot Lota lota a diel-migrating winter-specialist.

    Science.gov (United States)

    Harrison, P M; Gutowsky, L F G; Martins, E G; Patterson, D A; Cooke, S J; Power, M

    2016-06-01

    In this study, animal-borne telemetry with temperature sensors was coupled with extensive habitat temperature monitoring in a dimictic reservoir, to test the following hypotheses: behavioural thermoregulation occurs throughout the year and temperature selection varies on a diel and seasonal basis, in a winter-specialist diel-migrating fish. Burbot Lota lota demonstrated nightly behavioural thermoregulation throughout the year, with a large seasonal shift between selection for very cold temperatures (hunting and feeding during non-reproductive periods. During daylight hours, while L. lota avoided habitats warmer than optimal for reproduction and feeding during the spawning and non-reproductive periods, respectively, active selection was limited to selection for 4-6° C habitat during the prespawning period. Although behavioural thermoregulation explained the night-time migration, behavioural thermoregulation only partially explained daytime behaviour, indicating that diel migration is best explained by a combination of factors. Thus, thermal-habitat selection was a good predictor of night-time habitat occupancy in a diel-migrating species. Together, these results show that thermal-habitat selection by fishes may be important throughout the year and a more seasonally plastic behaviour than previously recognized. PMID:27125426

  15. Seagrass beds as ocean acidification refuges for mussels? High resolution measurements of pCO2 and O2 in a Zostera marina and Mytilus edulis mosaic habitat

    Directory of Open Access Journals (Sweden)

    V. Saderne

    2015-07-01

    Full Text Available It has been speculated that macrophytes beds might act as a refuge for calcifiers from ocean acidification. In the shallow nearshores of the western Kiel Bay (Baltic Sea, mussel and seagrass beds are interlacing, forming a mosaic habitat. Naturally, the diverse physiological activities of seagrasses and mussels are affected by seawater carbonate chemistry and they locally modify it in return. Calcification by shellfishes is sensitive to seawater acidity; therefore the photosynthetic activity of seagrasses in confined shallow waters creates favorable chemical conditions to calcification at daytime but turn the habitat less favorable or even corrosive to shells at night. In contrast, mussel respiration releases CO2, turning the environment more favorable for photosynthesis by adjacent seagrasses. At the end of summer, these dynamics are altered by the invasion of high pCO2/low O2 coming from the deep water of the Bay. However, it is in summer that mussel spats settle on the leaves of seagrasses until migrating to the permanent habitat where they will grow adult. These early life phases (larvae/spats are considered as most sensitive with regard to seawater acidity. So far, the dynamics of CO2 have never been continuously measured during this key period of the year, mostly due to the technological limitations. In this project we used a combination of state-of-the-art technologies and discrete sampling to obtain high-resolution time-series of pCO2 and O2 at the interface between a seagrass and a mussel patch in Kiel Bay in August and September 2013. From these, we derive the entire carbonate chemistry using statistical models. We found the monthly average pCO2 more than 50 % (approx. 640 μatm for August and September above atmospheric equilibrium right above the mussel patch together with large diel variations of pCO2 within 24 h: 887 ± 331 μatm in August and 742 ± 281 μatm in September (mean ± SD. We observed important daily corrosiveness for

  16. Seagrass beds as ocean acidification refuges for mussels? High resolution measurements of pCO2 and O2 in a Zostera marina and Mytilus edulis mosaic habitat

    Science.gov (United States)

    Saderne, V.; Fietzek, P.; Aßmann, S.; Körtzinger, A.; Hiebenthal, C.

    2015-07-01

    It has been speculated that macrophytes beds might act as a refuge for calcifiers from ocean acidification. In the shallow nearshores of the western Kiel Bay (Baltic Sea), mussel and seagrass beds are interlacing, forming a mosaic habitat. Naturally, the diverse physiological activities of seagrasses and mussels are affected by seawater carbonate chemistry and they locally modify it in return. Calcification by shellfishes is sensitive to seawater acidity; therefore the photosynthetic activity of seagrasses in confined shallow waters creates favorable chemical conditions to calcification at daytime but turn the habitat less favorable or even corrosive to shells at night. In contrast, mussel respiration releases CO2, turning the environment more favorable for photosynthesis by adjacent seagrasses. At the end of summer, these dynamics are altered by the invasion of high pCO2/low O2 coming from the deep water of the Bay. However, it is in summer that mussel spats settle on the leaves of seagrasses until migrating to the permanent habitat where they will grow adult. These early life phases (larvae/spats) are considered as most sensitive with regard to seawater acidity. So far, the dynamics of CO2 have never been continuously measured during this key period of the year, mostly due to the technological limitations. In this project we used a combination of state-of-the-art technologies and discrete sampling to obtain high-resolution time-series of pCO2 and O2 at the interface between a seagrass and a mussel patch in Kiel Bay in August and September 2013. From these, we derive the entire carbonate chemistry using statistical models. We found the monthly average pCO2 more than 50 % (approx. 640 μatm for August and September) above atmospheric equilibrium right above the mussel patch together with large diel variations of pCO2 within 24 h: 887 ± 331 μatm in August and 742 ± 281 μatm in September (mean ± SD). We observed important daily corrosiveness for calcium

  17. Birdsong Acquisition Model by Sexual Selection Focused on the Habitat Density

    Science.gov (United States)

    Fujita, Yohei; Mutoh, Atsuko; Kato, Shohei

    We describe a simulation model based on an avian ecosystem for determining what causes birdsong evolution. It is already known that songbirds communicate with a “birdsong.” This birdsong is used in territorial and courtship behaviors. Some previous researches have suggested that songs related to territorial behaviors should have simple structures while those related to courtship behaviors should have complex ones. We suspect that birdsongs are constantly evolving to achieve a suitable balance between the two behaviors while considering the surrounding environment. We consider avian habitat density to be one of the most important environmental factors influencing birdsong evolution and therefore created different densities in a simulation model. In this paper, we propose a birdsong acquisition model by sexual selection that contains both territorial and courtship behaviors. We conducted simulations with the proposed model and determined that the evolution of birdsongs differs depending on a bird's habitat density. The experimental results suggest that a bird's habitat density influences the structure of birdsongs, as well.

  18. Habitat selection by breeding waterbirds at ponds with size-structured fish populations

    Science.gov (United States)

    Kloskowski, Janusz; Nieoczym, Marek; Polak, Marcin; Pitucha, Piotr

    2010-07-01

    Fish may significantly affect habitat use by birds, either as their prey or as competitors. Fish communities are often distinctly size-structured, but the consequences for waterbird assemblages remain poorly understood. We examined the effects of size structure of common carp ( Cyprinus carpio) cohorts together with other biotic and abiotic pond characteristics on the distribution of breeding waterbirds in a seminatural system of monocultured ponds, where three fish age classes were separately stocked. Fish age corresponded to a distinct fish size gradient. Fish age and total biomass, macroinvertebrate and amphibian abundance, and emergent vegetation best explained the differences in bird density between ponds. Abundance of animal prey other than fish (aquatic macroinvertebrates and larval amphibians) decreased with increasing carp age in the ponds. Densities of ducks and smaller grebes were strongly negatively associated with fish age/size gradient. The largest of the grebes, the piscivorous great crested grebe ( Podiceps cristatus), was the only species that preferred ponds with medium-sized fish and was positively associated with total fish biomass. Habitat selection by bitterns and most rallids was instead strongly influenced by the relative amount of emergent vegetation cover in the ponds. Our results show that fish size structure may be an important cue for breeding habitat choice and a factor affording an opportunity for niche diversification in avian communities.

  19. Photo-orientation regulates seasonal habitat selection in the two-spotted spider mite, Tetranychus urticae.

    Science.gov (United States)

    Suzuki, Takeshi; Kojima, Takeshi; Takeda, Makio; Sakuma, Masayuki

    2013-03-15

    Non-diapausing spider mites (Tetranychus urticae) live on the undersurface of host leaves during summer, but diapausing mites overwinter in dark hibernacula. The light environments of these habitats differ: visible radiation (VIS) but not ultraviolet radiation (UV) reaches the undersurface of leaves, but neither enters dark hibernacula. Thus, mites of either seasonal form could locate their preferred habitat by photo-orientation responses to UV and VIS. To investigate this possibility, we analysed the mites' locomotion behaviour on a virtual field with a programmed chequered pattern of light and dark patches in a micro-locomotion compensator. Both non-diapausing and diapausing mites moved away from UV-illuminated patches into dark patches. Non-diapausing mites moved towards VIS-illuminated patches, whereas diapausing mites did not show a preference. Our results show that non-diapausing mites avoid UV and are attracted to VIS, suggesting that this can guide them beneath a leaf. Diapausing mites simply avoid UV. The lack of a preference for VIS during diapause could be due to changes in carotenoid metabolism, which also involve orange pigmentation of diapausing mites. We consider that a diapause-mediated switch of the response to VIS, together with regular avoidance of UV, plays a key role in the seasonal change of habitat selection in this species. This seasonal polyphenism involves alterations in not only reproductive state and pigmentation, but also in photo-spectral responses.

  20. Habitat Selection and Temporal Abundance Fluctuations of Demersal Cartilaginous Species in the Aegean Sea (Eastern Mediterranean)

    Science.gov (United States)

    Maravelias, Christos D.; Tserpes, George; Pantazi, Maria; Peristeraki, Panagiota

    2012-01-01

    Predicting the occurrence of keystone top predators in a multispecies marine environment, such as the Mediterranean Sea, can be of considerable value to the long-term sustainable development of the fishing industry and to the protection of biodiversity. We analysed fisheries independent scientific bottom trawl survey data of two of the most abundant cartilaginous fish species (Scyliorhinus canicula, Raja clavata) in the Aegean Sea covering an 11-year sampling period. The current findings revealed a declining trend in R. clavata and S. canicula abundance from the late ′90 s until 2004. Habitats with the higher probability of finding cartilaginous fish present were those located in intermediate waters (depth: 200–400 m). The present results also indicated a preferential species' clustering in specific geographic and bathymetric regions of the Aegean Sea. Depth appeared to be one of the key determining factors for the selection of habitats for all species examined. With cartilaginous fish species being among the more biologically sensitive fish species taken in European marine fisheries, our findings, which are based on a standardized scientific survey, can contribute to the rational exploitation and management of their stocks by providing important information on temporal abundance trends and habitat preferences. PMID:22536389

  1. Habitat selection of Guizhou golden monkey (Phinopithecus roxellanae brelichi)in Fanjing Mountain Biosphere Reserve, China

    Institute of Scientific and Technical Information of China (English)

    WUGang; WANGHong-chang; FUHai-wei; ZHAOJing-zhu; YANGYe-qin

    2004-01-01

    Guizhou golden monkey (Phinopithecus roxellanae brelichi) is a peculiar, rare and endangered species. It is distributed most narrowly and requires a rigorous habitat. In this study the habitats of Guizhou Golden Monkey were divided into three habitats: most suitable habitats, suitable habitats and marginally suitable habitats. The characteristics of the vegetation community, environmental factors and extreme environmental factors in the three habitats were systematically analyzed. The seasonal activity rule, activity area and the food characteristic of Guizhou golden monkey were also study at the same time. The results indicate that the evergreen and deciduous broadleaf mixed forest is the optimal living vegetation community for Guizhoug olden Monkey, and the suitable annual temperature is 8-15℃, the extremely lowest temperature is -2.5℃, the extremely highest temperature is 25℃, and the optimal living altitude is 1500-1700 m. In the same area, the higher the vegetation diversitythe more suitable it is for the life of Guizhou golden monkey. Temperature and food are the main habitat factors in determining the activity scope of the guizhou golden monkey community. The Altitude, temperature and the characteristics of the vegetation community are the main limitina factors for habitat selection.

  2. Associations of selected bedding types with incidence rates of subclinical and clinical mastitis in primiparous Holstein dairy cows.

    Science.gov (United States)

    Rowbotham, R F; Ruegg, P L

    2016-06-01

    The objective of this observational study was to determine the association of exposure to selected bedding types with incidence of subclinical (SM) and clinical mastitis (CM) in primiparous Holstein dairy cows housed in identical pens at a single facility. At parturition, primiparous cows were randomly assigned to pens containing freestalls with 1 of 4 bedding materials: (1) deep-bedded new sand (NES, n=27 cows), (2) deep-bedded recycled sand (RS, n=25 cows), (3) deep-bedded manure solids (DBMS, n=31 cows), and (4) shallow-bedded manure solids over foam-core mattresses (SBMS, n=26 cows). For 12mo, somatic cell counts of quarter milk samples were determined every 28d and duplicate quarter milk samples were collected for microbiological analysis from all quarters with SM (defined as somatic cell count >200,000 cells/mL). During this period, duplicate quarter milk samples were also collected for microbial analysis from all cases of CM. For an additional 16mo, cases of CM were recorded; however, no samples were collected. Quarter days at risk (62,980) were distributed among bedding types and most quarters were enrolled for >150d. Of 135 cases of SM, 63% resulted in nonsignificant growth and 87% of recovered pathogens (n=33) were identified as coagulase-negative staphylococci. The distribution of etiologies of pathogens recovered from cases of SM was associated with bedding type. Coagulase-negative staphylococci were recovered from 12, 38, 11, and 46% of quarters with SM from cows in pens containing NES, RS, DBMS, and SBMS, respectively. A result of nonsignificant growth was obtained for 81, 59, 89, and 46% of quarters with SM from cows in pens containing NES, RS, DBMS, and SBMS, respectively. Quarters of primiparous cows bedded with NES tended to have greater survival time to incidence of CM than quarters of primiparous cows bedded with RS or DBMS. PMID:27060828

  3. Habitat selection of the Mauritian lowland forest day gecko at multiple spatial scales: A baseline for translocation

    Directory of Open Access Journals (Sweden)

    Steeves Buckland

    2014-08-01

    Full Text Available Of 30 known subpopulations of Phelsuma guimbeaui, 18 are in patches of exotic forest and are predicted to disappear in the next decade. One possible means of mitigating the reduction in genetic diversity associated with the loss of subpopulations is to translocate “at risk” subpopulations to more secure habitats. Prior to any such intervention, it is important to identify a species’ basic ecological needs. We had three main objectives: to calculate home range sizes of adult geckos; characterise habitat selection among age groups; and identify the order of importance of each habitat predictor. Habitat selection of P. guimbeaui was explored at the population, home range and microhabitat levels. Males had larger home ranges than females, and overlapped temporally with more females than males. We showed that habitat selection differed between age groups. In order of importance, tree diversity, tree species, tree height, trunk dbh and cavity density were important habitat predictors. We discuss how these data can be used to inform the choice of sites for the translocation of threatened subpopulations. Our results also highlight the importance of undertaking habitat restoration for the long-term conservation of the 12 subpopulations that survive in patches of endemic forest.

  4. Quantity, structure, and habitat selection of natural spawning reefs by walleyes in a north temperate lake: A multiscale analysis

    Science.gov (United States)

    Raabe, Joshua K.; Bozek, Michael A.

    2012-01-01

    Spawning habitat, the cornerstone of self-sustaining, naturally reproducing walleyeSander vitreus populations, has received limited quantitative research. Our goal was to quantitatively describe the structure and quantity of natural walleye spawning habitat and evaluate potential selection of habitat in Big Crooked Lake, Wisconsin. In 2004 and 2005, we located and delineated walleye egg deposition polygons through visual snorkel and scuba surveys. We also delineated recently deposited, adhesive egg patches daily along one spawning reef in 2005. To determine habitat selection, we quantified and compared spawning and lakewide available habitat at different scales. In both years, walleyes used similar spawning habitat, including three geomorphic types: linear shorelines, a point bar, and an island. Walleyes used only 14% of the entire lake shoreline and 39% of the shoreline comprised of gravel (6.4–76.0 mm), cobble (76.1–149.9 mm), or coarser substrates for spawning in 2005, indicating selection of specific spawning habitat. Lakewide, walleyes spawned close to shore (outer egg deposition polygon boundary mean distance = 2.7 m), in shallow water (outer egg deposition polygon boundary mean depth = 0.3 m), and over gravel substrate (percent coverage mean = 64.3) having low embeddedness (mean = 1.30). Our best nearshore (0–13-m) resource selection function predicted an increase in the relative probability of egg deposition with the increasing abundance of gravel, cobble, and rubble (150.0–303.9-mm) substrates and a decrease with increasing distance from shore and water depth (89.9% overall correct classification). Adhesive egg patches confirmed that walleyes actively chose nearshore, shallow-water, and coarse-substrate spawning habitat. The quantitative habitat information and predictive models will assist biologists in developing walleye spawning reef protection strategies and potentially aid in designing and evaluating artificial spawning reefs.

  5. Heat, safety or solitude? Using habitat selection experiments to identify a lizard's priorities.

    Science.gov (United States)

    Downes; Shine

    1998-05-01

    Laboratory experiments with a rock-dwelling nocturnal gecko, Oedura lesueurii, showed that retreat-site selection (and other behaviours) are affected by the interplay between thermal benefits, social advantages and avoidance of predators. Velvet geckos were highly selective in habitat choice: they preferred artificial retreat-sites that mimic the thermal properties of natural rocks in full sun rather than those that mimic rocks in full shade; mature male geckos rarely shared retreat-sites with other adult males; and these lizards strongly avoided retreat-sites covered with the scent of a natural predator (the broadheaded snake, Hoplocephalus bungaroides). After documenting these preferences, we carried out additional trials in which two or more of these factors co-occurred, as is often the case in nature. Social dominance interacted with thermal benefits in determining retreat-site selection, with smaller (subordinate) males forced to use cooler retreat-sites when larger (dominant) males were present. Avoidance of predators was a higher priority than thermoregulation: the lizards would forego a warmer retreat-site with predator scent in favour of a cooler, unscented one. There was also an interplay between social dominance and predator scent: smaller males were forced to use either predator-scented retreat-sites or no retreat-site when larger males were present. General activity levels, and the frequencies of specific behavioural acts, also shifted in response to social and predator-scent cues. Our study emphasizes the complexity of habitat-selection behaviour in these lizards, and clarifies the criteria used in retreat-site selection when (as is commonly the case) the animal must choose between conflicting priorities. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour.

  6. Movements, home-range size and habitat selection of mallards during autumn migration.

    Directory of Open Access Journals (Sweden)

    Daniel Bengtsson

    Full Text Available The mallard (Anas platyrhynchos is a focal species in game management, epidemiology and ornithology, but comparably little research has focused on the ecology of the migration seasons. We studied habitat use, time-budgets, home-range sizes, habitat selection, and movements based on spatial data collected with GPS devices attached to wild mallards trapped at an autumn stopover site in the Northwest European flyway. Sixteen individuals (13 males, 3 females were followed for 15-38 days in October to December 2010. Forty-nine percent (SD = 8.4% of the ducks' total time, and 85% of the day-time (SD = 28.3%, was spent at sheltered reefs and bays on the coast. Two ducks used ponds, rather than coast, as day-roosts instead. Mallards spent most of the night (76% of total time, SD = 15.8% on wetlands, mainly on alvar steppe, or in various flooded areas (e.g. coastal meadows. Crop fields with maize were also selectively utilized. Movements between roosting and foraging areas mainly took place at dawn and dusk, and the home-ranges observed in our study are among the largest ever documented for mallards (mean  = 6,859 ha; SD = 5,872 ha. This study provides insights into relatively unknown aspects of mallard ecology. The fact that autumn-staging migratory mallards have a well-developed diel activity pattern tightly linked to the use of specific habitats has implications for wetland management, hunting and conservation, as well as for the epidemiology of diseases shared between wildlife and domestic animals.

  7. Biomass Fuel and Combustion Conditions Selection in a Fixed Bed Combustor

    Directory of Open Access Journals (Sweden)

    María E. Arce

    2013-11-01

    Full Text Available The biomass market has experienced an increase in development, leading to research and development efforts that are focused on determining optimal biofuel combustion conditions. Biomass combustion is a complex process that involves divergent parameters and thus requires the use of advanced analysis methods. This study proposes combining grey relational analysis (GRA and error propagation theory (EPT to select a biofuel and its optimal combustion conditions. This research will study three biofuels that are currently used in a region of South Europe (Spain, and the most important variables that affect combustion are the ignition front propagation speed and the highest temperature that is reached at the fixed bed combustor. The results demonstrate that a combination of both theories for the analysis of solid-state thermochemical phenomena enables a fast and simple way of choosing the best configuration for each fuel.

  8. Selecting a Conservation Surrogate Species for Small Fragmented Habitats Using Ecological Niche Modelling.

    Science.gov (United States)

    Nekaris, K Anne-Isola; Arnell, Andrew P; Svensson, Magdalena S

    2015-01-01

    Flagship species are traditionally large, charismatic animals used to rally conservation efforts. Accepted flagship definitions suggest they need only fulfil a strategic role, unlike umbrella species that are used to shelter cohabitant taxa. The criteria used to select both flagship and umbrella species may not stand up in the face of dramatic forest loss, where remaining fragments may only contain species that do not suit either set of criteria. The Cinderella species concept covers aesthetically pleasing and overlooked species that fulfil the criteria of flagships or umbrellas. Such species are also more likely to occur in fragmented habitats. We tested Cinderella criteria on mammals in the fragmented forests of the Sri Lankan Wet Zone. We selected taxa that fulfilled both strategic and ecological roles. We created a shortlist of ten species, and from a survey of local perceptions highlighted two finalists. We tested these for umbrella characteristics against the original shortlist, utilizing Maximum Entropy (MaxEnt) modelling, and analysed distribution overlap using ArcGIS. The criteria highlighted Loris tardigradus tardigradus and Prionailurus viverrinus as finalists, with the former having highest flagship potential. We suggest Cinderella species can be effective conservation surrogates especially in habitats where traditional flagship species have been extirpated. PMID:26479135

  9. Selecting a Conservation Surrogate Species for Small Fragmented Habitats Using Ecological Niche Modelling

    Directory of Open Access Journals (Sweden)

    K. Anne-Isola Nekaris

    2015-01-01

    Full Text Available Flagship species are traditionally large, charismatic animals used to rally conservation efforts. Accepted flagship definitions suggest they need only fulfil a strategic role, unlike umbrella species that are used to shelter cohabitant taxa. The criteria used to select both flagship and umbrella species may not stand up in the face of dramatic forest loss, where remaining fragments may only contain species that do not suit either set of criteria. The Cinderella species concept covers aesthetically pleasing and overlooked species that fulfil the criteria of flagships or umbrellas. Such species are also more likely to occur in fragmented habitats. We tested Cinderella criteria on mammals in the fragmented forests of the Sri Lankan Wet Zone. We selected taxa that fulfilled both strategic and ecological roles. We created a shortlist of ten species, and from a survey of local perceptions highlighted two finalists. We tested these for umbrella characteristics against the original shortlist, utilizing Maximum Entropy (MaxEnt modelling, and analysed distribution overlap using ArcGIS. The criteria highlighted Loris tardigradus tardigradus and Prionailurus viverrinus as finalists, with the former having highest flagship potential. We suggest Cinderella species can be effective conservation surrogates especially in habitats where traditional flagship species have been extirpated.

  10. Selective mixed-bed solid phase extraction of atrazine herbicide from environmental water samples using molecularly imprinted polymer.

    Science.gov (United States)

    Zarejousheghani, Mashaalah; Fiedler, Petra; Möder, Monika; Borsdorf, Helko

    2014-11-01

    A novel approach for the selective extraction of organic target compounds from water samples has been developed using a mixed-bed solid phase extraction (mixed-bed SPE) technique. The molecularly imprinted polymer (MIP) particles are embedded in a network of silica gel to form a stable uniform porous bed. The capabilities of this method are demonstrated using atrazine as a model compound. In comparison to conventional molecularly imprinted-solid phase extraction (MISPE), the proposed mixed-bed MISPE method in combination with gas chromatography-mass spectrometry (GC-MS) analysis enables more reproducible and efficient extraction performance. After optimization of operational parameters (polymerization conditions, bed matrix ingredients, polymer to silica gel ratio, pH of the sample solution, breakthrough volume plus washing and elution conditions), improved LODs (1.34 µg L(-1) in comparison to 2.25 µg L(-1) obtained using MISPE) and limits of quantification (4.5 µg L(-1) for mixed-bed MISPE and 7.5 µg L(-1) for MISPE) were observed for the analysis of atrazine. Furthermore, the relative standard deviations (RSDs) for atrazine at concentrations between 5 and 200 µg L(-1) ranged between 1.8% and 6.3% compared to MISPE (3.5-12.1%). Additionally, the column-to-column reproducibility for the mixed-bed MISPE was significantly improved to 16.1%, compared with 53% that was observed for MISPE. Due to the reduced bed-mass sorbent and at optimized conditions, the total amount of organic solvents required for conditioning, washing and elution steps reduced from more than 25 mL for conventional MISPE to less than 2 mL for mixed-bed MISPE. Besides reduced organic solvent consumption, total sample preparation time of the mixed-bed MISPE method relative to the conventional MISPE was reduced from more than 20 min to less than 10 min. The amount of organic solvent required for complete elution diminished from 3 mL (conventional MISPE) to less than 0.4 mL with the mixed-bed

  11. Reaction engineering simulations of a fluidized-bed reactor for selective oxidation of fluorene to 9-fluorenone

    Energy Technology Data Exchange (ETDEWEB)

    Mleczko, L. (Bochum Univ. (Germany). Lehrstuhl fuer Technische Chemie); Pannek, U. (Bochum Univ. (Germany). Lehrstuhl fuer Technische Chemie); Baerns, M. (Bochum Univ. (Germany). Lehrstuhl fuer Technische Chemie)

    1994-06-01

    The catalytic oxidation of fluorene to 9-fluorenone in a fluidized-bed reactor was investigated by modeling of the reactor and simulation of its performance. The ''Bubble Assemblage Model'' of Kato and Wen, the ''Bubbling Bed Model'' of Kunii and Levenspiel and the ''Countercurrent Backmixing Model'' of Potter were applied. From a comparison of simulation results obtained by the various fluidized-bed models and a fixed-bed model conclusions were drawn about the influence of interphase mass transfer and gas backmixing on the conversion of fluorene and selectivity of 9-fluorenone formation. Furthermore, the dependence of conversion and selectivity on temperature and hydrodynamic conditions was investigated. In particular, the implications of a change of hydrodynamic conditions for scale-up were analysed. The highest yield of 9-fluorenone predicted for a bench-scale fluidized bed amounted to 88% (X[sub F] = 97%, S[sub NON] = 91%). This yield was lower than in a fixed-bed reactor (Y[sub NON] = 92%, X[sub F] = 99%, S[sub NON] = 93%). A further drop of the yield was predicted when scaling-up from a bench-scale reactor to a commercial size unit (Y[sub NON] = 54%, X[sub F] = 86%, S[sub NON] = 63%). (orig.)

  12. To kill, stay or flee: the effects of lions and landscape factors on habitat and kill site selection of cheetahs in South Africa.

    Directory of Open Access Journals (Sweden)

    Susana Rostro-García

    Full Text Available Understanding how animals utilize available space is important for their conservation, as it provides insight into the ecological needs of the species, including those related to habitat, prey and inter and intraspecific interactions. We used 28 months of radio telemetry data and information from 200 kill locations to assess habitat selection at the 3rd order (selection of habitats within home ranges and 4th order (selection of kill sites within the habitats used of a reintroduced population of cheetahs Acinonyx jubatus in Phinda Private Game Reserve, South Africa. Along with landscape characteristics, we investigated if lion Panthera leo presence affected habitat selection of cheetahs. Our results indicated that cheetah habitat selection was driven by a trade-off between resource acquisition and lion avoidance, and the balance of this trade-off varied with scale: more open habitats with high prey densities were positively selected within home ranges, whereas more closed habitats with low prey densities were positively selected for kill sites. We also showed that habitat selection, feeding ecology, and avoidance of lions differed depending on the sex and reproductive status of cheetahs. The results highlight the importance of scale when investigating a species' habitat selection. We conclude that the adaptability of cheetahs, together with the habitat heterogeneity found within Phinda, explained their success in this small fenced reserve. The results provide information for the conservation and management of this threatened species, especially with regards to reintroduction efforts in South Africa.

  13. Habitat selection of two gobies (Microgobius gulosus, Gobiosoma robustum): influence of structural complexity, competitive interactions and presence of a predator

    Science.gov (United States)

    Schofield, P.J.

    2003-01-01

    Herein I compare the relative importance of preference for structurally complex habitat against avoidance of competitors and predators in two benthic fishes common in the Gulf of Mexico. The code goby Gobiosoma robustum Ginsburg and clown goby Microgobius gulosus (Girard) are common, ecologically similar fishes found throughout the Gulf of Mexico and in the southeastern Atlantic Ocean. In Florida Bay, these fishes exhibit habitat partitioning: G. robustum is most abundant in seagrass-dominated areas while M. gulosus is most abundant in sparsely vegetated habitats. In a small-scale field survey, I documented the microhabitat use of these species where their distributions overlap. In a series of laboratory experiments, I presented each species with structured (artificial seagrass) versus nonstructured (bare sand) habitats and measured their frequency of choosing either habitat type. I then examined the use of structured versus nonstructured habitats when the two species were placed together in a mixed group. Finally, I placed a predator (Opsanus beta) in the experimental aquaria to determine how its presence influenced habitat selection. In the field, G. robustum was more abundant in seagrass and M. gulosus was more abundant in bare mud. In the laboratory, both species selected grass over sand in allopatry. However, in sympatry, M. gulosus occupied sand more often when paired with G. robustum than when alone. G. robustum appears to directly influence the habitat choice of M. gulosus: It seems that M. gulosus is pushed out of the structured habitat that is the preferred habitat of G. robustum. Thus, competition appears to modify the habitat selection of these species when they occur in sympatry. Additionally, the presence of the toadfish was a sufficient stimulus to provoke both M. gulosus and G. robustum to increase their selection for sand (compared to single-species treatments). Distribution patterns of M. gulosus and G. robustum

  14. Balancing energy budget in a central-place forager: which habitat to select in a heterogeneous environment?

    Directory of Open Access Journals (Sweden)

    Martin Patenaude-Monette

    Full Text Available Foraging animals are influenced by the distribution of food resources and predation risk that both vary in space and time. These constraints likely shape trade-offs involving time, energy, nutrition, and predator avoidance leading to a sequence of locations visited by individuals. According to the marginal-value theorem (MVT, a central-place forager must either increase load size or energy content when foraging farther from their central place. Although such a decision rule has the potential to shape movement and habitat selection patterns, few studies have addressed the mechanisms underlying habitat use at the landscape scale. Our objective was therefore to determine how Ring-billed gulls (Larus delawarensis select their foraging habitats while nesting in a colony located in a heterogeneous landscape. Based on locations obtained by fine-scale GPS tracking, we used resource selection functions (RSFs and residence time analyses to identify habitats selected by gulls for foraging during the incubation and brood rearing periods. We then combined this information to gull survey data, feeding rates, stomach contents, and calorimetric analyses to assess potential trade-offs. Throughout the breeding season, gulls selected landfills and transhipment sites that provided higher mean energy intake than agricultural lands or riparian habitats. They used landfills located farther from the colony where no deterrence program had been implemented but avoided those located closer where deterrence measures took place. On the other hand, gulls selected intensively cultured lands located relatively close to the colony during incubation. The number of gulls was then greater in fields covered by bare soil and peaked during soil preparation and seed sowing, which greatly increase food availability. Breeding Ring-billed gulls thus select habitats according to both their foraging profitability and distance from their nest while accounting for predation risk. This

  15. Habitat suitability criteria via parametric distributions: estimation, model selection and uncertainty

    Science.gov (United States)

    Som, Nicholas A.; Goodman, Damon H.; Perry, Russell W.; Hardy, Thomas B.

    2016-01-01

    Previous methods for constructing univariate habitat suitability criteria (HSC) curves have ranged from professional judgement to kernel-smoothed density functions or combinations thereof. We present a new method of generating HSC curves that applies probability density functions as the mathematical representation of the curves. Compared with previous approaches, benefits of our method include (1) estimation of probability density function parameters directly from raw data, (2) quantitative methods for selecting among several candidate probability density functions, and (3) concise methods for expressing estimation uncertainty in the HSC curves. We demonstrate our method with a thorough example using data collected on the depth of water used by juvenile Chinook salmon (Oncorhynchus tschawytscha) in the Klamath River of northern California and southern Oregon. All R code needed to implement our example is provided in the appendix. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  16. Habitat selection of the Tibetan Snow Cock Tetraogallus tibetanus in the spring in Lhasa

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The habitat selection of Tibetan Snow Cocks in shrub vegetation was investigated in Lhasa,Tibet,China,between March and April,2005.Fourteen parameters were measured.These include altitude,slope,slope aspect,slope position,vegetation cover,plant type and other environmental parameters.Results show that Snow Cocks favor foraging in areas where vegetation cover was small and close to the residents' houses.Supplementary food supplied by humans has caused Snow Cocks to decrease their foraging range.Snow Cocks also favor roosting in areas with low vegetation,sparse grass,short grass,large rocks and close to houses.The Snow Cocks' activity in the study areas show a close relationship with human activities.

  17. Habitat Selection and Post-Release Movement of Reintroduced Brown Treecreeper Individuals in Restored Temperate Woodland

    OpenAIRE

    Victoria A Bennett; Doerr, Veronica A. J.; Erik D Doerr; Manning, Adrian D.; Lindenmayer, David B; Hwan-Jin Yoon

    2012-01-01

    It is essential to choose suitable habitat when reintroducing a species into its former range. Habitat quality may influence an individual's dispersal decisions and also ultimately where they choose to settle. We examined whether variation in habitat quality (quantified by the level of ground vegetation cover and the installation of nest boxes) influenced the movement, habitat choice and survival of a reintroduced bird species. We experimentally reintroduced seven social groups (43 individual...

  18. Resource selection by the California condor (Gymnogyps californianus relative to terrestrial-based habitats and meteorological conditions.

    Directory of Open Access Journals (Sweden)

    James W Rivers

    Full Text Available Condors and vultures are distinct from most other terrestrial birds because they use extensive soaring flight for their daily movements. Therefore, assessing resource selection by these avian scavengers requires quantifying the availability of terrestrial-based habitats, as well as meteorological variables that influence atmospheric conditions necessary for soaring. In this study, we undertook the first quantitative assessment of habitat- and meteorological-based resource selection in the endangered California condor (Gymnogyps californianus within its California range and across the annual cycle. We found that condor use of terrestrial areas did not change markedly within the annual cycle, and that condor use was greatest for habitats where food resources and potential predators could be detected and where terrain was amenable for taking off from the ground in flight (e.g., sparse habitats, coastal areas. Condors originating from different release sites differed in their use of habitat, but this was likely due in part to variation in habitats surrounding release sites. Meteorological conditions were linked to condor use of ecological subregions, with thermal height, thermal velocity, and wind speed having both positive (selection and negative (avoidance effects on condor use in different areas. We found little evidence of systematic effects between individual characteristics (i.e., sex, age, breeding status or components of the species management program (i.e., release site, rearing method relative to meteorological conditions. Our findings indicate that habitat type and meteorological conditions can interact in complex ways to influence condor resource selection across landscapes, which is noteworthy given the extent of anthropogenic stressors that may impact condor populations (e.g., lead poisoning, wind energy development. Additional studies will be valuable to assess small-scale condor movements in light of these stressors to help minimize

  19. Improving accuracy of overhanging structures for selective laser melting through reliability characterization of single track formation on thick powder beds

    DEFF Research Database (Denmark)

    Mohanty, Sankhya; Hattel, Jesper Henri

    2016-01-01

    Repeatability and reproducibility of parts produced by selective laser melting is a standing issue, and coupled with a lack of standardized quality control presents a major hindrance towards maturing of selective laser melting as an industrial scale process. Consequently, numerical process...... modelling has been adopted towards improving the predictability of the outputs from the selective laser melting process. Establishing the reliability of the process, however, is still a challenge, especially in components having overhanging structures.In this paper, a systematic approach towards...... establishing reliability of overhanging structure production by selective laser melting has been adopted. A calibrated, fast, multiscale thermal model is used to simulate the single track formation on a thick powder bed. Single tracks are manufactured on a thick powder bed using same processing parameters...

  20. No Habitat Selection during Spring Migration at a Meso-Scale Range across Mosaic Landscapes: A Case Study with the Woodcock (Scolopax rusticola)

    Science.gov (United States)

    Crespo, Ariñe; Rodrigues, Marcos; Telletxea, Ibon; Ibáñez, Rubén; Díez, Felipe; Tobar, Joseba F.; Arizaga, Juan

    2016-01-01

    Success of migration in birds in part depends on habitat selection. Overall, it is still poorly known whether there is habitat selection amongst landbird migrants moving across landscapes. Europe is chiefly covered by agro-forestry mosaic landscapes, so migratory species associated to either agricultural landscapes or woodland habitats should theoretically find suitable stopover sites along migration. During migration from wintering to breeding quarters, woodcocks (Scolopax rusticola) tagged with PTT satellite-tracking transmitters were used to test for the hypothesis that migrants associated to agro-forest habitats have no habitat selection during migration, at a meso-scale level. Using a GIS platform we extracted at a meso-scale range habitat cover at stopover localities. Results obtained from comparisons of soil covers between points randomly selected and true stopover localities sites revealed, as expected, the species may not select for particular habitats at a meso-scale range, because the habitat (or habitats) required by the species can be found virtually everywhere on their migration route. However, those birds stopping over in places richer in cropland or mosaic habitats including both cropland and forest and with proportionally less closed forest stayed for longer than in areas with lower surfaces of cropland and mosaic and more closed forest. This suggests that areas rich in cropland or mosaic habitat were optimal. PMID:27002975

  1. No Habitat Selection during Spring Migration at a Meso-Scale Range across Mosaic Landscapes: A Case Study with the Woodcock (Scolopax rusticola).

    Science.gov (United States)

    Crespo, Ariñe; Rodrigues, Marcos; Telletxea, Ibon; Ibáñez, Rubén; Díez, Felipe; Tobar, Joseba F; Arizaga, Juan

    2016-01-01

    Success of migration in birds in part depends on habitat selection. Overall, it is still poorly known whether there is habitat selection amongst landbird migrants moving across landscapes. Europe is chiefly covered by agro-forestry mosaic landscapes, so migratory species associated to either agricultural landscapes or woodland habitats should theoretically find suitable stopover sites along migration. During migration from wintering to breeding quarters, woodcocks (Scolopax rusticola) tagged with PTT satellite-tracking transmitters were used to test for the hypothesis that migrants associated to agro-forest habitats have no habitat selection during migration, at a meso-scale level. Using a GIS platform we extracted at a meso-scale range habitat cover at stopover localities. Results obtained from comparisons of soil covers between points randomly selected and true stopover localities sites revealed, as expected, the species may not select for particular habitats at a meso-scale range, because the habitat (or habitats) required by the species can be found virtually everywhere on their migration route. However, those birds stopping over in places richer in cropland or mosaic habitats including both cropland and forest and with proportionally less closed forest stayed for longer than in areas with lower surfaces of cropland and mosaic and more closed forest. This suggests that areas rich in cropland or mosaic habitat were optimal.

  2. How predictability of feeding patches affects home range and foraging habitat selection in avian social scavengers?

    Directory of Open Access Journals (Sweden)

    Sophie Monsarrat

    Full Text Available Feeding stations are commonly used to sustain conservation programs of scavengers but their impact on behaviour is still debated. They increase the temporal and spatial predictability of food resources while scavengers have supposedly evolved to search for unpredictable resources. In the Grands Causses (France, a reintroduced population of Griffon vultures Gyps fulvus can find carcasses at three types of sites: 1. "light feeding stations", where farmers can drop carcasses at their farm (spatially predictable, 2. "heavy feeding stations", where carcasses from nearby farms are concentrated (spatially and temporally predictable and 3. open grasslands, where resources are randomly distributed (unpredictable. The impact of feeding stations on vulture's foraging behaviour was investigated using 28 GPS-tracked vultures. The average home range size was maximal in spring (1272 ± 752 km(2 and minimal in winter (473 ± 237 km(2 and was highly variable among individuals. Analyses of home range characteristics and feeding habitat selection via compositional analysis showed that feeding stations were always preferred compared to the rest of the habitat where vultures can find unpredictable resources. Feeding stations were particularly used when resources were scarce (summer or when flight conditions were poor (winter, limiting long-ranging movements. However, when flight conditions were optimal, home ranges also encompassed large areas of grassland where vultures could find unpredictable resources, suggesting that vultures did not lose their natural ability to forage on unpredictable resources, even when feeding stations were available. However during seasons when food abundance and flight conditions were not limited, vultures seemed to favour light over heavy feeding stations, probably because of the reduced intraspecific competition and a pattern closer to the natural dispersion of resources in the landscape. Light feeding stations are interesting tools

  3. Perch-height specific predation on tropical lizard clay models: implications for habitat selection in mainland neotropical lizards.

    Science.gov (United States)

    Steffen, John E

    2009-09-01

    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. PMID:19928477

  4. Summer habitat selection by striped bass, Morone Saxatilis, in Cherokee Reservoir, Tennessee, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Waddle, H.R.; Coutant, C.C.; Wilson, J.L.

    1980-02-01

    Summer habitat selection patterns of 18 adult striped bass (Morone saxatilis) in Cherokee Reservoir were monitored with externally attached temperature-sensing acoustic or radio transmitters from June through September 1977. Mortalities of adult striped bass in this reservoir were hypothesized to be related to high summer temperatures and low dissolved oxygen (DO). The inhabited areas or refuges differed from noninhabited areas by maintaining temperatures less than or equal to 22 C and DO concentrations greater than 5 mg/liter. Total water hardness, pH, and water transparency were not significantly different among refuges and noninhabited areas. Movement of fish outside refuges occurred more frequently and for longer periods during June when the summer pattern of high temperatures and low DO was less severe. Fish experienced temperatures between 15 and 27 C with mean temperatures of individuals ranging from 18.5 to 22.0 C. Several tagged fish migrated outside the refuges and selected the lowest available temperature, generally near 21 C, even though DO concentrations at these temperatures were 3 mg/liter or less. Long-term survival of tagged and nontagged fish outside refuges was undetermined because no fish were tracked outside a refuge for more than 12 days without being lost. This study indicates that temperature strongly influences the behavior of striped bass and that adults of this species may have a thermal preferendum of approximately 21 C.

  5. Noise-Dependent Fish Distribution in Kelp Beds.

    Science.gov (United States)

    Zhang, Xuguang; Guo, Hongy; Wang, Zhenhua; Pan, Yingjie; Song, Jiakun

    2016-01-01

    The marine marbled rockfish Sebastiscus marmoratus is dependent on kelp beds and rocks for survival and reproduction. We found that sound production and hearing sensitivity in S. marmoratus are closely matched in the frequency domain. We also found that the juvenile rockfish prefers the habitat of the larger macroalgae Sargassum horueri rather than the habitat containing the smaller algae Ulva pertusa where the adult rockfish prefers to live. Our underwater noise recording data from these two habitats indicate that their spectra of the background noise have different values. The results suggest that the acoustic cues may be critical for pelagic larvae when selecting the preferential habitat in which to settle. PMID:26611095

  6. Staying cool in a changing landscape: the influence of maximum daily ambient temperature on grizzly bear habitat selection.

    Science.gov (United States)

    Pigeon, Karine E; Cardinal, Etienne; Stenhouse, Gordon B; Côté, Steeve D

    2016-08-01

    To fulfill their needs, animals are constantly making trade-offs among limiting factors. Although there is growing evidence about the impact of ambient temperature on habitat selection in mammals, the role of environmental conditions and thermoregulation on apex predators is poorly understood. Our objective was to investigate the influence of ambient temperature on habitat selection patterns of grizzly bears in the managed landscape of Alberta, Canada. Grizzly bear habitat selection followed a daily and seasonal pattern that was influenced by ambient temperature, with adult males showing stronger responses than females to warm temperatures. Cutblocks aged 0-20 years provided an abundance of forage but were on average 6 °C warmer than mature conifer stands and 21- to 40-year-old cutblocks. When ambient temperatures increased, the relative change (odds ratio) in the probability of selection for 0- to 20-year-old cutblocks decreased during the hottest part of the day and increased during cooler periods, especially for males. Concurrently, the probability of selection for 21- to 40-year-old cutblocks increased on warmer days. Following plant phenology, the odds of selecting 0- to 20-year-old cutblocks also increased from early to late summer while the odds of selecting 21- to 40-year-old cutblocks decreased. Our results demonstrate that ambient temperatures, and therefore thermal requirements, play a significant role in habitat selection patterns and behaviour of grizzly bears. In a changing climate, large mammals may increasingly need to adjust spatial and temporal selection patterns in response to thermal constraints.

  7. Home range, habitat selection, and movements of California black rails at tidal marshes at San Francisco Bay, California

    Science.gov (United States)

    Tsao, Danika C.; Takekawa, John Y.; Woo, Isa; Yee, Julie L.; Evens, Jules G.

    2009-01-01

    Little is known about the movements and habitat selection of California Black Rails (Laterallus jamaicensis coturniculus) in coastal California. We captured 130 Black Rails, of which we radio-marked 48, in tidal marshes in San Francisco Bay during 2005 and 2006. Our objective was to examine their home ranges, movements, and habitat selection to improve the species' conservation. The mean fixed-kernel home range was 0.59 ha, the mean core area was 0.14 ha. Home ranges and core areas did not differ by year or site. Males had significantly larger home ranges and core areas than did females. All sites combined, Black Rails used areas with > or = 94% total vegetative cover, with perennial pickleweed (Sarcocornia pacifica) the dominant plant. The rails' habitat selection varied by year and site but not by sex. A multivariate analysis of variance indicated that Black Rails selected areas with pickleweed taller and denser than average, greater cover and height of alkali bulrush (Bolboschoenus maritimus) and common saltgrass (Distichlis spicata), more stems between 20 and 30 cm above the ground, maximum vegetation height, and shorter distance to refugia. On average, Black Rails moved 27.6 +/- 1.8 (SE) m daily and 38.4 +/- 5.5 m during extreme high tides. Understanding the California Black Rail's movements, home range, and habitat use is critical for management to benefit the species.

  8. Home range, habitat selection, and foraging rhythm in Mauritanian spoonbills (Platalea leucorodia balsaci) : A satellite tracking study

    NARCIS (Netherlands)

    El-Hacen, El-Hacen Mohamed; Overdijk, Otto; Lok, Tamar; Olff, Han; Piersma, Theunis

    2013-01-01

    Mauritanian Spoonbills (Platalea leucorodia balsaci) only breed at Banc d'Arguin, Mauritania, West Africa. Their populations have declined; however, nothing is known about possible ecological factors involved, including their primary food and foraging habits. Home range sizes, habitat selection, and

  9. Fine-scale habitat selection of crabeater seals as determined by diving behavior

    Science.gov (United States)

    Burns, J. M.; Hindell, M. A.; Bradshaw, C. J. A.; Costa, D. P.

    2008-02-01

    zooplankton were dispersed and light levels low, foraging activity was less frequent and seals concentrated their diving closer to the surface over a broader range of habitat depths. As individual seals moved an average of only 4.1±1.4 km between daytime and nighttime positions, these results suggest that crabeater seals diving along the Western Antarctic Peninsula select areas of high bathymetric gradients so that they can maximize foraging success over a 24-h cycle without the need to travel long distances. However, annual differences in behavior and the generally low amount of deviation explained by models also suggests that seals vary their diving behavior in response to finer-scale biological, temporal, and/or physical features that were not monitored as part of this study.

  10. Coal resources of selected coal beds and zones in the northern and central Appalachian Basin

    Energy Technology Data Exchange (ETDEWEB)

    Leslie Ruppert; Susan Tewalt; Linda Bragg

    2002-02-01

    The U.S. Geological Survey (USGS) is completing a National Coal Resource Assessment of five coal-producing regions of the United States, including the Appalachian Basin. The USGS, in cooperation with the State geological surveys of Kentucky, Maryland, Ohio, Pennsylvania, Virginia, and West Virginia, has completed a digital coal resource assessment of five of the top-producing coal beds and coal zones in the northern and central Appalachian Basin coal regions -- the Pittsburgh coal bed, the Upper Freeport coal bed, the Fire Clay and Pond Creek coal zones, and the Pocahontas No. 3 coal bed. Of the 93 billion short tons of original coal in these units, about 66 billion short tons remain. 2 refs., 5 figs., 2 tabs.

  11. Distribution and shell selection by two hermit crabs in different habitats on Egyptian Red Sea Coast

    Science.gov (United States)

    El-Kareem Ismail, Tarek Gad

    2010-05-01

    The present work aims to assess the spatial distribution, analyze shell utilization, shell fitness and determine the effect of coexistence of two hermit crabs Calcinus latens and Clibanarius signatus on used shell resources in various habitats on the Red Sea Coast. Also, to determine the choice of shells and investigate the shell species preference of C. latens and C. signatus in the laboratory. The hermit crabs C. latens and C. signatus were found to occupy shells of 39 gastropod species. The most commonly occupied gastropod shells are those belonging to genera Strombus, Nerita, Cerithium and Planaxis. The results showed that crab individuals utilized mainly the shell with elongate aperture. Laboratory experiments showed that two crab species preferred shells of Strombus followed by Cerithium and Nerita when offered shells of nearly similar size (optimal). Crab individuals showed a significant preference for optimal sized shells when given suboptimal shells as an alternative choice. Also, the hermit crabs avoid damaged shells when given a choice of optimal sized damaged shell and optimal sized intact one. In addition, two hermit crab species chose shells of smaller than optimal size when given a choice of damaged optimal sized shells and smaller intact ones. On the other hand, field observations showed that most crab individuals lived in adequate sized shells. The present data conclude that shell selection by hermit crabs C. latens and C. signatus depends mostly on shell internal volume, shell quality and shell aperture size than other factors, because they provide a maximum protection for hermit crabs.

  12. Habitat use and food selection of small mammals near a sagebrush/crested wheatgrass interface in southeastern Idaho

    International Nuclear Information System (INIS)

    Research has been conducted on various aspects of the ecology of wildlife residing on and adjacent to the Subsurface Disposal Area (SDA) and one other low-level radioactive waste disposal site on the Idaho National Engineering Laboratory (INEL) in southeastern Idaho. Habitat use and food selection data were collected for deer mice (Peromyscus maniculatus), montane voles (Microtus montanus), Ord's kangaroo rats (Dipodomys ordii), and Townsend's ground squirrels (Spermophilus townsendii) near a sagebrush (Artemisia tridentata)/crested wheatgrass (Agropyron cristatum) interface. Significantly more captures occurred in the native sagebrush habitat than in areas planted in crested wheatgrass or in disturbed sites. Crested wheatgrass, a prolific seed producer, still accounted for over 30% of the total captures. Montane voles and Townsend's ground squirrels (during periods of aboveground activity) used the crested wheatgrass habitat throughout the summer, while deer mice and Ord's kangaroo rats exhibited heavy use after seed set

  13. Daytime habitat selection by introduced eastern cottontail Sylvilagus floridanus and native european hare Lepus europaeus in Northern Italy.

    Science.gov (United States)

    Bertolino, Sandro; Montezemolo, Nicola Cordero di; Perrone, Aurelio

    2011-06-01

    We used radiotelemetry to investigate resting sites habitat selection by introduced eastern cottontail (Sylvilagus floridanus) and native European hare (Lepus europaeus) under sympatric conditions. We tracked 24 hares and 34 cottontails in a protected area of northwestern Italy. Hares were found in different sites every week, while cottontails used the same site for two weeks, and occasionally for longer. It is supposed that this periodic nest switching reduces the risk of predation and parasitism. Hares and cottontails forms were located in different habitats and characterized by dense vegetation cover near the ground. This cover increased from winter to summer in both species, while in autumn it continued to increase in cottontails only, and decreased in hares. Cottontails selected shrubby habitats near the river, and avoided crop fields in all seasons. Hares were more adaptive in their search, using high herbs and shrubs all year round, wheat fields in spring, maize in spring and summer, and stubbles in winter. Arguably, partial niche differentiation is necessary to allow the coexistence of similar species. In our study area, hares and cottontails differentiated in the use of resting sites habitats, presumably so as not to compete in this part of their ecological niche. PMID:21627451

  14. Daytime habitat selection by introduced eastern cottontail Sylvilagus floridanus and native european hare Lepus europaeus in Northern Italy.

    Science.gov (United States)

    Bertolino, Sandro; Montezemolo, Nicola Cordero di; Perrone, Aurelio

    2011-06-01

    We used radiotelemetry to investigate resting sites habitat selection by introduced eastern cottontail (Sylvilagus floridanus) and native European hare (Lepus europaeus) under sympatric conditions. We tracked 24 hares and 34 cottontails in a protected area of northwestern Italy. Hares were found in different sites every week, while cottontails used the same site for two weeks, and occasionally for longer. It is supposed that this periodic nest switching reduces the risk of predation and parasitism. Hares and cottontails forms were located in different habitats and characterized by dense vegetation cover near the ground. This cover increased from winter to summer in both species, while in autumn it continued to increase in cottontails only, and decreased in hares. Cottontails selected shrubby habitats near the river, and avoided crop fields in all seasons. Hares were more adaptive in their search, using high herbs and shrubs all year round, wheat fields in spring, maize in spring and summer, and stubbles in winter. Arguably, partial niche differentiation is necessary to allow the coexistence of similar species. In our study area, hares and cottontails differentiated in the use of resting sites habitats, presumably so as not to compete in this part of their ecological niche.

  15. The role of habitat-selection in restricting invasive blue mussel advancement to protect native populations in San Francisco Bay

    Science.gov (United States)

    Mittal, N.; Saarman, N. P.; Pogson, G.

    2013-12-01

    Introduced species contribute to decline of biodiversity and ecosystem services. Introduced species threaten native species by increasing competition for space and resources, changing their habitat, and disrupting species interactions. Protecting native species is crucial to preserving ecosystem services (i.e. medicinal, agricultural, ecological, and cultural benefits) for future generations. In marine communities, the number of invasive species is dramatically increasing every year, further magnifying the negative impact on native species. This research determines if habitat-specific selection can protect native species from their invasive relatives, and could allow targeted habitat restoration for native species to maintain high levels of biodiversity. Blue mussels provide an ideal system for studying the impact of an invasive species (Mytilus galloprovincialis) on native mussels (M. trossulus), because M. galloprovincialis is marked as one of the world's 100 worst invasive species. Hybridization between M. galloprovincialis and M. trossulus occurs wherever their distributions overlap (i.e. Japan, Puget Sound, and central California). In central California, hybrids form in a broad variety of habitats ever since M. galloprovincialis was introduced about 100 years ago. The current level of threat posed to native mussels in central California is unknown. When population growth rate of an invasive species is higher than the native within a hybrid zone, the invader's genes become more prominent in the hybrids than the native species' genes. This uneven mix of genes and decrease of pure native mussels threatens to drive M. trossulus to extinction. Therefore, it is important to research which environment fosters highest success of pure native species. We conducted a field experiment in San Francisco Bay where mussels were reared in different habitats. We then collected samples and extracted DNA from each treatment, and genotyped them by a next-generation sequencing

  16. Evaluation of Shorebird Use of Selected Refuge Habitats in the Lower Mississippi Valley

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — During August and September of 1994, a decision was made by the Jackson, MS, Field Office of the Branch of Wildlife and Habitat Management (WHM) Division of Refuges...

  17. Oxidative coupling of methane in a fluidized-bed reactor over a highly active and selective catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Mleczko, L.; Pannek, U. [Ruhr-Universitaet, Bochum (Germany). Lehrstuhl fuer Technische Chemie; Niemi, V.M.; Hiltunen, J. [NESTE OY, Porvoo (Finland). Technology Centre

    1996-01-01

    Oxidative coupling of methane to C{sub 2+} hydrocarbons over a Zr/La/Sr catalyst was investigated in an atmospheric-pressure shallow fluidized-bed reactor (i.d. = 5 cm; H{sub mf} = 1.4--3.2 cm) at temperatures between 800 and 880 C. The catalyst was mechanically and catalytically stable, but its fluidizability was limited; agglomeration and channeling occurred. The highest C{sub 2+} yield amounted to 18.0% (X{sub CH{sub 4}} = 36.5%, S{sub C{sub 2+}} = 49.4%) and 17.2% (X{sub CH{sub 4}} = 36.6%, S{sub C{sub 2+}} = 46.9%) for the diluted and undiluted feed, respectively. These yields are among the highest ones reported in the open literature for oxidative coupling of methane in fluidized beds. In the whole investigated temperature range higher selectivities and yields were obtained upon reducing partial pressures of methane and oxygen but keeping their ratio constant (p{sub CH{sub 4}}/p{sub O{sub 2}} = 2.5). An increased gas velocity or bed height resulted in a drop of C{sub 2+} selectivity.

  18. Habitat selection of two island-associated dolphin species from the south-west Indian Ocean

    Science.gov (United States)

    Condet, Manon; Dulau-Drouot, Violaine

    2016-08-01

    Identifying suitable habitats of protected species is an essential question in ecology and conservation planning. Modelling approaches have been widely used to identify environmental features that contribute to a species' ecological requirements and distribution. On Reunion Island, a fast-growing French territory located in the south-western Indian Ocean, anthropogenic impacts are mainly concentrated along the coast, representing a potential threat for Indo-Pacific bottlenose (Tursiops aduncus) and spinner (Stenella longirostris) dolphins, two resident coastal species. Beside coastal development, commercial and recreational dolphin-watching are growing, particularly along the west coast. To promote effective local management, habitat modelling was applied using presence-only data collected from 2008 to 2012 on the west coast of the island. Ecological Niche Factor Analyses were used to investigate the effect of physiographic variables on the distribution of these two dolphin species and delineate suitable habitats. It was found that the core habitat of Indo-Pacific bottlenose dolphins was mainly restricted by depth and confined to coastal waters ranging from 4.7 to 75.8 m deep. The species preferentially used soft substrates (sand and mud) and tended to be ubiquitous in terms of substrate type/color used. Foraging activities were significantly related to soft substrates. The diurnal core habitat of spinner dolphins was confined to one discrete area, on the flat portion of the insular shelf, between 45.1 m and 70.7 m of depth. Suitable habitat was mainly related to soft and light-colored substrates, with a clear avoidance of dark-colored substrates. The core habitats of both species were very restrained spatially and therefore vulnerable to human activities. The fine scale habitat mapping achieved in this study represents baseline data to conduct ad hoc impact assessment and support conservation actions.

  19. Selection based on the size of the black tie of the great tit may be reversed in urban habitats.

    Science.gov (United States)

    Senar, Juan Carlos; Conroy, Michael J; Quesada, Javier; Mateos-Gonzalez, Fernando

    2014-07-01

    A standard approach to model how selection shapes phenotypic traits is the analysis of capture-recapture data relating trait variation to survival. Divergent selection, however, has never been analyzed by the capture-recapture approach. Most reported examples of differences between urban and nonurban animals reflect behavioral plasticity rather than divergent selection. The aim of this paper was to use a capture-recapture approach to test the hypothesis that divergent selection can also drive local adaptation in urban habitats. We focused on the size of the black breast stripe (i.e., tie width) of the great tit (Parus major), a sexual ornament used in mate choice. Urban great tits display smaller tie sizes than forest birds. Because tie size is mostly genetically determined, it could potentially respond to selection. We analyzed capture/recapture data of male great tits in Barcelona city (N = 171) and in a nearby (7 km) forest (N = 324) from 1992 to 2008 using MARK. When modelling recapture rate, we found it to be strongly influenced by tie width, so that both for urban and forest habitats, birds with smaller ties were more trap-shy and more cautious than their larger tied counterparts. When modelling survival, we found that survival prospects in forest great tits increased the larger their tie width (i.e., directional positive selection), but the reverse was found for urban birds, with individuals displaying smaller ties showing higher survival (i.e., directional negative selection). As melanin-based tie size seems to be related to personality, and both are heritable, results may be explained by cautious personalities being favored in urban environments. More importantly, our results show that divergent selection can be an important mechanism in local adaptation to urban habitats and that capture-recapture is a powerful tool to test it. PMID:25077014

  20. Attractiveness of food and avoidance from contamination as conflicting stimuli to habitat selection by fish.

    Science.gov (United States)

    Araújo, Cristiano V M; Rodríguez, Elizabeth N V; Salvatierra, David; Cedeño-Macias, Luis A; Vera-Vera, Victoria C; Moreira-Santos, Matilde; Ribeiro, Rui

    2016-11-01

    Habitat selection by fish is the outcome of a choice between different stimuli. Typically, the presence of food tends to attract organisms, while contamination triggers an avoidance response to prevent toxic effects. Given that both food and contaminants are not homogeneously distributed in the environment and that food can be available in contaminated zones, a key question has been put forward in the present study: does a higher availability of food in contaminated areas interfere in the avoidance response to contaminants regardless of the contamination level? Tilapia fry (Oreochromis sp.; 2.5-3.0 cm and 0.5-0.8 g) were exposed to two different effluent samples, diluted along a free-choice, non-forced exposure system simulating a contamination gradient. Initially, avoidance to the effluents was checked during a one hour exposure. Afterwards, food was added to the system so that the availability of food increased with the increase in the level of contamination, and the avoidance response to contamination was checked during another hour. Results clearly showed a concentration-dependent avoidance response for both effluents during the first hour (i.e., with no food). However, in presence of the food, the avoidance pattern was altered: organisms were propelled to intermittently move towards contaminated areas where food availability was higher. The incursions were taken regardless of the potential risk linked to the toxic effects. In conclusion, even when the risk of toxicity was imminent, tilapia fry were more intensively stimulated by the attractiveness of the food than by repulsion to the contamination.

  1. RESEARCH ON THE INFLUENCE OF TEMPERATURE ON THE ACTIVATION OF SELECTED POROUS MNO2 BEDS

    Directory of Open Access Journals (Sweden)

    Iwona Skoczko

    2016-09-01

    Full Text Available Rising demands concerning water treatment and conservation make it necessary to search for more effective as well as cheap and ecologically safe solutions. During the filtration process quartz sand is replaced by filter materials which also have a strong effect on account of reactions taking place on a bed’s surface. Today’s technologies for groundwater and seepage water treatment in rapid filters make use of oxidation beds. They are able to effectively remove manganese (II and iron (II compounds based on heterogeneous oxidation catalysis. The main catalyst of the manganese removal process in terms of its catalytic oxidation in filtration beds is manganese dioxide. This compound is used as an oxidizing agent in many processes. The research conducted as part of this paper was aimed at creating a product with the qualities similar to a popular Greensand bed protected by patent. The authors tested washed quartz sand varying in granulation which was subject to activation in 10% KMnO4 solution. Grains of quartz sand after covering them with a permanent coat of manganese oxide developed the superficial oxidation layer. While performing the tests, a temperature of the process served as a variable. The beds produced as a result of the experiment enable the removal of iron and manganese from water without prior alkylation. Furthermore, they are an effective method of purifying water of organic pollutants and ammoniacal nitrogen. They function as oxidizing and filtering masses.

  2. Effects of predation risk on habitat selection by water column fish, benthic fish and crayfish in stream pools

    Science.gov (United States)

    Magoulick, D.D.

    2004-01-01

    Predation risk can affect habitat selection by water column stream fish and crayfish, but little is known regarding effects of predation risk on habitat selection by benthic fish or assemblages of fish and crayfish. I used comparative studies and manipulative field experiments to determine whether, (1) habitat selection by stream fish and crayfish is affected by predation risk, and (2) benthic fish, water column fish, and crayfish differ in their habitat selection and response to predation risk. Snorkeling was used to observe fish and crayfish in, (1) unmanipulated stream pools with and without large smallmouth bass predators (Micropterus dolomieui >200 mm total length, TL) and (2) manipulated stream pools before and after addition of a single large smallmouth bass, to determine if prey size and presence of large fish predators affected habitat selection. Observations of microhabitat use were compared with microhabitat availability to determine microhabitat selection. Small fish (60-100 mm TL, except darters that were 30-100 mm TL) and crayfish (40-100 mm rostrum to telson length; TL) had significantly reduced densities in pools with large bass, whereas densities of large fish and crayfish (> 100 mm TL) did not differ significantly between pools with and without large bass. Small orangethroat darters (Etheostoma spectabile), northern crayfish (Orconectes virilis), and creek chubs (Semotilus atromaculatus) showed significantly greater densities in pools without large bass. The presence of large smallmouth bass did not significantly affect depths selected by fish and crayfish, except minnows, which were found significantly more often at medium depths when bass were present. Small minnows and large and small crayfish showed the greatest response to additions of bass to stream pools by moving away from bass locations and into shallow water. Small darters and sunfish showed an intermediate response, whereas large minnows showed no significant response to bass additions

  3. Habitat selection of breeding brown eared-pheasants (Crossoptilon mantchuricum) in Xiaowutaishan National Nature Reserve,Hebei Province,China

    Institute of Scientific and Technical Information of China (English)

    Dongming LI; Shiping GAO; Yuefeng WU; Lihan SUN; Shubin GUO; Jili LI

    2009-01-01

    From April to July of 2003-2005,we investigated habitat selection of breeding brown eared-pheasants (Crossoptilon mantchuricum) in the Xiaowutaishan National Nature Reserve,Hebei Province.Our results show that brown eared-pheasants preferred deciduousconiferous mixed or deciduous forests with altitudes ranging from 1600 to 2200 m,steep gradients of slopes and medium or high positions on slopes.Moreover,they preferred habitats with more tree species,larger diameters at the breast height,more density and cover of trees and habitats with more types of grasses,high density and cover of grasses,but with fewer types of shrubs and lower density and cover of shrubs.They had larger territories in the early breeding stage than in the late breeding stage.There were significant differences in diameters at the breast height of trees,average height of trees,cover of trees,density of shrubs,cover of shrubs,aspect,distance to path,distance to water,distance to forest edge (P < 0.01,respectively),density of trees,type of shrubs,height of shrubs,type of grasses,density of grasses and proportion of bareness (P < 0.05,respectively).The result of the principal component analysis suggested that the principal components among the 23 habitat factors were the average height of trees,density of trees,diameters at the breast height of trees,density of shrubs,cover of shrubs and density of grasses.The differences in habitat selection of brown eared-pheasants between early breeding and late breeding stages may correlate with the dynamics of ambient environmental conditions,the reproductive behavior and energy requirements in their sub-stages of breeding.

  4. Spatial Niche Segregation of Sympatric Stone Marten and Pine Marten--Avoidance of Competition or Selection of Optimal Habitat?

    Directory of Open Access Journals (Sweden)

    Anna Wereszczuk

    Full Text Available Coexistence of ecologically similar species relies on differences in one or more dimensions of their ecological niches, such as space, time and resources in diel and/or seasonal scales. However, niche differentiation may result from other mechanisms such as avoidance of high predation pressure, different adaptations or requirements of ecologically similar species. Stone marten (Martes foina and pine marten (Martes martes occur sympatrically over a large area in Central Europe and utilize similar habitats and food, therefore it is expected that their coexistence requires differentiation in at least one of their niche dimensions or the mechanisms through which these dimensions are used. To test this hypothesis, we used differences in the species activity patterns and habitat selection, estimated with a resource selection function (RSF, to predict the relative probability of occurrence of the two species within a large forest complex in the northern geographic range of the stone marten. Stone martens were significantly heavier, have a longer body and a better body condition than pine martens. We found weak evidence for temporal niche segregation between the species. Stone and pine martens were both primarily nocturnal, but pine martens were active more frequently during the day and significantly reduced the duration of activity during autumn-winter. Stone and pine martens utilized different habitats and almost completely separated their habitat niches. Stone marten strongly preferred developed areas and avoided meadows and coniferous or deciduous forests. Pine marten preferred deciduous forest and small patches covered by trees, and avoided developed areas and meadows. We conclude that complete habitat segregation of the two marten species facilitates sympatric coexistence in this area. However, spatial niche segregation between these species was more likely due to differences in adaptation to cold climate, avoidance of high predator pressure and

  5. Spatial Niche Segregation of Sympatric Stone Marten and Pine Marten--Avoidance of Competition or Selection of Optimal Habitat?

    Science.gov (United States)

    Wereszczuk, Anna; Zalewski, Andrzej

    2015-01-01

    Coexistence of ecologically similar species relies on differences in one or more dimensions of their ecological niches, such as space, time and resources in diel and/or seasonal scales. However, niche differentiation may result from other mechanisms such as avoidance of high predation pressure, different adaptations or requirements of ecologically similar species. Stone marten (Martes foina) and pine marten (Martes martes) occur sympatrically over a large area in Central Europe and utilize similar habitats and food, therefore it is expected that their coexistence requires differentiation in at least one of their niche dimensions or the mechanisms through which these dimensions are used. To test this hypothesis, we used differences in the species activity patterns and habitat selection, estimated with a resource selection function (RSF), to predict the relative probability of occurrence of the two species within a large forest complex in the northern geographic range of the stone marten. Stone martens were significantly heavier, have a longer body and a better body condition than pine martens. We found weak evidence for temporal niche segregation between the species. Stone and pine martens were both primarily nocturnal, but pine martens were active more frequently during the day and significantly reduced the duration of activity during autumn-winter. Stone and pine martens utilized different habitats and almost completely separated their habitat niches. Stone marten strongly preferred developed areas and avoided meadows and coniferous or deciduous forests. Pine marten preferred deciduous forest and small patches covered by trees, and avoided developed areas and meadows. We conclude that complete habitat segregation of the two marten species facilitates sympatric coexistence in this area. However, spatial niche segregation between these species was more likely due to differences in adaptation to cold climate, avoidance of high predator pressure and/or food

  6. Vegetation biomass and habitat selection by a newly introduced population of muskoxen in northern Quebec

    Directory of Open Access Journals (Sweden)

    René Nault

    1993-12-01

    Full Text Available Ground coverage by woody and herbaceous plant species and standing biomass of vegetation susceptible to being grazed upon were estimated in a 156 km2 area where 190 muskoxen were censused during the preceding autumn. Habitat use was estimated with droppings census. Six terrestrial habitat types were delineated on 1:32 000 aerial photographs and randomly sampled: low shrub on xeric sites (LSX; 64 km2, low shrub on mesic sites (LSM; 45 km2, bare ground (BG; 27 km2, forest-tundra (FT; 12 km2, wet meadow (WM; 2 km2 and riparian willows (RW; 1 km2. Dominant plant species varied greatly between habitat types, and only a few such as Betula glandulosa, Salix arctophila, and Polygonum viviparum were common. Tall shrubs were present only in RW where they covered most of the ground, and in FT. Low shrubs were uniformly distributed and covered 18-32% of the ground, with the exception of RW (5%. Ground cover by herbs had a similar range (i.e. 20-37%, except in RW where the mean exceeded 50%. Mosses and lichens occupied about half of the ground everywhere. Phytomass exhibited great variation within and between habitat types; extreme values averaged 892 kg*ha-1 in LSX, and 1965 kg*ha-1 in LSM. However the difference was not significant due to limited sample size and within habitat variance. Nevertheless the mass of herbaceous dicots was greater in RW than in any other habitat type. Total phytomass was 2-20 times greater in northern Québec than in Greenland. Based on droppings density, muskoxen preferred RW over BG and FT, and LSX over BG. Although the density of muskoxen in the study area was high relative to other muskox ranges, habitat quality and quantity should allow continued population growth.

  7. Oligotyping reveals community level habitat selection within the genus Vibrio

    Directory of Open Access Journals (Sweden)

    Victor Thomas Schmidt

    2014-11-01

    Full Text Available The genus Vibrio is a metabolically and genetically diverse group of facultative anaerobic Bacteria, common in aquatic environments and marine hosts. The genus contains several species of importance to human health and aquaculture, including the causative agents of human cholera and fish vibriosis. Vibrios display a wide variety of known life histories, from opportunistic pathogens to long-standing symbioses with individual host species. Studying Vibrio ecology has been challenging as individual species often display a wide range of habitat preferences, and groups of vibrios can act as socially cohesive groups. Although strong associations with salinity, temperature and other environmental variables have been established, the degree of habitat or host specificity at both the individual and community levels is unknown. Here we use oligotyping analyses in combination with a large collection of existing Vibrio 16S ribosomal RNA (rRNA gene sequence data to reveal patterns of Vibrio ecology across a wide range of environmental, host, and abiotic substrate associated habitats. Our data show that individual taxa often display a wide range of habitat preferences yet tend to be highly abundant in either substrate-associated or free-living environments. Our analyses show that Vibrio communities share considerable overlap between two distinct hosts (i.e., sponge and fish yet are distinct from the abiotic plastic substrates. Lastly, evidence for habitat specificity at the community level exists in some habitats, despite considerable stochasticity in others. In addition to providing insights into Vibrio ecology across a broad range of habitats, our study shows the utility of oligotyping as a facile, high-throughput and unbiased method for large scale analyses of publicly available sequence data repositories and suggests its wide application could greatly extend the range of possibilities to explore microbial ecology.

  8. Evaluation of Macroinvertebrate Communities and Habitat for Selected Stream Reaches at Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    L.J. Henne; K.J. Buckley

    2005-08-12

    This is the second aquatic biological monitoring report generated by Los Alamos National Laboratory's (LANL's) Water Quality and Hydrology Group. The study has been conducted to generate impact-based assessments of habitat and water quality for LANL waterways. The monitoring program was designed to allow for the detection of spatial and temporal trends in water and habitat quality through ongoing, biannual monitoring of habitat characteristics and benthic aquatic macroinvertebrate communities at six key sites in Los Alamos, Sandia, Water, Pajarito, and Starmer's Gulch Canyons. Data were collected on aquatic habitat characteristics, channel substrate, and macroinvertebrate communities during 2001 and 2002. Aquatic habitat scores were stable between 2001 and 2002 at all locations except Starmer's Gulch and Pajarito Canyon, which had lower scores in 2002 due to low flow conditions. Channel substrate changes were most evident at the upper Los Alamos and Pajarito study reaches. The macroinvertebrate Stream Condition Index (SCI) indicated moderate to severe impairment at upper Los Alamos Canyon, slight to moderate impairment at upper Sandia Canyon, and little or no impairment at lower Sandia Canyon, Starmer's Gulch, and Pajarito Canyon. Habitat, substrate, and macroinvertebrate data from the site in upper Los Alamos Canyon indicated severe impacts from the Cerro Grande Fire of 2000. Impairment in the macroinvertebrate community at upper Sandia Canyon was probably due to effluent-dominated flow at that site. The minimal impairment SCI scores for the lower Sandia site indicated that water quality improved with distance downstream from the outfall at upper Sandia Canyon.

  9. Among-habitat algal selectivity by browsing herbivores on an inshore coral reef

    Science.gov (United States)

    Loffler, Zoe; Bellwood, David R.; Hoey, Andrew S.

    2015-06-01

    Understanding how the impact of different herbivores varies spatially on coral reefs is important in qualifying the resistance of coral reefs to disturbance events and identifying the processes that structure algal communities. We used assays of six common macroalgae ( Acanthophora spicifera, Caulerpa taxifolia, Galaxaura rugosa, Laurencia sp. Sargassum sp., and Turbinaria ornata) and remote underwater video cameras to quantify herbivory in two habitats (reef crest and slope) across multiple sites on Orpheus Island, Great Barrier Reef. Rates of herbivory varied among macroalgal taxa, habitats, and sites. Reductions in algal biomass were greatest for Sargassum sp. (36 % 4 h-1), intermediate for A. spicifera, Laurencia sp., C. taxifolia, and T. ornata (17-33 % 4 h-1) and lowest for G. rugosa (6 % 4 h-1). Overall, rates of herbivory were generally greater on the reef crest (30 % 4 h-1) than the reef slope (21 % 4 h-1). This difference in rates of herbivory coincided with a marked shift in the dominant herbivores between habitats. Kyphosus vaigiensis, despite only feeding on three species of macroalgae ( Sargassum sp., T. ornata, and A. spicifera), was responsible for 34 % of all bites recorded on the reef crest yet did not take a single bite from algae on the reef slope. In contrast, Siganus doliatus took bites on every species of algae in both habitats, accounting for 40 % of bites on the reef crest and 74 % of all bites recorded on the reef slope. This difference in the number of macroalgal species targeted by herbivores and the habitat/s in which they feed adds another dimension of complexity to our understanding of coral reef herbivore dynamics.

  10. Habitat selection by anurofauna community at rocky seashore in coastal Atlantic Forest, Southeastern Brazil.

    Science.gov (United States)

    Pontes, R C; Santori, R T; Gonçalves e Cunha, F C; Pontes, J A L

    2013-08-01

    Rocky seashores are low granitic hills distributed along the southeastern Brazilian coast with xeric-like vegetation due to the shallow soil. Knowledge on amphibian communities and their reproductive patterns is especially reduced on this kind of environment. Herein, we present a framework of two years monitoring an amphibian community at a rocky seashore environment located at the protected area of Parque Estadual da Serra da Tiririca, municipality of Niterói, state of Rio de Janeiro, Brazil. We conducted diurnal and nocturnal searches for frogs in tank bromeliads, rocky surface and shrubby vegetation. Annual pattern of breeding activity of anurans was also estimated. Individuals of the most abundant tank-bromeliad, Alcantarea glaziouana were collected and measured according to several variables to understanding the selection of bromeliads by frogs. We checked the influence of the environmental conditions on amphibian abundance, association between the bromeliads measures, and the water storage in the tank. We recorded the species: Scinax aff. x-signatus; S. cuspidatus; S. littoreus; Thoropa miliaris and Gastrotheca sp. Bromeliads were the preferential habitat used by anurans. The nocturnal habit was predominant for all species and during diurnal searches, the specimens were found sheltered in bromeliads axils. The number of calling males as well as amphibian abundance was associated with the rainiest and warmest period of the year. The species S. littoreus was observed in breeding activity in the majority of sample period. Adult calling males of T. miliaris were observed especially in the rainy season. Rainfall and temperature combined are positively correlated to the total number of captured amphibians. However, individually, rainfall was not significantly correlated, while temperature was positively correlated with the amphibian abundance. Water storage capacity by bromeliads was correlated to characteristics and size of the plant. In the rainy season, the

  11. Risk spreading, habitat selection and division of biomass in a submerged clonal plant: Responses to heterogeneous copper pollution

    International Nuclear Information System (INIS)

    Heterogeneity of contaminant-stress can be an important environmental factor for clonal plants. We focused on Cu transport among the clones, the foraging or fugitive behavior and biomass allocation of submerged plant, Vallisneria natans (Lour.) Hara, exposed to heterogeneous sediments. This study was carried out in aquatic mesocosms between March and September 2010. Cu accumulated in contaminated ramets was exported horizontally via stolons to other ramets in uncontaminated patches, and then transported both acropetally to leaves and basipetally to belowground structures. There was no indication that V. natans adopted morphological plasticity in response to heterogeneous contaminated habitat. In contrast to predictions, more biomass was allocated to belowground tissues in contaminated patches. We concluded that risk of Cu stress spread among submerged clones, and V. natans did not actively select habitat in contaminated patchy environment. Furthermore, V. natans adopted compensatory investments instead of division of labor to acquire nutrient and survive. -- Highlights: ► Response of submerged clonal plant in heterogeneous Cu soil was studied. ► Cu can spread among V. natans clones in contaminated patches. ► Ramets of V. natans grow randomly instead of habitat selection actively. ► Individual growth in patchy pollution was relative independent rather than DoL. -- Cu can spread among V. natans clones and the clones grow randomly and relative independent in heterogeneous Cu-contaminated sediment

  12. Predicting and Mapping Potential Whooping Crane Stopover Habitat to Guide Site Selection for Wind Energy Projects

    Science.gov (United States)

    Migration is one of the most poorly understood components of a bird’s life cycle. For that reason, migratory stopover habitats are often not part of conservation planning and may be overlooked when planning new development projects. This project highlights and addresses an overl...

  13. Habitat selection of a parasitoid mediated by volatiles informing on host and intraguild predator densities

    DEFF Research Database (Denmark)

    Cotes, Belén; Rännbäck, Linda Marie; Björkman, Maria;

    2015-01-01

    both a parasitoid and its host, parasitoids may reduce the risk of intraguild predation (IGP) by avoiding such patches. In this study, we examined whether the presence of the entomopathogenic fungi Metarhizium brunneum and Beauveria bassiana in soil habitats of a root herbivore, Delia radicum, affects...

  14. Habitat selection of two sympatric species of Ameiva in East Costa Rica

    Directory of Open Access Journals (Sweden)

    Esther Sebastián-González

    2012-12-01

    Full Text Available Identifying the differences in habitat use for sympatric species is important for understanding the species preferences and the limits of population distribution. We studied the differences in the habitat use of two understudied sympatric species of Ameiva (A. festiva and A. quadrilineata in a natural reserve of the Caribbean coast of Coast Rica. Ameiva quadrilineata showed a more restrictive habitat use pattern than A. festiva. A. quadrilineata’s smaller body size may be one of the factors limiting its habitat range. Both species showed higher density in regenerated forests, while A. quadrilineata was never found in swamp forests. The air temperature and the meteorological condition at the moment of the survey also influenced the occurrence of the A. quadrilineata, while the juveniles of A. festiva were only affected by the meteorological condition. None of the studied variables seemed to affect the occurrence of A. festiva adults. The results of this study can be useful to evaluate possible changes in the species distribution patterns as a consequence of direct (i.e., deforestation or indirect (i.e., climate change human activities in the distribution area of these species.

  15. A freshwater species wintering in a brackish environment: Habitat selection and diet of Slavonian grebes in the southern Baltic Sea

    Science.gov (United States)

    Sonntag, Nicole; Garthe, Stefan; Adler, Sven

    2009-09-01

    After the breeding season, Slavonian grebes ( Podiceps auritus) leave their freshwater breeding habitats and migrate to wintering grounds in marine or brackish waters. The most important wintering area in northwestern Europe is located in the southern Baltic Sea, with the largest concentrations in the offshore area of the Pommeranian Bight. Analysis of ship-based surveys revealed that the habitat selection of Slavonian grebes in this brackish area is significantly influenced by water depth and bottom sediment type. The grebes prefer shallow waters of 4-14 m depth and occur only over sandy sediments. While the diving depths of endothermic animals is limited due to energetic constraints and thermoregulation, sediment type is regarded to be a proxy for food choice. The diet of Slavonian grebes in the Pomeranian Bight consists mainly of demersal gobies (Gobiidae) that frequently occur over sandy bottom substrates.

  16. LiDAR Remote Sensing of Forest Structure and GPS Telemetry Data Provide Insights on Winter Habitat Selection of European Roe Deer

    Directory of Open Access Journals (Sweden)

    Michael Ewald

    2014-06-01

    Full Text Available The combination of GPS-Telemetry and resource selection functions is widely used to analyze animal habitat selection. Rapid large-scale assessment of vegetation structure allows bridging the requirements of habitat selection studies on grain size and extent, particularly in forest habitats. For roe deer, the cold period in winter forces individuals to optimize their trade off in searching for food and shelter. We analyzed the winter habitat selection of roe deer (Capreolus capreolus in a montane forest landscape combining estimates of vegetation cover in three different height strata, derived from high resolution airborne Laser-scanning (LiDAR, Light detection and ranging, and activity data from GPS telemetry. Specifically, we tested the influence of temperature, snow height, and wind speed on site selection, differentiating between active and resting animals using mixed-effects conditional logistic regression models in a case-control design. Site selection was best explained by temperature deviations from hourly means, snow height, and activity status of the animals. Roe deer tended to use forests of high canopy cover more frequently with decreasing temperature, and when snow height exceeded 0.6 m. Active animals preferred lower canopy cover, but higher understory cover. Our approach demonstrates the potential of LiDAR measures for studying fine scale habitat selection in complex three-dimensional habitats, such as forests.

  17. Efficacy of Selected Insecticide Sprays and Aerosols against the Common Bed Bug, Cimex lectularius (Hemiptera: Cimicidae

    Directory of Open Access Journals (Sweden)

    Changlu Wang

    2016-01-01

    Full Text Available We evaluated the residual efficacy of four liquid sprays and four ready-to-use aerosols that are commonly used in the U.S. against a field-collected bed bug, Cimex lectularius L., strain with moderate resistance level to pyrethroids. The four liquid sprays were: Tandem (0.1% thiamethoxam, 0.03% lambda-cyhalothrin, Temprid SC (0.05% imidacloprid, 0.025% cyfluthrin, Transport GHP (0.05% acetamiprid, 0.06% bifenthrin, and Demand CS (0.03% lambda-cyhalothrin. The four aerosols were: Alpine (0.5% dinotefuran, Bedlam (0.4% sumithrin, 1.6% MGK 264, Bedlam Plus (0.4% sumithrin, 1% MGK 264, 0.05% imidacloprid, and Phantom (0.5% chlorfenapyr. Bed bugs were confined for 4 h to treated substrates (aged 24 h. Four substrates were tested: fabric, unpainted wood, painted wood, and vinyl. Bedlam, Demand CS, and Temprid SC resulted in ≤70% mortality on all tested substrates. Among the other five products, substrate type significantly affected their residual efficacy, except for Transport GHP, which caused ≥89.7% mortality regardless of the substrate. The effect of exposure time (5 min, 4 h, and 24 h on the efficacy of Transport GHP and Phantom aerosol also was evaluated. A 4 h continuous exposure to Phantom aerosol or Transport GHP residue caused similar mortality to 24 h exposure and higher mortality than 5 min exposure.

  18. Efficacy of Selected Insecticide Sprays and Aerosols against the Common Bed Bug, Cimex lectularius (Hemiptera: Cimicidae).

    Science.gov (United States)

    Wang, Changlu; Singh, Narinderpal; Zha, Chen; Cooper, Richard

    2016-01-01

    We evaluated the residual efficacy of four liquid sprays and four ready-to-use aerosols that are commonly used in the U.S. against a field-collected bed bug, Cimex lectularius L., strain with moderate resistance level to pyrethroids. The four liquid sprays were: Tandem (0.1% thiamethoxam, 0.03% lambda-cyhalothrin), Temprid SC (0.05% imidacloprid, 0.025% cyfluthrin), Transport GHP (0.05% acetamiprid, 0.06% bifenthrin), and Demand CS (0.03% lambda-cyhalothrin). The four aerosols were: Alpine (0.5% dinotefuran), Bedlam (0.4% sumithrin, 1.6% MGK 264), Bedlam Plus (0.4% sumithrin, 1% MGK 264, 0.05% imidacloprid), and Phantom (0.5% chlorfenapyr). Bed bugs were confined for 4 h to treated substrates (aged 24 h). Four substrates were tested: fabric, unpainted wood, painted wood, and vinyl. Bedlam, Demand CS, and Temprid SC resulted in ≤70% mortality on all tested substrates. Among the other five products, substrate type significantly affected their residual efficacy, except for Transport GHP, which caused ≥89.7% mortality regardless of the substrate. The effect of exposure time (5 min, 4 h, and 24 h) on the efficacy of Transport GHP and Phantom aerosol also was evaluated. A 4 h continuous exposure to Phantom aerosol or Transport GHP residue caused similar mortality to 24 h exposure and higher mortality than 5 min exposure. PMID:26840334

  19. Abiotic vs. biotic influences on habitat selection of coexisting species: Climate change impacts?

    Science.gov (United States)

    Martin, T.E.

    2001-01-01

    Species are commonly segregated along gradients of microclimate and vegetation. I explore the question of whether segregation is the result of microhabitat partitioning (biotic effects) or choice of differing microclimates (abiotic effects). I explored this question for four ground-nesting bird species that are segregated along a microclimate and vegetation gradient in Arizona. Birds shifted position of their nests on the microhabitat and microclimate gradient in response to changing precipitation over nine years. Similarly, annual bird abundance varied with precipitation across 12 yr. Those shifts in abundance and nesting microhabitat with changing precipitation demonstrate the importance of abiotic influences on bird distributions and habitat choice. However, nest-site shifts and microhabitat use also appear to be influenced by interactions among coexisting species. Moreover, shifts in habitat use by all species caused nest predation (i.e., biotic) costs that increased with increasing distance along the microclimate gradient. These results indicate that abiotic and biotic costs can strongly interact to influence microhabitat choice and abundances of coexisting species. Global climate change impacts have been considered largely in terms of simple distributional shifts, but these results indicate that shifts can also increase biotic costs when species move into habitat types for which they are poorly adapted or that create new biotic interactions.

  20. Habitat selection by green turtles in a spatially heterogeneous benthic landscape in Dry Tortugas National Park, Florida

    Science.gov (United States)

    Fujisaki, Ikuko; Hart, Kristen M.; Sartain-Iverson, Autumn R.

    2016-01-01

    We examined habitat selection by green turtles Chelonia mydas at Dry Tortugas National Park, Florida, USA. We tracked 15 turtles (6 females and 9 males) using platform transmitter terminals (PTTs); 13 of these turtles were equipped with additional acoustic transmitters. Location data by PTTs comprised periods of 40 to 226 d in varying months from 2009 to 2012. Core areas were concentrated in shallow water (mean bathymetry depth of 7.7 m) with a comparably dense coverage of seagrass; however, the utilization distribution overlap index indicated a low degree of habitat sharing. The probability of detecting a turtle on an acoustic receiver was inversely associated with the distance from the receiver to turtle capture sites and was lower in shallower water. The estimated daily detection probability of a single turtle at a given acoustic station throughout the acoustic array was small (<0.1 in any year), and that of multiple turtle detections was even smaller. However, the conditional probability of multiple turtle detections, given at least one turtle detection at a receiver, was much higher despite the small number of tagged turtles in each year (n = 1 to 5). Also, multiple detections of different turtles at a receiver frequently occurred within a few minutes (40%, or 164 of 415, occurred within 1 min). Our numerical estimates of core area overlap, co-occupancy probabilities, and habitat characterization for green turtles could be used to guide conservation of the area to sustain the population of this species.

  1. Effect of various sources of organic carbon and high nitrite and nitrate concentrations on the selection of denitrifying bacteria. II. Continuous cultures in packed bed reactors.

    Science.gov (United States)

    Błaszczyk, M

    1983-01-01

    The effect of different organic compounds, nitrites and nitrates at the concentration of 1,000 mg N/l on the quantitative and strain-specific selection of denitrifying bacteria was determined in anaerobic packed bed reactors. Both the source of carbon and nitrogen form influenced strain specificity and the frequency of occurrence of denitrifying bacteria. The frequency of denitrifying bacteria within packed bed reactor ranged in different media from 11% (glucose and nitrates) to 100% (methanol and ethanol with nitrates). A single species selection was observed in the presence of nitrites within packed bed reactor: Pseudomonas aeruginosa in medium with acetate. Pseudomonas stutzeri in medium with ethanol, Pseudomonas mendocina in medium with methanol and Pseudomonas fluorescens in medium with glucose. When nitrates were present in packed bed reactor, the dominating bacteria were: P. stutzeri in medium with acetate, P. fluorescens in medium with ethanol, Paracoccus denitrificans in medium with methanol and Alcaligenes faecalis in medium with glucose. PMID:6194668

  2. Chernobyl cesium in the Swedish moose population: Effect of age, diet and habitat selection

    International Nuclear Information System (INIS)

    The most important game in Sweden is moose (Alces alces (L.)). To study the 137Cs levels in moose, hunters were asked to send in moose meat for analysis. About 6500 samples were analysed from 1986-1993. There was a positive correlation between the fall-out of cesium from Chernobyl and the cesium concentration in moose. The differences in 137Cs concentration between moose of the same age and sex, results from individual moose consuming plants of different 137Cs concentrations, due to the use of different habitat types. The differences in 137Cs levels between years probably depends on between-year variation in habitat utilization due to the weather. During warm summers and autumns, moose utilize more wetlands (cool habitats during warm days) or mature forests (which are shady during sunny days) and consume the plants (of high 137Cs levels) found there, whereby their meat will have a higher 137Cs concentration. If, during colder summers, moose instead use farmlands or clear-cut forest areas and consume the plants (of low 137Cs levels) found there, a lower 137Cs concentration will be the case. The 137Cs concentration in moose also fluctuates seasonally depending on diet, i.e. there are high average concentrations and large differences between individual moose killed during the plant growing season, but low 137Cs concentrations and low variation between individuals and years, for moose killed during the winter. The analyses of 137Cs in moose and its food plants from before and after the Chernobyl accident indicates that the 137Cs from Chernobyl will stay in the northern forest ecosystem for a long time. The physical decay (30.2 years) seems to be the major factor for its disappearance from the ecosystem. I also expect that the fluctuation between years in the 137Cs concentration will persist, although decrease in maximum values. 44 refs, 7 figs

  3. 鸟类夜栖地选择研究进展%Roost habitat selection by birds: A review

    Institute of Scientific and Technical Information of China (English)

    原宝东; 蒋爱伍; 李晓东; 鲁长虎

    2012-01-01

    Roost habitat can provide safe, warm, and comfortable site for birds rest at night. Because of the poor night vision capability, daytime-activity birds are difficult to perceive the potential threat of roosting environment, which make their roosting in a dangerous ambience. By choosing appropriate roosting sites, birds can take full advantage of roosting space resources. From the aspects of behavior adaptability in roost habitat selection and related affecting factors (temperature, food, and safety) , this paper reviewed the researches on the roost habitat selection by birds, aimed to provide some useful ideas for the future study.%夜栖地可以为鸟类提供安全、舒适、温暖的夜间栖息场所.昼行性鸟类夜间视觉能力较差,对夜栖环境中潜在的威胁感知程度较低,导致其夜栖时常常处于被动和危险的环境中.鸟类通过选择适宜的夜栖地,进而达到充分利用夜栖地空间资源的目的.本文从鸟类夜栖地选择的行为适应性以及保温性、食物因子和安全性(隐蔽性)等3个影响因素,对国内外鸟类夜栖地选择相关研究进行综述,为今后该领域的研究提供更多思路.

  4. Selective adhesion of wastewater bacteria to Pleurotus ostreatus mycelium in a trickle-bed bioreactor

    Directory of Open Access Journals (Sweden)

    Čeněk Novotný

    2016-07-01

    Full Text Available The work is focused on spontaneous colonization of fungal mycelium by invading microorganisms in a trickle-bed fungal bioreactor operating under semi-sterile conditions. Pleurotus ostreatus was grown under the flow of synthetic wastewater containing activated sludge bacteria and the microbial consortium developed in the reactor was characterized. Genotype and phenotype profile of the reactor-invading, bacterial consortium was clearly distinctive from that of the original activated sludge. The bacterial consortium from the reactor contained a higher portion of bacteria capable of cellobiose utilization and a small amount of bacteria with the ability to utilize benzoic acids. The invading bacteria had no effect on the dye decolorization performance of the fungal reactor. Five bacterial strains colonizing P. ostreatus reactor cultures were isolated and identified as species of the genera Pseudomonas and Bacillus. Except for Bacillus cereus all strains displayed a potential to inhibit fungal growth on solid media (14 to 51 % inhibition which was comparable or higher than that of the reference bacterial strains. The pH- and media composition-dependence of the growth inhibition was demonstrated.

  5. Fingerprints of environmental stressors in three selected Slovenian gravel-bed rivers: geochemical and isotopic approach

    Science.gov (United States)

    Kanduč, Tjaša; Kocman, David; Debeljak, Barbara; Mori, Nataša

    2016-04-01

    Rivers are severely impacted by a range of simultaneous processes including water pollution, flow and channel alteration, over-fishing, invasive species and climate change. Systematic studies of river water geochemistry provide important information on chemical weathering of bedrock/soil and natural anthropogenic processes that may control the dissolved chemical loads, while the isotopic studies of biological components of river systems (macrophytes, periphyton, heterotrophic biofilm, invertebrates, fish) contribute to the understanding how the system response to human impacts by means of functional response. In this contribution, insights in the fingerprints of various environmental stressors in three gravel-bed rivers (River Kamni\\vska Bistrica, River Idrijca and River Sava) in Slovenia, using geochemical and stable isotope approach are discussed. Gravel bed of all three rivers investigated is composed of carbonates and clastic rocks. The Sava and Kamni\\vska Bistrica Rivers have alpine high mountain snow-rain regime. The Idrijca River is a boundary river between the Adriatic and Black Sea catchments and has rain-snow discharge regime with torrential character. Geochemical methods (ICP-OES, IC, total alkalinity after Gran) and isotope mass - spectrometric methods (isotopic composition of dissolved inorganic carbon, particulate organic carbon and isotopic composition of carbon in carbonates) were used to evaluate biogeochemical processes in rivers. Isotopic composition of carbon and nitrogen of the moss Fontinalis antipyretica (the whole vegetative shoot) and isotopic composition of carbon of heterotrophic biofilm was also analyzed in order to better understand the fluxes and fractionation of carbon and nitrogen across trophic levels. Geochemical composition of all investigated rivers is HCO3--Ca2+-Mg2+ with different Mg2+/Ca2+ ratios as follows: around 0.33 for Kamni\\vska Bistrica and River Sava in Slovenia and above 0.75 for River Idrijca. In the Kamni

  6. Summer resource selection and identification of important habitat prior to industrial development for the Teshekpuk Caribou Herd in northern Alaska.

    Directory of Open Access Journals (Sweden)

    Ryan R Wilson

    Full Text Available Many caribou (Rangifer tarandus populations are declining worldwide in part due to disturbance from human development. Prior to human development, important areas of habitat should be identified to help managers minimize adverse effects. Resource selection functions can help identify these areas by providing a link between space use and landscape attributes. We estimated resource selection during five summer periods at two spatial scales for the Teshekpuk Caribou Herd in northern Alaska prior to industrial development to identify areas of high predicted use for the herd. Additionally, given the strong influence parturition and insect harassment have on space use, we determined how selection differed between parturient and non-parturient females, and between periods with and without insect harassment. We used location data acquired between 2004-2010 for 41 female caribou to estimate resource selection functions. Patterns of selection varied through summer but caribou consistently avoided patches of flooded vegetation and selected areas with a high density of sedge-grass meadow. Predicted use by parturient females during calving was almost entirely restricted to the area surrounding Teshekpuk Lake presumably due to high concentration of sedge-grass meadows, whereas selection for this area by non-parturient females was less strong. When insect harassment was low, caribou primarily selected the areas around Teshekpuk Lake but when it was high, caribou used areas having climates where insect abundance would be lower (i.e., coastal margins, gravel bars. Areas with a high probability of use were predominately restricted to the area surrounding Teshekpuk Lake except during late summer when high use areas were less aggregated because of more general patterns of resource selection. Planning is currently underway for establishing where oil and gas development can occur in the herd's range, so our results provide land managers with information that can help

  7. Diversity patterns of selected Andean plant groups correspond to topography and habitat dynamics, not orogeny

    Directory of Open Access Journals (Sweden)

    Jens eMutke

    2014-10-01

    Full Text Available The tropical Andes are a hotspot of biodiversity, but detailed altitudinal and latitudinal distribution patterns of species are poorly understood. We compare the distribution and diversity patterns of four Andean plant groups on the basis of georeferenced specimen data: the genus Nasa (Loasaceae, the two South American sections of Ribes (sect. Parilla and sect. Andina, Grossulariaceae, and the American clade of Urtica (Urticaceae. In the tropical Andes, these often grow together, especially in (naturally or anthropogenically disturbed or secondary vegetation at middle to upper elevations. The climatic niches of the tropical groups studied here are relatively similar in temperature and temperature seasonality, but do differ in moisture seasonality. The Amotape-Huancabamba Zone (AHZ between 3–8° S shows a clear diversity peak of overall species richness as well as for narrowly endemic species across the groups studied. For Nasa, we also show a particular diversity of growth forms in the AHZ. This can be interpreted as proxy for a high diversity of ecological niches based on high spatial habitat heterogeneity in this zone. Latitudinal ranges are generally larger towards the margins of overall range of the group. Species number and number of endemic species of our taxa peak at elevations of 2,500–3,500 m in the tropical Andes. Altitudinal diversity patterns correspond well with the altitudinal distribution of slope inclination. We hypothesize that the likelihood and frequency of landslides at steeper slopes translates into temporal habitat heterogeneity. The frequency of landslides may be causally connected to diversification especially for the numerous early colonizing taxa, such as Urtica and annual species of Nasa. In contrast to earlier hypotheses, uplift history is not reflected in the pattern here retrieved, since the AHZ is the area of the most recent Andean uplift. Similarly, a barrier effect of the low-lying Huancabamba depression is

  8. Consequences of scale of flow field observation on apparent energy expenditure and habitat selection by juvenile coho

    Science.gov (United States)

    Tullos, D. D.; Walter, C.; Dunham, J.

    2015-12-01

    We conducted a 1:1 scale model of a full-channel log jam in an outdoor experimental channel with the objectives of 1) evaluating how the magnitude and variability of velocity changes with increasing discretization of the flow field; 2) demonstrating how velocities at different resolutions impact perceived selection of fish habitat; 3) documenting how energy expenditure estimated from velocity measured at different scales (indirect method) corresponds to estimates based on tailbeat frequencies (direct method); and 4) investigating the temporal and spatial variability of the flow field that might explain differences between direct and indirect estimates of energy expenditure. Velocities were measured in a 10cm grid spacing using Acoustic Doppler Velocimetry and fish locations were observed using underwater videogrammetry. Results indicate that scale of observation matters. As predicted, the mean and variance of velocity decreases with coarsening resolution of the flow field observations, illustrating how observed velocities are compressed into a narrower and lower range at coarser scales relative to finer scales. This trend of compressed variability also occurs for the locations where fish were observed, indicating that coarser-resolution observations underestimate the magnitude and range of velocities that fish select. Regarding energy expenditure, in comparing estimates direct and indirect estimates, we find that energy expenditure from the indirect estimates is always lower than the direct estimates, though the degree depend on the scale of velocity measurements. These results are consistent with our hypothesis that coarser resolution observations underestimate the amount of energy that fish expend in resting and foraging, but also indicate that velocity-based measurements generally underestimate energy expenditure by fish. Spatial and temporal variability of velocities do not fully explain the discrepancies between direct and indirect estimates in energy

  9. An evaluation of a bed instability index as an indicator of habitat quality in mountain streams of the northwestern United States.

    Science.gov (United States)

    Kusnierz, Paul C; Holbrook, Christopher M; Feldman, David L

    2015-08-01

    Managers of aquatic resources benefit from indices of habitat quality that are reproducible and easy to measure, demonstrate a link between habitat quality and biota health, and differ between human-impacted (i.e., managed) and reference (i.e., nonimpacted or minimally impacted) conditions. The instability index (ISI) is an easily measured index that describes the instability of a streambed by relating the tractive force of a stream at bankfull discharge to the median substrate size. Previous studies have linked ISI to biological condition but have been limited to comparisons of sites within a single stream or among a small number of streams. We tested ISI as an indicator of human impact to habitat and biota in mountain streams of the northwestern USA. Among 1428 sites in six northwestern states, ISI was correlated with other habitat measures (e.g., residual pool depth, percent fine sediment) and indices of biotic health (e.g., number of intolerant macroinvertebrate taxa, fine sediment biotic index) and differed between managed and reference sites across a range of stream types and ecoregions. While ISI could be useful in mountain streams throughout the world, this index may be of particular interest to aquatic resource managers in the northwestern USA where a large dataset, from which ISI can be calculated, exists. PMID:26189618

  10. Aquatic biological communities and associated habitats at selected sites in the Big Wood River Watershed, south-central Idaho, 2014

    Science.gov (United States)

    MacCoy, Dorene E.; Short, Terry M.

    2016-09-28

    Assessments of streamflow (discharge) parameters, water quality, physical habitat, and biological communities were completed between May and September 2014 as part of a monitoring program in the Big Wood River watershed of south-central Idaho. The sampling was conducted by the U.S. Geological Survey in cooperation with Blaine County, Trout Unlimited, the Nature Conservancy, and the Wood River Land Trust to help identify the status of aquatic resources at selected locations in the watershed. Information in this report provides a basis with which to evaluate and monitor the long-term health of the Big Wood River and its major tributaries. Sampling sites were co-located with existing U.S. Geological Survey streamgaging stations: three on the main stem Big Wood River and four on the North Fork Big Wood River (North Fork), Warm Springs Creek (Warm Sp), Trail Creek (Trail Ck), and East Fork Big Wood River (East Fork) tributaries.The analytical results and quality-assurance information for water quality, physical habitat, and biological community samples collected at study sites during 2 weeks in September 2014 are summarized. Water-quality data include concentrations of major nutrients, suspended sediment, dissolved oxygen, and fecal-coliform bacteria. To assess the potential effects of nutrient enrichment on algal growth, concentrations of periphyton biomass (chlorophyll-a and ash free dry weight) in riffle habitats were determined at each site. Physical habitat parameters include stream channel morphology, habitat volume, instream structure, substrate composition, and riparian vegetative cover. Biological data include taxa richness, abundance, and stream-health indicator metrics for macroinvertebrate and fish communities. Statistical summaries of the water-quality, habitat, and biological data are provided along with discussion of how these findings relate to the health of aquatic resources in the Big Wood River watershed.Seasonal discharge patterns using statistical

  11. Aquatic biological communities and associated habitats at selected sites in the Big Wood River Watershed, south-central Idaho, 2014

    Science.gov (United States)

    MacCoy, Dorene E.; Short, Terry M.

    2016-09-28

    Assessments of streamflow (discharge) parameters, water quality, physical habitat, and biological communities were completed between May and September 2014 as part of a monitoring program in the Big Wood River watershed of south-central Idaho. The sampling was conducted by the U.S. Geological Survey in cooperation with Blaine County, Trout Unlimited, the Nature Conservancy, and the Wood River Land Trust to help identify the status of aquatic resources at selected locations in the watershed. Information in this report provides a basis with which to evaluate and monitor the long-term health of the Big Wood River and its major tributaries. Sampling sites were co-located with existing U.S. Geological Survey streamgaging stations: three on the main stem Big Wood River and four on the North Fork Big Wood River (North Fork), Warm Springs Creek (Warm Sp), Trail Creek (Trail Ck), and East Fork Big Wood River (East Fork) tributaries.The analytical results and quality-assurance information for water quality, physical habitat, and biological community samples collected at study sites during 2 weeks in September 2014 are summarized. Water-quality data include concentrations of major nutrients, suspended sediment, dissolved oxygen, and fecal-coliform bacteria. To assess the potential effects of nutrient enrichment on algal growth, concentrations of periphyton biomass (chlorophyll-a and ash free dry weight) in riffle habitats were determined at each site. Physical habitat parameters include stream channel morphology, habitat volume, instream structure, substrate composition, and riparian vegetative cover. Biological data include taxa richness, abundance, and stream-health indicator metrics for macroinvertebrate and fish communities. Statistical summaries of the water-quality, habitat, and biological data are provided along with discussion of how these findings relate to the health of aquatic resources in the Big Wood River watershed.Seasonal discharge patterns using statistical

  12. Seasonal variation in soil seed bank size and species composition of selected habitat types in Maputaland, South Africa

    Directory of Open Access Journals (Sweden)

    M. J. S. Kellerman

    2007-12-01

    Full Text Available Seasonal variation in seed bank size and species composition of five selected habitat types within the Tembe Elephant Park. South Africa, was investigated. At three-month intervals, soil samples were randomly collected from five different habitat types: a, Licuati forest; b, Licuati thicket; c, a bare or sparsely vegetated zone surrounding the forest edge, referred to as the forest/grassland ecotone; d, grassland; and e, open woodland. Most species in the seed bank flora were either grasses, sedges, or forbs, with hardly any evidence of woody species. The Licuati forest and thicket soils produced the lowest seed densities in all seasons.  Licuati forest and grassland seed banks showed a two-fold seasonal variation in size, those of the Licuati thicket and woodland a three-fold variation in size, whereas the forest/grassland ecotone maintained a relatively large seed bank all year round. The woodland seed bank had the highest species richness, whereas the Licuati forest and thicket soils were poor in species. Generally, it was found that the greatest correspondence in species composition was between the Licuati forest and thicket, as well as the forest/grassland ecotone and grassland seed bank floras.

  13. Secondary Waste Form Down-Selection Data Package—Fluidized Bed Steam Reforming Waste Form

    Energy Technology Data Exchange (ETDEWEB)

    Qafoku, Nikolla; Westsik, Joseph H.; Strachan, Denis M.; Valenta, Michelle M.; Pires, Richard P.

    2011-09-12

    The Hanford Site in southeast Washington State has 56 million gallons of radioactive and chemically hazardous wastes stored in 177 underground tanks (ORP 2010). The U.S. Department of Energy (DOE), Office of River Protection (ORP), through its contractors, is constructing the Hanford Tank Waste Treatment and Immobilization Plant (WTP) to convert the radioactive and hazardous wastes into stable glass waste forms for disposal. Within the WTP, the pretreatment facility will receive the retrieved waste from the tank farms and separate it into two treated process streams. These waste streams will be vitrified, and the resulting waste canisters will be sent to offsite (high-level waste [HLW]) and onsite (immobilized low-activity waste [ILAW]) repositories. As part of the pretreatment and ILAW processing, liquid secondary wastes will be generated that will be transferred to the Effluent Treatment Facility (ETF) on the Hanford Site for further treatment. These liquid secondary wastes will be converted to stable solid waste forms that will be disposed of in the Integrated Disposal Facility (IDF). To support the selection of a waste form for the liquid secondary wastes from WTP, Washington River Protection Solutions (WRPS) has initiated secondary waste form testing work at Pacific Northwest National Laboratory (PNNL). In anticipation of a down-selection process for a waste form for the Solidification Treatment Unit to be added to the ETF, PNNL is developing data packages to support that down-selection. The objective of the data packages is to identify, evaluate, and summarize the existing information on the four waste forms being considered for stabilizing and solidifying the liquid secondary wastes. At the Hanford Site, the FBSR process is being evaluated as a supplemental technology for treating and immobilizing Hanford LAW radioactive tank waste and for treating secondary wastes from the WTP pretreatment and LAW vitrification processes.

  14. Inter- and intra-specific diurnal habitat selection of zooplankton during the spring bloom observed by Video Plankton Recorder

    DEFF Research Database (Denmark)

    Sainmont, Julie; Gislason, Astthor; Heuschele, Jan;

    2014-01-01

    Diel vertical migration (DVM) is a common behavior adopted by zooplankton species. DVM is a prominent adaptation for avoiding visual predation during daylight hours and still being able to feed on surface phytoplankton blooms during night. Here, we report on a DVM study using a Video Plankton...... a large abundance of copepods performing DVM (up during night and down during day). Migration behavior was expressed differently among the abundant groups with either a strong DVM (euphausiids), an absence of DVM (i.e., permanently deep; ostracods) or a marked DVM, driven by strong surface avoidance...... exposure) and thereby is likely to influence both state (hunger, weight and stage) and survival. The results suggest that the copepods select day and night time habitats with similar light levels (~10−9 μmol photon s−1 m−2). Furthermore, Calanus spp. displayed state-dependent behavior, with DVM most...

  15. Predicting the future distribution of Polar Bear Habitat in the polar basin from resource selection functions applied to 21st century general circulation model projections of sea ice

    Science.gov (United States)

    Durner, George M.; Douglas, David C.; Nielson, Ryan M.; Amstrup, Steven C.; McDonald, Trent L.

    2007-01-01

    Predictions of polar bear (Ursus maritimus) habitat distribution in the Arctic polar basin during the 21st century were developed to help understand the likely consequences of anticipated sea ice reductions on polar bear populations. We used location data from satellite-collared polar bears and environmental data (e.g., bathymetry, coastlines, and sea ice) collected between 1985–1995 to build habitat use models called Resource Selection Functions (RSF). The RSFs described habitats polar bears preferred in each of four seasons: summer (ice minimum), autumn (growth), winter (ice maximum) and spring (melt). When applied to the model source data and to independent data (1996–2006), the RSFs consistently identified habitats most frequently used by polar bears. We applied the RSFs to monthly maps of 21st century sea ice concentration predicted by 10 general circulation models (GCM) described in the International Panel of Climate Change Fourth Assessment Report. The 10 GCMs we used had high concordance between their simulations of 20th century summer sea ice extent and the actual ice extent derived from passive microwave satellite observations. Predictions of the amount and rate of change in polar bear habitat varied among GCMs, but all GCMs predicted net habitat losses in the polar basin during the 21st century. Projected losses in the highest-valued RSF habitat (optimal habitat) were greatest in the peripheral seas of the polar basin, especially the Chukchi Sea and Barents Sea. Losses were least in high-latitude regions where RSFs predicted an initial increase in optimal habitat followed by a modest decline. The largest seasonal reductions in habitat were predicted for spring and summer. Average area of optimal polar bear habitat during summer in the polar basin declined from an observed 1.0 million km2 in 1985–1995 (baseline) to a projected multi-model average of 0.58 million km2 in 2045–2054 (-42% change), 0.36 million km2 in 2070–2079 (-64% change), and 0

  16. High-tide habitat choice : insights from modelling roost selection by shorebirds around a tropical bay

    NARCIS (Netherlands)

    Rogers, Danny I.; Battley, Phil F.; Piersma, Theunis; Van Gils, Jan A.; Rogers, Ken G.

    2006-01-01

    High tides force shorebirds from intertidal feeding areas to sites known as roosts. We investigated the roost selection of great knots, Calidris tenuirostris, and red knots, Calidris canutus, on a tropical coastline in northwestern Australia, assessing several roost attributes and recording the freq

  17. Linking habitat selection to fitness-related traits in herbivores: the role of the energy landscape.

    Science.gov (United States)

    Long, Ryan A; Bowyer, R T; Porter, Warren P; Mathewson, Paul; Monteith, Kevin L; Findholt, Scott L; Dick, Brian L; Kie, John G

    2016-07-01

    Animals may partially overcome environmental constraints on fitness by behaviorally adjusting their exposure to costs and supplies of energy. Few studies, however, have linked spatiotemporal variation in the energy landscape to behaviorally mediated measures of performance that ostensibly influence individual fitness. We hypothesized that strength of selection by North American elk (Cervus elaphus) for areas that reduced costs of thermoregulation and activity, and increased access to high-quality forage, would influence four energetically mediated traits related to fitness: birth mass of young, nutritional condition of adult females at the onset of winter, change in nutritional condition of females between spring and winter, and neonatal survival. We used a biophysical model to map spatiotemporally explicit costs of thermoregulation and activity experienced by elk in a heterogeneous landscape. We then combined model predictions with data on forage characteristics, animal locations, nutritional condition, and mass and survival of young to evaluate behaviorally mediated effects of the energy landscape on fitness-related traits. During spring, when high-quality forage was abundant, female elk that consistently selected low-cost areas before parturition gave birth to larger young than less-selective individuals, and birth mass had a strong, positive influence on probability of survival. As forage quality declined during autumn, however, lactating females that consistently selected the highest quality forage available accrued more fat and entered winter in better condition than less-selective individuals. Results of our study highlight the importance of understanding the dynamic nature of energy landscapes experienced by free-ranging animals. PMID:27003702

  18. Biofilm history and oxygen availability interact to affect habitat selection in a marine invertebrate.

    Science.gov (United States)

    Lagos, Marcelo E; White, Craig R; Marshall, Dustin J

    2016-07-01

    In marine systems, oxygen availability varies at small temporal and spatial scales, such that current oxygen levels may not reflect conditions of the past. Different studies have shown that marine invertebrate larvae can select settlement sites based on local oxygen levels and oxygenation history of the biofilm, but no study has examined the interaction of both. The influence of normoxic and hypoxic water and oxygenation history of biofilms on pre-settlement behavior and settlement of the bryozoan Bugula neritina was tested. Larvae used cues in a hierarchical way: the oxygen levels in the water prime larvae to respond, the response to different biofilms is contingent on oxygen levels in the water. When oxygen levels varied throughout biofilm formation, larvae responded differently depending on the history of the biofilm. It appears that B. neritina larvae integrate cues about current and historical oxygen levels to select the appropriate microhabitat and maximize their fitness. PMID:27169475

  19. Conservation of endangered Lupinus mariae-josephae in its natural habitat by inoculation with selected, native Bradyrhizobium strains.

    Directory of Open Access Journals (Sweden)

    Albert Navarro

    Full Text Available Lupinus mariae-josephae is a recently discovered endemism that is only found in alkaline-limed soils, a unique habitat for lupines, from a small area in Valencia region (Spain. In these soils, L. mariae-josephae grows in just a few defined patches, and previous conservation efforts directed towards controlled plant reproduction have been unsuccessful. We have previously shown that L. mariae-josephae plants establish a specific root nodule symbiosis with bradyrhizobia present in those soils, and we reasoned that the paucity of these bacteria in soils might contribute to the lack of success in reproducing plants for conservation purposes. Greenhouse experiments using L. mariae-josephae trap-plants showed the absence or near absence of L. mariae-josephae-nodulating bacteria in "terra rossa" soils of Valencia outside of L. mariae-josephae plant patches, and in other "terra rossa" or alkaline red soils of the Iberian Peninsula and Balearic Islands outside of the Valencia L. mariae-josephae endemism region. Among the bradyrhizobia able to establish an efficient symbiosis with L. mariae-josephae plants, two strains, LmjC and LmjM3 were selected as inoculum for seed coating. Two planting experiments were carried out in consecutive years under natural conditions in areas with edapho-climatic characteristics identical to those sustaining natural L. mariae-josephae populations, and successful reproduction of the plant was achieved. Interestingly, the successful reproductive cycle was absolutely dependent on seedling inoculation with effective bradyrhizobia, and optimal performance was observed in plants inoculated with LmjC, a strain that had previously shown the most efficient behavior under controlled conditions. Our results define conditions for L. mariae-josephae conservation and for extension to alkaline-limed soil habitats, where no other known lupine can thrive.

  20. Assessing Greater Sage-Grouse Selection of Brood-Rearing Habitat Using Remotely-Sensed Imagery: Can Readily Available High-Resolution Imagery Be Used to Identify Brood-Rearing Habitat Across a Broad Landscape?

    Directory of Open Access Journals (Sweden)

    Matthew Westover

    Full Text Available Greater sage-grouse populations have decreased steadily since European settlement in western North America. Reduced availability of brood-rearing habitat has been identified as a limiting factor for many populations. We used radio-telemetry to acquire locations of sage-grouse broods from 1998 to 2012 in Strawberry Valley, Utah. Using these locations and remotely-sensed NAIP (National Agricultural Imagery Program imagery, we 1 determined which characteristics of brood-rearing habitat could be used in widely available, high resolution imagery 2 assessed the spatial extent at which sage-grouse selected brood-rearing habitat, and 3 created a predictive habitat model to identify areas of preferred brood-rearing habitat. We used AIC model selection to evaluate support for a list of variables derived from remotely-sensed imagery. We examined the relationship of these explanatory variables at three spatial extents (45, 200, and 795 meter radii. Our top model included 10 variables (percent shrub, percent grass, percent tree, percent paved road, percent riparian, meters of sage/tree edge, meters of riparian/tree edge, distance to tree, distance to transmission lines, and distance to permanent structures. Variables from each spatial extent were represented in our top model with the majority being associated with the larger (795 meter spatial extent. When applied to our study area, our top model predicted 75% of naïve brood locations suggesting reasonable success using this method and widely available NAIP imagery. We encourage application of our methodology to other sage-grouse populations and species of conservation concern.

  1. Assessing Greater Sage-Grouse Selection of Brood-Rearing Habitat Using Remotely-Sensed Imagery: Can Readily Available High-Resolution Imagery Be Used to Identify Brood-Rearing Habitat Across a Broad Landscape?

    Science.gov (United States)

    Westover, Matthew; Baxter, Jared; Baxter, Rick; Day, Casey; Jensen, Ryan; Petersen, Steve; Larsen, Randy

    2016-01-01

    Greater sage-grouse populations have decreased steadily since European settlement in western North America. Reduced availability of brood-rearing habitat has been identified as a limiting factor for many populations. We used radio-telemetry to acquire locations of sage-grouse broods from 1998 to 2012 in Strawberry Valley, Utah. Using these locations and remotely-sensed NAIP (National Agricultural Imagery Program) imagery, we 1) determined which characteristics of brood-rearing habitat could be used in widely available, high resolution imagery 2) assessed the spatial extent at which sage-grouse selected brood-rearing habitat, and 3) created a predictive habitat model to identify areas of preferred brood-rearing habitat. We used AIC model selection to evaluate support for a list of variables derived from remotely-sensed imagery. We examined the relationship of these explanatory variables at three spatial extents (45, 200, and 795 meter radii). Our top model included 10 variables (percent shrub, percent grass, percent tree, percent paved road, percent riparian, meters of sage/tree edge, meters of riparian/tree edge, distance to tree, distance to transmission lines, and distance to permanent structures). Variables from each spatial extent were represented in our top model with the majority being associated with the larger (795 meter) spatial extent. When applied to our study area, our top model predicted 75% of naïve brood locations suggesting reasonable success using this method and widely available NAIP imagery. We encourage application of our methodology to other sage-grouse populations and species of conservation concern.

  2. Selective habitat utilisation and impact on vegetation by African elephant within a heterogeneous landscape

    Directory of Open Access Journals (Sweden)

    A. Steyn

    2001-07-01

    Full Text Available Since 1992, a total of 33 elephants have been reintroduced to a 31 000 ha game-fenced section of the Songimvelo Game Reserve in the Barberton Mountainland, South Africa. The impact from elephant was assessed on the attainment of the primary management objectives which are the conservation of plant community and plant species diversity. A total of 160 semi-quantitative plots were systematically sampled along foraging paths. Vegetation was assessed in terms of dominant species composition and species utilised. Elephant activity is mostly confined to a rugged 1 200 ha portion of the reserve. Forest, thickets and woodlands are positively selected, whereas shrublands and grasslands are little utilised. A total of 73 woody species were recorded within the sample plots. Thirtynine of these species were utilised in the woodlands, 31 in the forest and thickets, and only 18 in the shrublands. Acacia ataxacantha, Dalbergia armata and Acacia caffra are ranked highest in dominance and in utilisation values. In contrast, Cussonia spicata and Pterocarpus angolensis are less common but are much selected. Continued utilisation at present levels could significantly threaten their persistence. These preliminary results indicate that the present low overall density of elephants relative to many other conservation areas already has a marked effect on certain plant species. Absolute elephant density figures are relatively meaningless within a heterogeneous landscape. The specific community and species make-up of the landscape needs to be taken into account for the determination of bounds to elephant numbers in order to ensure the maintenance of present plant species diversity levels.

  3. Abundance and distribution of selected elements in soils, stream sediments, and selected forage plants from desert tortoise habitats in the Mojave and Colorado deserts, USA

    Science.gov (United States)

    Chaffee, M.A.; Berry, K.H.

    2006-01-01

    A baseline and background chemical survey was conducted in southeastern California, USA, to identify potential sources of toxicants in natural and anthropogenically-altered habitats of the threatened desert tortoise (Gopherus agassizii). Soil, stream sediment, and plant samples were collected from six tortoise habitat study areas in the Mojave and Colorado deserts and analysed for up to 66 different elements. The chemical analyses provided new information on the abundances and distributions of selected elements in this region. Soil, stream-sediment, and plant analyses showed distinct variations in bulk chemistries from locality to locality. Variations were, in general, consistent with the many types of exposed rock units in the region, their highly variable bulk mineralogies, and chemical contents. Of elements in soils that might have been toxic to tortoises, only As seemed to be anomalous region-wide. Some soil and plant anomalies were clearly anthropogenic. In the Rand and Atolia mining districts, soil anomalies for As, Au, Cd, Hg, Sb, and(or) W and plant anomalies for As, Sb, and(or) W extend as far as ???15 km outward from the present area of mining; soils containing anomalous Hg were found at least 6 km away from old piles of tailings. The anomalous concentrations of As and Hg may have been the source of elevated levels of these elements found in ill tortoises from the region. In the Goldstone mining district, soil anomalies extended several km from the mining area. These areas probably represented anthropogenic surface contamination of dust redistributed by wind, vehicles, and rainfall. One of two study areas transected by a paved road (Chemehuevi Valley) showed weakly elevated levels of Pb, which extended as far as ???22 m from the pavement edge and were probably related to vehicle exhaust. No soil or plant samples from historically used military areas (Goldstone, Goffs, Chemehuevi Valley, Chuckwalla Bench) contained anomalous concentrations of the elements

  4. Wavelength Selection For Laser Raman Spectroscopy of Putative Martian Habitats and Biomolecules

    Science.gov (United States)

    Wynn-Williams, D. D.; Newton, E. M. G.; Edwards, H. G. M.

    Pigments are key potential biomarkers for any former life on Mars because of the selective pressure of solar radiation on any biological system that could have evolved at its surface. We have found that the near -Infrared laser Raman spectrometer available to use was eminently suitable for diagnostic analysis of pigments because of their minimal autofluorescence at its 1064 nm excitation wav elength. However, we have now evaluated a diverse range of excitation wavelengths to confirm this choice, to ensure that we have the best technique to seek for pigments and their derivatives from any former surface life on Mars. The Raman is weak relative to fluorescence, which results in elevated baseline and concurrent swamping of Raman bands. We confirm the molecular information available from near-IR FT Raman spectra for two highly pigmented UV-tolerant epilithic Antarctic lichens (Acarospora chlorop hana and Caloplaca saxicola) from Victoria Land, a whole endolithic microbial community and endolithic cyanobacterium Chroococcidiopsis from within translucent sandstone of the Trans -Antarctic Mountains, and the free- living cyanobacterium Nostoc commune from Alexander Island, Antarctic Peninsula region. We also show that much of the information we require on biomolecules is not evident from lasers of shorter wavelengths. A miniature 1064 nm Raman spectrometer with an In-Ga-As detector sensitive to IR is being developed by Montana State University (now existing as a prototype) as the prime instrument for a proposed UK-led Mars rover mission (Vanguard). Preliminary spectra from this system confirm the suitability of the near-IR laser.

  5. Getting Rid of Bed Bugs

    Science.gov (United States)

    ... how you select a company. Related Information Collaborative Strategy on Bed Bugs - highlights ways that all levels of government, community, academia and private industry can work together to reduce bed bugs across ...

  6. Hydrophobic interaction ligand selection and scale-up of an expanded bed separation of an intracellular enzyme from Saccharomyces cerevisiae.

    Science.gov (United States)

    Smith, M P; Bulmer, M A; Hjorth, R; Titchener-Hooker, N J

    2002-08-30

    A prototype Streamline-Phenyl matrix was evaluated in a hydrophobic interaction mode for the direct recovery of alcohol dehydrogenase (ADH) from yeast cell homogenate. At 5% breakthrough of ADH, a yield of 100% was obtained for a dynamic expanded bed capacity of 240 U(ADH)/ml matrix with a purification factor of 9.2. This compared with a dynamic capacity of 3013 U(ADH)/ml matrix for the packed bed equivalent and a purification factor of 18. In both systems the purification factor was found to increase simultaneously with a decrease in yield as the load of homogenate or breakthrough of ADH was increased. The expanded bed mode of operation conferred considerable robustness with respect to process fouling. No loss in yield was seen over five cycles of repeat loading with an unclarified homogenate. By contrast the packed bed media showed a decrease in yield from 86 to 56% over the same period. Successful scale up of the expanded bed protocol for a 20% breakthrough was demonstrated over a fourfold increase in column diameter. The application of hydrophobic interaction chromatography mediated expanded bed adsorption and its scale-up is discussed in the context of large-scale operations.

  7. Effects of an experimental enrichment of instream habitat heterogeneity on the stream bed morphology and chironomid community of a straightened section in a sandy lowland stream.

    Science.gov (United States)

    Spänhoff, Bernd; Riss, Wolfgang; Jäkel, Paul; Dakkak, Nadja; Meyer, Elisabeth I

    2006-02-01

    A straightened stream stretch with poor habitat heterogeneity was divided into a "control" section with a low amount of submerged woody debris and an experimentally "wood-enriched" downstream section to study the effect of enhanced habitat diversity on the benthic invertebrate community. The downstream section was enriched by fixing 25 wood packages constructed from 9-10 branches on the stream bottom. Succession processes occurring in the two stream sections were compared by chironomid exuviae drift from July to November 2000 and from April to August 2001. During the first sampling period, more drifting chironomid exuviae (medians of control vs. wood-enriched: 446 vs. 331, no significant difference) and total number of taxa (44 vs. 36, Wilcoxon signed-rank test P = 0.019) were recorded for the control section. Although species compositions of both stream sections were highly similar (Sørensen index: 0.83) the diversity in the wood-enriched section was distinctly lower compared to the control section (Shannon-Weaver index: 1.19 vs. 1.50). During the second sampling period, exuviae numbers remained higher in the control section (median: 326 vs. 166), but total numbers of taxa were nearly equal (51 vs. 49), as well as species diversity (Shannon-Weaver index: 1.67 vs. 1.64). The lower chironomid diversity observed during the first sampling period coincided with a gradual but significant change of the streambed morphology in the wood-enriched section. There, the initially more U-shaped profile (V/U = 0.81 +/- 0.37) had turned into a pronounced V shape (V/U = 1.14 +/- 0.21), whereas the control section retained its unaltered U shape (V/U = 0.62-0.75). This small-scale study on experimental of woody debris in sandy lowland streams showed that the negative impact of increased hydraulic disturbance of the existing streambed more than outweighed any positive impact resulting from the increase in woody debris. PMID:16391966

  8. Riparian and Associated Habitat Characteristics Related to Nutrient Concentrations and Biological Responses of Small Streams in Selected Agricultural Areas, United States, 2003-04

    Science.gov (United States)

    Zelt, Ronald B.; Munn, Mark D.

    2009-01-01

    Physical factors, including both in-stream and riparian habitat characteristics that limit biomass or otherwise regulate aquatic biological condition, have been identified by previous studies. However, linking the ecological significance of nutrient enrichment to habitat or landscape factors that could allow for improved management of streams has proved to be a challenge in many regions, including agricultural landscapes, where many ecological stressors are strong and the variability among watersheds typically is large. Riparian and associated habitat characteristics were sampled once during 2003-04 for an intensive ecological and nutrients study of small perennial streams in five contrasting agricultural landscapes across the United States to determine how biological communities and ecosystem processes respond to varying levels of nutrient enrichment. Nutrient concentrations were determined in stream water at two different sampling times per site and biological samples were collected once per site near the time of habitat characterization. Data for 141 sampling sites were compiled, representing five study areas, located in parts of the Delmarva Peninsula (Delaware and Maryland), Georgia, Indiana, Ohio, Nebraska, and Washington. This report examines the available data for riparian and associated habitat characteristics to address questions related to study-unit contrasts, spatial scale-related differences, multivariate correlation structure, and bivariate relations between selected habitat characteristics and either stream nutrient conditions or biological responses. Riparian and associated habitat characteristics were summarized and categorized into 22 groups of habitat variables, with 11 groups representing land-use and land-cover characteristics and 11 groups representing other riparian or in-stream habitat characteristics. Principal components analysis was used to identify a reduced set of habitat variables that describe most of the variability among the

  9. Intense habitat-specific fisheries-induced selection at the molecular Pan I locus predicts imminent collapse of a major cod fishery.

    Directory of Open Access Journals (Sweden)

    Einar Arnason

    Full Text Available Predation is a powerful agent in the ecology and evolution of predator and prey. Prey may select multiple habitats whereby different genotypes prefer different habitats. If the predator is also habitat-specific the prey may evolve different habitat occupancy. Drastic changes can occur in the relation of the predator to the evolved prey. Fisheries exert powerful predation and can be a potent evolutionary force. Fisheries-induced selection can lead to phenotypic changes that influence the collapse and recovery of the fishery. However, heritability of the phenotypic traits involved and selection intensities are low suggesting that fisheries-induced evolution occurs at moderate rates at decadal time scales. The Pantophysin I (Pan I locus in Atlantic cod (Gadus morhua, representing an ancient balanced polymorphism predating the split of cod and its sister species, is under an unusual mix of balancing and directional selection including current selective sweeps. Here we show that Pan I alleles are highly correlated with depth with a gradient of 0.44% allele frequency change per meter. AA fish are shallow-water and BB deep-water adapted in accordance with behavioral studies using data storage tags showing habitat selection by Pan I genotype. AB fish are somewhat intermediate although closer to AA. Furthermore, using a sampling design covering space and time we detect intense habitat-specific fisheries-induced selection against the shallow-water adapted fish with an average 8% allele frequency change per year within year class. Genotypic fitness estimates (0.08, 0.27, 1.00 of AA, AB, and BB respectively predict rapid disappearance of shallow-water adapted fish. Ecological and evolutionary time scales, therefore, are congruent. We hypothesize a potential collapse of the fishery. We find that probabilistic maturation reaction norms for Atlantic cod at Iceland show declining length and age at maturing comparable to changes that preceded the collapse of

  10. A management-oriented framework for selecting metrics used to assess habitat- and path-specific quality in spatially structured populations

    Science.gov (United States)

    Sam Nicol,; Ruscena Wiederholt,; Diffendorfer, James E.; Brady Mattsson,; Thogmartin, Wayne E.; Semmens, Darius J.; Laura Lopez-Hoffman,; Ryan Norris,

    2016-01-01

    Mobile species with complex spatial dynamics can be difficult to manage because their population distributions vary across space and time, and because the consequences of managing particular habitats are uncertain when evaluated at the level of the entire population. Metrics to assess the importance of habitats and pathways connecting habitats in a network are necessary to guide a variety of management decisions. Given the many metrics developed for spatially structured models, it can be challenging to select the most appropriate one for a particular decision. To guide the management of spatially structured populations, we define three classes of metrics describing habitat and pathway quality based on their data requirements (graph-based, occupancy-based, and demographic-based metrics) and synopsize the ecological literature relating to these classes. Applying the first steps of a formal decision-making approach (problem framing, objectives, and management actions), we assess the utility of metrics for particular types of management decisions. Our framework can help managers with problem framing, choosing metrics of habitat and pathway quality, and to elucidate the data needs for a particular metric. Our goal is to help managers to narrow the range of suitable metrics for a management project, and aid in decision-making to make the best use of limited resources.

  11. Using stochastic gradient boosting to infer stopover habitat selection and distribution of Hooded Cranes Grus monacha during spring migration in Lindian, Northeast China.

    Directory of Open Access Journals (Sweden)

    Tianlong Cai

    Full Text Available The Hooded Crane (Grus monacha is a globally vulnerable species, and habitat loss is the primary cause of its decline. To date, little is known regarding the specific habitat needs, and stopover habitat selection in particular, of the Hooded Crane. In this study we used stochastic gradient boosting (TreeNet to develop three specific habitat selection models for roosting, daytime resting, and feeding site selection. In addition, we used a geographic information system (GIS combined with TreeNet to develop a species distribution model. We also generated a digital map of the relative occurrence index (ROI of this species at daytime resting sites in the study area. Our study indicated that the water depth, distance to village, coverage of deciduous leaves, open water area, and density of plants were the major predictors of roosting site selection. For daytime resting site selection, the distance to wetland, distance to farmland, and distance to road were the primary predictors. For feeding site selection, the distance to road, quantity of food, plant coverage, distance to village, plant density, distance to wetland, and distance to river were contributing factors, and the distance to road and quantity of food were the most important predictors. The predictive map showed that there were two consistent multi-year daytime resting sites in our study area. Our field work in 2013 using systematic ground-truthing confirmed that this prediction was accurate. Based on this study, we suggest that Lindian plays an important role for migratory birds and that cultivation practices should be adjusted locally. Furthermore, public education programs to promote the concept of the harmonious coexistence of humans and cranes can help successfully protect this species in the long term and eventually lead to its delisting by the IUCN.

  12. Evaluation of Selected Chemical Processes for Production of Low-cost Silicon, Phase 3. [using a fluidized bed reactor

    Science.gov (United States)

    Blocher, J. M., Jr.; Browning, M. F.

    1979-01-01

    The construction and operation of an experimental process system development unit (EPSDU) for the production of granular semiconductor grade silicon by the zinc vapor reduction of silicon tetrachloride in a fluidized bed of seed particles is presented. The construction of the process development unit (PDU) is reported. The PDU consists of four critical units of the EPSDU: the fluidized bed reactor, the reactor by product condenser, the zinc vaporizer, and the electrolytic cell. An experimental wetted wall condenser and its operation are described. Procedures are established for safe handling of SiCl4 leaks and spills from the EPSDU and PDU.

  13. Nest-site selection and reproductive success of greater sage-grouse in a fire-affected habitat of northwestern Nevada

    Science.gov (United States)

    Lockyer, Zachary B.; Coates, Peter S.; Casazza, Michael L.; Espinosa, Shawn; Delehanty, David J.

    2015-01-01

    Identifying links between micro-habitat selection and wildlife reproduction is imperative to population persistence and recovery. This information is particularly important for landscape species such as greater sage-grouse (Centrocercus urophasianus; sage-grouse). Although this species has been widely studied, because environmental factors can affect sage-grouse populations, local and regional studies are crucial for developing viable conservation strategies. We studied the habitat-use patterns of 71 radio-marked sage-grouse inhabiting an area affected by wildfire in the Virginia Mountains of northwestern Nevada during 2009–2011 to determine the effect of micro-habitat attributes on reproductive success. We measured standard vegetation parameters at nest and random sites using a multi-scale approach (range = 0.01–15,527 ha). We used an information-theoretic modeling approach to identify environmental factors influencing nest-site selection and survival, and determine whether nest survival was a function of resource selection. Sage-grouse selected micro-sites with greater shrub canopy cover and less cheatgrass (Bromus tectorum) cover than random sites. Total shrub canopy, including sagebrush (Artemisia spp.) and other shrub species, at small spatial scales (0.8 ha and 3.1 ha) was the single contributing selection factor to higher nest survival. These results indicate that reducing the risk of wildfire to maintain important sagebrush habitats could be emphasized in sage-grouse conservation strategies in Nevada. Managers may seek to mitigate the influx of annual grass invasion by preserving large intact sagebrush-dominated stands with a mixture of other shrub species. For this area of Nevada, the results suggest that ≥40% total shrub canopy cover in sage-grouse nesting areas could yield improved reproductive success. 

  14. The effect of habitat conditions on the abundance of populations and selected individual and floral traits of Impatiens glandulifera Royle

    Directory of Open Access Journals (Sweden)

    Kostrakiewicz-Gierałt Kinga

    2015-03-01

    Full Text Available The effect of site conditions on the abundance of populations of I. glandulifera, selected individual features (height and width of stems, number of whorls and side branches, flower production, and floral traits (total length of flowers, length and width of lower sepal, spur length were investigated in years 2013-14. Observations were conducted on fallow land, at roadsides, along riverbanks and edges of a riparian forest as well as in a willow thicket and a riparian forest inside located in the Vistula River valley in southern Poland. In these stands, taken successively, light availability gradually diminished, while plant canopy height and soil moisture increased. The low abundance of the population on the fallow land may have been caused by low soil humidity triggering seedling mortality, whereas the low abundance in the interior of the riparian forest may have been due to seasonal water stagnation hampering the development of offspring. The increasing values of individual traits from the fallow land to riparian forest edge might be linked to growing lateral shade, whereas the much lower values in the willow thicket and forest interior might be caused by full shade. Individuals growing on the fallow land, at roadsides, and along riverbanksproduced flowers with small total lengths and large lower sepals and spurs, whereas individuals occurring in willow thickets and riparian forests showed opposite tendency. The considerable stem dimensions and substantial production of large flowers may augment chances for successful resource capture and pollinator visits in open sites, while the reduced size of individuals and moderate production of small flowers may be sufficient for the maintenance of populations in closed habitats

  15. Fluidized bed steam reformed mineral waste form performance testing to support Hanford Supplemental Low Activity Waste Immobilization Technology Selection

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Pierce, E. M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bannochie, C. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Burket, P. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Cozzi, A. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Crawford, C. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Daniel, W. E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Herman, C. C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Miller, D. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Missimer, D. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Nash, C. A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Williams, M. F. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Brown, C. F. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Qafoku, N. P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Neeway, J. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Valenta, M. M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gill, G. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Swanberg, D. J. [Washington River Protection Solutions (WRPS), Richland, WA (United States); Robbins, R. A. [Washington River Protection Solutions (WRPS), Richland, WA (United States); Thompson, L. E. [Washington River Protection Solutions (WRPS), Richland, WA (United States)

    2015-10-01

    This report describes the benchscale testing with simulant and radioactive Hanford Tank Blends, mineral product characterization and testing, and monolith testing and characterization. These projects were funded by DOE EM-31 Technology Development & Deployment (TDD) Program Technical Task Plan WP-5.2.1-2010-001 and are entitled “Fluidized Bed Steam Reformer Low-Level Waste Form Qualification”, Inter-Entity Work Order (IEWO) M0SRV00054 with Washington River Protection Solutions (WRPS) entitled “Fluidized Bed Steam Reforming Treatability Studies Using Savannah River Site (SRS) Low Activity Waste and Hanford Low Activity Waste Tank Samples”, and IEWO M0SRV00080, “Fluidized Bed Steam Reforming Waste Form Qualification Testing Using SRS Low Activity Waste and Hanford Low Activity Waste Tank Samples”. This was a multi-organizational program that included Savannah River National Laboratory (SRNL), THOR® Treatment Technologies (TTT), Pacific Northwest National Laboratory (PNNL), Oak Ridge National Laboratory (ORNL), Office of River Protection (ORP), and Washington River Protection Solutions (WRPS). The SRNL testing of the non-radioactive pilot-scale Fluidized Bed Steam Reformer (FBSR) products made by TTT, subsequent SRNL monolith formulation and testing and studies of these products, and SRNL Waste Treatment Plant Secondary Waste (WTP-SW) radioactive campaign were funded by DOE Advanced Remediation Technologies (ART) Phase 2 Project in connection with a Work-For-Others (WFO) between SRNL and TTT.

  16. Very High Temperature Reactor (VHTR) Deep Burn Core and Fuel Analysis -- Complete Design Selection for the Pebble Bed Reactor

    Energy Technology Data Exchange (ETDEWEB)

    B. Boer; A. M. Ougouag

    2010-09-01

    The Deep-Burn (DB) concept focuses on the destruction of transuranic nuclides from used light water reactor fuel. These transuranic nuclides are incorporated into TRISO coated fuel particles and used in gas-cooled reactors with the aim of a fractional fuel burnup of 60 to 70% in fissions per initial metal atom (FIMA). This high performance is expected through the use of multiple recirculation passes of the fuel in pebble form without any physical or chemical changes between passes. In particular, the concept does not call for reprocessing of the fuel between passes. In principle, the DB pebble bed concept employs the same reactor designs as the presently envisioned low-enriched uranium core designs, such as the 400 MWth Pebble Bed Modular Reactor (PBMR-400). Although it has been shown in the previous Fiscal Year (2009) that a PuO2 fueled pebble bed reactor concept is viable, achieving a high fuel burnup, while remaining within safety-imposed prescribed operational limits for fuel temperature, power peaking and temperature reactivity feedback coefficients for the entire temperature range, is challenging. The presence of the isotopes 239-Pu, 240-Pu and 241-Pu that have resonances in the thermal energy range significantly modifies the neutron thermal energy spectrum as compared to a ”standard,” UO2-fueled core. Therefore, the DB pebble bed core exhibits a relatively hard neutron energy spectrum. However, regions within the pebble bed that are near the graphite reflectors experience a locally softer spectrum. This can lead to power and temperature peaking in these regions. Furthermore, a shift of the thermal energy spectrum with increasing temperature can lead to increased absorption in the resonances of the fissile Pu isotopes. This can lead to a positive temperature reactivity coefficient for the graphite moderator under certain operating conditions. The effort of this task in FY 2010 has focused on the optimization of the core to maximize the pebble discharge

  17. The abundance of premetamorphic newts (Triturus cristatus, T. marmoratus) as a function of habitat determinants: an a priori model selection approach.

    OpenAIRE

    Sstatecsny, M; Jehle, R; Schmidt, B R; Arntzen, J.W.

    2004-01-01

    Despite the key role of premetamorphic amphibians in experimental ecology, the factors affecting their abundance has received relatively little attention in natural settings. We applied a model selection approach with AIC (Akaike's Information Criterion) to predict the abundance of embryos and larvae of crested and marbled newts (Triturus cristatus and T. marmoratus) at 32 breeding sites in western France, based on 15 variables describing the aquatic habitat, and 10 variables describing the t...

  18. MICROTURBULENCE IN GRAVEL BED STREAMS

    Science.gov (United States)

    Papanicolaou, T.; Tsakiris, A. G.; Kramer, C. M.

    2009-12-01

    The overarching objective of this investigation was to evaluate the role of relative submergence on the formation and evolution of cluster microforms in gravel bed streams and its implications to bedload transport. Secondary objectives of this research included (1) a detailed analysis of mean flow measurements around a clast; and (2) a selected number of experimental runs where the mean flow characteristics are linked together with the bed micro-topography observations around a clast. It is hypothesized that the relative submergence is an important parameter in defining the feedback processes between the flow and clasts, which governs the flow patterns around the clasts, thus directly affecting the depositional patterns of the incoming sediments. To examine the validity of the hypothesis and meet the objectives of this research, 19 detailed experimental runs were conducted in a tilting, water recirculating laboratory flume under well-controlled conditions. A fixed array of clast-obstacles were placed atop a well-packed bed with uniform size glass beads. During the runs, multifractional spherical particles were fed upstream of the clast section at a predetermined rate. State-of-the-art techniques/instruments, such as imaging analysis software, Large Scale Particle Velocimeter (LSPIV) and an Acoustic Doppler Velocimetry (ADV) were employed to provide unique quantitative measurements for bedload fluxes, clast/clusters geomorphic patterns, and mean flow characteristics in the vicinity of the clusters. Different flow patterns were recorded for the high relative submergence (HRS) and low relative submergence (LRS) experimental runs. The ADV measurements provided improved insight about the governing flow mechanisms for the HRS runs. These mechanisms were described with flow upwelling at the center of the flume and downwelling occurring along the flume walls. Flow downwelling corresponded to an increase in the free surface velocity. Additionally, the visual observations

  19. Features of habitat selection by larger herbivorous mammals and the Ostrich in the Southern Kalahari conservation areas

    Directory of Open Access Journals (Sweden)

    P. T van der Walt

    1984-12-01

    Full Text Available A Chi-squares contingency table was used to extensively analise animal/habitat interactions in the southern Kalahari conservation areas between 1978 and 1982. The effect of changing environmental con- ditions on the distribution of five large mammalian species (eland Taurotragus oryx, gemsbok Oryx gazella, blue wildebeest Connochaetes taurinus, red hartebeest Alcelaphus buselaphus, springbok Antidorcas marsupialis and the ostrich Struthio camelus is indicated by definite seasonal preferences. A general habitat-use pattern, whereby each habitat type was utilised at some stage during the year by one or more species, as well as a response by the different species to other environmental attributes was found revealing an ecological balance which will be maintained only if the present physical size of the conservation areas in question is maintained indefinitely.

  20. The Comparative Study on Habitat Selection of Four Ungulates%4种有蹄类动物栖息地选择比较研究

    Institute of Scientific and Technical Information of China (English)

    岳建兵

    2014-01-01

    利用Vanderloge和Scavia选择指数方法研究了甘肃白水江国家级自然保护区羚牛(Budorcas taxicolor)、鬣羚(Capricornis sumatraensis)、斑羚(Naemorhedus goral)和毛冠鹿(Elaphodus cephalophus)4种有蹄类动物在栖息地选择上的差异。结果表明:体形小的种类更倾向于选择低海拔植被类型;地貌方面,斑羚倾向于脊部,毛冠鹿倾向于谷地,鬣羚倾向于坡面和谷地,羚牛呈现随机选择;羚牛、鬣羚、斑羚对5 km内的居民点表现出回避。4种动物对栖息地植被、地貌和居民点距离的选择,反映出其生态位的分化。%In this study,we investigated the difference of habitat selection patterns among four ungulates, Takin(Budorcas taxicolor),Serow(Capricornis sumatraensis),Goral(Naemorhedus goral)and Tufted deer (Elaphodus cephalophus)living in Baishuijiang National Nature Reserve,Gansu Province.This investiga-tion involved 3336 pieces of effective habitat selection data(vegetation,land form and distance from resi-dential area).We used Vanderloge and Scavia indexes to analyze these data in order to conclude a habitat selection preference of these four species.Our results indicate that small species prefer low-altitude hab-itat.In terms of topography,Goral prefers ridge,Tufed deer prefers valley,Serow prefers slopes and valley, while the selection pattern of Takin is at random.Except Tufted deer,all the rest three of these four spe-cies avoid using habitat less than 5 km away from their residential areas.Habitat selection patterns of these four species reflected the differentiation of their niches.

  1. Guidelines for seagrass restoration : Importance of habitat selection and donor population, spreading of risks, and ecosystem engineering effects

    NARCIS (Netherlands)

    van Katwijk, M. M.; Bos, A. R.; de Jonge, V. N.; Hanssen, L. S. A. M.; Hermus, D. C. R.; de Jong, D. J.

    2009-01-01

    Large-scale losses of seagrass beds have been reported for decades and lead to numerous restoration programs. From worldwide scientific literature and 20 years of seagrass restoration research in the Wadden Sea, we review and evaluate the traditional guidelines and propose new guidelines for seagras

  2. FORAGING BEHAVIOR AND SITE SELECTION OF BARNACLE GEESE BRANTA-LEUCOPSIS IN A TRADITIONAL AND NEWLY COLONIZED SPRING STAGING HABITAT

    NARCIS (Netherlands)

    BLACK, JM; OWEN, M

    1991-01-01

    For three weeks in May the Svalbard Barnacle Geese Branta leucopsis stop to feed on the archipelagos of the Helgeland district, up to 50 km out to sea off western Norway. However, since 1980 an increasing part of the population has moved to a newly exploited agricultural habitat closer to the mainla

  3. Classroom Modified Split-Root Technique and Its Application in a Plant Habitat Selection Experiment at the College Level

    Science.gov (United States)

    Elliott, Shannon S.; Winter, Peggy A.

    2011-01-01

    The split-root technique produces a plant with two equal root masses. Traditionally, the two root masses of the single plant are cultivated in adjacent pots with or without roots from competitors for the purpose of elucidating habitat preferences. We have tailored this technology for the classroom, adjusting protocols to match resources and time…

  4. Predator protection or similar habitat selection in red-breasted goose nesting associations : extremes along a continuum

    NARCIS (Netherlands)

    Quinn, JL; Prop, J; Kokorev, Y; Black, JM

    2003-01-01

    We tested the predator protection and similar habitat hypotheses in relation to red-breasted goose, Branta ruficollis, nesting associations. Geese began laying 1-3 weeks after all associated species. In almost all cases they nested on the mainland only if raptors were also present and always followe

  5. Breeding habitat selection of an endangered species in an arid zone: the case of Alytes dickhilleni Arntzen & García-París, 1995

    Directory of Open Access Journals (Sweden)

    Andrés Egea-Serrano

    2006-11-01

    Full Text Available The influence of environmental variables on the selection of a particular water body as breeding habitat by Alytes dickhilleni was studied in the southeastern and most arid zone of its distribution range. From November 2002 to October 2003, 50 water bodies were monitored in the south east of the Iberian Peninsula. Environmental data were submitted to a stepwise logistic regression analysis at macrohabitat, water body typology and microhabitat scales in order to establish the main factors influencing the use of a given water body as breeding habitat by this species. Statistical analysis showed that the reproduction of Alytes dickhilleni is associated with the macrohabitat variable topography, and the water body typology. This species breeds mainly in permanent water bodies located in mountainous topography in the study area. These results should be taken into account when populations of this species are subjected to management and/or recovery programmes in arid areas.

  6. Habitat assessment ability of bumble-bees implies frequency-dependent selection on floral rewards and display size

    OpenAIRE

    Biernaskie, Jay M; Gegear, Robert J

    2007-01-01

    Foraging pollinators could visit hundreds of flowers in succession on mass-flowering plants, yet they often visit only a small number—potentially saving the plant from much self-pollination among its own flowers (geitonogamy). This study tests the hypothesis that bumble-bee (Bombus impatiens) residence on a particular plant depends on an assessment of that plant's reward value relative to the overall quality experienced in the habitat. In a controlled environment, naive bees were given experi...

  7. 基于人因学病房床单元的选择与优化%Optimization and selection of the bed units based on ergonomics

    Institute of Scientific and Technical Information of China (English)

    贺彩芳; 余园园; 陈丽莉; 詹健; 孙彩霞

    2015-01-01

    目的:针对传统病房床单元选择与设计过程中涉及人因学因素较少的现状,提出基于人因学的病房床单元的选择与设计的优化。方法基于人因学理论,从病房床单元物质客体本身具有的系统特性出发,采用全院普通病床一体化、电动自动控制病床、病床替代转运平车、床头柜加电子锁及取消热水瓶存放、个体化需求的处理等措施,以“满足人的需求”为主要解决目标,将“人”的因素考虑到硬件建设中,对病房床单元进行选择与设计的优化。结果医院的整体硬件设施得到质的提高,方便了患者与医护人员,实现了整体转运功能及术后患者的安全转运,确保了患者住院期间的安全。结论基于人因学病房床单元的选择与优化,提高了服务质量、工作效率及经济效益,使医院的管理更趋人性化、系统化、科学化。%Objective On account of the traditional unit selection and lack of ergonomics during the design process , the optimized and selection of the bed units were presented based on ergonomics . Methods Based on ergonomics theory and the systematic characteristic of wards units , the full integration of general hospital beds , electric automatic control of beds , alternative transport flatcar , bedside cabinets plus electronic locks and cancel thermos storage , and treatment were adopted to the individual needs , in order to achieve the goal of “meeting human needs” and take the “human” factor into the hardware construction .The ward bed unit selection and design was optimized .Results The overall quality of hospital hardware was improved, and it was convenient for the patients and medical staff .It achieved the overall transfer function and improved the safety of patients′transportation , so it ensured the safety of patients during hospitalization . Conclusions The optimization and selection based on ergonomics theory in ward bed can

  8. Multi-scale habitat selection in highly territorial bird species: Exploring the contribution of nest, territory and landscape levels to site choice in breeding rallids (Aves: Rallidae)

    Science.gov (United States)

    Jedlikowski, Jan; Chibowski, Piotr; Karasek, Tomasz; Brambilla, Mattia

    2016-05-01

    Habitat selection often involves choices made at different spatial scales, but the underlying mechanisms are still poorly understood, and studies that investigate the relative importance of individual scales are rare. We investigated the effect of three spatial scales (landscape, territory, nest-site) on the occurrence pattern of little crake Zapornia parva and water rail Rallus aquaticus at 74 ponds in the Masurian Lakeland, Poland. Habitat structure, food abundance and water chemical parameters were measured at nests and random points within landscape plots (from 300-m to 50-m radius), territory (14-m) and nest-site plots (3-m). Regression analyses suggested that the most relevant scale was territory level, followed by landscape, and finally by nest-site for both species. Variation partitioning confirmed this pattern for water rail, but also highlighted the importance of nest-site (the level explaining the highest share of unique variation) for little crake. The most important variables determining the occurrence of both species were water body fragmentation (landscape), vegetation density (territory) and water depth (at territory level for little crake, and at nest-site level for water rail). Finally, for both species multi-scale models including factors from different levels were more parsimonious than single-scale ones, i.e. habitat selection was likely a multi-scale process. The importance of particular spatial scales seemed more related to life-history traits than to the extent of the scales considered. In the case of our study species, the territory level was highly important likely because both rallids have to obtain all the resources they need (nest site, food and mates) in relatively small areas, the multi-purpose territories they defend.

  9. Recombinant protein purification using gradient-assisted simulated moving bed hydrophobic interaction chromatography. Part I: selection of chromatographic system and estimation of adsorption isotherms.

    Science.gov (United States)

    Palani, Sivakumar; Gueorguieva, Ludmila; Rinas, Ursula; Seidel-Morgenstern, Andreas; Jayaraman, Guhan

    2011-09-16

    The design of gradient simulated moving bed (SMB) chromatographic processes requires an appropriate selection of the chromatographic system followed by the determination of adsorption isotherm parameters in the relevant range of mobile phase conditions. The determination of these parameters can be quite difficult for recombinant target proteins present in complex protein mixtures. The first part of this work includes the estimation of adsorption isotherm parameters for streptokinase and a lumped impurity fraction present in an Escherichia coli cell lysate for a hydrophobic interaction chromatography (HIC) matrix. Perturbation experiments were carried out using a Butyl Sepharose matrix with purified recombinant protein on buffer equilibrated columns as well as with crude cell lysate saturated columns. The Henry constants estimated for streptokinase were found to exhibit in a wide range a linear dependence on the salt concentration in the mobile phase. These parameters were applied in subsequent investigations to design a simulated moving bed (SMB) process capable to purify in a continuous manner recombinant streptokinase from the E. coli cell lysate. PMID:21816402

  10. Foraging habits in a generalist predator: sex and age influence habitat selection and resource use among bottlenose dolphins (Tursiops truncatus)

    Science.gov (United States)

    Sam Rossman,; McCabe, Elizabeth Berens; Nelio B. Barros,; Hasand Gandhi,; Peggy H. Ostrom,; Stricker, Craig A.; Randall S. Wells,

    2015-01-01

    This study examines resource use (diet, habitat use, and trophic level) within and among demographic groups (males, females, and juveniles) of bottlenose dolphins (Tursiops truncatus). We analyzed the δ13C and δ15N values of 15 prey species constituting 84% of the species found in stomach contents. We used these data to establish a trophic enrichment factor (TEF) to inform dietary analysis using a Bayesian isotope mixing model. We document a TEF of 0‰ and 2.0‰ for δ13C and δ15N, respectively. The dietary results showed that all demographic groups relied heavily on low trophic level seagrass-associated prey. Bayesian standard ellipse areas (SEAb) were calculated to assess diversity in resource use. The SEAb of females was nearly four times larger than that of males indicating varied resource use, likely a consequence of small home ranges and habitat specialization. Juveniles possessed an intermediate SEAb, generally feeding at a lower trophic level compared to females, potentially an effect of natal philopatry and immature foraging skills. The small SEAb of males reflects a high degree of specialization on seagrass associated prey. Patterns in resource use by the demographic groups are likely linked to differences in the relative importance of social and ecological factors.

  11. Irradiation of the tumor bed alone after lumpectomy in selected patients with early stage breast cancer treated with breast conserving therapy

    International Nuclear Information System (INIS)

    Purpose: We present the initial findings of our in-house protocol treating the tumor bed alone after lumpectomy with low dose rate (LDR) interstitial brachytherapy in selected patients with early stage breast cancer treated with breast conserving therapy (BCT). Materials and Methods: Since 1/1/93, 50 women with early stage breast cancer were entered into a protocol of tumor bed irradiation alone using an interstitial LDR implant. Patients were eligible if their tumor was an infiltrating ductal carcinoma ≤ 3 cm in maximum diameter, pathologic margins were clear by at least 2 mm, the tumor did not contain an extensive intraductal component, the axilla was surgically staged with ≤ 3 nodes involved with cancer, and a postoperative mammogram was performed. Implants were positioned using a template guide delivering 50 Gy over 96 hours to the lumpectomy bed plus a 1-2 cm margin. Local control, cosmetic outcome, and complications were assessed. Results: Patients ranged in age from 40 to 84 years (median 65). The median tumor size was 10 mm (range, 1-25). Seventeen patients (34%) had well differentiated tumors, 22 (4%) had moderately differentiated tumors, and in 11 (22%) the tumor was poorly differentiated. Forty-five patients (90%) were node negative while 5 (10%) had 1-3 positive nodes. A total of 23 (46%) patients were placed on tamoxifen and 3 (6%) received adjuvant systemic chemotherapy. No patient was lost to follow-up. The median follow-up is 40 months (range 29-50). No patient has experienced a local, regional, or distant failure. One patient died from colorectal carcinoma with no evidence of recurrent breast cancer. Good-to-excellent cosmetic results have been observed in all 50 patients (median cosmetic follow-up 36 months). No patient has experienced significant sequelae related to their implant. Conclusions: Early results with treatment of the tumor bed alone with a LDR interstitial implant appear promising. Long-term follow-up of these patients will be

  12. Notes on the diet and habitat selection of the Sri Lankan Leopard Panthera pardus kotiya (Mammalia: Felidae in the central highlands of Sri Lanka

    Directory of Open Access Journals (Sweden)

    A.M. Kittle

    2014-08-01

    Full Text Available The endangered Sri Lankan Leopard Panthera pardus kotiya occupies the island’s highly fragmented central hills where data on its feeding ecology and habitat use is largely absent. This study’s objective was to investigate diet and resource selection of leopards here with a focus on the extent of potential interactions with humans in this heavily populated, largely unprotected landscape. Fecal sample analysis was undertaken to investigate diet and sign index counts and selectivity index analysis to determine habitat and landscape features important to fine scale leopard utilization. Results indicated that leopards in the central hills hunt a wide range of prey (at least 10 genera, including larger species where available (e.g., Sambar Rusa unicolor and smaller, more specialized prey (e.g., Porcupine Hystrix indica where necessary. No domestic species were recorded in scat analysis (N=35 despite the availability of dogs Canis familiaris, suggesting such predation may be atypical in Sri Lanka. Leopards use a range of landscapes within the region including established and regenerating forests, plantation lands (e.g., pine, eucalyptus, tea, and areas in close proximity to human settlement. At a fine scale, areas of dense undergrowth including tall grasslands were preferred to more open forest, as well as to Pine Pinus caribaea monocultures. Avoidance of humans may be influencing these patterns. This study has important implications as researchers and managers necessarily expand beyond focusing on protected areas toward integrated, landscape-level conservation strategies.

  13. Assessment of Fish Habitat, Water Quality, and Selected Contaminants in Streambed Sediments in Noyes Slough, Fairbanks, Alaska, 2001-2002

    Science.gov (United States)

    Kennedy, Ben W.; Whitman, Matthew S.; Burrows, Robert L.; Richmond, Sharon A.

    2004-01-01

    During 2001-2002, the U.S. Geological Survey sampled streambed sediment at 23 sites, measured water quality at 26 sites, and assessed fish habitat for the entire length of Noyes Slough, a 5.5-mile slough of the Chena River in Fairbanks, Alaska. These studies were undertaken to document the environmental condition of the slough and to provide information to the public for consideration in plans to improve environmental conditions of the waterway. The availability of physical habitat for fish in the slough does not appear to be limited, although some beaver dams and shallow water may restrict movement, particularly during low flow. Elevated water temperatures in summer and low dissolved-oxygen concentrations are the principle factors adversely affecting water quality in Noyes Slough. Increased flow mitigated poor water-quality conditions and reduced the number of possible fish barriers. Flow appears to be the most prominent mechanism shaping water quality and fish habitat in Noyes Slough. Streambed sediment samples collected at 23 sites in 2001 were analyzed for 24 trace elements. Arsenic, lead, and zinc were the only trace elements detected in concentrations that exceed probable effect levels for the protection of aquatic life. The background concentration for arsenic in Noyes Slough is naturally elevated because of significant concentrations of arsenic in local bedrock and ground water. Sources of the zinc and lead contamination are uncertain, however both lead and zinc are common urban contaminants. Streambed-sediment samples from 12 sites in 2002 were analyzed for organochlorine pesticides, polychlorinated biphenyls (PCBs), and semivolatile organic compounds (SVOCs). The concentration of bis(2-ethylhexyl)phthalate of 2,600 micrograms per kilogram (?g/kg) for one sample from the site above Aurora Drive approached the aquatic-life criterion of 2,650 ?g/kg. Low concentrations of p-cresol, chrysene, and fluoranthene were detected in most of the sediment samples. The

  14. A design and study of the effects of selectivity on binary separation in a four-zone simulated moving bed for systems with linear isotherms

    Directory of Open Access Journals (Sweden)

    M.A. Cremasco

    2003-06-01

    Full Text Available The simulated moving bed (SMB is potentially an economical method for the separation and purification of natural products because it is a continuous processes and can achieve higher productivity, higher product recovery, and higher purity than batch chromatographic processes. Despite the advantages of SMB, one of the challenges is to specify its zone flow rates and switching time. In this case it is possible to use the standing wave analysis. In this method, in a binary system, when certain concentration waves are confined to specific zones, high product purity and yield can be assured. Appropriate zone flow rates, zone lengths and step time are chosen to achieve standing waves. In this study the effects of selectivity on yield, throughput, solvent consumption, port switching time, and product purity for a binary system are analyzed. The results show that for a given selectivity the maximum throughput decreases with increasing yield, while solvent consumption and port switching time increase with increasing yield. To achieve the same purity and yield, a system with higher selectivity has a higher throughput and lower solvent consumption.

  15. High-resolution GPS tracking reveals habitat selection and the potential for long-distance seed dispersal by Madagascan flying foxes Pteropus rufus

    Directory of Open Access Journals (Sweden)

    Ryszard Oleksy

    2015-01-01

    Full Text Available Long-distance seed dispersal can be important for the regeneration of forested habitats, especially in regions where deforestation has been severe. Old World fruit bats (Pteropodidae have considerable potential for long-distance seed dispersal. We studied the movement patterns and feeding behaviour of the endemic Madagascan flying fox Pteropus rufus, in Berenty Reserve, southeast Madagascar. Between July and September 2012 (the dry season nine males and six females were tagged with customised GPS loggers which recorded fixes every 2.5 min between 18.00 and 06.00 h. The combined home range of all of the tagged bats during 86 nights exceeded 58,000 ha. Females had larger home ranges and core foraging areas and foraged over longer distances (average 28.1 km; median 26.7 km than males (average 15.4 km; median 9.5 km. Because the study was conducted during the gestation period, the increased energy requirements of females may explain their greater mean foraging area. Compositional analysis revealed that bats show strong preferences for overgrown sisal (Agave sisalana plantations (a mix of shrub, trees and sisal plants and remnant riverside forest patches. Sisal nectar and pollen were abundant food sources during the tracking period and this probably contributed to the selective use of overgrown sisal plantations. The bats also ate large quantities of figs (Ficus grevei during the study, and dispersed seeds of this important pioneer species. The bats flew at an average speed of 9.13 m/s, perhaps to optimise gliding performance. The study confirms that P. rufus has the potential to be a long-distance seed disperser, and is able to fly over a large area, often crossing cleared parts of its habitat. It potentially plays an important role in the regeneration of threatened forest habitats in this biodiversity hotspot.

  16. FORAGING BY THE STOPLIGHT-PARROTFISH SPARISOMA-VIRIDE .1. FOOD SELECTION IN DIFFERENT SOCIALLY DETERMINED HABITATS

    NARCIS (Netherlands)

    BRUGGEMANN, JH; VANOPPEN, MJH; BREEMAN, AM

    1994-01-01

    Food selection by the Caribbean stoplight parrotfish Sparisoma viride was investigated on a fringing coral reef of Bonaire, Netherlands Antilles. For different reef zones, the diet composition for each life phase was determined by description of randomly selected bites, and compared to the availabil

  17. Hiding in plain sight: A study on camouflage and habitat selection in a slow-moving desert herbivore

    OpenAIRE

    Nafus, MG; Germano, JM; Perry, JA; Todd, BD; Walsh, A.; Swaisgood, RR

    2015-01-01

    © The Author 2015. Published by Oxford University Press on behalf of the International Society for Behavioral Ecology. All rights reserved. Camouflage via animal coloration and patterning is a broadly important antipredator strategy. Behavioral decision making is an influential facet of many camouflage strategies; fitness benefits often are not realized unless an organism selects suitable backgrounds. Controlled experimental studies of behavioral strategies in selection of backgrounds conferr...

  18. 贺兰山牦牛冬春季的生境选择%Habitat selection of feral yak in winter and spring in the Helan Mountains, China

    Institute of Scientific and Technical Information of China (English)

    赵宠南; 苏云; 刘振生; 姚志诚; 张明明; 李志刚

    2012-01-01

    The yak (Bos grunniens) , sometimes called "the boat of the plateau" , is an endemic species of the Qirfghai-Tibet Plateau, famous for its resistance to cold and importance as a form of transport. The total number of adults may be close to 10,000 because the total population was estimated to be around 15,000 in 1995. Nevertheless, the species was listed as "Vulnerable" in the World Conservation Union's Red List of Threatened Animals because it is inferred that it has declined by over 30% over the last 30 years. Poaching, including commercial poaching for meat, has been the most serious threat to wild yaks. The species was listed on CITES Appendix I. Wild yaks have been protected in China since 1962, and are currently listed as a Class I protected animal, which means that they are fully protected by government law. In China, wild yaks are found in a number of large nature reserves, including the Arjin Shan, Chang Tang, Kekexili, Sanjiangyuan, and Yanchiwan Nature Reserves, although none of these reserves provide complete protection from habitat loss or occasional poaching. The yak population in the Helan Mountains is a reintroduced population from Qinghai-Tibet Plateau, and is only distributed in the Halawu Valleys and the surrounding areas, in the Helan Mountain Reserve in Inner Mongolia. Becausetheir habitat selection had not been previously studied, we conducted surveys from December 2009 to January 2010 and from April to May 2010 to study yak habitat selection in winter and spring. Twenty line transects were established along seven valleys. We identified a total number of 103 used plots in winter and 129 in spring. To provide comparison plots for the analysis of habitat selections, we surveyed 188 randomly placed plots in winter and 207 randomly placed plots in spring by systematically placing transects in areas with no obvious evidence of yak use. Data on 18 topographic and biological variables were collected in each plot. In winter, yaks preferred montane

  19. 2001-2006年黄河三角洲鹤类生境选择分析%Habitat Selection of Cranes in Yellow River Delta from 2001 to 2006

    Institute of Scientific and Technical Information of China (English)

    李若楠; 单凯

    2012-01-01

    把鹤类及其生境作为整体研究对象,利用Vanderploeg选择系数评估鹤对生境的选择性,利用Neu方法通过可获得性系数与可利用性系数比较评估鹤对生境类型的偏好,研究了2001-2006年黄河三角洲鹤类与生境的对应关系.结果表明:芦苇沼泽是鹤类偏好性选择的生境,为白头鹤、白枕鹤、灰鹤优先选择的生境.潮间带是鹤类回避性选择生境,为白鹤和丹顶鹤优先选择的生境.河道、养殖池、农田和草地4类生境受人为活动的影响较重,鹤类利用较低,年度间利用情况变化大.当生境类型发生改变时,鹤类会自主选择更为适宜的生境并导致对其它生境的选择性改变.%A survey was conducted to study the corresponding relationship between cranes and habitats during 2001 -2006 in Yellow River Delta. Vanderploeg selection coefficient was applied to evaluate the habitat selection of cranes, and availability coefficient and utilization coefficient obtained by the Neu method were used to compare the habitat preferences of cranes. Results show that the cranes have a preference for need swamp, and it is a favorite habitat for Hooded Crane, White-naped Crane and Common Crane. However, intertidal zone is a favorite habitat for Siberian Crane and Red-crowned Crane. River channel , culture pond, farmland and grassland affected heavily by human activities are rarely selected by the cranes. There are significant differences in habitat selection and preference selection for different species of cranes between different years. When habitats change, the cranes will select their suitable habitats, which results in a change in habitat selection coefficient.

  20. Comparative analysis of different survey methods for monitoring fish assemblages in coastal habitats

    Science.gov (United States)

    Baker, Duncan G.L.; McIver, Reba; Schmidt, Allison L.; Thériault, Marie-Hélène; Boudreau, Monica; Courtenay, Simon C.; Lotze, Heike K.

    2016-01-01

    Coastal ecosystems are among the most productive yet increasingly threatened marine ecosystems worldwide. Particularly vegetated habitats, such as eelgrass (Zostera marina) beds, play important roles in providing key spawning, nursery and foraging habitats for a wide range of fauna. To properly assess changes in coastal ecosystems and manage these critical habitats, it is essential to develop sound monitoring programs for foundation species and associated assemblages. Several survey methods exist, thus understanding how different methods perform is important for survey selection. We compared two common methods for surveying macrofaunal assemblages: beach seine netting and underwater visual census (UVC). We also tested whether assemblages in shallow nearshore habitats commonly sampled by beach seines are similar to those of nearby eelgrass beds often sampled by UVC. Among five estuaries along the Southern Gulf of St. Lawrence, Canada, our results suggest that the two survey methods yield comparable results for species richness, diversity and evenness, yet beach seines yield significantly higher abundance and different species composition. However, sampling nearshore assemblages does not represent those in eelgrass beds despite considerable overlap and close proximity. These results have important implications for how and where macrofaunal assemblages are monitored in coastal ecosystems. Ideally, multiple survey methods and locations should be combined to complement each other in assessing the entire assemblage and full range of changes in coastal ecosystems, thereby better informing coastal zone management. PMID:27018396

  1. Comparative analysis of different survey methods for monitoring fish assemblages in coastal habitats.

    Science.gov (United States)

    Baker, Duncan G L; Eddy, Tyler D; McIver, Reba; Schmidt, Allison L; Thériault, Marie-Hélène; Boudreau, Monica; Courtenay, Simon C; Lotze, Heike K

    2016-01-01

    Coastal ecosystems are among the most productive yet increasingly threatened marine ecosystems worldwide. Particularly vegetated habitats, such as eelgrass (Zostera marina) beds, play important roles in providing key spawning, nursery and foraging habitats for a wide range of fauna. To properly assess changes in coastal ecosystems and manage these critical habitats, it is essential to develop sound monitoring programs for foundation species and associated assemblages. Several survey methods exist, thus understanding how different methods perform is important for survey selection. We compared two common methods for surveying macrofaunal assemblages: beach seine netting and underwater visual census (UVC). We also tested whether assemblages in shallow nearshore habitats commonly sampled by beach seines are similar to those of nearby eelgrass beds often sampled by UVC. Among five estuaries along the Southern Gulf of St. Lawrence, Canada, our results suggest that the two survey methods yield comparable results for species richness, diversity and evenness, yet beach seines yield significantly higher abundance and different species composition. However, sampling nearshore assemblages does not represent those in eelgrass beds despite considerable overlap and close proximity. These results have important implications for how and where macrofaunal assemblages are monitored in coastal ecosystems. Ideally, multiple survey methods and locations should be combined to complement each other in assessing the entire assemblage and full range of changes in coastal ecosystems, thereby better informing coastal zone management.

  2. Space-Use Patterns of the Asiatic Wild Ass (Equus hemionus: Complementary Insights from Displacement, Recursion Movement and Habitat Selection Analyses.

    Directory of Open Access Journals (Sweden)

    Nina Giotto

    Full Text Available The way in which animals move and use the landscape is influenced by the spatial distribution of resources, and is of importance when considering species conservation. We aimed at exploring how landscape-related factors affect a large herbivore's space-use patterns by using a combined approach, integrating movement (displacement and recursions and habitat selection analyses. We studied the endangered Asiatic wild ass (Equus hemionus in the Negev Desert, Israel, using GPS monitoring and direct observation. We found that the main landscape-related factors affecting the species' space-use patterns, on a daily and seasonal basis, were vegetation cover, water sources and topography. Two main habitat types were selected: high-elevation sites during the day (specific microclimate: windy on warm summer days and streambed surroundings during the night (coupled with high vegetation when the animals were active in summer. Distribution of recursion times (duration between visits revealed a 24-hour periodicity, a pattern that could be widespread among large herbivores. Characterizing frequently revisited sites suggested that recursion movements were mainly driven by a few landscape features (water sources, vegetation patches, high-elevation points, but also by social factors, such as territoriality, which should be further explored. This study provided complementary insights into the space-use patterns of E. hemionus. Understanding of the species' space-use patterns, at both large and fine spatial scale, is required for developing appropriate conservation protocols. Our approach could be further applied for studying the space-use patterns of other species in heterogeneous landscapes.

  3. Habitat Suitability Index Models: Smallmouth Buffalo

    Science.gov (United States)

    Edwards, Elizabeth A.; Twomey, Katie

    1982-01-01

    This is one of a series of publications that provide information on the habitat requirements of selected fish and wildlife species. Literature describing the relationship between habitat variables related to life requisites and habitat suitability for the Smallmouth buffalo (Ictiobus bubalus) are synthesized. These data are subsequently used to develop Habitat Suitability (HIS) models. The HSI models are designed to provide information that can be used in impact assessment and habitat management.

  4. 1999 resource assessment of selected Tertiary coal beds and zones in the Northern Rocky Mountains and Great Plains region

    Science.gov (United States)

    ,

    1999-01-01

    The USGS has assessed resources of selected coal of the Fort Union Formation and equivalent units in the Northern Rocky Mountains and Great Plains region. The assessment focused on coal in the Powder River, Williston, Hanna-Carbon, and Greater Green River basins most likely to be utilized in the next few decades. In other basins in the region Tertiary coal resources are summarized but not assessed. Disc 1, in PDF files, includes results of the assessment and chapters on coal geology, quantity and quality, and land use and ownership. Disc 2 provides GIS files for land use and ownership maps and geologic maps, and basic GIS data for the assessed basins. ArcView shapefiles, PDF files for cross sections and TIFF files are included along with ArcView Datapublisher software for Windows-based computer systems.

  5. Selection of an adhesive phenotype of Streptococcus salivarius subsp. thermophilus for use in fixed-bed reactors.

    Science.gov (United States)

    Ragout, A; Siñeriz, F; Kaul, R; Guoqiang, D; Mattiasson, B

    1996-09-01

    Streptococcus salivarius subsp. thermophilus was cultivated in a chemostat in order to obtain an adhesive phenotype of this strain. When the system was operated at low dilution rates (D biomass productivity (P = 4.1 g1(-1) h-1). On the other hand, when the culture was grown at dilution rates faster than 0.2 h-1, only the free suspended cells were present in the culture broth, and were washed out at velocities of about 1.0 h-1. The biomass productivity was consequently lower (P = 1.33 g1(-1) h-1) than in the previous case. The selected adhesive phenotype was grown on different glass beads and the possibility of lactate fermentation in a continuous and semicontinuous mode was demonstrated.

  6. Use of stress-hormone levels and habitat selection to assess functional connectivity of a landscape for an amphibian.

    Science.gov (United States)

    Janin, Agnès; Léna, Jean-Paul; Deblois, Sandrine; Joly, Pierre

    2012-10-01

    The influence of landscape matrix on functional connectivity has been clearly established. Now methods to assess the effects of different land uses on species' movements are needed because current methods are often biased. The use of physiological parameters as indicators of the level of resistance to animal movement associated with different land uses (i.e., matrix resistance) could provide estimates of energetic costs and risks to animals migrating through the matrix. To assess whether corticosterone levels indicate matrix resistance, we conducted experiments on substrate choice and measured levels of corticosterone before and after exposure of toads (Bufo bufo) to 3 common substrates (ploughed soil, meadow, and forest litter). We expected matrix resistance and hormone levels to increase from forest litter (habitat of the toad) to meadows to ploughed soil. Adult toads had higher corticosterone levels on ploughed soil than on forest litter or meadow substrates. Hormone levels did not differ between forest litter and meadow. Toads avoided moving onto ploughed soil. Corticosterone levels in juvenile toads were not related to substrate type; however, hormone levels decreased as humidity increased. Juveniles, unlike adults, did not avoid moving over ploughed soil. The difference in responses between adult and juvenile toads may have been due to differences in experimental design (for juveniles, entire body used to measure corticosterone concentration; for adults, saliva alone); differences in the scale of sensory perception of the substrate (juveniles are much smaller than adults); or differences in cognitive processes between adult and juvenile toads. Adults probably had experience with different substrate types, whereas juveniles first emerging from the water probably did not. As a consequence, arable lands could act as ecological traps for juvenile toads. PMID:22891816

  7. Vascular Reactivity Profile of Novel KCa 3.1-Selective Positive-Gating Modulators in the Coronary Vascular Bed.

    Science.gov (United States)

    Oliván-Viguera, Aida; Valero, Marta Sofía; Pinilla, Estéfano; Amor, Sara; García-Villalón, Ángel Luis; Coleman, Nichole; Laría, Celia; Calvín-Tienza, Víctor; García-Otín, Ángel-Luis; Fernández-Fernández, José M; Murillo, M Divina; Gálvez, José A; Díaz-de-Villegas, María D; Badorrey, Ramón; Simonsen, Ulf; Rivera, Luis; Wulff, Heike; Köhler, Ralf

    2016-08-01

    Opening of intermediate-conductance calcium-activated potassium channels (KC a 3.1) produces membrane hyperpolarization in the vascular endothelium. Here, we studied the ability of two new KC a 3.1-selective positive-gating modulators, SKA-111 and SKA-121, to (1) evoke porcine endothelial cell KC a 3.1 membrane hyperpolarization, (2) induce endothelium-dependent and, particularly, endothelium-derived hyperpolarization (EDH)-type relaxation in porcine coronary arteries (PCA) and (3) influence coronary artery tone in isolated rat hearts. In whole-cell patch-clamp experiments on endothelial cells of PCA (PCAEC), KC a currents evoked by bradykinin (BK) were potentiated ≈7-fold by either SKA-111 or SKA-121 (both at 1 μM) and were blocked by a KC a 3.1 blocker, TRAM-34. In membrane potential measurements, SKA-111 and SKA-121 augmented bradykinin-induced hyperpolarization. Isometric tension measurements in large- and small-calibre PCA showed that SKA-111 and SKA-121 potentiated endothelium-dependent relaxation with intact NO synthesis and EDH-type relaxation to BK by ≈2-fold. Potentiation of the BK response was prevented by KC a 3.1 inhibition. In Langendorff-perfused rat hearts, SKA-111 potentiated coronary vasodilation elicited by BK. In conclusion, our data show that positive-gating modulation of KC a 3.1 channels improves BK-induced membrane hyperpolarization and endothelium-dependent relaxation in small and large PCA as well as in the coronary circulation of rats. Positive-gating modulators of KC a 3.1 could be therapeutically useful to improve coronary blood flow and counteract impaired coronary endothelial dysfunction in cardiovascular disease. PMID:26821335

  8. Initial Results from a Study of Climatic Changes and the Effect on Wild Sheep Habitat in Selected Study Areas of Alaska

    Science.gov (United States)

    Pfeifer, Edwin; Ruhlman, Jana; Middleton, Barry; Dye, Dennis; Acosta, Alex

    2010-01-01

    data bases relating to Dall sheep habitats in selected study areas. Alaska's sheep habitats are typified by long, narrow bands of mountainous uplifts generally arrayed west-to-east, and perpendicular to prevailing south-to-north weather-front movements. Classic Dall sheep habitat occurs on snow-shadowed slopes within these narrow mountainous habitats. On the basis of these data, we offer an explanatory hypothesis relating Dall sheep welfare to weather and climate-influenced nutrition and a monitoring scheme, which should produce data sufficient to test the robustness of this hypothesis. If correlated with population changes, the methods used in our comparative observations may provide long-term monitoring tools for wildlife managers and be applicable in other widely-dispersed wild sheep habitats. If no significant correlations emerge from our modeling exercises, the notion that wild sheep are a sufficiently sensitive species to be seen as an indicator species will have to be reexamined.

  9. 1999 resource assessment of selected tertiary coal beds and zones in the northern rocky mountains and Great Plains region. Version 1.1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-01

    The US Geological Survey has assessed resources of selected coal of the Tertiary Fort Union Formation and equivalent units in the Northern Rocky Mountains and Great Plains region. The assessment focused on those selected coal beds and zones in the Powder River, Williston, Hanna-Carbon, and Greater Green River Basins most likely to be utilised in the next few decades. In other basins tertiary coal resources are summarized but not assessed. Coal resources in the assessed basins are low in sulfur, ash and trace elements of environmental concern. Coal produced from the Wyodak-Anderson coal zone in the Powder River Basin has one of the lowest values of SO{sub 2}/mmBtu (about 1.2 lbs) of any coal in the US. This coal zone contains an estimated resource of 550 billion short tons in the Powder River Basin. Disc 1 of this CD-ROM set, in PDF (Portable Document Format), contains the results of the assessment and chapters on coal geology, occurrence, distribution, quantity and quality accompanied by maps, cross sections, tables, graphs, figures, and photographs; land use and land ownership maps are also included. The various parts of the text, maps, cross sections, figures, and graphs are linked and views can be planned and zoomed. Disc 2 contains interactive GIS files of land use and ownership maps, geologic maps, interpretive maps and cross sections, basic GIS data, and metadata for maps in the assessed coal basins. PDFs of cross sections are included. The disc allows users to: 1) access, analyze and query the data and generate derivative digital products; and 2) download copies of digital products and data. The disc contains ArcView shapefiles and PDF and TIFF files. ArcView Data Publisher software is provided for Windows-based computer systems. The maps, cross sections, data, and metadata are linked and views can be panned and zoomed.

  10. Oribatid communities and heavy metal bioaccumulation in selected species associated with lichens in a heavily contaminated habitat.

    Science.gov (United States)

    Skubała, Piotr; Rola, Kaja; Osyczka, Piotr

    2016-05-01

    The study examines oribatid communities and heavy metal bioaccumulation in selected species associated with different microhabitats of a post-smelting dump, i.e. three lichen species of Cladonia with various growth forms and the slag substrate. The abundance of oribatids collected from the substrate was significantly lower than observed in lichen thalli. The morphology and chemical properties of lichens, and to some extent varying concentrations of heavy metals in thalli, are probably responsible for significant differences in oribatid communities inhabiting different Cladonia species. Some oribatids demonstrate the ability to accumulate zinc and cadmium with unusual efficiency, whereas lead is the most effectively regulated element by all species. A positive correlation was found between Zn content in all studied oribatids and their microhabitats. Oribatids exploring different food resources, i.e. fungivorous and non-fungivorous grazers, show considerable differences in bioconcentrations of certain elements. PMID:26810668

  11. RELATING WEIGHT AND COUNT DISTRIBUTIONS OF STREAM BED GRAVEL

    Science.gov (United States)

    The size distribution of particles in a stream bed reflects the stream hydrology as well as its physical and chemical water quality characteristics. In environmental assessments, gravel distribution determines habitat quality for aquatic insects and stream suitability for spawnin...

  12. Effect of Infection Duration on Habitat Selection and Morphology of Adult Echinostoma caproni (Digenea: Echinostomatidae) in ICR Mice.

    Science.gov (United States)

    Platt, Thomas R; Zelmer, Derek A

    2016-02-01

    The course of infection of Echinostoma caproni was followed in female ICR mice, a permissive laboratory host, from infection to natural termination. Twenty-one mice were infected with 20 metacercariae via oral intubation and housed 3 per cage. Three mice from a randomly selected cage were necropsied at 1 mo intervals. A second group of 15 mice was infected approximately 1 yr later to replace mice negative at necropsy in the first group. Mice in the second group were examined weekly for the presence of eggs in the feces. Mice negative for eggs on consecutive days were killed and necropsied. The location of individual worms and worm clusters were located in 20 segments of the small intestine. Adult worms were killed and fixed in hot formalin, stained, and prepared as whole mounts. Standard measurements were taken using a compound microscope fitted with an ocular micrometer. The infection spontaneously resolved in 10 mice from 7 to 32 wk PI, indicating the host response is highly variable and extending the maximum recorded length of E. caproni infections in ICR mice to 31 wk. A moribund worm was found in the feces of an animal that continued to pass eggs for an additional 2 mo indicating individual variation in worm responses. Worms located preferentially in the ileum (segments 11-13) during the first 3 mo of the infection but shifted to the jejunum (segments 8-9) during weeks 4-6. Morphologically, worms of different ages clustered together in multivariate space, with substantial overlap between the 3- and 4-mo-old infrapopulations and between the 5- and 6-mo-old infrapopulations. Muscular structures increased in size throughout the experiment, while the gonads increased in size for the first 3 mo and then declined during the last 3 mo. The relationship between E. caproni and ICR mice is more nuanced than previously reported. The reduction in gonad size and the shift from the ileum to the jejunum in the last 3 mo likely are related. These changes might be attributable

  13. The Research Progress of Terrestrial Wildlife Habitat Selection from Spatial Scale%从空间尺度论述陆生野生动物生境选择研究进展

    Institute of Scientific and Technical Information of China (English)

    郑彦超; 吴昊; 刘善辉

    2015-01-01

    指出了生境是动物生存和繁衍的重要场所,生境的质量及其可利用程度是决定动物种群生死存亡的关键因素。因此,研究动物的生境利用特点成为生物保护学研究的热点。综述了不同空间尺度上陆生野生动物生境选择研究的概况,以期对今后开展生境利用研究工作时在方法的选取方面提供借鉴和指导。%The habitat is an important place for animals'survival and reproduction ,whose quality and extent of availability are key factors in determining the survival or extinction of animals . Therefore , the study on characteristics of habitat selection has become a research hotspot in the field of conservation biology .The article gives an overview of the studies of terrestrial wildlife's habitat selection on various spatial scales ,which aims to provide some references and guidance for the selection of research methods in habitat utilization studies in the future .

  14. The gut microbiome of the sea urchin, Lytechinus variegatus, from its natural habitat demonstrates selective attributes of microbial taxa and predictive metabolic profiles.

    Science.gov (United States)

    Hakim, Joseph A; Koo, Hyunmin; Kumar, Ranjit; Lefkowitz, Elliot J; Morrow, Casey D; Powell, Mickie L; Watts, Stephen A; Bej, Asim K

    2016-09-01

    In this paper, we describe the microbial composition and their predictive metabolic profile in the sea urchin Lytechinus variegatus gut ecosystem along with samples from its habitat by using NextGen amplicon sequencing and downstream bioinformatics analyses. The microbial communities of the gut tissue revealed a near-exclusive abundance of Campylobacteraceae, whereas the pharynx tissue consisted of Tenericutes, followed by Gamma-, Alpha- and Epsilonproteobacteria at approximately equal capacities. The gut digesta and egested fecal pellets exhibited a microbial profile comprised of Gammaproteobacteria, mainly Vibrio, and Bacteroidetes. Both the seagrass and surrounding sea water revealed Alpha- and Betaproteobacteria. Bray-Curtis distances of microbial communities indicated a clustering profile with low intrasample variation. Predictive metagenomics performed on the microbial communities revealed that the gut tissue had high relative abundances of metabolisms assigned to the KEGG-Level-2 designation of energy metabolisms compared to the gut digesta, which had higher carbohydrate, amino acid and lipid metabolisms. Overall, the results of this study elaborate the spatial distribution of microbial communities in the gut ecosystem of L. variegatus, and specifically a selective attribute for Campylobacteraceae in the gut tissue. Also, the predictive functional significance of bacterial communities in uniquely compartmentalized gut ecosystems of L. variegatus has been described. PMID:27368709

  15. River Bed Sediment Classification Using ADCP

    Science.gov (United States)

    Description of physical aquatic habitat in rivers often includes data describing distributions of water depth, velocity and bed material type. Water depth and velocity in streams deeper than about 1 m may be continuously mapped using an acoustic Doppler current profiler from a moving boat. Herein ...

  16. Camouflage and individual variation in shore crabs (Carcinus maenas) from different habitats.

    Science.gov (United States)

    Stevens, Martin; Lown, Alice E; Wood, Louisa E

    2014-01-01

    Camouflage is widespread throughout the natural world and conceals animals from predators in a vast range of habitats. Because successful camouflage usually involves matching aspects of the background environment, species and populations should evolve appearances tuned to their local habitat, termed phenotype-environment associations. However, although this has been studied in various species, little work has objectively quantified the appearances of camouflaged animals from different habitats, or related this to factors such as ontogeny and individual variation. Here, we tested for phenotype-environment associations in the common shore crab (Carcinus maenas), a species highly variable in appearance and found in a wide range of habitats. We used field surveys and digital image analysis of the colors and patterns of crabs found in four locations around Cornwall in the UK to quantify how individuals vary with habitat (predominantly rockpool, mussel bed, and mudflat). We find that individuals from sites comprising different backgrounds show substantial differences in several aspects of color and pattern, and that this is also dependent on life stage (adult or juvenile). Furthermore, the level of individual variation is dependent on site and life stage, with juvenile crabs often more variable than adults, and individuals from more homogenous habitats less diverse. Ours is the most comprehensive study to date exploring phenotype-environment associations for camouflage and individual variation in a species, and we discuss the implications of our results in terms of the mechanisms and selection pressures that may drive this.

  17. Selective uptake of major and trace elements in Erica andevalensis, an endemic species to extreme habitats in the Iberian Pyrite Belt

    Institute of Scientific and Technical Information of China (English)

    Fabrizio Monaci; Eduardo O. Leidi; Maria Dolores Mingorance; Benito Valdés; Sabina Rossini Oliva; Roberto Bargagli

    2011-01-01

    To assess the ecophysiological traits and the phytoremediation potential of the endemic heather Erica andevalensis, we determined the concentrations of major and trace elements in different plant parts and in rizosphere soils from Riotinto mining district (Huelva, Spain).The results showed that E.andevalensis may grow on substrates with very high As, Cu, Fe and Pb concentrations (up to 4114, 1050, 71900 and 15614 μg/g dry weight, respectively), very low availability of macro- and micronutrients and with pH values ranging from 3.3 to 4.9.In these harsh edaphic conditions E.andevalensis selectively absorbed and translocated essential nutrients and excludes potentially phytotoxic elements, which were accumulated in the root epidermis.The concentrations of major and trace elements in E.andevalensis aerial parts from the Riotinto mining district were in the normal range for plants; likewise other Erica species it accumulated Mn and only in a very polluted site we measured leaf concentrations of As and Pb within the excessive or toxic limits for plants.Differently from previous studies, which emphasized the soil pH and bioavailability of phytotoxic elements as the main stress factors, this study showed that in the Riotinto region, E.andevalensis can tolerate wide range of pH and toxic element concentrations; the harshest environments colonized by monospecific patches of this species were characterized above all by very low availability of nutrients.The extraordinary capability to adapt to these extreme habitats made E.andevalensis a priority species to promote the phytostabilization and the development of a self-sustaining vegetative cover on Riotinto mine tailings.

  18. Separating natural responses from experimental artefacts: habitat selection by a diadromous fish species using odours from conspecifics and natural stream water.

    Science.gov (United States)

    Hale, Robin; Swearer, Stephen E; Downes, Barbara J

    2009-03-01

    Animals use sensory stimuli to assess and select habitats, mates and food as well as to communicate with other individuals. One way they do this is to use olfaction, whereby they identify and respond to chemical cues. All organisms release odours, which mix with other chemical substances and ambient environmental conditions. The result is that animals are frequently immersed in a complex, highly dynamic sensory environment where they must identify and respond to only some of the potential stimuli they encounter in the face of significant levels of background noise. Understanding how organisms respond to different chemical cues is therefore dependent on knowing how these responses might be influenced by potential interactions with other stimuli. To test this, we examined whether the diadromous fish Galaxias maculatus was attracted to conspecific odours and whether this response differed when cues were offered in an artificial environment lacking other potential chemical stimuli (tap water) or a more natural background environment (stream water). We found that (1) fish responded to both natural stream water odours and those from conspecifics but the response to the latter was stronger; (2) the attraction to conspecific odours was stronger in tap water than in stream water, which indicates the importance of these odours may be overestimated when they are offered in artificial media. We also conducted a brief literature review, which confirmed that artificial media are commonly used in experiments and that the background environment is often not considered. Our results show that future research testing the responses of organisms to auditory, olfactory and visual cues should carefully consider the context in which cues are presented. Without doing so, such studies may inaccurately assess the importance of sensory cues in natural situations in the wild. PMID:19139923

  19. Between a rock and a hard place: habitat selection in female-calf humpback whale (Megaptera novaeangliae Pairs on the Hawaiian breeding grounds.

    Directory of Open Access Journals (Sweden)

    Rachel Cartwright

    Full Text Available The Au'au Channel between the islands of Maui and Lanai, Hawaii comprises critical breeding habitat for humpback whales (Megaptera novaeangliae of the Central North Pacific stock. However, like many regions where marine mega-fauna gather, these waters are also the focus of a flourishing local eco-tourism and whale watching industry. Our aim was to establish current trends in habitat preference in female-calf humpback whale pairs within this region, focusing specifically on the busy, eastern portions of the channel. We used an equally-spaced zigzag transect survey design, compiled our results in a GIS model to identify spatial trends and calculated Neu's Indices to quantify levels of habitat use. Our study revealed that while mysticete female-calf pairs on breeding grounds typically favor shallow, inshore waters, female-calf pairs in the Au'au Channel avoided shallow waters (<20 m and regions within 2 km of the shoreline. Preferred regions for female-calf pairs comprised water depths between 40-60 m, regions of rugged bottom topography and regions that lay between 4 and 6 km from a small boat harbor (Lahaina Harbor that fell within the study area. In contrast to other humpback whale breeding grounds, there was only minimal evidence of typical patterns of stratification or segregation according to group composition. A review of habitat use by maternal females across Hawaiian waters indicates that maternal habitat choice varies between localities within the Hawaiian Islands, suggesting that maternal females alter their use of habitat according to locally varying pressures. This ability to respond to varying environments may be the key that allows wildlife species to persist in regions where human activity and critical habitat overlap.

  20. Aquatic Habitat Bottom Classification Using ADCP

    Science.gov (United States)

    Description of physical aquatic habitat often includes data describing distributions of water depth, velocity and bed material type. Water depth and velocity in streams deeper than about 1 m may be continuously mapped using an acoustic Doppler current profiler from a moving boat. Herein we examine...

  1. Froude Number is the Single Most Important Hydraulic Parameter for Salmonid Spawning Habitat.

    Science.gov (United States)

    Gillies, E.; Moir, H. J.

    2015-12-01

    Many gravel-bed rivers exhibit historic straightening or embanking, reducing river complexity and the available habitat for key species such as salmon. A defensible method for predicting salmonid spawning habitat is an important tool for anyone engaged in assessing a river restoration. Most empirical methods to predict spawning habitat use lookup tables of depth, velocity and substrate. However, natural site selection is different: salmon must pick a location where they can successfully build a redd, and where eggs have a sufficient survival rate. Also, using dimensional variables, such as depth and velocity, is problematic: spawning occurs in rivers of differing size, depth and velocity range. Non-dimensional variables have proven useful in other branches of fluid dynamics, and instream habitat is no different. Empirical river data has a high correlation between observed salmon redds and Froude number, without insight into why. Here we present a physics based model of spawning and bedform evolution, which shows that Froude number is indeed a rational choice for characterizing the bedform, substrate, and flow necessary for spawning. It is familiar for Froude to characterize surface waves, but Froude also characterizes longitudinal bedform in a mobile bed river. We postulate that these bedforms and their hydraulics perform two roles in salmonid spawning: allowing transport of clasts during redd building, and oxygenating eggs. We present an example of this Froude number and substrate based habitat characterization on a Scottish river for which we have detailed topography at several stages during river restoration and subsequent evolution of natural processes. We show changes to the channel Froude regime as a result of natural process and validate habitat predictions against redds observed during 2014 and 2015 spawning seasons, also relating this data to the Froude regime in other, nearby, rivers. We discuss the use of the Froude spectrum in providing an indicator of

  2. GeoLab—A habitat-based laboratory for preliminary examination of geological samples

    Science.gov (United States)

    Evans, Cynthia A.; Calaway, Michael J.; Sue Bell, Mary; Young, Kelsey E.

    2013-10-01

    GeoLab is a prototype geological laboratory designed for deployment and testing during NASA's analog demonstrations. Scientists at NASA's Johnson Space Center (JSC) built GeoLab as part of a technology project to support the development of science operational concepts for future planetary surface missions. It was integrated into NASA's Habitat Demonstration Unit 1 - Pressurized Excursion Module (HDU1-PEM), a first generation exploration habitat test bed. As a test bed, GeoLab provides a high fidelity working space for crewmembers to perform preliminary examination and characterization of geologic samples. The GeoLab concept builds from the hardware and cleanroom protocols used in JSC's Astromaterials Sample Curation laboratories. The main hardware component of the GeoLab is a custom-built glovebox, constructed from stainless steel and polycarbonate, and built to provide a positive pressure nitrogen environment. The glovebox is mounted onto the habitat's structural ribs; the unique shape (trapezoidal prism) fits within a pie-shaped section of the cylindrical habitat. A key innovation of GeoLab is the mechanism for transferring samples into the glovebox: three antechambers (airlocks) that pass through the shell of the habitat. These antechambers allow geologic samples to enter and exit the main glovebox chamber directly from (and to) the outside, thereby controlling contamination from inside the habitat. The glovebox is configured to include imaging systems, instrumentation, and computer controls. The first field trials tested a simple configuration including a microscope, a commercially available handheld X-ray Fluorescence instrument, network cameras, and simple sample handling tools inside the glovebox. We present results from the initial field trials of GeoLab during the 2010 Desert Research and Technology Studies (Desert RATS) planetary analog test near Flagstaff, AZ. These field tests examined the general operations of the GeoLab hardware and the crew

  3. Determination of the effects of fine-grained sediment and other limiting variables on trout habitat for selected streams in Wisconsin

    Science.gov (United States)

    Scudder, Barbara C.; Selbig, J.W.; Waschbusch, R.J.

    2000-01-01

    Two Habitat Suitability Index (HSI) models, developed by the U.S. Fish and Wildlife Service, were used to evaluate the effects of fine-grained (less than 2 millimeters) sediment on brook trout (Salvelinusfontinalis, Mitchill) and brown trout (Salmo trutta, Linnaeus) in 11 streams in west-central and southwestern Wisconsin. Our results indicated that fine-grained sediment limited brook trout habitat in 8 of 11 streams and brown trout habitat in only one stream. Lack of winter and escape cover for fry was the primary limiting variable for brown trout at 61 percent of the sites, and this factor also limited brook trout at several stations. Pool area or quality, in stream cover, streambank vegetation for erosion control, minimum flow, thalweg depth maximum, water temperature, spawning substrate, riffle dominant substrate, and dissolved oxygen also were limiting to trout in the study streams. Brook trout appeared to be more sensitive to the effects of fine-grained sediment than brown trout. The models for brook trout and brown trout appeared to be useful and objective screening tools for identifying variables limiting trout habitat in these streams. The models predicted that reduction in the amount of fine-grained sediment would improve brook trout habitat. These models may be valuable for establishing instream sediment-reduction goals; however, the decrease in sediment delivery needed to meet these goals cannot be estimated without quantitative data on land use practices and their effects on sediment delivery and retention by streams.

  4. Habitat cascades: the conceptual context and global relevance of facilitation cascades via habitat formation and modification.

    Science.gov (United States)

    Thomsen, Mads S; Wernberg, Thomas; Altieri, Andrew; Tuya, Fernando; Gulbransen, Dana; McGlathery, Karen J; Holmer, Marianne; Silliman, Brian R

    2010-08-01

    The importance of positive interactions is increasingly acknowledged in contemporary ecology. Most research has focused on direct positive effects of one species on another. However, there is recent evidence that indirect positive effects in the form of facilitation cascades can also structure species abundances and biodiversity. Here we conceptualize a specific type of facilitation cascade-the habitat cascade. The habitat cascade is defined as indirect positive effects on focal organisms mediated by successive facilitation in the form of biogenic formation or modification of habitat. Based on a literature review, we demonstrate that habitat cascades are a general phenomenon that enhances species abundance and diversity in forests, salt marshes, seagrass meadows, and seaweed beds. Habitat cascades are characterized by a hierarchy of facilitative interactions in which a basal habitat former (typically a large primary producer, e.g., a tree) creates living space for an intermediate habitat former (e.g., an epiphyte) that in turn creates living space for the focal organisms (e.g., spiders, beetles, and mites). We then present new data on a habitat cascade common to soft-bottom estuaries in which a relatively small invertebrate provides basal habitat for larger intermediate seaweeds that, in turn, generate habitat for focal invertebrates and epiphytes. We propose that indirect positive effects on focal organisms will be strongest when the intermediate habitat former is larger and different in form and function from the basal habitat former. We also discuss how humans create, modify, and destroy habitat cascades via global habitat destruction, climatic change, over-harvesting, pollution, or transfer of invasive species. Finally, we outline future directions for research that will lead to a better understanding of habitat cascades. PMID:21558196

  5. Habitat use and diet selection of northward migrating waders in the Sivash (Ukraine): the use of brine shrimp Artemia salina in a variably saline lagoon complex.

    NARCIS (Netherlands)

    Verkuil, Y.; Have, van der T.M.; Winden, van der J.; Chernichko, I.I.

    2003-01-01

    Wader species migrating through the Sivash (Ukraine) use hypersaline and brackish lagoons. We studied the use of the two habitat types, and focused on the profitability of Brine Shrimp Artemia salina, prey species in hypersaline lagoons for Dunlins Calidris alpina, Curlew Sandpipers Calidris ferrugi

  6. Habitat use and diet selection of northward migrating waders in the Sivash (Ukraine) : The use of Brine Shrimp Artemia salina in a variably saline lagoon complex

    NARCIS (Netherlands)

    Verkuil, Y; Van der Have, TM; Van der Winden, J; Chernichko, [No Value

    2003-01-01

    Wader species migrating through the Sivash (Ukraine) use hypersaline and brackish lagoons. We studied the use of the two habitat types, and focused on the profitability of Brine Shrimp Artemia salina, prey species in hypersaline lagoons for Dunlins Calidris alpina, Curlew Sandpipers Calidris ferrugi

  7. WILDLIFE HABITAT INVENTORY

    OpenAIRE

    GÜNDOĞDU, Ebubekir

    2009-01-01

    This study focused on what does habitat mean in wildlife, which factors it contains, how to make inventory for these factors and how to analyses habitat according to chosen species. In spite of habitat inventory has various meanings for varying areas and species by examining literature on this issue the most preferred habitat inventory standards are presented in this article. Keywords: Habitat, Inventory, Mapping

  8. The Habitat Connection.

    Science.gov (United States)

    Naturescope, 1987

    1987-01-01

    Consists of activities which address the causes of habitat destruction and the effects of habitat loss on animals and plants. Identifies habitat loss as the major reason for the endangerment and extinction of plant and animal species. (ML)

  9. Louisiana ESI: HABITATS (Habitat and Plant Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for coastal habitats in Louisiana. Vector polygons represent various habitats, including marsh types,...

  10. Two-dimensional physical habitat modeling of effects of habitat structures on urban stream restoration

    Directory of Open Access Journals (Sweden)

    Dongkyun IM

    2011-12-01

    Full Text Available River corridors, even if highly modified or degraded, still provide important habitats for numerous biological species, and carry high aesthetic and economic values. One of the keys to urban stream restoration is recovery and maintenance of ecological flows sufficient to sustain aquatic ecosystems. In this study, the Hongje Stream in the Seoul metropolitan area of Korea was selected for evaluating a physically-based habitat with and without habitat structures. The potential value of the aquatic habitat was evaluated by a weighted usable area (WUA using River2D, a two-dimensional hydraulic model. The habitat suitability for Zacco platypus in the Hongje Stream was simulated with and without habitat structures. The computed WUA values for the boulder, spur dike, and riffle increased by about 2%, 7%, and 131%, respectively, after their construction. Also, the three habitat structures, especially the riffle, can contribute to increasing hydraulic heterogeneity and enhancing habitat diversity.

  11. Habitat Selection by African Buffalo (Syncerus caffer) in Response to Landscape-Level Fluctuations in Water Availability on Two Temporal Scales

    OpenAIRE

    Emily Bennitt; Mpaphi Casper Bonyongo; Stephen Harris

    2014-01-01

    Seasonal fluctuations in water availability cause predictable changes in the profitability of habitats in tropical ecosystems, and animals evolve adaptive behavioural and spatial responses to these fluctuations. However, stochastic changes in the distribution and abundance of surface water between years can alter resource availability at a landscape scale, causing shifts in animal behaviour. In the Okavango Delta, Botswana, a flood-pulsed ecosystem, the volume of water entering the system dou...

  12. EcologicHabitat_WLH

    Data.gov (United States)

    Vermont Center for Geographic Information — The Wildlife Linkage Habitat Analysis uses landscape scale data to identify or predict the location of potentially significant wildlife linkage habitats (WLH)...

  13. Assessment of water chemistry, habitat, and benthic macroinvertebrates at selected stream-quality monitoring sites in Chester County, Pennsylvania, 1998-2000

    Science.gov (United States)

    Reif, Andrew G.

    2004-01-01

    Biological, chemical, and habitat data have been collected from a network of sites in Chester County, Pa., from 1970 to 2003 to assess stream quality. Forty sites in 6 major stream basins were sampled between 1998 and 2000. Biological data were used to determine levels of impairment in the benthic-macroinvertebrate community in Chester County streams and relate the impairment, in conjunction with chemical and habitat data, to overall stream quality. Biological data consisted of benthic-macroinvertebrate samples that were collected annually in the fall. Water-chemistry samples were collected and instream habitat was assessed in support of the biological sampling. Most sites in the network were designated as nonimpacted or slightly impacted by human activities or extreme climatic conditions on the basis of biological-metric analysis of benthic-macroinvertebrate data. Impacted sites were affected by factors, such as nutrient enrichment, erosion and sedimentation, point discharges, and droughts and floods. Streams in the Schuylkill River, Delaware River, and East Branch Brandywine Creek Basins in Chester County generally had low nutrient concentrations, except in areas affected by wastewater- treatment discharges, and stream habitat that was affected by erosion. Streams in the West Branch Brandywine, Christina, Big Elk, and Octoraro Creek Basins in Chester County generally had elevated nutrient concentrations and streambottom habitat that was affected by sediment deposition. Macroinvertebrate communities identified in samples from French Creek, Pigeon Creek (Schuylkill River Basin), and East Branch Brandywine Creek at Glenmoore consistently indicate good stream conditions and were the best conditions measured in the network. Macroinvertebrate communities identified in samples from Trout Creek (site 61), West Branch Red Clay Creek (site 55) (Christina River Basin), and Valley Creek near Atglen (site 34) (Octoraro Creek Basin) indicated fair to poor stream conditions and

  14. Characteristics of dominant fish assemblages in kelp bed habitat of Gouqi Island and distribution diversity in coastal area%枸杞岛海藻场优势种鱼类群体特征及其在不同生境中的差异

    Institute of Scientific and Technical Information of China (English)

    章守宇; 王蕾; 汪振华; 王凯; 林军

    2011-01-01

    In order to find out the characteristics and distribution of dominant fish assemblages in kelp beds of Gouqi Island, we sampled the fish assemblages in kelp beds and sandy beach every month from February 2009 to January 2010. The composition, biological characteristics and prey habits of dominant species were compared, separately. The results showed that the dominant fishes in kelp beds dominated by larger macroalgae Sargassum horueri or smaller algae, as Ulva pertusa were the same, I. E. Sebastiscus marmoratus, Agrammus agrammus and Nibea albiflora. The assemblages of 5. Marmoratus, with younger age and smaller size,have frequent prey activity along the coast and large variety in abundance. The strong recruitment of stock comes from the high reproduction of female, which were early sexual maturation and more than male in abundance. Prey variety of objects survived from the overfishing. The assemblages of both A. Agrammus and N. Albiflora were younger age and affected by the migration assemblages from open sea. The growth of above three species was different owing to the different feeding habits and prey objects. Meanwhile, due to the food conversion at the different stages of development, body variety and predation pressure from the top predator,S. Marmoratus and N. Albiflora will alter their choice in habitats for different utilization. A. Agrammus doesn' t change into prey objects in its life, so the main activity habitats are affected by Caprellidea, the major feeding target.%为了解枸杞岛岩礁不同底栖海藻分布的海藻场区域鱼类优势群体组成和分布特征,于2009年2月-2010年2月对枸杞岛海藻场和沙地生境的鱼类进行了逐月采样,对其中的鱼类优势种群组成、生物学特征和摄食规律作了比较.结果表明,以大型底栖海藻铜藻为优势种和以孔石莼等小型底栖海藻为优势种的海藻场鱼类全年优势种皆为褐菖鲉、斑头鱼和黄姑鱼.褐菖鲉群体具

  15. 3-D capacitance density imaging of fluidized bed

    Science.gov (United States)

    Fasching, George E.

    1990-01-01

    A three-dimensional capacitance density imaging of a gasified bed or the like in a containment vessel is achieved using a plurality of electrodes provided circumferentially about the bed in levels and along the bed in channels. The electrodes are individually and selectively excited electrically at each level to produce a plurality of current flux field patterns generated in the bed at each level. The current flux field patterns are suitably sensed and a density pattern of the bed at each level determined. By combining the determined density patterns at each level, a three-dimensional density image of the bed is achieved.

  16. Removal of selected pharmaceuticals from domestic wastewater in an activated sludge system followed by a horizontal subsurface flow bed - analysis of their respective contributions.

    Science.gov (United States)

    Verlicchi, P; Galletti, A; Petrovic, M; Barceló, D; Al Aukidy, M; Zambello, E

    2013-06-01

    Seventy-three commonly administered pharmaceuticals from twelve different therapeutic classes were investigated at a municipal wastewater treatment plant in northern Italy featuring a conventional activated sludge system (full-scale) and a polishing horizontal subsurface flow bed (pilot plant). Removal of these micro-pollutants by the two systems was assessed in order to evaluate their respective contributions. Mean concentrations and standard deviations were calculated and found to differ for the compounds detected, ranging from few ng/L to over 1,165 ng/L in the secondary effluent and from 11 to 533 in the polished effluent. Eighteen compounds were consistently below the detection limit and the remaining 55 compounds were found at a minimum of one sampling point. Average removal efficiencies of both treatment steps and in treatment train as a whole are evaluated and discussed, highlighting the difficulties in predicting the fate of pharmaceuticals in both an activated sludge system and a horizontal subsurface flow bed. Comparison between the observed average removal efficiencies and those reported in the literature was also carried out for the pharmaceuticals of interest, and the discrepancies that emerged are discussed. The investigated constructed wetland did show efficacy in removing some of these compounds, and it contributed to the overall removal efficiency of each therapeutic class. Indeed, evaluation of the specific mass loadings of each class of PhC detected in the raw wastewaters, secondary and polished effluent evidences that the investigated constructed wetland is able to further reduce the load of micropollutants, which could become a necessity, especially where the receiving water body is an effluent-dominant river and mitigation measures of the discharge impact are required to protect and safeguard the aquatic environment. PMID:23563255

  17. Migratory flows and foraging habitat selection by shorebirds along the northeastern coast of Brazil: The case of Baía de Todos os Santos

    Science.gov (United States)

    Lunardi, Vitor O.; Macedo, Regina H.; Granadeiro, José P.; Palmeirim, Jorge M.

    2012-01-01

    Large numbers of Nearctic shorebirds migrate and winter along the coast of northeastern Brazil, but there is little information on their migratory flows, foraging ecology, and on the structure of the species assemblages that they form with resident shorebirds. We studied these issues on intertidal flats of Baía de Todos os Santos (Bahia), the second largest bay in Brazil. During a full year cycle we carried out weekly bird counts in an intertidal area of 280 ha divided in sectors, where we also measured environmental parameters. The analyses of weekly counts resulted in a detailed phenology of use of the area by shorebirds. Five species were resident and ten were Nearctic migrants. Several of the latter had clear peaks in numbers in March and October, revealing the use of the bay as a stopover during both the north-bound and south-bound migration flows. A canonical correspondence analysis of the relationship between environmental parameters and bird numbers indicated that the foraging bird assemblage could be divided into five main groups, occupying distinct ecological gradients in the study area. The most important factors driving this structure were invertebrate prey abundance, percentage of fine sediments, area of mangrove cover and distance to channels. Our findings imply that maintenance of the diversity of intertidal habitats in this bay is crucial to satisfy the particular habitat requirements of resident and migrant shorebirds using the northeastern coastal regions of Brazil.

  18. Habitat classification modeling with incomplete data: pushing the habitat envelope.

    Science.gov (United States)

    Zarnetske, Phoebe L; Edwards, Thomas C; Moisen, Gretchen G

    2007-09-01

    Habitat classification models (HCMs) are invaluable tools for species conservation, land-use planning, reserve design, and metapopulation assessments, particularly at broad spatial scales. However, species occurrence data are often lacking and typically limited to presence points at broad scales. This lack of absence data precludes the use of many statistical techniques for HCMs. One option is to generate pseudo-absence points so that the many available statistical modeling tools can bb used. Traditional techniques generate pseudo-absence points at random across broadly defined species ranges, often failing to include biological knowledge concerning the species-habitat relationship. We incorporated biological knowledge of the species-habitat relationship into pseudo-absence points by creating habitat envelopes that constrain the region from which points were randomly selected. We define a habitat envelope as an ecological representation of a species, or species feature's (e.g., nest) observed distribution (i.e., realized niche) based on a single attribute, or the spatial intersection of multiple attributes. We created HCMs for Northern Goshawk (Accipiter gentilis atricapillus) nest habitat during the breeding season across Utah forests with extant nest presence points and ecologically based pseudo-absence points using logistic regression. Predictor variables were derived from 30-m USDA Landfire and 250-m Forest Inventory and Analysis (FIA) map products. These habitat-envelope-based models were then compared to null envelope models which use traditional practices for generating pseudo-absences. Models were assessed for fit and predictive capability using metrics such as kappa, threshold-independent receiver operating characteristic (ROC) plots, adjusted deviance (D(adj)2), and cross-validation, and were also assessed for ecological relevance. For all cases, habitat envelope-based models outperformed null envelope models and were more ecologically relevant

  19. Riparian Habitats - Sierra Nevada Foothill [ds304

    Data.gov (United States)

    California Department of Resources — These data are habitat polygons within a 200-m radius around point locations where wildlife surveys were conducted along 19 randomly selected watercourses in the...

  20. Effects of Surface-Water Diversions on Habitat Availability for Native Macrofauna, Northeast Maui, Hawaii

    Science.gov (United States)

    Gingerich, Stephen B.; Wolff, Reuben H.

    2005-01-01

    Effects of surface-water diversions on habitat availability for native stream fauna (fish, shrimp, and snails) are described for 21 streams in northeast Maui, Hawaii. Five streams (Waikamoi, Honomanu, Wailuanui, Kopiliula, and Hanawi Streams) were chosen as representative streams for intensive study. On each of the five streams, three representative reaches were selected: (1) immediately upstream of major surface-water diversions, (2) midway to the coast, and (3) near the coast. This study focused on five amphidromous native aquatic species (alamoo, nopili, nakea, opae, and hihiwai) that are abundant in the study area. The Physical Habitat Simulation (PHABSIM) System, which incorporates hydrology, stream morphology and microhabitat preferences to explore relations between streamflow and habitat availability, was used to simulate habitat/discharge relations for various species and life stages, and to provide quantitative habitat comparisons at different streamflows of interest. Hydrologic data, collected over a range of low-flow discharges, were used to calibrate hydraulic models of selected transects across the streams. The models were then used to predict water depth and velocity (expressed as a Froude number) over a range of discharges up to estimates of natural median streamflow. The biological importance of the stream hydraulic attributes was then assessed with the statistically derived suitability criteria for each native species and life stage that were developed as part of this study to produce a relation between discharge and habitat availability. The final output was expressed as a weighted habitat area of streambed for a representative stream reach. PHABSIM model results are presented to show the area of estimated usable bed habitat over a range of streamflows relative to natural conditions. In general, the models show a continuous decrease in habitat for all modeled species as streamflow is decreased from natural conditions. The PHABSIM modeling results

  1. Top Ten Bed Bug Tips

    Science.gov (United States)

    ... have bed bugs, not fleas, ticks or other insects. You can compare your insect to the pictures on our Identifying bed bugs ... bedbugs Bed Bugs Home Learn about Bed Bugs — Characteristics of Bed Bugs — Finding Bed Bugs Protecting Your ...

  2. Endocrine active chemicals, pharmaceuticals, and other chemicals of concern in surface water, wastewater-treatment plant effluent, and bed sediment, and biological characteristics in selected streams, Minnesota-design, methods, and data, 2009

    Science.gov (United States)

    Lee, Kathy E.; Langer, Susan K.; Barber, Larry B.; Writer, Jeff H.; Ferrey, Mark L.; Schoenfuss, Heiko L.; Furlong, Edward T.; Foreman, William T.; Gray, James L.; ReVello, Rhiannon C.; Martinovic, Dalma; Woodruff, Olivia R.; Keefe, Steffanie H.; Brown, Greg K.; Taylor, Howard E.; Ferrer, Imma; Thurman, E. Michael

    2011-01-01

    This report presents the study design, environmental data, and quality-assurance data for an integrated chemical and biological study of selected streams or lakes that receive wastewater-treatment plant effluent in Minnesota. This study was a cooperative effort of the U.S. Geological Survey, the Minnesota Pollution Control Agency, St. Cloud State University, the University of St. Thomas, and the University of Colorado. The objective of the study was to identify distribution patterns of endocrine active chemicals, pharmaceuticals, and other organic and inorganic chemicals of concern indicative of wastewater effluent, and to identify biological characteristics of estrogenicity and fish responses in the same streams. The U.S. Geological Survey collected and analyzed water, bed-sediment, and quality-assurance samples, and measured or recorded streamflow once at each sampling location from September through November 2009. Sampling locations included surface water and wastewater-treatment plant effluent. Twenty-five wastewater-treatment plants were selected to include continuous flow and periodic release facilities with differing processing steps (activated sludge or trickling filters) and plant design flows ranging from 0.002 to 10.9 cubic meters per second (0.04 to 251 million gallons per day) throughout Minnesota in varying land-use settings. Water samples were collected from the treated effluent of the 25 wastewater-treatment plants and at one point upstream from and one point downstream from wastewater-treatment plant effluent discharges. Bed-sediment samples also were collected at each of the stream or lake locations. Water samples were analyzed for major ions, nutrients, trace elements, pharmaceuticals, phytoestrogens and pharmaceuticals, alkylphenols and other neutral organic chemicals, carboxylic acids, and steroidal hormones. A subset (25 samples) of the bed-sediment samples were analyzed for carbon, wastewater-indicator chemicals, and steroidal hormones; the

  3. Comparation of logistic regression methods and discrete choice model in the selection of habitats Comparação dos métodos regressão logística e modelo de escolha discreta na seleção de habitats

    Directory of Open Access Journals (Sweden)

    Sandra Vergara Cardozo

    2010-01-01

    Full Text Available Based on a review of most recent data analyses on resource selection by animals as well as on recent suggestions that indicate the lack of an unified statistical theory that shows how resource selection can be detected and measured, the authors suggest that the concept of resource selection function (RSF can be the base for the development of a theory. The revision of discrete choice models (DCM is suggested as an approximation to estimate the RSF when the choice of animal or groups of animals involves different sets of available resource units. The definition of RSF requires that the resource which is being studied consists of discrete units. The statistical method often used to estimate the RSF is the logistic regression but DCM can also be used. The theory of DCM has been well developed for the analysis of data sets involving choices of products by humans, but it can also be applicable to the choice of habitat by animals, with some modifications. The comparison of the logistic regression with the DCM for one choice is made because the coefficient estimates of the logistic regression model include an intercept, which are not presented by the DCM. The objective of this work was to compare the estimates of the RSF obtained by applying the logistic regression and the DCM to the data set on habitat selection of the spotted owl (Strix occidentalis in the north west of the United States.Baseado em revisão mais recente de análises de dados em seleção de recurso pelos animais e com as mais recentes sugestões, que indicam a falta de uma teoria estatística unificada que mostre como a seleção do recurso pode ser detectada e medida, os autores sugerem que o conceito da função da seleção do recurso (RSF pode ser a base do desenvolvimento da teoria. A revisão de modelos de escolha discreta (DCM é sugerida como uma aproximação para estimar a RSF quando a escolha do animal os grupos de animais envolvem diferentes conjuntos de unidades de

  4. River habitats for salmonids on the River Lune catchment

    OpenAIRE

    2000-01-01

    An extensive survey of the River Lune using River Habitat Survey (RHS) was commissioned to assess the habitat quality of the Lune for salmonid fish. The main river on the Lune and tributaries were divided into 500m sections. A sample of 103 sections (25% of the total classified length) was randomly selected and surveyed in February/March 99. A Habitat Modification Score (HMS) describing the level of habitat modification was derived for each site and compared to the whole reference net...

  5. Predictive Seagrass Habitat Model

    Science.gov (United States)

    Restoration of ecosystem services provided by seagrass habitats in estuaries requires a firm understanding of the modes of action of multiple interacting stressors including nutrients, climate change, coastal land-use change, and habitat modification. We explored the application...

  6. EcologicHabitat_WCV

    Data.gov (United States)

    Vermont Center for Geographic Information — WCV describes the value of the Wildlife Habitat Suitability as it approaches the state highway system. This analysis was designed to use the Wildlife Habitat...

  7. Habitat monitoring plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Management of habitat is required in order to achieve the refuge purpose and wildlife objectives. The Upland Habitat Management Plan (1993, Interim Plan) and the...

  8. California Condor Critical Habitat

    Data.gov (United States)

    California Department of Resources — These Data identify (in general) the areas where critical habitat for the California Condor occur. Critical habitat for the species consists of the following 10...

  9. Cross Shelf Patterns in Habitat Selectivity of Hawkfish (Family: Cirrhitidae) in the Red Sea; with a Special Case of Varying Color Morphs in Paracirrhites forsteri.

    KAUST Repository

    Chaidez, Veronica

    2015-01-01

    Not much is known about hawkfish worldwide including those that occur in the understudied Red Sea reef system. Hawkfishes are small reef predators that perch in ambush-ready positions and shelter within or on various substrates including live and dead coral. The aim of this study was to look at the distribution and abundance patterns of Red Sea hawkfishes across an inshore and offshore gradient and to investigate the use of benthic habitats. This study was conducted on three inshore, four midshore, and two offshore reefs with surveys at 8 meters and along the reef crest. In total, three species were documented: Paracirrhites forsteri, Cirrhitichthys oxycephalus, and Cirrhitus spilotoceps. We found clear distinctions between depth zones and between continental shelf positions. Cirrhitichthys oxycephalus only occurs at the reef slope and Cirrhitus spilotoceps is only found on reef crests. Paracirrhites forsteri was the most abundant species across all reefs and was found in four varying color morphs. Morph 1 showed the most evidence of being a generalist as it utilized the greatest number of substrates. All three species were more abundant on midshore and offshore reefs which have healthier, intact coral communities. Coral cover is a good indicator of hawkfish abundance even when the species in question does not utilize live coral directly.

  10. The Influence of Salmonid Spawning on Grain Architecture, Critical Bed Shear Stress, and Bed Load Transport in Streams

    Science.gov (United States)

    Buxton, T.; Buffington, J. M.; Yager, E. M.; Fremier, A. K.; Hassan, M. A.

    2012-12-01

    Salmonid spawning occurs in many high to mid-order streams in North America and Europe, but the detailed mechanics of this disturbance on stream bed mobility is not well studied. We calculated and measured spawning effects on incipient bed mobility and sediment transport in a laboratory flume and found that the tailspill portion of simulated spawning nests ("redds") are less stable than unspawned beds. This result agrees with field research by others, but counters prior calculations of tailspill stability that used grain architecture relationships derived from unspawned beds. Redds have coarser and better sorted surfaces, which reduce grain exposure and protrusion compared to unspawned beds, but load cell measurements of the total resistance to movement of grains on redds were lower despite deeper grain pockets and larger pivot angles. This is because the redd-building process flushed fine sediment that had previously cemented bed material, resulting in a looser bed structure and more mobile grains. These observations are supported by force balance calculations of critical shear stress on redds being lower on average than on unspawned beds. Computational results are supported by visual observations and measurements of bed load transport from redds and unspawned beds in the flume, where redds mobilized sooner and exhibited a higher sediment transport rate than unspawned beds. Redds were observed to erode by translating, then dispersing and evacuating downstream, before grains on the unspawned bed mobilized. Further increase in discharge mobilized greater proportions of the unspawned bed but did not scour the deeper portion of redds where spawners deposit their eggs. Our results suggest both an evolutionary trade-off and advantage to large spawning populations. Namely, the structurally loose tailspill likely increases intragravel flow to eggs at the expense of tailspill instability, which may sufficiently elevate sediment yields in streams with high spawner densities

  11. Lugworm ( Abarenicola affinis) in seagrass and unvegetated habitats

    Science.gov (United States)

    Goerlitz, Stefan; Berkenbusch, Katrin; Probert, P. Keith

    2015-06-01

    In Otago, southern New Zealand, the lugworm Abarenicola affinis resides in neighbouring tidal inlets with and without seagrass ( Zostera muelleri). A comparison of abundance, body size and biomass of A. affinis between seagrass habitat (Papanui Inlet) and unvegetated habitat (Hoopers Inlet) showed little seasonal variation of these parameters in each habitat and relatively similar abundances between both habitats. In contrast, lugworm biomass was considerably lower in the seagrass habitat due to the lack of large individuals compared with unvegetated habitat. In the seagrass habitat, there was a significant negative influence of Z. muelleri below-ground biomass on abundance and biomass of A. affinis, indicating that seagrass affected lugworm burrowing and/or feeding processes. In contrast to the unvegetated habitat, where lugworms spread relatively evenly across the intertidal area, lugworms were mostly restricted to the upper intertidal zone in the seagrass habitat. The findings suggest that the extensive seagrass bed in the mid and low intertidal zones of Papanui Inlet limited lugworm distribution in an otherwise suitable habitat. Whereas small lugworms colonised seagrass areas, the largest individuals occurred only in unvegetated sediment and seemed to be more hampered by the presence of seagrass than smaller individuals. The findings highlight negative feedback between antagonistic ecosystem engineers, with the potential of seagrass physical structures (autogenic engineering) to impact negatively on lugworm activity (allogenic engineering).

  12. River Bed Sediment Classification Using Acoustic Doppler Profiler

    Science.gov (United States)

    Shields, F. D.

    2008-12-01

    Restoration or rehabilitation of degraded stream and river habitats requires definition of a target condition and preferably post-implementation monitoring to gage progress toward the target. Stream habitat has been characterized by computing statistics based on measurements of water depth and velocity at each point of a horizontal grid. In many cases stream bed type and cover, both qualitatively assessed, were included as additional grid variables. Resultant statistics describing the central tendency, variability and spatial distribution of these three or four variables and their combinations have been used to explain key differences between more- and less-degraded streams and to infer biotic responses. Usually the required data are collected by wading observers, but application to larger rivers is problematic. Collection of water depth and velocity information may be automated across a wide range of stream sizes using an acoustic Doppler profiler (aDp). Herein we suggest that aDp data may also be used to infer bed hardness and thus type by extracting the return signal strength from the bottom track signal and using this information to compute the echo intensity at the bed. A method for computing echo intensity, along with key assumptions is presented. Echo intensity is computed for a range of river environments and related to the size and related characteristics of bed material. Habitat maps for river reaches depicting water depth, velocity and bed type developed from aDp data sets are presented.

  13. Population genetic structure of the freshwater snail, Bulinus globosus, (Gastropoda: Planorbidae) from selected habitats of KwaZulu-Natal, South Africa.

    Science.gov (United States)

    Mkize, Lwamkelekile Sitshilelo; Mukaratirwa, Samson; Zishiri, Oliver Tendayi

    2016-09-01

    The freshwater snail Bulinus globosus is an important intermediate host of Schistosoma haematobium, the causative agent of urinary schistosomiasis. This disease is of major health concern, especially in Africa where the majority of cases have been reported. In this study the inter- and intra-genetic diversity and population genetic structure of B. globosus from nine locations in the KwaZulu-Natal province of South Africa was studied using four polymorphic microsatellite loci (BgZ1-BgZ4). Moderate genetic diversity was detected within populations with a mean diversity (HE) of 0.49±0.09. The majority of populations significantly deviated from Hardy-Weinberg equilibrium (p<0.05), due to a deficit of heterozygotes. Such deviations may be due to founder events that were caused by bottlenecks that occurred as a result of frequent droughts and flooding that these snails' habitats are exposed to. Overall, the populations studied seem to be partially inbreeders/selfers with mean estimates of 0.24/0.38. A discernable genetic structure was elucidated among populations as evident by the mean pairwise FST of 0.58±0.13. There was no significant association between genetic and geographical distance among populations, an indication of limited gene flow. This increases the chances of populations losing alleles due to genetic drift. Populations in close proximity demonstrated high genetic differentiation (58.77% total variation) due to allelic differences between them. The sample populations fell into 12 clusters, however, the populations from uMkhanyakude and uThungulu exhibited no discernable genetic structure. Genetically, the Bhobhoyi site found within the uGu district was equidistant to the two main sampling regions. PMID:27267152

  14. Bed In Summer

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    In winter I get up at night And dress by yellow candle-light. In summer, quite the other way, I have to go to bed by day. I have to go to bed and see The birds still hopping on the tree, Or hear the grown-up people' s feet Still going past me in the stree

  15. Fluidized bed incinerator development

    International Nuclear Information System (INIS)

    A fluidized bed incinerator is being developed for burning rad contaminated solid and liquid waste materials. In situ neutralization of acid gases by the bed material, catalytic afterburning, and gas filtration are used to produce a clean flue gas without the use of aqueous scrubbing

  16. Fluidized bed calciner apparatus

    Science.gov (United States)

    Owen, Thomas J.; Klem, Jr., Michael J.; Cash, Robert J.

    1988-01-01

    An apparatus for remotely calcining a slurry or solution feed stream of toxic or hazardous material, such as ammonium diurante slurry or uranyl nitrate solution, is disclosed. The calcining apparatus includes a vertical substantially cylindrical inner shell disposed in a vertical substantially cylindrical outer shell, in which inner shell is disposed a fluidized bed comprising the feed stream material to be calcined and spherical beads to aid in heat transfer. Extending through the outer and inner shells is a feed nozzle for delivering feed material or a cleaning chemical to the beads. Disposed in and extending across the lower portion of the inner shell and upstream of the fluidized bed is a support member for supporting the fluidized bed, the support member having uniform slots for directing uniform gas flow to the fluidized bed from a fluidizing gas orifice disposed upstream of the support member. Disposed in the lower portion of the inner shell are a plurality of internal electric resistance heaters for heating the fluidized bed. Disposed circumferentially about the outside length of the inner shell are a plurality of external heaters for heating the inner shell thereby heating the fluidized bed. Further, connected to the internal and external heaters is a means for maintaining the fluidized bed temperature to within plus or minus approximately 25.degree. C. of a predetermined bed temperature. Disposed about the external heaters is the outer shell for providing radiative heat reflection back to the inner shell.

  17. North Slope, Alaska ESI: HABITATS (Habitat Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for benthic marine habitats for the North Slope of Alaska. Vector polygons in this data set represent...

  18. Bathing a patient in bed

    Science.gov (United States)

    Bed bath; Sponge bath ... Some patients cannot safely leave their beds to bathe. For these people, daily bed baths can help keep their skin healthy, control odor, and increase comfort. If moving the ...

  19. A review on packed bed solar energy storage systems

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Harmeet; Saini, R.P. [Alternate Hydro Energy Centre, Indian Institute of Technology Roorkee, Roorkee 247667 (India); Saini, J.S. [Mechanical and Industrial Engineering Department, Indian Institute of Technology Roorkee, Roorkee 247667 (India)

    2010-04-15

    Because of intermittent nature of solar energy, storage is required for uninterrupted supply in order to match the needs. Packed beds are generally used for storage of thermal energy from solar air heaters. A packed bed is a volume of porus media obtained by packing particles of selected material into a container. A number of studies carried out on packed beds for their performance analysis were reported in the literature. These studies included the design of packed beds, materials used for storage, heat transfer enhancement, flow phenomenon and pressure drop through packed beds. This paper presents an extensive review on the research carried out on packed beds. Based on the literature review, it is concluded that most of the studies carried out are on rocks and pebbles as packing material. A very few studies were conducted on large sized packing materials. Further no study has been reported so far on medium sized storage elements in packed beds. (author)

  20. Wind power project. Investigation of the habitat use of selected native small game species in the vicinity of wind power systems. Final report; Projekt Windkraftanlagen. Untersuchungen zur Raumnutzung ausgewaehlter heimischer Niederwildarten im Bereich von Windkraftanlagen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Pohlmeyer, K.; Menzel, C.

    2001-04-01

    Acting on behalf of the State Hunting Association of Lower Saxony the Game Research Institute (IWFo) of Hannover Veterinary University carried out a three-year study from April 1998 through March 2001 on the habitat use of selected native small game species in the vicinity of aerogenerators. This final report depicts the animals' preferred places, use of agricultural land, avoidance radius, if any, their activities and exposure to predator pressure. The target species were roe deer, hare, red fox, partridge and carrion crow. The study was carried out in Lower Saxony and Bremen on a total study area of 22.3 km{sup 2}, comprising four areas with running aerogenerators and five control areas without an aerogenerator. All parameters were studied in terms of a comparison between aerogenerator and control areas. The objective was to identify differences in population, use of space and habitat and in behaviour. [German] Am Institut fuer Wildtierforschung an der Tieraerztlichen Hochschule Hannover (IWFo) wurde im Auftrag der Landesjaegerschaft Niedersachsen (LJN) in einer dreijaehrigen Studie von April 1998 bis Maerz 2001 die Raumnutzung ausgewaehlter heimischer Niederwildarten im Bereich von Windkraftanlagen (WKA) untersucht. Im Weiteren wurden Aufenthaltspraeferenzen, Nutzung der landwirtschaftlichen Flaechen, moegliche Naeherungslimits und Aktivitaeten der Wildarten sowie der Beutegreiferdruck dargestellt. Zielarten der Studie waren Rehwild, Feldhase, Rotfuchs, Rebhuhn und Rabenkraehen. Die Untersuchungen wurden in vier Gebieten mit in Betrieb befindlichen WKA sowie in fuenf Referenzgebieten ohne WKA in Niedersachsen und Bremen auf einer Flaeche von insgesamt 22,3 km{sup 2} durchgefuehrt. Alle Parameter wurden vergleichend fuer die WKA- und Referenzgebiete betrachtet. Moegliche Unterschiede im Besatz bzw. Bestand, in Raum- und Habitatnutzung sowie im Verhalten wurden herausgearbeitet. (orig.)

  1. Shorebird Habitat Suitability Indicies

    Data.gov (United States)

    Arctic Landscape Conservation Cooperative — This dataset consists of predicted habitat suitability indices and species richness for eight shorebird species (Black-bellied Plover [Pluvialis squatarola],...

  2. Feeding habitat selection by Mongolia gazelle (Procapra gutturosa) in Dalai Lake area of Inner Mongolia in winter%内蒙古达赉湖地区蒙原羚冬季采食生境选择

    Institute of Scientific and Technical Information of China (English)

    童杰; 刘丙万; 刘松涛; 包黎明

    2012-01-01

    Mongolian gazelle ( procapra gutturosa) is the most abundant and endemic ungulate species in Asia-European temperate steppe ecosystems. In this study, an investigation was conducted from November 2010 to January 2011 to understand the feeding habitat selection by Mongolian gazelle in the Dalai Lake area of Inner Mongolia in winter. The Mongolian gazelle preferred to select the habitats with 50 g ? rrT2 aboveground biomass, 1000-2000 m fence distance, >20 cm plant height, >40% vegetation cover, 3000-4000 m visible range shelter, >2000 m settlement distance, >2000 m livestock distance, <20° slope, middle and upper slope position, and Stipa spp. And Aneurolepidium chinese vegetation types. Stepwise discriminate analysis showed that the four most important ecological factors affecting the feeding habitat selection in winter were fence distance, snow depth, aboveground biomass, and shelter in turn, based on their contribution values. The accuracy of the discrimination was 82. 1% . To establish a reasonable fence management system and to increase the abundance of available food would be the key issues for the protection of Mongolian gazelle.%蒙原羚是欧亚大陆温带草原生态系统中的特有物种和数量最多的有蹄类动物.2010年11月-2011年1月,在内蒙古达赉湖地区开展了蒙原羚冬季采食生境选择研究.结果表明:蒙原羚冬季选择利用雪深<6 cm,地上生物量>50 g·m-2,距围栏1000 ~2000 m,植被高度>20 cm,植被盖度>40%,隐蔽条件(可视距离)3000~4000 m,到居民点距离>2000 m,距家畜>2000 m,坡度<20°,中上坡位,针茅(Stipa spp.)和羊草(Aneurolepidium chinnenses)等植被类型的生境采食;生境因子综合影响蒙原羚的冬季采食生境选择,依照贡献值的大小依次为到围栏距离、地上生物量、雪深和隐蔽条件.逐步判别分析表明,由这4个变量构成的判别方程在对蒙原羚采食样方进行区分时,正确判别率为82.1%.因此,建

  3. Tapered bed bioreactor

    Science.gov (United States)

    Scott, Charles D.; Hancher, Charles W.

    1977-01-01

    A vertically oriented conically shaped column is used as a fluidized bed bioreactor wherein biologically catalyzed reactions are conducted in a continuous manner. The column utilizes a packing material a support having attached thereto a biologically active catalytic material.

  4. Particle fuel bed tests

    International Nuclear Information System (INIS)

    Gas-cooled reactors, using packed beds of small diameter coated fuel particles have been proposed for compact, high-power systems. The particulate fuel used in the tests was 800 microns in diameter, consisting of a thoria kernel coated with 200 microns of pyrocarbon. Typically, the bed of fuel particles was contained in a ceramic cylinder with porous metallic frits at each end. A dc voltage was applied to the metallic frits and the resulting electric current heated the bed. Heat was removed by passing coolant (helium or hydrogen) through the bed. Candidate frit materials, rhenium, nickel, zirconium carbide, and zirconium oxide were unaffected, while tungsten and tungsten-rhenium lost weight and strength. Zirconium-carbide particles were tested at 2000 K in H2 for 12 hours with no visible reaction or weight loss

  5. Enuresis (Bed-Wetting)

    Science.gov (United States)

    ... get out of bed to go to the bathroom. When do most children achieve bladder control? Children ... ask questions about your child's daytime and nighttime bathroom habits. Then your doctor will do a physical ...

  6. Larkin Mill Dam bed sediment particle diameter from 2008-06-09 to 2016-03-30 (NCEI Accession 0152462)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — We are collecting stream channel geometry and bed sediment grain size distribution data at the Parker River to evaluate physical habitat changes associated with the...

  7. Sedgeunkedunk stream bed sediment particle diameter from 2007-08-15 to 2016-03-30 (NCEI Accession 0152487)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — We are collecting stream channel geometry and bed sediment grain size distribution data at Sedgeunkedunk stream to evaluate physical habitat changes associated with...

  8. Bed rest and immunity

    Science.gov (United States)

    Sonnenfeld, Gerald; Aviles, Hernan; Butel, Janet S.; Shearer, William T.; Niesel, David; Pandya, Utpal; Allen, Christopher; Ochs, Hans D.; Blancher, Antoine; Abbal, Michel

    2007-02-01

    Space flight has been shown to result in altered immune responses. The current study was designed to investigate this possibility by using the bed rest model of some space flight conditions. A large number of women are included as subjects in the study. The hypothesis being tested is: 60 days head-down tilt bed rest of humans will affect the immune system and resistance to infection. Blood, urine and saliva samples will be obtained from bed rest subjects prior to, at intervals during, and after completion of 60 days of head-down tilt bed rest. Leukocyte blastogenesis, cytokine production and virus reactivation will be assessed. The ability of the subjects to respond appropriately to immunization with the neoantigen bacteriophage φX-174 will also be determined. Bed rest is being carried out at MEDES, Toulouse France, and the University of Texas Medical Branch, Galveston, TX. The studies to be carried out in France will also allow assessment of the effects of muscle/bone exercise and nutritional countermeasures on the immune system in addition to the effects of bed rest.

  9. Modelling the Influence of Long-Term Hydraulic Conditions on Juvenile Salmon Habitats in AN Upland Scotish River

    Science.gov (United States)

    Fabris, L.; Malcolm, I.; Millidine, K. J.; Buddendorf, B.; Tetzlaff, D.; Soulsby, C.

    2015-12-01

    Wild Atlantic salmon populations in Scottish rivers constitute an important economic and recreational resource, as well as being a key component of biodiversity. Salmon have very specific habitat requirements at different life stages and their distribution is therefore strongly influenced by a complex suite of biological and physical controls. Previous research has shown that stream hydrodynamics and channel morphology have a strong influence on the distribution and density of juvenile salmon. Here, we utilise a unique 20 year data set of spatially distributed juvenile salmon densities derived from annual electro-fishing surveys in an upland Scottish river. We examine to what extent the spatial and temporal variability of in-stream hydraulics regulates the spatial and temporal variability in the performance and density of juvenile salmon. A 2-D hydraulic model (River2D) is used to simulate water velocity and water depth under different flow conditions for seven different electro-fishing sites. The selected sites represent different hydromorphological environments including plane-bed, step-pool and pool riffle reaches. The bathymetry of each site was characterised using a total station providing an accurate DTM of the bed, and hydraulic simulations were driven by 20 year stream flow records. Habitat suitability curves, based on direct observations during electro-fishing surveys, were produced for a range of hydraulic indices for juvenile salmon. The hydraulic simulations showed marked spatial differences in juvenile habitat quality both within and between reaches. They also showed marked differences both within and between years. This is most evident in extreme years with wet summers when salmon feeding opportunities may be constrained. Integration of hydraulic habitat models, with fish preference curves and the long term hydrological data allows us to assess whether long-term changes in hydroclimate may be affecting juvenile salmonid populations in the study stream

  10. Thermal modeling of microwave heated packed and fluidized bed catalytic reactors.

    Science.gov (United States)

    Thomas, J R; Faucher, F

    2000-01-01

    Thermal models of small-scale, microwave-heated, packed-bed and fluidized-bed catalytic chemical reactors were developed to investigate the possibility of selectively heating the catalyst sites or the catalyst pellets with microwaves. Results indicate catalyst sites may be selectively heated under special conditions in a packed or fluidized bed, and catalyst pellets may be heated above the temperature of the cooling(and reacting) gas under certain conditions in a fluidized bed. PMID:11098441

  11. Generalisation of physical habitat-discharge relationships

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available Physical habitat is increasingly used worldwide as a measure of river ecosystem health when assessing changes to river flows, such as those caused by abstraction. The major drawback with this approach is that defining precisely the relationships between physical habitat and flow for a given river reach requires considerable data collection and analysis. Consequently, widely used models such as the Physical Habitat Simulation (PHABSIM system are expensive to apply. There is, thus, a demand for rapid methods for defining habitat-discharge relationships from simple field measurements. This paper reports the analysis of data from 63 sites in the UK where PHABSIM has been applied. The results demonstrate that there are strong relationships between single measurements of channel form and river hydraulics and the habitat available for target species. The results can form the basis of a method to estimate sensitivity of physical habitat to flow change by visiting a site at only one flow. Furthermore, the uncertainty in estimates reduces as more information is collected. This allows the user to select the level of investment in data collection appropriate for the desired confidence in the estimates. The method is demonstrated using habitat indicators for different life stages of Atlantic salmon, brown trout, roach and dace.

  12. Advanced Plant Habitat (APH)

    Science.gov (United States)

    Richards, Stephanie E. (Compiler); Levine, Howard G.; Reed, David W.

    2016-01-01

    The Advanced Plant Habitat (APH) hardware will be a large growth volume plant habitat, capable of hosting multigenerational studies, in which environmental variables (e.g., temperature, relative humidity, carbon dioxide level light intensity and spectral quality) can be tracked and controlled in support of whole plant physiological testing and Bio-regenerative Life Support System investigations.

  13. 秦岭大熊猫栖息地选择与森林群落%Relationship between Habitat Selection of Giant Panda and Forest Community Characters in Qinling Mountains

    Institute of Scientific and Technical Information of China (English)

    孙飞翔; 党坤良; 陈俊娴

    2013-01-01

    This study was conducted at forest communities of giant panda habitats in Foping National Nature Reserve,Longcaoping Nature Reserve and Pingheliang Nature Reserve.The data of altitude,slope,aspect,canopy density,shrub coverage,bamboo density and bamboo biomass were collected to conduct cluster analysis and factor analysis.The results showed that the forest communities of the winter habitat of the giant panda were mainly constituted by Quercus aliena var.acuteserrata forests.The slopes were relatively plain with an average degree of 11.7°and the slope aspects were mainly Southeast; The canopy density,shrub coverage,bamboo density,bamboo biomass were 0.59,74%,92 800 plants,hm-2 and 15.78 t· hm-2,respectively.The forest communities of the summer habitat of the giant panda habitat were mainly constituted by Abiesfargesii forests.The slopes were relatively gentle with an average degree of 17.2°and the slope aspects were mainly Southeast and Northeast.The canopy density,shrub coverage,bamboo density,bamboo biomass were 0.6,71%,465 600 plants· hm-2and 8.76 t-hm-2,respectively.According to the results of factor analysis,the bamboo biomass and shrub coverage were the main factors regulating the habitat selection of giant pandas,which may be closely related to ample food resources for giant pandas in those habitats.%以海拔、坡度、坡向、郁闭度、灌木盖度、竹子密度以及竹子生物量等指标为自变量,对秦岭大熊猫冬季栖息地森林群落进行聚类分析和因子分析.结果表明:秦岭大熊猫冬季栖息地居地森林群落主要以锐齿栎林为主,地形较为平坦,平均坡度为11.7°,坡向以东南坡为主;乔木的郁闭度为0.59,其高度、胸径和年龄都最大而密度和多样性指数最低;灌木的盖度、高度都比较高而多样性指数比较低,分别为0.74,1.77 m,0.76;竹子的密度和生物量也都比较高,分别为9.28万株,hm-2,15.78 t·hm-2.夏季栖息地森林群落以巴山冷杉

  14. Seasonal meso- and microhabitat selection by the northern snakehead (Channa argus) in the Potomac river system

    Science.gov (United States)

    Lapointe, N.W.R.; Thorson, J.T.; Angermeier, P.L.

    2010-01-01

     The northern snakehead (Channa argus) is a large piscivorous fish that is invasive in eastern Europe and has recently been introduced in North America. We examined the seasonal habitat selection at meso- and microhabitat scales using radio-telemetry to increase understanding of the ecology of this species, which will help to inform management decisions. After the spawning season (postspawn season, September–November), northern snakeheads preferred offshore Eurasian water-milfoil (Myriophyllum spicatum) beds with shallow water (∼115 cm) and soft substrate. In the winter (November–April), these fish moved to deeper water (∼135 cm) with warmer temperatures, but habitat selection was weak at both scales. Northern snakeheads returned to shallower water (∼95 cm) in the prespawn season (April–June) and used milfoil and other cover. Habitat selection was the strongest at both meso- and microhabitat scales during the spawning season (June–September), when fish preferred macrophytes and cover in shallow water (∼88 cm). Our results help to identify habitats at the risk of invasion by northern snakeheads. We suggest that control efforts and future research focus on shallow waters, and take into consideration the seasonal habitat preferences.

  15. An artificial water body provides habitat for an endangered estuarine seahorse species

    Science.gov (United States)

    Claassens, Louw

    2016-10-01

    Anthropogenic development, especially the transformation of natural habitats to artificial, is a growing concern within estuaries and coastal areas worldwide. Thesen Islands marina, an artificial water body, added 25 ha of new estuarine habitat to the Knysna Estuary in South Africa, home to the Knysna seahorse. This study aimed to answer: (I) Can an artificial water body provide suitable habitat for an endangered seahorse species? And if so (II) what characteristics of this new habitat are important in terms of seahorse utilization? Four major habitat types were identified within the marina canals: (I) artificial reno mattress (wire baskets filled with rocks); (II) Codium tenue beds; (III) mixed vegetation on sediment; and (IV) barren canal floor. Seahorses were found throughout the marina system with significantly higher densities within the reno mattress habitat. The artificial water body, therefore, has provided suitable habitat for Hippocampus capensis, a noteworthy finding in the current environment of coastal development and the increasing shift from natural to artificial.

  16. Microevolutionary Effects of Habitat Fragmentation on Plant-Animal Interactions

    OpenAIRE

    Fontúrbel, Francisco E.; Maureen M. Murúa

    2014-01-01

    Plant-animal interactions are a key component for biodiversity maintenance, but they are currently threatened by human activities. Habitat fragmentation might alter ecological interactions due to demographic changes, spatial discontinuities, and edge effects. Also, there are less evident effects of habitat fragmentation that potentially alter selective forces and compromise the fitness of the interacting species. Changes in the mutualistic and antagonistic interactions in fragmented habitats ...

  17. Macrofaunal communities associated with chemosynthetic habitats from the U.S. Atlantic margin: A comparison among depth and habitat types

    Science.gov (United States)

    Bourque, Jill R.; Robertson, Craig M.; Brooke, Sandra; Demopoulos, Amanda

    2016-01-01

    Hydrocarbon seeps support distinct benthic communities capable of tolerating extreme environmental conditions and utilizing reduced chemical compounds for nutrition. In recent years, several locations of methane seepage have been mapped along the U.S. Atlantic continental slope. In 2012 and 2013, two newly discovered seeps were investigated in this region: a shallow site near Baltimore Canyon (BCS, 366–412 m) and a deep site near Norfolk Canyon (NCS, 1467–1602 m), with both sites containing extensive chemosynthetic mussel bed and microbial mat habitats. Sediment push cores, suction samples, and Ekman box cores were collected to quantify the abundance, diversity, and community structure of benthic macrofauna (>300 μm) in mussel beds, mats, and slope habitats at both sites. Community data from the deep site were also assessed in relation to the associated sediment environment (organic carbon and nitrogen, stable carbon and nitrogen isotopes, grain size, and depth). Infaunal assemblages and densities differed both between depths and among habitat types. Macrofaunal densities in microbial mats were four times greater than those present in mussel beds and slope sediments and were dominated by the annelid families Dorvilleidae, Capitellidae, and Tubificidae, while mussel habitats had higher proportions of crustaceans. Diversity was lower in BCS microbial mat habitats, but higher in mussel and slope sediments compared to NCS habitats. Multivariate statistical analysis revealed specific sediment properties as important for distinguishing the macrofaunal communities, including larger grain sizes present within NCS microbial mat habitats and depleted stable carbon isotopes (δ13C) in sediments present at mussel beds. These results suggest that habitat differences in the quality and source of organic matter are driving the observed patterns in the infaunal assemblages, including high β diversity and high variability in the macrofaunal community composition. This

  18. Invaded habitats. Chapter 4

    Directory of Open Access Journals (Sweden)

    Carlos Lopez-Vaamonde

    2010-07-01

    Full Text Available More than 65% (1040 species of arthropod species alien to Europe are associated with human-made habitats, especially parks and gardens, human settlements and agricultural lands, whereas woodlands are yet colonized by less than 20% of the alien fauna, which still has a negligible representation in the other natural and semi-natural habitats. Large differences in habitat affinity are observed between alien taxonomic groups. Phytophagous species are predominant among aliens, representing 47.2% of species alien to Europe.

  19. Bed bug deterrence

    Directory of Open Access Journals (Sweden)

    Haynes Kenneth F

    2010-09-01

    Full Text Available Abstract A recent study in BMC Biology has determined that the immature stage of the bed bug (the nymph signals its reproductive status to adult males using pheromones and thus avoids the trauma associated with copulation in this species. The success of this nymphal strategy of deterrence is instructive. Against the background of increasing problems with bed bugs, this research raises the question whether pheromones might be used to control them. See research article http://www.biomedcentral.com/1741-7007/8/121

  20. in Spouted Bed

    Directory of Open Access Journals (Sweden)

    Bronislaw Buczek

    2013-01-01

    Full Text Available Samples of active coke, fresh and spent after cleaning flue gases from communal waste incinerators, were investigated. The outer layers of both coke particles were separately removed by comminution in a spouted bed. The samples of both active cokes were analysed by means of densities, mercury porosimetry, and adsorption technique. Remaining cores were examined to determine the degree of consumption of coke by the sorption of hazardous emissions (SO2, HCl, and heavy metals through its bed. Differences in contamination levels within the porous structure of the particles were estimated. The study demonstrated the effectiveness of commercial active coke in the cleaning of flue gases.

  1. Trade-offs in Daphnia habitat selection

    NARCIS (Netherlands)

    Winder, M.; Spaak, P.; Mooij, W.M.

    2004-01-01

    Diel vertical migration (DVM) is a dynamic behavioral pattern found extensively in the world's oceans and lakes, yet the role of food and temperature distribution on DVM is still unclear. While DVM has been mostly studied in systems with surface food maxima, deep-water food maxima are quite common i

  2. Selecting habitat management strategies on refuges

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report is a joint effort of the Biological Resources Division, U.S. Geological Survey and the U.S. Fish and Wildlife Service (FWS) to provide National Wildlife...

  3. Smalltooth Sawfish Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for smalltooth sawfish (Pristis pectinatat) as designated by 74 FR 45353, September 2, 2009, Rules and Regulations.

  4. Johnsons Seagrass Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for Johnson's Seagrass as designated by Federal Register Vol. 65, No. 66, Wednesday, April 5, 2000, Rules and Regulations.

  5. Right Whale Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for Right Whale as designated by Federal Register Vol. 59, No. 28805, May 19, 1993, Rules and Regulations.

  6. Habitat Mapping Camera (HABCAM)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset entails imagery collected using the HabCam towed underwater vehicle and annotated data on objects or habitats in the images and notes on image...

  7. Critical Habitat Designations

    Data.gov (United States)

    Department of Homeland Security — The Endangered Species Act (ESA) requires the Federal government to designate 'critical habitat' for any species it lists under the ESA. This dataset combines both...

  8. Designated Critical Habitat

    Data.gov (United States)

    Kansas Data Access and Support Center — Critical habitats include those areas documented as currently supporting self-sustaining populations of any threatened or endangered species of wildlife as well as...

  9. Green Turtle Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for green turtle as designated by Federal Register Vol. 63, No. 46701, September 2, 1998, Rules and Regulations.

  10. Green Turtle Critical Habitat

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data represent the critical habitat for green turtle as designated by Federal Register Vol. 63, No. 46701, September 2, 1998, Rules and Regulations.

  11. Habitats, activities, and signs

    DEFF Research Database (Denmark)

    Andersen, Peter Bøgh; Brynskov, Martin

    2004-01-01

    Digital habitats is a framework for designing and modeling environments for activities that involve mobile and embedded computing systems. This paper 1) introduces the basic concepts of the framework, i.e. activity, thematic role, and the three ‘dimensions’ of a habitat: physical, informational......, and pragmatic, 2) proposes a notation, and 3) sketches a method and exemplifies areas of application using authentic cases from hospital work, primary school education, the maritime domain, and other areas...

  12. Maximum spoutable bed height of spout-fluid bed

    Energy Technology Data Exchange (ETDEWEB)

    Wenqi Zhong; Mingyao Zhang; Baosheng Jin [Southeast University, Nanjing (China). Key Laboratory on Clean Coal Power Generation and Combustion Technology of Ministry of Education

    2006-11-15

    Experimental study on the maximum spoutable bed height of a spout-fluid bed (cross-section of 0.3 m x 0.03 m and height of 2 m) packed with Geldart group D particles has been carried out. The effects of particle size, spout nozzle size and fluidizing gas flow rate on the maximum spoutable bed height were studied. Experimental data were compared to some published experiments and predictions. The results show that the maximum spoutable bed height of spout-fluid bed decreases with increasing particle size and spout nozzle size, which appears the same trend to that of spouted beds. The increasing of fluidizing gas flow rate leads to a sharply decrease in the maximum spoutable bed height. The existent correlations of the maximum spoutable bed height in the literature were observed to involve large discrepancies. Additionally, the flow characteristics when bed materials deeper than the maximum spoutable height were summarized. Under this condition, the spout-fluid bed operated without a stable and coherent spout or fountain assembles the characteristics of jetting fluidized bed. Besides, the mechanisms of spout termination were investigated. It was found that slugging in the spout and growth of instabilities would cause the spout termination in spout-fluid bed.

  13. Spider management in agroecosystems: Habitat manipulation

    Science.gov (United States)

    Mansour, Fadel; Richman, David B.; Whitcomb, W. H.

    1983-01-01

    Based on the literature and on work conducted in Israel, the management of spider populations through habitat manipulation was found to be very helpful in controlling pest insects in various crops. Spiders were found to be reduced or eliminated by non-selective insecticides, although some resistance has been noted

  14. Biomass ash - bed material interactions leading to agglomeration in fluidised bed combustion and gasification

    Energy Technology Data Exchange (ETDEWEB)

    Visser, H.J.M.; Hofmans, H.; Huijnen, R.; Kastelein, R.; Kiel, J.H.A. [ECN Biomass, Petten (Netherlands)

    2000-07-01

    The present study has been aimed at improving the fundamental understanding of mechanisms underlying agglomeration and defluidisation in fluidised bed combustion and gasification of biomass and waste. To this purpose dedicated lab-scale static heating and fluidisation experiments have been conducted with carefully selected and prepared ashes and bed materials, viz. straw ash/sand and willow ash/sand mixtures, mullite subjected to straw gasification and artificially coated mullite. The main conclusion is that ash/bed material interaction processes are very important and often determine the bed agglomeration and defluidisation tendency. In the static heating experiments with both ash/sand mixtures, partial melting-segregation of ash components and dissolution/reaction with the bed material are processes that determine the melt composition. This melt composition and behaviour can deviate considerably form expectations based on ash-only data. Artificially coated bed materials prove to be very useful for systematic studies on the influence of coating composition and thickness on agglomeration tendency. For the coated mullite samples, different stages in the defluidisation process are identified and the influence of coating properties (thickness, composition, morphology) and operating parameters is elucidated. The behaviour of the mullite appears to be dominated by a remnant glass phase. On the one hand, this glass phase accounts for an alkali-getter capability, while on the other hand it is mainly responsible for agglomeration at temperatures {>=} 800C. 3 refs.

  15. Foraging range, habitat use and minimum flight distances of East Atlantic Light-bellied Brent Geese Branta bernicla hrota in their spring staging areas

    DEFF Research Database (Denmark)

    Clausen, Kevin Kuhlmann; Clausen, Preben; Hounisen, Jens Peder;

    2013-01-01

    related to differences in habitat use. Geese using a high proportion of agricultural areas flew greater distances than those avoiding this habitat. Compared to historical data on the same population, these findings indicate a significant enlargement of foraging ranges and increased use of terrestrial...... habitats. This might reflect changes in habitat availability, and is probably related to significant declines in Common Eelgrass Zostera marina in both these areas. From a historically rather sedentary lifestyle, which centred around foraging on Zostera beds in fjord habitats, this population now feeds...... habitat use is associated with increased energetic costs in the form of higher minimum flight distances....

  16. Seaweed farming and artisanal fisheries in an Indonesian seagrass bed - complementary or competitive usages?

    OpenAIRE

    Blankenhorn, Sven Uli

    2008-01-01

    In Indonesia, coastal villages traditionally depend on artisanal fisheries. Increasing population density and fishing pressure make alternative sources of income become more important. One possibility is seaweed farming, which has been introduced in many communities. There, algae farming is restricted to shallow waters and their natural ecosystems, e. g. seagrass beds. Seagrass beds themselves are important habitats for many fish species are the basis for fisheries. If seaweed farming causes ...

  17. Geomechanics of bedded salt

    Energy Technology Data Exchange (ETDEWEB)

    Serata, S.; Milnor, S.W.

    1979-06-08

    Creep data from the literature search is reinterpreted by SGI, resulting in a better understanding of the temperature and stress state dependence of the octahedral creep rate and the octahedral shear strength. The concept of a transition strength between the elastic and the plastic states is in agreement with the data. The elastic and rheological properties of salt are described, and a set of constitutive equations is presented. The dependence of material properties on parameters such as temperature is considered. Findings on the permeability of salt are summarized, and the in-situ behavior of openings in bedded salt is described based on extensive engineering experience. A stress measuring system utilizing a finite element computer code is discussed. Geological factors affecting the stability of salt openings are considered, and the Stress Control Technique for designing stable openings in bedded salt formations is explained.

  18. Geomechanics of bedded salt

    International Nuclear Information System (INIS)

    Creep data from the literature search is reinterpreted by SGI, resulting in a better understanding of the temperature and stress state dependence of the octahedral creep rate and the octahedral shear strength. The concept of a transition strength between the elastic and the plastic states is in agreement with the data. The elastic and rheological properties of salt are described, and a set of constitutive equations is presented. The dependence of material properties on parameters such as temperature is considered. Findings on the permeability of salt are summarized, and the in-situ behavior of openings in bedded salt is described based on extensive engineering experience. A stress measuring system utilizing a finite element computer code is discussed. Geological factors affecting the stability of salt openings are considered, and the Stress Control Technique for designing stable openings in bedded salt formations is explained

  19. Area C borrow Site Habitat Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Sackschewsky, Michael R.; Downs, Janelle L.

    2009-12-04

    A habitat quality assessment was performed within selected portions of the proposed Area C Borrow Source. The previously identified Bitterbrush / Indian ricegrass stabilized dune element occurrence was determined to be better described as a sagebrush /needle-and-thread grass element occurrence of fair to good quality. A new habitat polygon is suggested adjacent to this element occurrence, which would also be sagebrush/needle-and-thread grass, but of poor quality. The proposed site of initial borrow site development was found to be a very low quality community dominated by cheatgrass.

  20. Anopheline larval habitats seasonality and species distribution: a prerequisite for effective targeted larval habitats control programmes.

    Directory of Open Access Journals (Sweden)

    Eliningaya J Kweka

    Full Text Available BACKGROUND: Larval control is of paramount importance in the reduction of malaria vector abundance and subsequent disease transmission reduction. Understanding larval habitat succession and its ecology in different land use managements and cropping systems can give an insight for effective larval source management practices. This study investigated larval habitat succession and ecological parameters which influence larval abundance in malaria epidemic prone areas of western Kenya. METHODS AND FINDINGS: A total of 51 aquatic habitats positive for anopheline larvae were surveyed and visited once a week for a period of 85 weeks in succession. Habitats were selected and identified. Mosquito larval species, physico-chemical parameters, habitat size, grass cover, crop cycle and distance to nearest house were recorded. Polymerase chain reaction revealed that An. gambiae s.l was the most dominant vector species comprised of An.gambiae s.s (77.60% and An.arabiensis (18.34%, the remaining 4.06% had no amplification by polymerase chain reaction. Physico-chemical parameters and habitat size significantly influenced abundance of An. gambiae s.s (P = 0.024 and An. arabiensis (P = 0.002 larvae. Further, larval species abundance was influenced by crop cycle (P≤0.001, grass cover (P≤0.001, while distance to nearest houses significantly influenced the abundance of mosquito species larvae (r = 0.920;P≤0.001. The number of predator species influenced mosquito larval abundance in different habitat types. Crop weeding significantly influenced with the abundance of An.gambiae s.l (P≤0.001 when preceded with fertilizer application. Significantly higher anopheline larval abundance was recorded in habitats in pasture compared to farmland (P = 0.002. When habitat stability and habitat types were considered, hoof print were the most productive followed by disused goldmines. CONCLUSION: These findings suggest that implementation of effective larval

  1. Satellite-based remote sensing of running water habitats at large riverscape scales: Tools to analyze habitat heterogeneity for river ecosystem management

    Science.gov (United States)

    Hugue, F.; Lapointe, M.; Eaton, B. C.; Lepoutre, A.

    2016-01-01

    We illustrate an approach to quantify patterns in hydraulic habitat composition and local heterogeneity applicable at low cost over very large river extents, with selectable reach window scales. Ongoing developments in remote sensing and geographical information science massively improve efficiencies in analyzing earth surface features. With the development of new satellite sensors and drone platforms and with the lowered cost of high resolution multispectral imagery, fluvial geomorphology is experiencing a revolution in mapping streams at high resolution. Exploiting the power of aerial or satellite imagery is particularly useful in a riverscape research framework (Fausch et al., 2002), where high resolution sampling of fluvial features and very large coverage extents are needed. This study presents a satellite remote sensing method that requires very limited field calibration data to estimate over various scales ranging from 1 m to many tens or river kilometers (i) spatial composition metrics for key hydraulic mesohabitat types and (ii) reach-scale wetted habitat heterogeneity indices such as the hydromorphological index of diversity (HMID). When the purpose is hydraulic habitat characterization applied over long river networks, the proposed method (although less accurate) is much less computationally expensive and less data demanding than two dimensional computational fluid dynamics (CFD). Here, we illustrate the tools based on a Worldview 2 satellite image of the Kiamika River, near Mont Laurier, Quebec, Canada, specifically over a 17-km river reach below the Kiamika dam. In the first step, a high resolution water depth (D) map is produced from a spectral band ratio (calculated from the multispectral image), calibrated with limited field measurements. Next, based only on known river discharge and estimated cross section depths at time of image capture, empirical-based pseudo-2D hydraulic rules are used to rapidly generate a two-dimensional map of flow velocity

  2. Gravel-bed river floodplains are the ecological nexus of glaciated mountain landscapes.

    Science.gov (United States)

    Hauer, F Richard; Locke, Harvey; Dreitz, Victoria J; Hebblewhite, Mark; Lowe, Winsor H; Muhlfeld, Clint C; Nelson, Cara R; Proctor, Michael F; Rood, Stewart B

    2016-06-01

    Gravel-bed river floodplains in mountain landscapes disproportionately concentrate diverse habitats, nutrient cycling, productivity of biota, and species interactions. Although stream ecologists know that river channel and floodplain habitats used by aquatic organisms are maintained by hydrologic regimes that mobilize gravel-bed sediments, terrestrial ecologists have largely been unaware of the importance of floodplain structures and processes to the life requirements of a wide variety of species. We provide insight into gravel-bed rivers as the ecological nexus of glaciated mountain landscapes. We show why gravel-bed river floodplains are the primary arena where interactions take place among aquatic, avian, and terrestrial species from microbes to grizzly bears and provide essential connectivity as corridors for movement for both aquatic and terrestrial species. Paradoxically, gravel-bed river floodplains are also disproportionately unprotected where human developments are concentrated. Structural modifications to floodplains such as roads, railways, and housing and hydrologic-altering hydroelectric or water storage dams have severe impacts to floodplain habitat diversity and productivity, restrict local and regional connectivity, and reduce the resilience of both aquatic and terrestrial species, including adaptation to climate change. To be effective, conservation efforts in glaciated mountain landscapes intended to benefit the widest variety of organisms need a paradigm shift that has gravel-bed rivers and their floodplains as the central focus and that prioritizes the maintenance or restoration of the intact structure and processes of these critically important systems throughout their length and breadth. PMID:27386570

  3. Gravel-bed river floodplains are the ecological nexus of glaciated mountain landscapes.

    Science.gov (United States)

    Hauer, F Richard; Locke, Harvey; Dreitz, Victoria J; Hebblewhite, Mark; Lowe, Winsor H; Muhlfeld, Clint C; Nelson, Cara R; Proctor, Michael F; Rood, Stewart B

    2016-06-01

    Gravel-bed river floodplains in mountain landscapes disproportionately concentrate diverse habitats, nutrient cycling, productivity of biota, and species interactions. Although stream ecologists know that river channel and floodplain habitats used by aquatic organisms are maintained by hydrologic regimes that mobilize gravel-bed sediments, terrestrial ecologists have largely been unaware of the importance of floodplain structures and processes to the life requirements of a wide variety of species. We provide insight into gravel-bed rivers as the ecological nexus of glaciated mountain landscapes. We show why gravel-bed river floodplains are the primary arena where interactions take place among aquatic, avian, and terrestrial species from microbes to grizzly bears and provide essential connectivity as corridors for movement for both aquatic and terrestrial species. Paradoxically, gravel-bed river floodplains are also disproportionately unprotected where human developments are concentrated. Structural modifications to floodplains such as roads, railways, and housing and hydrologic-altering hydroelectric or water storage dams have severe impacts to floodplain habitat diversity and productivity, restrict local and regional connectivity, and reduce the resilience of both aquatic and terrestrial species, including adaptation to climate change. To be effective, conservation efforts in glaciated mountain landscapes intended to benefit the widest variety of organisms need a paradigm shift that has gravel-bed rivers and their floodplains as the central focus and that prioritizes the maintenance or restoration of the intact structure and processes of these critically important systems throughout their length and breadth.

  4. Gravel-bed river floodplains are the ecological nexus of glaciated mountain landscapes

    Science.gov (United States)

    Hauer, F. Richard; Locke, Harvey; Dreitz, Victoria; Hebblewhite, Mark; Lowe, Winsor; Muhlfeld, Clint C.; Nelson, Cara; Proctor, Michael F; Rood, Stewart B.

    2016-01-01

    Gravel-bed river floodplains in mountain landscapes disproportionately concentrate diverse habitats, nutrient cycling, productivity of biota, and species interactions. Although stream ecologists know that river channel and floodplain habitats used by aquatic organisms are maintained by hydrologic regimes that mobilize gravel-bed sediments, terrestrial ecologists have largely been unaware of the importance of floodplain structures and processes to the life requirements of a wide variety of species. We provide insight into gravel-bed rivers as the ecological nexus of glaciated mountain landscapes. We show why gravel-bed river floodplains are the primary arena where interactions take place among aquatic, avian, and terrestrial species from microbes to grizzly bears and provide essential connectivity as corridors for movement for both aquatic and terrestrial species. Paradoxically, gravel-bed river floodplains are also disproportionately unprotected where human developments are concentrated. Structural modifications to floodplains such as roads, railways, and housing and hydrologicaltering hydroelectric or water storage dams have severe impacts to floodplain habitat diversity and productivity, restrict local and regional connectivity, and reduce the resilience of both aquatic and terrestrial species, including adaptation to climate change. To be effective, conservation efforts in glaciated mountain landscapes intended to benefit the widest variety of organisms need a paradigm shift that has gravel-bed rivers and their floodplains as the central focus and that prioritizes the maintenance or restoration of the intact structure and processes of these critically important systems throughout their length and breadth.

  5. Gravel-bed river floodplains are the ecological nexus of glaciated mountain landscapes

    Science.gov (United States)

    Hauer, F. Richard; Locke, Harvey; Dreitz, Victoria J.; Hebblewhite, Mark; Lowe, Winsor H.; Muhlfeld, Clint C.; Nelson, Cara R.; Proctor, Michael F.; Rood, Stewart B.

    2016-01-01

    Gravel-bed river floodplains in mountain landscapes disproportionately concentrate diverse habitats, nutrient cycling, productivity of biota, and species interactions. Although stream ecologists know that river channel and floodplain habitats used by aquatic organisms are maintained by hydrologic regimes that mobilize gravel-bed sediments, terrestrial ecologists have largely been unaware of the importance of floodplain structures and processes to the life requirements of a wide variety of species. We provide insight into gravel-bed rivers as the ecological nexus of glaciated mountain landscapes. We show why gravel-bed river floodplains are the primary arena where interactions take place among aquatic, avian, and terrestrial species from microbes to grizzly bears and provide essential connectivity as corridors for movement for both aquatic and terrestrial species. Paradoxically, gravel-bed river floodplains are also disproportionately unprotected where human developments are concentrated. Structural modifications to floodplains such as roads, railways, and housing and hydrologic-altering hydroelectric or water storage dams have severe impacts to floodplain habitat diversity and productivity, restrict local and regional connectivity, and reduce the resilience of both aquatic and terrestrial species, including adaptation to climate change. To be effective, conservation efforts in glaciated mountain landscapes intended to benefit the widest variety of organisms need a paradigm shift that has gravel-bed rivers and their floodplains as the central focus and that prioritizes the maintenance or restoration of the intact structure and processes of these critically important systems throughout their length and breadth. PMID:27386570

  6. Habitats and Foraging Movements of Larvae of Molanna uniophila Vorhies (Trichoptera: Molannidae in Pratt Lake, Michigan, USA

    Directory of Open Access Journals (Sweden)

    Neal D. Mundahl

    2015-01-01

    Full Text Available Habitats and foraging movements of larvae of Molanna uniophila Vorhies (Trichoptera: Molannidae were studied during four summers in Pratt Lake, Michigan. Larvae lived and fed in shallow (<10 cm, sand-bottomed lake margins, where macrophyte densities ranged from 86 to 452 stems/m2. Average densities of larvae varied fivefold between years (2.7 versus 13.6 individuals/m2, but larval densities did not vary significantly between habitat patches with low (120 stems/m2 and high (360 stems/m2 macrophyte densities. Larvae and their cases exhibited strong patterns of simple, linear growth. Diets of larvae were dominated by amorphous detritus, plant debris, diatoms, and filamentous algae, but midges, cladocerans, and other microscopic aquatic animals also were consumed. Larvae shifted their bodies and cases forward across the surface sediments up to 4 times/minute while foraging, moving as much as 2.5 m/hour. Movements and distances traveled while feeding increased significantly with increased water temperatures, peaking during midafternoon hours. Distances moved by feeding larvae did not differ between habitats with low versus high macrophyte densities. Larvae foraged most actively during daylight hours and did not selectively utilize macrophyte beds as partial refugia from potential predators while feeding.

  7. Tucannon Stream/Riparian Restoration : Fiscal Year 1998 Habitat Projects.

    Energy Technology Data Exchange (ETDEWEB)

    Bruegman, Terry; Nordheim, Debbie

    1999-01-01

    In 1993 the Tucannon River was selected by the Bonneville Power Administration to be one of the three Washington Model Watersheds. This plan was developed to identify, protect, and restore fish habitat by utilizing sound technical information and citizen input.

  8. Exercise countermeasures for bed-rest deconditioning

    Science.gov (United States)

    Greenleaf, John (Editor)

    1993-01-01

    The purpose for this 30-day bed rest study was to investigate the effects of short-term, high intensity isotonic and isokinetic exercise training on maintenance of working capacity (peak oxygen uptake), muscular strength and endurance, and on orthostatic tolerance, posture and gait. Other data were collected on muscle atrophy, bone mineralization and density, endocrine analyses concerning vasoactivity and fluid-electrolyte balance, muscle intermediary metabolism, and on performance and mood of the subjects. It was concluded that: The subjects maintained a relatively stable mood, high morale, and high esprit de corps throughout the study. Performance improved in nearly all tests in almost all the subjects. Isotonic training, as opposed to isokinetic exercise training, was associated more with decreasing levels of psychological tension, concentration, and motivation; and improvement in the quality of sleep. Working capacity (peak oxygen uptake) was maintained during bed rest with isotonic exercise training; it was not maintained with isokinetic or no exercise training. In general, there was no significant decrease in strength or endurance of arm or leg muscles during bed rest, in spite of some reduction in muscle size (atrophy) of some leg muscles. There was no effect of isotonic exercise training on orthostasis, since tilt-table tolerance was reduced similarly in all three groups following bed rest. Bed rest resulted in significant decreases of postural stability and self-selected step length, stride length, and walking velocity, which were not influenced by either exercise training regimen. Most pre-bed rest responses were restored by the fourth day of recovery.

  9. Spatial hierarchical geomorphic controls on salmonid spawning habitat: using geomorphic parameters to set ecological status targets

    Science.gov (United States)

    Moir, H. J.

    2009-12-01

    To set river restoration targets or identifying ‘reference condition’ benchmarks, the ‘ecological status’ of river systems is often subjectively based on how humans perceive a non-impacted river should look. Rarely are these objectives based on an explicit understanding of how physical conditions provide the habitats required by instream biota to optimally complete their life cycles. Furthermore, although much research acknowledges the spatial hierarchical physical controls on instream habitats, there is little attempt to integrate across scales while explicitly linking key aspects of instream ecology to geomorphic form and process. This paper describes the physical controls on salmon (Atlantic and Chinook) spawning habitat across a range of spatial scales (basin - reach - meso - micro). Over the past five decades much work has been conducted describing the micro-habitat (typically depth, velocity and substrate) of spawning salmonids. However, this not accounted for the implicit inter-relationships between these basic habitat variables in rivers. It is demonstrated that the specific micro-scale physical conditions selected by salmonids reflect the intersection of biotic requirements with geomorphic processes that produce specific joint hydraulic-sedimentary patterns. At the next, meso-scale, different morphological units (e.g. pools, riffles) provide contrasting joint hydraulic and sedimentary relationships that intersect to varying degrees with micro-habitat requirements, producing unit types that are used more or less frequently. Morphology also exerts a strong control on the distribution of hydraulics across a meso-scale unit under varying flow. Thus, some morphologies provide more ‘stable’ habitat conditions as discharge changes. Furthermore, the proximity of spawning units to other units that provide adult holding/ resting habitat (e.g. pools) is also shown to be an important meso-scale control. Over longer time scales, prevailing fluvial forces

  10. Self-repairing composite walls for pressurized space habitats

    Science.gov (United States)

    Dry, Carolyn

    2016-04-01

    A most important factor for human occupied habitats in space is to ensure that the pressurized habitat does not lose pressure catastrophically by the penetration of space debris or micrometeorites through the wall and into the pressurized space. Regenerative self repairing composites used for the space station habitat to prevent loss of pressure was demonstrated in tests The wall sample had ambient pressurized on one side with vacuum on the other, then was punctured all the way through; the pressure reading went from -26 inches of mercury to -26 inches and stayed there indefinitely. There was no loss of pressure! This will be a game changer for space habitat design. This represents a proposed test bed experimental effort on the International Space Station for self repairing regenerative walls of pressurized habitats, supported by significant puncture over vacuum and puncture testing performed to date, which will provide NASA with an innovative new light weight multi-hit superior Astronaut Protective Wall solution for pressurized space habitats.

  11. Porosity, single-phase permeability, and capillary pressure data from preliminary laboratory experiments on selected samples from Marker Bed 139 at the Waste Isolation Pilot Plant. Volume 3 of 3: Appendices C, D, E, and F

    Energy Technology Data Exchange (ETDEWEB)

    Howarth, S.M.; Christian-Frear, T.

    1997-08-01

    This volume contains the mineralogy, porosity, and permeability results from the Marker Bed 139 anhydrite specimens evaluated by TerraTek, Inc. for the Waste Isolation Pilot Plant. This volume also documents the brine recipe used by RE/SPEC, Inc., the parameter package submitted to Performance Assessment based on all the data, and a memo on the mixed Brooks and Corey two-phase characteristic curves.

  12. Bed Rest Muscular Atrophy

    Science.gov (United States)

    Greenleaf, John E.

    2000-01-01

    A major debilitating response from prolonged bed rest (BR) is muscle atrophy, defined as a "decrease in size of a part of tissue after full development has been attained: a wasting away of tissue as from disuse, old age, injury or disease". Part of the complicated mechanism for the dizziness, increased body instability, and exaggerated gait in patients who arise immediately after BR may be a result of not only foot pain, but also of muscular atrophy and associated reduction in lower limb strength. Also, there seems to be a close association between muscle atrophy and bone atrophy. A discussion of many facets of the total BR homeostatic syndrome has been published. The old adage that use determines form which promotes function of bone (Wolff's law) also applies to those people exposed to prolonged BR (without exercise training) in whom muscle atrophy is a consistent finding. An extreme case involved a 16-year-old boy who was ordered to bed by his mother in 1932: after 50 years in bed he had "a lily-white frame with limbs as thin as the legs of a ladder-back chair". These findings emphasize the close relationship between muscle atrophy and bone atrophy. In addition to loss of muscle mass during deconditioning, there is a significant loss of muscle strength and a decrease in protein synthesis. Because the decreases in force (strength) are proportionately greater than those in fiber size or muscle cross-sectional area, other contributory factors must be involved; muscle fiber dehydration may be important.

  13. Coal Bed Methane Primer

    Energy Technology Data Exchange (ETDEWEB)

    Dan Arthur; Bruce Langhus; Jon Seekins

    2005-05-25

    During the second half of the 1990's Coal Bed Methane (CBM) production increased dramatically nationwide to represent a significant new source of income and natural gas for many independent and established producers. Matching these soaring production rates during this period was a heightened public awareness of environmental concerns. These concerns left unexplained and under-addressed have created a significant growth in public involvement generating literally thousands of unfocused project comments for various regional NEPA efforts resulting in the delayed development of public and fee lands. The accelerating interest in CBM development coupled to the growth in public involvement has prompted the conceptualization of this project for the development of a CBM Primer. The Primer is designed to serve as a summary document, which introduces and encapsulates information pertinent to the development of Coal Bed Methane (CBM), including focused discussions of coal deposits, methane as a natural formed gas, split mineral estates, development techniques, operational issues, producing methods, applicable regulatory frameworks, land and resource management, mitigation measures, preparation of project plans, data availability, Indian Trust issues and relevant environmental technologies. An important aspect of gaining access to federal, state, tribal, or fee lands involves education of a broad array of stakeholders, including land and mineral owners, regulators, conservationists, tribal governments, special interest groups, and numerous others that could be impacted by the development of coal bed methane. Perhaps the most crucial aspect of successfully developing CBM resources is stakeholder education. Currently, an inconsistent picture of CBM exists. There is a significant lack of understanding on the parts of nearly all stakeholders, including industry, government, special interest groups, and land owners. It is envisioned the Primer would being used by a variety of

  14. Bed form dynamics in distorted lightweight scale models

    Science.gov (United States)

    Aberle, Jochen; Henning, Martin; Ettmer, Bernd

    2016-04-01

    The adequate prediction of flow and sediment transport over bed forms presents a major obstacle for the solution of sedimentation problems in alluvial channels because bed forms affect hydraulic resistance, sediment transport, and channel morphodynamics. Moreover, bed forms can affect hydraulic habitat for biota, may introduce severe restrictions to navigation, and present a major problem for engineering structures such as water intakes and groynes. The main body of knowledge on the geometry and dynamics of bed forms such as dunes originates from laboratory and field investigations focusing on bed forms in sand bed rivers. Such investigations enable insight into the physics of the transport processes, but do not allow for the long term simulation of morphodynamic development as required to assess, for example, the effects of climate change on river morphology. On the other hand, this can be achieved through studies with distorted lightweight scale models allowing for the modification of the time scale. However, our understanding of how well bed form geometry and dynamics, and hence sediment transport mechanics, are reproduced in such models is limited. Within this contribution we explore this issue using data from investigations carried out at the Federal Waterways and Research Institute in Karlsruhe, Germany in a distorted lightweight scale model of the river Oder. The model had a vertical scale of 1:40 and a horizontal scale of 1:100, the bed material consisted of polystyrene particles, and the resulting dune geometry and dynamics were measured with a high spatial and temporal resolution using photogrammetric methods. Parameters describing both the directly measured and up-scaled dune geometry were determined using the random field approach. These parameters (e.g., standard deviation, skewness, kurtosis) will be compared to prototype observations as well as to results from the literature. Similarly, parameters describing the lightweight bed form dynamics, which

  15. Earth is a Marine Habitat. Habitat Conservation Program.

    Science.gov (United States)

    National Oceanic and Atmospheric Administration (DOC), Rockville, MD.

    This brochure is intended to educate the public about the need to conserve and preserve the earth's environment (man's habitat). It contains an introduction to the ocean world and threats to coastal habitat. Photos and narrative revolve around the theme "Earth is a Marine Habitat." Sections include: "The Web of Life,""Oceans and the United…

  16. NEPR Benthic Habitat Map 2015

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This benthic habitat map was created from a semi-automated habitat mapping process, using a combination of bathymetry, satellite imagery, aerial imagery and...

  17. Habitat Evaluation Procedures (HEP) Report; Gamblin Lake, Technical Report 2005.

    Energy Technology Data Exchange (ETDEWEB)

    Entz, Ray

    2005-05-01

    On August 12, 2003, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Gamblin Lake property, an acquisition completed by the Kalispel Tribe of Indians in December 2002. Evaluation species and appropriate models include bald eagle, black-capped chickadee, mallard, muskrat, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Gamblin Lake Project provides a total of 273.28 Habitat Units (HUs) for the species evaluated. Conifer forest habitat provides 127.92 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. Forested wetland habitat provides 21.06 HUs for bald eagle, black-caped chickadee, mallard, and white-tailed deer. Wet meadow provides 78.05 HUs for Canada goose and mallard. Emergent wetland habitat provides 46.25 HUs for mallard, muskrat, and Canada goose. The objective of using HEP at the Gamblin Lake Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

  18. Habitat Evaluation Procedures (HEP) Report; Beaver Lake, Technical Report 2005.

    Energy Technology Data Exchange (ETDEWEB)

    Entz, Ray

    2005-05-01

    On August 14, 2003, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Beaver Lake property, an acquisition completed by the Kalispel Tribe of Indians in November 2002. Evaluation species and appropriate models include bald eagle, black-capped chickadee, Canada goose, mallard, muskrat, yellow warbler, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Beaver Lake Project provides a total of 232.26 Habitat Units (HUs) for the species evaluated. Conifer forest habitat provides 136.58 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. Forested wetland habitat provides 20.02 HUs for bald eagle, black-caped chickadee, mallard, and white-tailed deer. Scrub-shrub wetland habitat provides 7.67 HUs for mallard, yellow warbler, and white-tailed deer. Grassland meadow provides 22.69 HUs for Canada goose and mallard. Emergent wetlands provide 35.04 HUs for Canada goose, mallard, and muskrat. Open water provided 10.26 HUs for Canada goose, mallard, and muskrat. The objective of using HEP at the Beaver Lake Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

  19. Steady-state thermal-hydraulic of pebble bed blanket on hybrid reactor

    International Nuclear Information System (INIS)

    This paper gives thermal-hydraulic studies of pebble bed blanket on Hybrid Reactor. The concept of whole pebble bed blanket and the cooling methods are presented. The thermal-hydraulic characteristics of pebble bed are summarized. The theoretical model and code for solving heat transfer and flowing are presented. By using this code the calculation and analysis of thermal hydraulic of pebble bed Blanket of Hybrid Reactor are also given. In order to improve the flexibility, safety and economy, the authors select pebble beds not only to breed Tritium, but also to breed fission material and to multiply neutron. 5 MPa Helium is used as coolant and 0.05 MPa-0.1 MPa Helium is used as Purge gas. The heat transfer mechanisms of pebble bed are very complicated which include conduction, convection and radiation. In order to study the thermal-hydraulic of the bed, the authors just simply consider it as homogeneous and continuous binary phase medium as that used in the porous medium at the condition that the size of the bed is much greater than that of the balls. The coolant or the purge gas flowing through the bed is just considered existing a cooling source in the bed. It also significantly influences the effective conductivity's of the bed. Porous fraction, the main factor of the bed depends on the geometry position and parameters. From this model, one can obtain the thermal-hydraulic governing equations of the bed

  20. Habitat Use Database - Groundfish Essential Fish Habitat (EFH) Habitat Use Database (HUD)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Habitat Use Database (HUD) was specifically designed to address the need for habitat-use analyses in support of groundfish EFH, HAPCs, and fishing and...

  1. Old river beds under urbanization pressure. Can we protect valuable aquatic ecosystems within the cities?

    Science.gov (United States)

    Sikorska, Daria; Sikorski, Piotr

    2016-04-01

    Old river channels are valuable ecosystems in the scale of whole Europe. Protected as Natura 2000 habitats they are characterized by high biodiversity and provide various ecosystem services. River regulation, eutrophication or lack of annual flooding result in an impoverishment and disappearance of these habitats. Moreover they are subjected to severe pressure from uncontrolled expansion of the cities. The aim of this study was to determine factors associated with urbanization mostly contributing to impoverishment of the vegetation associated with the old channels and to identify landscape characteristics favouring high diversity and naturalness. We were seeking for indices that could be implemented in spatial management for preservation of these ecosystems. Vegetation inventory of 28 lakes, being former river Vistula beds near Warsaw was held. The lakes were located in an urban-rural gradient from the city centre, suburban zone to rural areas. Mapping of vegetation was performed for aquatic vegetation, rushes and vegetation of the shores (321 relevés). Human pressure was assessed on the basis of landscape composition of the lakes neighbourhood, characteristic features of the reservoir and water physio-chemical properties. High diversity and naturalness of the vegetation associated with former Vistula River beds was proved. Effects of the human pressure in the vegetation composition were recognized in high share of alien species and impoverishment of native plants. Composition was dependant on the intensity of human pressure in the neighbourhood and was mostly related to percentage of built-up areas and road density. Selected measures allowed to explain not more than 30% of plants composition variation which implies strong effect of local factors. Vegetation composition of former river beds changed significantly along urban-rural gradient, though the trend could be noted only to the city border. Several protection activities were proposed favouring high

  2. Variability of bed drag on cohesive beds under wave action

    Science.gov (United States)

    Safak, Ilgar

    2016-01-01

    Drag force at the bed acting on water flow is a major control on water circulation and sediment transport. Bed drag has been thoroughly studied in sandy waters, but less so in muddy coastal waters. The variation of bed drag on a muddy shelf is investigated here using field observations of currents, waves, and sediment concentration collected during moderate wind and wave events. To estimate bottom shear stress and the bed drag coefficient, an indirect empirical method of logarithmic fitting to current velocity profiles (log-law), a bottom boundary layer model for combined wave-current flow, and a direct method that uses turbulent fluctuations of velocity are used. The overestimation by the log-law is significantly reduced by taking turbulence suppression due to sediment-induced stratification into account. The best agreement between the model and the direct estimates is obtained by using a hydraulic roughness of 10  m in the model. Direct estimate of bed drag on the muddy bed is found to have a decreasing trend with increasing current speed, and is estimated to be around 0.0025 in conditions where wave-induced flow is relatively weak. Bed drag shows an increase (up to fourfold) with increasing wave energy. These findings can be used to test the bed drag parameterizations in hydrodynamic and sediment transport models and the skills of these models in predicting flows in muddy environments.

  3. Habitat monitoring needs for Arapaho NWR

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is the refuge's ideas on what level of monitoring is needed for each habitat objective. Habitat objectives include riparian habitat, wetland habitat,...

  4. Hidden Forests: The role of vegetated coastal habitats in the ocean carbon budget (Vladimir Ivanovich Vernadsky Medal Lecture)

    Science.gov (United States)

    Duarte, Carlos M.

    2016-04-01

    Vegetated coastal habitats, including mangrove forests, salt-marshes, seagrass meadows and macroalgal beds, provide the marine equivalent to terrestrial forests. However, in contrast to the traditional recognition of forests as significant components of the global carbon budget, the biogeochemical significance of vegetated coastal habitats has been largely ignored. However, the past decade has witness a paradigm shift, where vegetated coastal habitats have been recognized to play a globally significant role in the carbon budget of the ocean. Here I synthesize this evidence and consider how current representations of the ocean carbon budget need be reconsidered to incorporate the role of vegetated coastal habitats and globally relevant, sites of intense carbon cycling.

  5. LSP Composite Test Bed Design

    Science.gov (United States)

    Day, Arthur C.; Griess, Kenneth H.

    2013-01-01

    This document provides standalone information for the Lightning Strike Protection (LSP) Composite Substrate Test Bed Design. A six-sheet drawing set is reproduced for reference, as is some additional descriptive information on suitable sensors and use of the test bed.

  6. Summary of Bed-Sediment Measurements Along the Platte River, Nebraska, 1931-2009

    Science.gov (United States)

    Kinzel, P.J.; Runge, J.T.

    2010-01-01

    Rivers are conduits for water and sediment supplied from upstream sources. The sizes of the sediments that a river bed consists of typically decrease in a downstream direction because of natural sorting. However, other factors can affect the caliber of bed sediment including changes in upstream water-resource development, land use, and climate that alter the watershed yield of water or sediment. Bed sediments provide both a geologic and stratigraphic record of past fluvial processes and quantification of current sediment transport relations. The objective of this fact sheet is to describe and compare longitudinal measurements of bed-sediment sizes made along the Platte River, Nebraska from 1931 to 2009. The Platte River begins at the junction of the North Platte and South Platte Rivers near North Platte, Nebr. and flows east for approximately 500 kilometers before joining the Missouri River at Plattsmouth, Nebr. The confluence of the Loup River with the Platte River serves to divide the middle (or central) Platte River (the Platte River upstream from the confluence with the Loup River) and lower Platte River (the Platte River downstream from the confluence with Loup River). The Platte River provides water for a variety of needs including: irrigation, infiltration to public water-supply wells, power generation, recreation, and wildlife habitat. The Platte River Basin includes habitat for four federally listed species including the whooping crane (Grus americana), interior least tern (Sterna antillarum), piping plover (Charadrius melodus), and pallid sturgeon (Scaphirhynchus albus). A habitat recovery program for the federally listed species in the Platte River was initiated in 2007. One strategy identified by the recovery program to manage and enhance habitat is the manipulation of streamflow. Understanding the longitudinal and temporal changes in the size gradation of the bed sediment will help to explain the effects of past flow regimes and anticipated

  7. Development of a new method for improving load turndown in fluidized bed combustors: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Brown, R.C.

    1988-12-01

    The objective of this research was to investigate a new concept in fluidized bed design that improves load turndown capability. This improvement is accomplished by independently controlling heat transfer and combustion in the combustor. The design consists of two fluidized beds, one central and one annular. The central bed serves as the combustion bed. The annular bed is fluidized separately from the combustion bed and its level of fluidization determine the overall heat transfer rate from the combustion bed to the surrounding water jacket. Early theoretical considerations suggested a load turndown exceeding ten was possible for this design. This research consisted of three major phases: development of a computational model to predict heat transfer in the two-bed combustor, heat transfer measurements in hot-and-cold flow models of the combustor, and combustion tests in an optimally designed combustor. The computation model was useful in selecting the design of the combustor. Annular bed width and particle sizes were chosen with the aid of the model. The heat transfer tests were performed to determine if the existing correlations for fluidized bed heat transfer coefficients were sufficiently accurate for high aspect ratio fluidized beds (such as the annular bed in the combustor). Combustion tests were performed in an optimally designed combustor. Three fuel forms were used: double screened, crushed coal, coal-water-limestone mixtures (CWLM), and coal-limestone briquettes. 18 refs., 30 figs., 8 tabs.

  8. A meta-analysis of lesser prairie-chicken nesting and brood-rearing habitats: implications for habitat management

    Science.gov (United States)

    Hagen, Christian A.; Grisham, Blake A.; Boal, Clint W.; Haukos, David A.

    2013-01-01

    The distribution and range of lesser prairie-chicken (Tympanuchus pallidicinctus) has been reduced by >90% since European settlement of the Great Plains of North America. Currently, lesser prairie-chickens occupy 3 general vegetation communities: sand sagebrush (Artemisia filifolia), sand shinnery oak (Quercus havardii), and mixed-grass prairies juxtaposed with Conservation Reserve Program grasslands. As a candidate for protection under the Endangered Species Act, there is a need for a synthesis that characterizes habitat structure rangewide. Thus, we conducted a meta-analysis of vegetation characteristics at nest sites and brood habitats to determine whether there was an overall effect (Hedges' d) of habitat selection and to estimate average (95% CI) habitat characteristics at use sites. We estimated effect sizes (di) from the difference between use (nests and brood sites) and random sampling sites for each study (n = 14), and derived an overall effect size (d++). There was a general effect for habitat selection as evidenced by low levels of variation in effect sizes across studies and regions. There was a small to medium effect (d++) = 0.20-0.82) of selection for greater vertical structure (visual obstruction) by nesting females in both vegetation communities, and selection against bare ground (d++ = 0.20-0.58). Females with broods exhibited less selectivity for habitat components except for vertical structure. The variation of d++ was greater during nesting than brooding periods, signifying a seasonal shift in habitat use, and perhaps a greater range of tolerance for brood-rearing habitat. The overall estimates of vegetation cover were consistent with those provided in management guidelines for the species.

  9. Seedling stage strategies as a means of habitat specialization in herbaceous plants

    DEFF Research Database (Denmark)

    ten Brink, Dirk-Jan; Bruun, Hans Henrik

    2011-01-01

    specialized to forest vs. open habitats and to dry vs. wet habitats. We also tested whether effects of shade and drought vary independently or, alternatively, if shade may amplify effects on drought-stressed plants. Seedling response in terms of growth rate, height, slenderness, specific leaf area (SLA...... for the moist-habitat species, for which elongation increased with shade. Contrary to our expectations, species from dry habitats grew bigger than species from moist habitats in all treatments. SLA responded to the light treatment, but not to watering regime. The contrasting light and moisture conditions across...... habitats appear to not have selected for differences in SLA. We conclude that seedling phase strategies of resource allocation in temperate herbs contribute to their habitat specialization. Habitat-specific seedling strategies and trade-offs in response to resource availability and environmental conditions...

  10. Paleoecological significance of stable isotope ratios in Miocene tropical shallow marine habitats (Indonesia)

    NARCIS (Netherlands)

    Reich, Sonja; Warter, Viola; Wesselingh, Frank P.; Zwaan, Johannes C.; Lourens, Lucas; Renema, Willem

    2015-01-01

    Seagrass meadows are important shallow-water ecosystems that provide habitat for numerous associated organisms and play a crucial role in nutrient cycling, but their detection in the fossil record is problematic. Indirect indicators are often needed to discriminate seagrass beds from other shallow m

  11. Ecosystem Services of Coastal Habitats and Fisheries: Multi-Scale Ecological and Economic Modeling

    Science.gov (United States)

    Critical habitats for fish and wildlife often are small patches in landscapes, e.g., aquatic vegetation beds, reefs, isolated ponds and wetlands, remnant old growth forests, etc, yet the same animal populations that depend on these patches for reproduction or survival can be exte...

  12. Optimal flow for brown trout: Habitat - prey optimization.

    Science.gov (United States)

    Fornaroli, Riccardo; Cabrini, Riccardo; Sartori, Laura; Marazzi, Francesca; Canobbio, Sergio; Mezzanotte, Valeria

    2016-10-01

    The correct definition of ecosystem needs is essential in order to guide policy and management strategies to optimize the increasing use of freshwater by human activities. Commonly, the assessment of the optimal or minimum flow rates needed to preserve ecosystem functionality has been done by habitat-based models that define a relationship between in-stream flow and habitat availability for various species of fish. We propose a new approach for the identification of optimal flows using the limiting factor approach and the evaluation of basic ecological relationships, considering the appropriate spatial scale for different organisms. We developed density-environment relationships for three different life stages of brown trout that show the limiting effects of hydromorphological variables at habitat scale. In our analyses, we found that the factors limiting the densities of trout were water velocity, substrate characteristics and refugia availability. For all the life stages, the selected models considered simultaneously two variables and implied that higher velocities provided a less suitable habitat, regardless of other physical characteristics and with different patterns. We used these relationships within habitat based models in order to select a range of flows that preserve most of the physical habitat for all the life stages. We also estimated the effect of varying discharge flows on macroinvertebrate biomass and used the obtained results to identify an optimal flow maximizing habitat and prey availability. PMID:27320735

  13. Simulation of seagrass bed mapping by satellite images based on the radiative transfer model

    Science.gov (United States)

    Sagawa, Tatsuyuki; Komatsu, Teruhisa

    2015-06-01

    Seagrass and seaweed beds play important roles in coastal marine ecosystems. They are food sources and habitats for many marine organisms, and influence the physical, chemical, and biological environment. They are sensitive to human impacts such as reclamation and pollution. Therefore, their management and preservation are necessary for a healthy coastal environment. Satellite remote sensing is a useful tool for mapping and monitoring seagrass beds. The efficiency of seagrass mapping, seagrass bed classification in particular, has been evaluated by mapping accuracy using an error matrix. However, mapping accuracies are influenced by coastal environments such as seawater transparency, bathymetry, and substrate type. Coastal management requires sufficient accuracy and an understanding of mapping limitations for monitoring coastal habitats including seagrass beds. Previous studies are mainly based on case studies in specific regions and seasons. Extensive data are required to generalise assessments of classification accuracy from case studies, which has proven difficult. This study aims to build a simulator based on a radiative transfer model to produce modelled satellite images and assess the visual detectability of seagrass beds under different transparencies and seagrass coverages, as well as to examine mapping limitations and classification accuracy. Our simulations led to the development of a model of water transparency and the mapping of depth limits and indicated the possibility for seagrass density mapping under certain ideal conditions. The results show that modelling satellite images is useful in evaluating the accuracy of classification and that establishing seagrass bed monitoring by remote sensing is a reliable tool.

  14. Wall-to-bed heat transfer in circulating fluidized beds

    Energy Technology Data Exchange (ETDEWEB)

    Fox, W.B.; Grewal, N.S.; Moen, D.A. [Univ. of North Dakota, Grand Forks, ND (United States). Mechanical Engineering Dept.

    1999-05-01

    Circulating fluidized beds (CFBs) have become increasingly important in recent years for coal combustion and gas-solid reactions. Here, heat transfer from the wall of a circulating fluidized bed to the fast bed suspension has been investigated for several materials. The range of investigation includes dense and dilute phase fast fluidization and pneumatic transport. The overall heat transfer coefficient was found to be a function mainly of cross-sectional average suspension density. Effects of superficial velocity and solids mass flux were obscured by their interrelationship to the suspension density. Two models from the literature are evaluated using present and published data.

  15. Plant Habitat (PH)

    Science.gov (United States)

    Onate, Bryan

    2016-01-01

    The International Space Station (ISS) will soon have a platform for conducting fundamental research of Large Plants. Plant Habitat (PH) is designed to be a fully controllable environment for high-quality plant physiological research. PH will control light quality, level, and timing, temperature, CO2, relative humidity, and irrigation, while scrubbing ethylene. Additional capabilities include leaf temperature and root zone moisture and oxygen sensing. The light cap will have red (630 nm), blue (450 nm), green (525 nm), far red (730 nm) and broad spectrum white LEDs. There will be several internal cameras (visible and IR) to monitor and record plant growth and operations.

  16. Pulling a patient up in bed

    Science.gov (United States)

    Moving a patient in bed ... You must move or pull someone up in bed the right way to avoid injuring the patient's ... people to safely move a patient up in bed. Friction from rubbing can scrape or tear the ...

  17. Porosity, single-phase permeability, and capillary pressure data from preliminary laboratory experiments on selected samples from Marker Bed 139 at the Waste Isolation Pilot Plant. Volume 1 of 3: Main report, appendix A

    International Nuclear Information System (INIS)

    Three groups of core samples from Marker Bed 139 of the Salado Formation at the Waste Isolation Pilot Plant (WIPP) were analyzed to provide data to support the development of numerical models used to predict the long-term hydrologic and structural response of the WIPP repository. These laboratory experiments, part of the FY93 Experimental Scoping Activities of the Salado Two-Phase Flow Laboratory Program, were designed to (1) generate WIPP-specific porosity and single-phase permeability data, (2) provide information needed to design and implement planned tests to measure two-phase flow properties, including threshold pressure, capillary pressure, and relative permeability, and (3) evaluate the suitability of using analog correlations for the Salado Formation to assess the long-term performance of the WIPP. This report contains a description of the boreholes core samples, the core preparation techniques used, sample sizes, testing procedures, test conditions, and results of porosity and single-phase permeability tests performed at three laboratories: TerraTek, Inc. (Salt Lake City, UT), RE/SPEC, Inc. (Rapid City, SD), and Core Laboratories-Special Core Analysis Laboratory (Carrollton, TX) for Rock Physics Associates. In addition, this report contains the only WIPP-specific two-phase-flow capillary-pressure data for twelve core samples. The WIPP-specific data generated in this laboratory study and in WIPP field-test programs and information from suitable analogs will form the basis for specification of single- and two-phase flow parameters for anhydrite markers beds for WIPP performance assessment calculations

  18. Refractory experience in circulating fluidized bed combustors, Task 7

    Energy Technology Data Exchange (ETDEWEB)

    Vincent, R.Q.

    1989-11-01

    This report describes the results of an investigation into the status of the design and selection of refractory materials for coal-fueled circulating fluidized-bed combustors. The survey concentrated on operating units in the United States manufactured by six different boiler vendors: Babcock and Wilcox, Combustion Engineering, Foster Wheeler, Keeler Dorr-Oliver, Pyropower, and Riley Stoker. Information was obtained from the boiler vendors, refractory suppliers and installers, and the owners/operators of over forty units. This work is in support of DOE's Clean Coal Technology program, which includes circulating fluidized-bed technology as one of the selected concepts being evaluated.

  19. Vacant Nests and Other Factors Influencing Nest Site Selection of Birds of Prey Based on Case Studies in Forest Habitats in the Forest-Steppe and Steppe Zones of Eastern Ukraine

    OpenAIRE

    Stanislav G. Viter

    2015-01-01

    Our study was conducted in 2003–2012 in Eastern Ukraine, in the basin of the Seversky Donets river. The total surveyed area was ca. 900 km2 of nesting habitats suitable for raptors. A total of 69 vacant nests were found, i.e. 33.2 % of the total number of nests (208). Nests occupied by recipient species, i.e. the so-called ‘effective nest pool’, were 23–24, i.e. 33.3–34.7 % of the pool of available nests. Up to 25 % of all pairs of raptors depend on the availability of vacant nests of heteros...

  20. The Shoreline Management Tool - an ArcMap tool for analyzing water depth, inundated area, volume, and selected habitats, with an example for the lower Wood River Valley, Oregon

    Science.gov (United States)

    Snyder, Daniel T.; Haluska, Tana L.; Respini-Irwin, Darius

    2013-01-01

    The Shoreline Management Tool is a geographic information system (GIS) based program developed to assist water- and land-resource managers in assessing the benefits and effects of changes in surface-water stage on water depth, inundated area, and water volume. Additionally, the Shoreline Management Tool can be used to identify aquatic or terrestrial habitat areas where conditions may be suitable for specific plants or animals as defined by user-specified criteria including water depth, land-surface slope, and land-surface aspect. The tool can also be used to delineate areas for use in determining a variety of hydrologic budget components such as surface-water storage, precipitation, runoff, or evapotranspiration. The Shoreline Management Tool consists of two parts, a graphical user interface for use with Esri™ ArcMap™ GIS software to interact with the user to define scenarios and map results, and a spreadsheet in Microsoft® Excel® developed to display tables and graphs of the results. The graphical user interface allows the user to define a scenario consisting of an inundation level (stage), land areas (parcels), and habitats (areas meeting user-specified conditions) based on water depth, slope, and aspect criteria. The tool uses data consisting of land-surface elevation, tables of stage/volume and stage/area, and delineated parcel boundaries to produce maps (data layers) of inundated areas and areas that meet the habitat criteria. The tool can be run in a Single-Time Scenario mode or in a Time-Series Scenario mode, which uses an input file of dates and associated stages. The spreadsheet part of the tool uses a macro to process the results from the graphical user interface to create tables and graphs of inundated water volume, inundated area, dry area, and mean water depth for each land parcel based on the user-specified stage. The macro also creates tables and graphs of the area, perimeter, and number of polygons comprising the user-specified habitat areas

  1. Habitat stability affects dispersal and the ability to track climate change

    DEFF Research Database (Denmark)

    Hof, Christian; Brändle, Martin; Dehling, D. Matthias;

    2012-01-01

    than lotic species. Assuming that climate is an important determinant of species distributions, we hypothesize that lentic species should have distributions that are closer to equilibrium with current climate, and should more rapidly track climatic changes. We tested these hypotheses using datasets......Habitat persistence should influence dispersal ability, selecting for stronger dispersal in habitats of lower temporal stability. As standing (lentic) freshwater habitats are on average less persistent over time than running (lotic) habitats, lentic species should show higher dispersal abilities...... that lentic species track climatic changes more rapidly than lotic species. These results are consistent with the proposed hypothesis that habitat persistence affects the evolution of dispersal....

  2. Physiologic and metagenomic attributes of the rhodoliths forming the largest CaCO3 bed in the South Atlantic Ocean

    OpenAIRE

    Cavalcanti, Giselle S; Gregoracci, Gustavo B.; dos Santos, Eidy O; Silveira, Cynthia B; Meirelles, Pedro M.; Longo, Leila; Gotoh, Kazuyoshi; Nakamura, Shota; Iida, Tetsuya; Sawabe, Tomoo; Rezende, Carlos E; Francini-Filho, Ronaldo B.; Moura, Rodrigo L.; Amado-Filho, Gilberto M.; Thompson, Fabiano L.

    2013-01-01

    Rhodoliths are free-living coralline algae (Rhodophyta, Corallinales) that are ecologically important for the functioning of marine environments. They form extensive beds distributed worldwide, providing a habitat and nursery for benthic organisms and space for fisheries, and are an important source of calcium carbonate. The Abrolhos Bank, off eastern Brazil, harbors the world's largest continuous rhodolith bed (of ∼21 000 km2) and has one of the largest marine CaCO3 deposits (producing 25 me...

  3. Does Wyoming's Core Area Policy Protect Winter Habitats for Greater Sage-Grouse?

    Science.gov (United States)

    Smith, Kurt T; Beck, Jeffrey L; Pratt, Aaron C

    2016-10-01

    Conservation reserves established to protect important habitat for wildlife species are used world-wide as a wildlife conservation measure. Effective reserves must adequately protect year-round habitats to maintain wildlife populations. Wyoming's Sage-Grouse Core Area policy was established to protect breeding habitats for greater sage-grouse (Centrocercus urophasianus). Protecting only one important seasonal habitat could result in loss or degradation of other important habitats and potential declines in local populations. The purpose of our study was to identify the timing of winter habitat use, the extent which individuals breeding in Core Areas used winter habitats, and develop resource selection functions to assess effectiveness of Core Areas in conserving sage-grouse winter habitats in portions of 5 Core Areas in central and north-central Wyoming during winters 2011-2015. We found that use of winter habitats occured over a longer period than current Core Area winter timing stipulations and a substantial amount of winter habitat outside of Core Areas was used by individuals that bred in Core Areas, particularly in smaller Core Areas. Resource selection functions for each study area indicated that sage-grouse were selecting habitats in response to landscapes dominated by big sagebrush and flatter topography similar to other research on sage-grouse winter habitat selection. The substantial portion of sage-grouse locations and predicted probability of selection during winter outside small Core Areas illustrate that winter requirements for sage-grouse are not adequately met by existing Core Areas. Consequently, further considerations for identifying and managing important winter sage-grouse habitats under Wyoming's Core Area Policy are warranted.

  4. Does Wyoming's Core Area Policy Protect Winter Habitats for Greater Sage-Grouse?

    Science.gov (United States)

    Smith, Kurt T.; Beck, Jeffrey L.; Pratt, Aaron C.

    2016-10-01

    Conservation reserves established to protect important habitat for wildlife species are used world-wide as a wildlife conservation measure. Effective reserves must adequately protect year-round habitats to maintain wildlife populations. Wyoming's Sage-Grouse Core Area policy was established to protect breeding habitats for greater sage-grouse ( Centrocercus urophasianus). Protecting only one important seasonal habitat could result in loss or degradation of other important habitats and potential declines in local populations. The purpose of our study was to identify the timing of winter habitat use, the extent which individuals breeding in Core Areas used winter habitats, and develop resource selection functions to assess effectiveness of Core Areas in conserving sage-grouse winter habitats in portions of 5 Core Areas in central and north-central Wyoming during winters 2011-2015. We found that use of winter habitats occured over a longer period than current Core Area winter timing stipulations and a substantial amount of winter habitat outside of Core Areas was used by individuals that bred in Core Areas, particularly in smaller Core Areas. Resource selection functions for each study area indicated that sage-grouse were selecting habitats in response to landscapes dominated by big sagebrush and flatter topography similar to other research on sage-grouse winter habitat selection. The substantial portion of sage-grouse locations and predicted probability of selection during winter outside small Core Areas illustrate that winter requirements for sage-grouse are not adequately met by existing Core Areas. Consequently, further considerations for identifying and managing important winter sage-grouse habitats under Wyoming's Core Area Policy are warranted.

  5. Habitat Evaluation Procedures (HEP) Report; Carey Creek, Technical Report 2005.

    Energy Technology Data Exchange (ETDEWEB)

    Entz, Ray

    2005-05-01

    In August 2002, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the Carey Creek property, an acquisition completed by the Kalispel Tribe of Indians in December 2001. Evaluation species and appropriate models include bald eagle, black-capped chickadee, Canada goose, mallard, yellow warbler, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The Carey Creek Project provides a total of 172.95 Habitat Units (HUs) for the species evaluated. Conifer forest habitat provides 4.91 HUs for bald eagle, black-capped chickadee, and white-tailed deer. Forested wetlands provide 52.68 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. Scrub-shrub wetlands provide 2.82 HUs for mallard, yellow warbler and white-tailed deer. Wet meadow and grassland meadow provide 98.13 HUs for mallard and Canada goose. Emergent wetlands provide 11.53 HUs for mallard, muskrat, and Canada goose. Open water provides 2.88 HUs for Canada goose, mallard, and muskrat. The objective of using HEP at the Carey Creek Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

  6. Describing Willow Flycatcher habitats: scale perspectives and gender differences

    Science.gov (United States)

    Sedgwick, James A.; Knopf, Fritz L.

    1992-01-01

    We compared habitat characteristics of nest sites (female-selected sites) and song perch sites (male-selected sites) with those of sites unused by Willow Flycatchers (Empidonax traillii) at three different scales of vegetation measurement: (1) microplot (central willow [Salix spp.] bush and four adjacent bushes); (2) mesoplot (0.07 ha); and, (3) macroplot (flycatcher territory size). Willow Flycatchers exhibited vegetation preferences at all three scales. Nest sites were distinguished by high willow density and low variability in willow patch size and bush height. Song perch sites were characterized by large central shrubs, low central shrub vigor, and high variability in shrub size. Unused sites were characterized by greater distances between willows and willow patches, less willow coverage, and a smaller riparian zone width than either nest or song perch sites. At all scales, nest sites were situated farther from unused sites in multivariate habitat space than were song perch sites, suggesting (1) a correspondence among scales in their ability to describe Willow Flycatcher habitat, and (2) females are more discriminating in habitat selection than males. Microhabitat differences between male-selected (song perch) and female-selected (nest) sites were evident at the two smaller scales; at the finest scale, the segregation in habitat space between male-selected and female-selected sites was greater than that between male-selected and unused sites. Differences between song perch and nest sites were not apparent at the scale of flycatcher territory size, possibly due to inclusion of (1) both nest and song perch sites, (2) defended, but unused habitat, and/or (3) habitat outside of the territory, in larger scale analyses. The differences between nest and song perch sites at the finer scales reflect their different functions (e.g., nest concealment and microclimatic requirements vs. advertising and territorial defense, respectively), and suggest that the exclusive use

  7. Integration Process for the Habitat Demonstration Unit

    Science.gov (United States)

    Gill, Tracy; Merbitz, Jerad; Kennedy, Kriss; Tn, Terry; Toups, Larry; Howe, A. Scott; Smitherman, David

    2011-01-01

    The Habitat Demonstration Unit (HDU) is an experimental exploration habitat technology and architecture test platform designed for analog demonstration activities. The HDU previously served as a test bed for testing technologies and sub-systems in a terrestrial surface environment. in 2010 in the Pressurized Excursion Module (PEM) configuration. Due to the amount of work involved to make the HDU project successful, the HDU project has required a team to integrate a variety of contributions from NASA centers and outside collaborators The size of the team and number of systems involved With the HDU makes Integration a complicated process. However, because the HDU shell manufacturing is complete, the team has a head start on FY--11 integration activities and can focus on integrating upgrades to existing systems as well as integrating new additions. To complete the development of the FY-11 HDU from conception to rollout for operations in July 2011, a cohesive integration strategy has been developed to integrate the various systems of HDU and the payloads. The highlighted HDU work for FY-11 will focus on performing upgrades to the PEM configuration, adding the X-Hab as a second level, adding a new porch providing the astronauts a larger work area outside the HDU for EVA preparations, and adding a Hygiene module. Together these upgrades result in a prototype configuration of the Deep Space Habitat (DSH), an element under evaluation by NASA's Human Exploration Framework Team (HEFT) Scheduled activates include early fit-checks and the utilization of a Habitat avionics test bed prior to installation into HDU. A coordinated effort to utilize modeling and simulation systems has aided in design and integration concept development. Modeling tools have been effective in hardware systems layout, cable routing, sub-system interface length estimation and human factors analysis. Decision processes on integration and use of all new subsystems will be defined early in the project to

  8. Channel morphodynamics and habitat recovery in a river reach affected by gravel-mining (River Ésera, Ebro basin)

    Science.gov (United States)

    Lopez-Tarazon, J. A.; Lobera, G.; Andrés-Doménech, I.; Martínez-Capel, F.; Muñoz-Mas, R.; Vallés, F.; Tena, A.; Vericat, D.; Batalla, R. J.

    2012-04-01

    Physical processes in rivers are the result of the interaction between flow regime and hydraulics, morphology, sedimentology and sediment transport. The frequency and magnitude of physical disturbance (i.e. bed stability) control habitat integrity and, consequently, ecological diversity of a particular fluvial system. Most rivers experience human-induced perturbations that alter such hydrosedimentary equilibrium, thus affecting the habitat of aquatic species. A dynamic balance may take long time to be newly attained. Within this context, gravel mining is well known to affect channel characteristics mostly at the local scale, but its effect may also propagate downstream and upstream. Sedimentary forms are modified during extraction and habitat features are reduced or even eliminated. Effects tend to be most acute in contrasted climatic environments, such as the Mediterranean areas, in which climatic and hydrological variability maximises effects of impacts and precludes short regeneration periods. Present research focuses on the evolution of a river reach, which has experienced an intense gravel extraction. The selected area is located in the River Ésera (Ebro basin), where interactions between morphodynamics and habitat recovery are examined. Emphasis is put on monitoring sedimentary, morphological and hydraulic variables to later compare pre (t0) and post (t1, t2... tn) extraction situations. Methodology for all time monitoring steps (i.e. ti) includes: i) characterization of grain size distribution at all of the different hydromorphological units within the reach; ii) description of channel morphology (together with changes before and after floods) by means of close-range aerial photographs, which are taken with a digital camera attached to a 1m3 helium balloon (i.e. BLIMP); and iii) determination of flow parameters from 2D hydraulic modelling that is based on detailed topographical data obtained from Leica® GNSS/GPS and robotic total station, and River

  9. Mangrove habitat use by juvenile reef fish: meta-analysis reveals that tidal regime matters more than biogeographic region.

    Directory of Open Access Journals (Sweden)

    Mathias M Igulu

    Full Text Available Identification of critical life-stage habitats is key to successful conservation efforts. Juveniles of some species show great flexibility in habitat use while other species rely heavily on a restricted number of juvenile habitats for protection and food. Considering the rapid degradation of coastal marine habitats worldwide, it is important to evaluate which species are more susceptible to loss of juvenile nursery habitats and how this differs across large biogeographic regions. Here we used a meta-analysis approach to investigate habitat use by juvenile reef fish species in tropical coastal ecosystems across the globe. Densities of juvenile fish species were compared among mangrove, seagrass and coral reef habitats. In the Caribbean, the majority of species showed significantly higher juvenile densities in mangroves as compared to seagrass beds and coral reefs, while for the Indo-Pacific region seagrass beds harbored the highest overall densities. Further analysis indicated that differences in tidal amplitude, irrespective of biogeographic region, appeared to be the major driver for this phenomenon. In addition, juvenile reef fish use of mangroves increased with increasing water salinity. In the Caribbean, species of specific families (e.g. Lutjanidae, Haemulidae showed a higher reliance on mangroves or seagrass beds as juvenile habitats than other species, whereas in the Indo-Pacific family-specific trends of juvenile habitat utilization were less apparent. The findings of this study highlight the importance of incorporating region-specific tidal inundation regimes into marine spatial conservation planning and ecosystem based management. Furthermore, the significant role of water salinity and tidal access as drivers of mangrove fish habitat use implies that changes in seawater level and rainfall due to climate change may have important effects on how juvenile reef fish use nearshore seascapes in the future.

  10. Interfacing models of wildlife habitat and human development to predict the future distribution of puma habitat

    Science.gov (United States)

    Burdett, Christopher L.; Crooks, Kevin R.; Theobald, David M.; Wilson, Kenneth R.; Boydston, Erin E.; Lyren, Lisa A.; Fisher, Robert N.; Vickers, T. Winston; Morrison, Scott A.; Boyce, Walter M.

    2010-01-01

    The impact of human land uses on ecological systems typically differ relative to how extensively natural conditions are modified. Exurban development is intermediate-intensity residential development that often occurs in natural landscapes. Most species-habitat models do not evaluate the effects of such intermediate levels of human development and even fewer predict how future development patterns might affect the amount and configuration of habitat. We addressed these deficiencies by interfacing a habitat model with a spatially-explicit housing-density model to study the effect of human land uses on the habitat of pumas (Puma concolor) in southern California. We studied the response of pumas to natural and anthropogenic features within their home ranges and how mortality risk varied across a gradient of human development. We also used our housing-density model to estimate past and future housing densities and model the distribution of puma habitat in 1970, 2000, and 2030. The natural landscape for pumas in our study area consisted of riparian areas, oak woodlands, and open, conifer forests embedded in a chaparral matrix. Pumas rarely incorporated suburban or urban development into their home ranges, which is consistent with the hypothesis that the behavioral decisions of individuals can be collectively manifested as population-limiting factors at broader spatial scales. Pumas incorporated rural and exurban development into their home ranges, apparently perceiving these areas as modified, rather than non-habitat. Overall, pumas used exurban areas less than expected and showed a neutral response to rural areas. However, individual pumas that selected for or showed a neutral response to exurban areas had a higher risk of mortality than pumas that selected against exurban habitat. Exurban areas are likely hotspots for puma-human conflict in southern California. Approximately 10% of our study area will transform from exurban, rural, or undeveloped areas to suburban or

  11. Torsion testing of bed joints

    DEFF Research Database (Denmark)

    Hansen, Klavs Feilberg; Pedersen, Carsten Mørk

    2008-01-01

    This paper describes a simple test method for determining the torsion strength of a single bed joint between two bricks and presents results from testing using this test method. The setup for the torsion test is well defined, require minimal preparation of the test specimen and the test can...... be carried out directly in a normal testing machine. The torsion strength is believed to be the most important parameter in out-of-plane resistance of masonry walls subjected to bending about an axis perpendicular to the bed joints. The paper also contains a few test results from bending of small walls about...... an axis perpendicular to the bed joints, which indicate the close connection between these results and results from torsion tests. These characteristics make the torsion strength well suited to act as substitute parameter for the bending strength of masonry about an axis perpendicular to the bed joints....

  12. Sea bed mapping and inspection

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    The conference has 24 presentations on the topics: Sea bed mapping, inspection, positioning, hydrography, marine archaeology, remote operation vehicles and computerized simulation technologies, oil field activities and plans, technological experiences and problems. (tk)

  13. Bed Bugs: The Australian Response

    Directory of Open Access Journals (Sweden)

    Richard C. Russell

    2011-04-01

    Full Text Available Australia has experienced a sudden and unexpected resurgence in bed bug infestations from both Cimex lectularius L. and Cimex hemipterus F. A survey in 2006 revealed that infestations had increased across the nation by an average of 4,500% since the start of the decade. In response, a multi-disciplinary approach to combat the rise of this public health pest was implemented and involved the coordinated efforts of several organizations. The key components of the strategy included the introduction of a pest management standard ‘A Code of Practice for the Control of Bed Bug Infestations in Australia’ that defines and promotes ‘best practice’ in bed bug eradication, the development of a policy and procedural guide for accommodation providers, education of stakeholders in best management practices, and research. These strategies continue to evolve with developments that lead to improvements in ‘best practice’ while bed bugs remain problematic in Australia.

  14. Better backs by better beds?

    DEFF Research Database (Denmark)

    Bergholdt, Kim; Fabricius, Rasmus N; Bendix, Tom

    2008-01-01

    using the probably most relevant "worst case" data. There were no relevant difference between the effects of the water bed and the foam bed. CONCLUSION: The Waterbed and foam mattress' did influence back symptoms, function and sleep more positively as apposed to the hard mattress, but the differences...... mattresses have a positive effect on LBP, and especially a hard mattress is commonly believed to have a positive effect. METHODS: One hundred sixty CLBP patients were randomized to 1 of 3 groups, having a mattress/bed mounted in their sleeping room for 1 month. The beds were: (1) waterbed (Akva), (2) body......-conforming foam mattress (Tempur), and (3) a hard mattress (Innovation Futon). At baseline and after 4 weeks, a blinded observer interviewed the patients on LBP levels (0-10), daily function (activities of daily living, 0-30), and on the amount of sleeping hours/night. RESULTS: Because of dropout of 19 patients...

  15. Bed-exit alarm effectiveness

    Science.gov (United States)

    Capezuti, Elizabeth; Brush, Barbara L.; Lane, Stephen; Rabinowitz, Hannah U.; Secic, Michelle

    2009-01-01

    This study describes the accuracy of two types of bed-exit alarms to detect bed-exiting body movements: pressure-sensitive and a pressure sensitive combined with infrared beam detectors (dual sensor system). We also evaluated the occurrence of nuisance alarms, or alarms that are activated when a participant does not attempt to get out of bed. Fourteen nursing home residents were directly observed for a total of 256 nights or 1,636.5 hours; an average of 18.3 ± 22.3 (± S.D.) nights/participant for an average of 6.4 ± 1.2 hours/night. After adjusting for body movements via repeated measures, Poisson regression modeling, the least squares adjusted means show a marginally significant difference between the type of alarm groups on the number of true positives (mean/S.E.M. = 0.086/1.617) for pressure-sensitive vs. dual sensor alarm (0.593/1.238; p = 0.0599) indicating that the dual sensor alarm may have a higher number of true positives. While the dual sensor bed-exit alarm was more accurate than the pressure sensitive alarm in identifying bed-exiting body movements and reducing the incidence of false alarms, false alarms were not eliminated altogether. Alarms are not a substitute for staff; adequate staff availability is still necessary when residents need or wish to exit bed. PMID:18508138

  16. Northern European Satellite Test Bed

    Science.gov (United States)

    Schuster-Bruce, Alan; Lawson, James; Quinlan, Michael; McGregor, Andrew

    Satellite Based Augmentation Systems are being developed in Europe (EGNOS), the USA (WAAS), and in Japan (MSAS). As part of their support to EGNOS, NATS and Racal have developed and deployed a prototype SBAS system called the Northern European Satellite Test Bed (NEST Bed). NEST Bed uses GPS L1/L2 reference stations at: Aberdeen, Rotterdam, Ankara, Cadiz, Keflavik, and Bronnoysund. Data is sent to the Master Control Centre at NATS Gatwick Services Management Centre for processing. The resulting 250 bits-per-second message is sent to Goonhilly for up-linking by BT to the Navigation Payload of either the Inmarsat AOR-E or F5 spare satellite. NEST Bed was deployed and commissioned during summer 1998, and flight tests were successfully demonstrated at the September 1998 Farnborough Air Show where approaches were flown to Boscombe Down on the DERA BAC1-11 aircraft. In October 1998, a NATS/FAA flight trial was held in Iceland involving NEST Bed and the FAA NSTB. NEST Bed is also being used for SARPS validation.

  17. Landscape structure shapes habitat finding ability in a butterfly.

    Directory of Open Access Journals (Sweden)

    Erik Öckinger

    Full Text Available Land-use intensification and habitat fragmentation is predicted to impact on the search strategies animals use to find habitat. We compared the habitat finding ability between populations of the speckled wood butterfly (Pararge aegeria L. from landscapes that differ in degree of habitat fragmentation. Naïve butterflies reared under standardized laboratory conditions but originating from either fragmented agricultural landscapes or more continuous forested landscapes were released in the field, at fixed distances from a target habitat patch, and their flight paths were recorded. Butterflies originating from fragmented agricultural landscapes were better able to find a woodlot habitat from a distance compared to conspecifics from continuous forested landscapes. To manipulate the access to olfactory information, a subset of individuals from both landscape types were included in an antennae removal experiment. This confirmed the longer perceptual range for butterflies from agricultural landscapes and indicated the significance of both visual and olfactory information for orientation towards habitat. Our results are consistent with selection for increased perceptual range in fragmented landscapes to reduce dispersal costs. An increased perceptual range will alter the functional connectivity and thereby the chances for population persistence for the same level of structural connectivity in a fragmented landscape.

  18. Clay Animals and Their Habitats

    Science.gov (United States)

    Adamson, Kay

    2010-01-01

    Creating clay animals and their habitats with second-grade students has long been one of the author's favorite classroom activities. Students love working with clay and they also enjoy drawing animal homes. In this article, the author describes how the students created a diorama instead of drawing their clay animal's habitat. This gave students…

  19. Habitat specialization through germination cueing

    DEFF Research Database (Denmark)

    Ten Brink, Dirk-Jan; Hendriksma, Harmen; Bruun, Hans Henrik

    2013-01-01

    This study examined the adaptive association between seed germination ecology and specialization to either forest or open habitats across a range of evolutionary lineages of seed plants, in order to test the hypotheses that (1) species' specialization to open vs. shaded habitats is consistently...

  20. A comparison between different methods for determining grain distribution in coarse channel beds

    Institute of Scientific and Technical Information of China (English)

    Alessio Cislaghi; Enrico Antonio Chiaradia; Gian Battista Bischetti

    2016-01-01

    The determination of grain size distribution in alluvial channels plays a crucial role in understanding fluvial dynamics and processes (e.g., hydraulic resistance, sediment transport and erosion, and habitat suitability). However, to determine an accurate distribution, tremendous field efforts are often required. Traditionally, the grain size distribution of channel beds have been obtained by manually counting a set of randomly selected stones (the“pebble count”). Based on this elementary principle, many authors have proposed different adaptations to overcome weaknesses and problems with the original method; with the development of digital technology, photographic methods have been developed in order to sig-nificantly reduce the time spent in the field. Two of these“image-assisted”methods include Automated Grain Sizing, AGS, and Manual Photo Sieving, MPS. In this study, AGS and MPS were applied under ideal laboratory conditions, to be used as reference, and in two field conditions with different degrees of difficulty in terms of visual determination of the grain size distribution; these included an artificial unlined channel and two natural mountainous streams. The results were compared with those obtained with the pebble-count method. In general, strong agreement between the methods was found when they were applied under favorable conditions (”the laboratory”), and the differences between the image-assisted and pebble count methods were similar to those found in previous studies. Despite being more time consuming, MPS was deemed preferable to AGS when conditions are not optimal;in these cases, the time spent on image elaboration significantly increased in the AGS method (approximately three-fold), but the estimation error of the median grain size decreased by approximately 37%. The use of image-assisted analysis has proven to be robust for characterizing sediment in watercourse beds and reducing fieldwork time, but because field conditions can

  1. Habitat features and predictive habitat modeling for the Colorado chipmunk in southern New Mexico

    Science.gov (United States)

    Rivieccio, M.; Thompson, B.C.; Gould, W.R.; Boykin, K.G.

    2003-01-01

    Two subspecies of Colorado chipmunk (state threatened and federal species of concern) occur in southern New Mexico: Tamias quadrivittatus australis in the Organ Mountains and T. q. oscuraensis in the Oscura Mountains. We developed a GIS model of potentially suitable habitat based on vegetation and elevation features, evaluated site classifications of the GIS model, and determined vegetation and terrain features associated with chipmunk occurrence. We compared GIS model classifications with actual vegetation and elevation features measured at 37 sites. At 60 sites we measured 18 habitat variables regarding slope, aspect, tree species, shrub species, and ground cover. We used logistic regression to analyze habitat variables associated with chipmunk presence/absence. All (100%) 37 sample sites (28 predicted suitable, 9 predicted unsuitable) were classified correctly by the GIS model regarding elevation and vegetation. For 28 sites predicted suitable by the GIS model, 18 sites (64%) appeared visually suitable based on habitat variables selected from logistic regression analyses, of which 10 sites (36%) were specifically predicted as suitable habitat via logistic regression. We detected chipmunks at 70% of sites deemed suitable via the logistic regression models. Shrub cover, tree density, plant proximity, presence of logs, and presence of rock outcrop were retained in the logistic model for the Oscura Mountains; litter, shrub cover, and grass cover were retained in the logistic model for the Organ Mountains. Evaluation of predictive models illustrates the need for multi-stage analyses to best judge performance. Microhabitat analyses indicate prospective needs for different management strategies between the subspecies. Sensitivities of each population of the Colorado chipmunk to natural and prescribed fire suggest that partial burnings of areas inhabited by Colorado chipmunks in southern New Mexico may be beneficial. These partial burnings may later help avoid a fire

  2. Habitat selection and natural enemy function of Chrysopa pallens rambur in agroforestry systems%农林复合环境大草蛉生境选择取向及天敌效能

    Institute of Scientific and Technical Information of China (English)

    杨钊; 赵广亮; 闫国增; 周在豹; 田作宝; 魏婉红; 张东; 李凯

    2015-01-01

    大草蛉( Chrysopa pallens Rambur)是华北农区优势天敌昆虫之一。华北农区农林复合系统中作物农田、林带所组成的农林生境,就其中的大草蛉对栖息环境、产卵地点、越冬场所等不同生境的选择取向及天敌追随效能展开了多角度研究,结果表明:(1)大草蛉成虫对作物蚜虫具有明显的追随效应,其幼虫对作物蚜虫的空间跟随作用显著,且在不同空间层次均有控制作物蚜虫的表现(空间重叠度指数:P幼空间>0.65);大草蛉的采食虫态期与蚜虫的发生期同步(时间重叠度指数:P卵时间0.05,α=0.05);(4)大草蛉在栖息生境中具有季节移动性和偏好选择性双重特点:夏秋两季作物生长期内大草蛉从林带迁飞往农田,偏好在大豆、花生田中栖息( LSD法:P=0.005 0.65) . The predatory stage of C. pallens was synchronized with aphid emergences (temporal niche overlap index: PEgg·Temporal< 0.65). Second, forest belts adjacent to agronomic fields were the main overwintering places for C. pallens after the autumn harvest ( Pα= 0.001,α = 0.05) , which was important for maintaining the C. pallens population. Third, by cocooning as prepupae to overwinter in forest belts, the larvae of C. pallens primarily used bark cracks, topsoil, and fallen leaves and branches as overwintering places. There was no noticeable preference among these three types of overwintering habitats (Pα= 0.466, α = 0.05). Fourth, C. pallens migrated seasonally due to changes in habitat preference. During crop growth in summer and autumn, C. pallens migrated from forest belts to agronomic fields, preferring soybean and peanut habitats, where high-densities of aphids first appeared (LSD: Pα= 0.005, α = 0.01). After the fall harvest, and during winter and spring, C. pallens generally occupied forest belts, which were the only places left to overwinter after the crops were harvested. C. pallens preferred poplar coppice shoots, possibly

  3. 49 CFR 236.336 - Locking bed.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Locking bed. 236.336 Section 236.336 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Instructions § 236.336 Locking bed. The various parts of the locking bed, locking bed supports, and tappet...

  4. Diet, abundance and distribution as indices of turbot ( Psetta maxima L.) release habitat suitability

    DEFF Research Database (Denmark)

    Sparrevohn, Claus Reedtz; Støttrup, Josianne

    2008-01-01

    Selection of a suitable release habitat is critical for stock enhancement. As part of the Danish turbot stock enhancement program, individually tagged, artificially reared juveniles were released into three different habitats. Data from the recaptures in the following year revealed a significant...... effect of release habitat on turbot growth. This raised the question whether such differences in growth could have been predicted before the release by comparing easily measurable characteristics of wild turbot caught in the different habitats. Three characteristics of wild turbot were examined: the diet......, natural abundance, and depth distribution within the habitats. A marked difference was found among habitats in the timing of the diet change from the suboptimal exoskeleton carrying prey items such as crustaceans to fish. The habitat where the wild turbot had the lowest occurrence of fish in their diet...

  5. Structural habitat predicts functional dispersal habitat of a large carnivore: how leopards change spots.

    Science.gov (United States)

    Fattebert, Julien; Robinson, Hugh S; Balme, Guy; Slotow, Rob; Hunter, Luke

    2015-10-01

    Natal dispersal promotes inter-population linkage, and is key to spatial distribution of populations. Degradation of suitable landscape structures beyond the specific threshold of an individual's ability to disperse can therefore lead to disruption of functional landscape connectivity and impact metapopulation function. Because it ignores behavioral responses of individuals, structural connectivity is easier to assess than functional connectivity and is often used as a surrogate for landscape connectivity modeling. However using structural resource selection models as surrogate for modeling functional connectivity through dispersal could be erroneous. We tested how well a second-order resource selection function (RSF) models (structural connectivity), based on GPS telemetry data from resident adult leopard (Panthera pardus L.), could predict subadult habitat use during dispersal (functional connectivity). We created eight non-exclusive subsets of the subadult data based on differing definitions of dispersal to assess the predictive ability of our adult-based RSF model extrapolated over a broader landscape. Dispersing leopards used habitats in accordance with adult selection patterns, regardless of the definition of dispersal considered. We demonstrate that, for a wide-ranging apex carnivore, functional connectivity through natal dispersal corresponds to structural connectivity as modeled by a second-order RSF. Mapping of the adult-based habitat classes provides direct visualization of the potential linkages between populations, without the need to model paths between a priori starting and destination points. The use of such landscape scale RSFs may provide insight into predicting suitable dispersal habitat peninsulas in human-dominated landscapes where mitigation of human-wildlife conflict should be focused. We recommend the use of second-order RSFs for landscape conservation planning and propose a similar approach to the conservation of other wide-ranging large

  6. The importance of ambient sound level to characterise anuran habitat.

    Directory of Open Access Journals (Sweden)

    Sandra Goutte

    Full Text Available Habitat characterisation is a pivotal step of any animal ecology study. The choice of variables used to describe habitats is crucial and need to be relevant to the ecology and behaviour of the species, in order to reflect biologically meaningful distribution patterns. In many species, acoustic communication is critical to individuals' interactions, and it is expected that ambient acoustic conditions impact their local distribution. Yet, classic animal ecology rarely integrates an acoustic dimension in habitat descriptions. Here we show that ambient sound pressure level (SPL is a strong predictor of calling site selection in acoustically active frog species. In comparison to six other habitat-related variables (i.e. air and water temperature, depth, width and slope of the stream, substrate, SPL had the most important explanatory power in microhabitat selection for the 34 sampled species. Ambient noise was particularly useful in differentiating two stream-associated guilds: torrents and calmer streams dwelling species. Guild definitions were strongly supported by SPL, whereas slope, which is commonly used in stream-associated habitat, had a weak explanatory power. Moreover, slope measures are non-standardized across studies and are difficult to assess at small scale. We argue that including an acoustic descriptor will improve habitat-species analyses for many acoustically active taxa. SPL integrates habitat topology and temporal information (such as weather and hour of the day, for example and is a simple and precise measure. We suggest that habitat description in animal ecology should include an acoustic measure such as noise level because it may explain previously misunderstood distribution patterns.

  7. Monitoring the use of artificial log pile otter holts using hair analysis from bedding

    Directory of Open Access Journals (Sweden)

    Cowell D.

    2001-04-01

    Full Text Available Nineteen, approximately ten year old log pile holts (LPH in mid-Wales, UK, were dismantled prior to reconstruction and any bedding from couches removed for analysis. The plant material making up the bedding was identified and animal guard hairs contained within it were determined to species. The bedding material simply consisted of opportunistically available material with little evident selection. Hairs of cow and sheep were clearly brought in with the bedding but it is suggested that hairs of otter, badger, fox, dog, cat, American mink and polecat indicate use of the LPH by the species concerned. A possible pine marten record is also considered.

  8. PARTICLE COATING BY CHEMICAL VAPOR DEPOSITION IN A FLUIDI7ED BED REACTOR

    Institute of Scientific and Technical Information of China (English)

    Gregor; Czok; Joachim; Werther

    2005-01-01

    Aluminum coatings were created onto glass beads by chemical vapor deposition in a fluidized bed reactor at different temperatures. Nitrogen was enriched with Triisobutylaluminum (TIBA) vapor and the latter was thermally decomposed inside the fluidized bed to deposit the elemental aluminum. To ensure homogeneous coating on the bed material, the fluidizing conditions necessary to avoid agglomeration were investigated for a broad range of temperatures.The deposition reaction was modeled on the basis of a discrete particle simulation to gain insight into homogeneity and thickness of the coating throughout the bed material. In particular, the take-up of aluminum was traced for selected particles that exhibited a large mass of deposited aluminum.

  9. Collembola Diversity of Moss Habitats in the Sopron Region, NW-Hungary

    Directory of Open Access Journals (Sweden)

    TRASER, György

    2006-01-01

    Full Text Available The Collembola fauna of the moss flora in the Sopron region was studied. 18 moss species aswell as 3.451 Collembola specimens (belonging to 60 species were collected in 2003/04 in moss samplesof three habitats. The highest Collembola diversity was found in Tómalom (a reed bed habitat where verylow abundance and relatively high species richness were characteristic. The Collembola diversity of theother two habitats (Sopron, Botanic Garden; Fertőrákos – a dry xerophile grass habitat was lower. Theresults have shown a relatively high similarity between the Collembola communities in Sopron andFertőrákos while just the opposite was observed between the Sopron and Tómalom samples.

  10. Impact-induced microbial endolithic habitats

    Science.gov (United States)

    Cockell, C. S.; Lee, P.; Osinski, G.; Horneck, G.; Broady, P.

    2002-10-01

    Asteroid and comet impacts on Earth are commonly viewed as agents of ecosystem destruction, be it on local or global scales. However, for some microbial communities, impacts may represent an opportunity for habitat formation as some substrates are rendered more suitable for colonization when processed by impacts. We describe how heavily shocked gneissic crystalline basement rocks exposed at the Haughton impact structure, Devon Island, Nunavut, Arctic Canada, are hosts to endolithic photosynthetic microorganisms in significantly greater abundance than lesser-shocked or unshocked gneisses. Two factors contribute to this enhancement: (a) increased porosity due to impact fracturing and differential mineral vaporization, and (b) increased translucence due to the selective vaporization of opaque mineral phases. Using biological ultraviolet radiation dosimetry, and by measuring the concentrations of photoprotective compounds, we demonstrate that a covering of 0.8 mm of shocked gneiss can provide substantial protection from ultraviolet radiation, reducing the inactivation of Bacillus subtilis spores by 2 orders of magnitude. The colonisation of the shocked habitat represents a potential mechanism for pioneer microorganisms to invade an impact structure in the earliest stages of post-impact primary succession. The communities are analogous to the endolithic communities associated with sedimentary rocks in Antarctica, but because they occur in shocked crystalline rocks, they illustrate a mechanism for the creation of microbial habitats on planetary surfaces that do not have exposed sedimentary units. This might have been the case on early Earth. The data have implications for the microhabitats in which biological signatures might be sought on Mars.

  11. Particle motion in fluidised beds

    International Nuclear Information System (INIS)

    Gas fluidised beds are important components in many process industries, e.g. coal combustors and granulators, but not much is known about the movement of the solids. Positron Emission Particle Tracking (PEPT) enables the movement of a single, radioactive tracer particle to be followed rapidly and faithfully. Experiments were carried out in columns sized between 70 and 240mm. diameter, operating in the bubbling regime at ambient process conditions using particles of group B and D (Geldart Classification). Particle motion was tracked and the data applied to models for particle movement at the gas distributor as well as close to other surfaces and to models for particle circulation in beds of cohesive particles. In the light of these data, models for particle and bubble interaction, particle circulation, segregation, attrition, erosion, heat transfer and fluidised bed scale-up rules were reassessed. Particle motion is directly caused by bubble motion, and their velocities were found to be equal for particles travelling in a bubble. PEPT enables particle circulation to be measured, giving a more accurate correlation for future predictions. Particle motion follows the scale-up rules based on similarities of the bubble motion in the bed. A new group of parameters was identified controlling the amount of attrition in fluidised beds and a new model to predict attrition is proposed. (author)

  12. Development of preliminary trigger values for selected pollutants for the protection of soils as a habitat for soil organisms; Entwicklungen von Pruefwertempfehlungen fuer ausgewaehlte Schadstoffe zum Schutz des Bodens als Lebensraum fuer Bodenorganismen

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, B.M. [Technische Univ. Berlin (Germany). Inst. fuer Oekologie; Hund-Rinke, K. [FhG-IUCT Schmallenberg (Germany); Pieper, S. [Freie Univ. Berlin (Germany). Inst. fuer Biologie; Roembke, J. [ECT Oekotoxikologie GmbH, Floersheim (Germany); Marschner, A. [Umweltbundesamt, Berlin (Germany)

    2004-07-01

    Goal and Scope. In the German Federal Soil Protection and Contaminated Sites Ordinance there are no ecotoxicological trigger values for the protection of soil as a habitat for soil organisms. The objective of this study was to derive preliminary trigger values for the habitat function of soils. This was done by collecting data on the impact of priority pollutants on soil organisms and plants followed by the parallel use of the Factorial Application Method (FAME) and Distribution Based Extrapolation (DIBAEX) and a final verification of the plausibility of the calculated trigger values by means of an ecotoxicological test battery. Methods. Data on the effects of pollutants on soil organisms and plants were recorded in a specific database (Soil Value). Subsequently, we derived so-called ''working trigger values'' using the extrapolation methods FAME (factorial application method) and DIBAEX (distribution based extrapolation). In the second phase of the project, we verified experimentally the plausibility of these values by means of an ecotoxicological test battery. Test substrate was a sandy soil with low sorption capacity and organic carbon content which was mixed with fresh pollutants (e.g. heavy metal salts) and polluted soil material from contaminated sites (aged contamination), respectively. Organisms tested were microorganisms, plants, earthworms, springtails and nematodes. Results and Conclusions. We calculated working trigger values for 12 pollutants based on 900 datasets compiled in the data base. The lavoratory investigations showed the freshly added contaminants to be less strongly adsorbed to the soil than those added by the use of contaminated soil material. Nevertheless, aged contaminations displayed often the same inhibitive effects as the freshly added chemicals. The results achieved in the second phase of the project were also recorded in the Soil-Value database. Based on the new data set, final trigger values were derived for the

  13. Steelhead Critical Habitat, Coast - NOAA [ds122

    Data.gov (United States)

    California Department of Resources — This layer depicts areas designated for Steelhead Critical Habitat as well as habitat type and quality in the Coastal California Steelhead ESUs (evolutionarily...

  14. Guam and the Northern Mariana Islands ESI: HABITATS (Habitat Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for benthic marine habitats and plants in Guam and the Northern Mariana Islands. Vector polygons in this...

  15. Southeast Alaska ESI: HABITATS (Habitat and Plant Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for seagrass habitats in Southeast Alaska. Vector polygons in this data set represent locations of seagrass...

  16. Riparian Habitat - Product of 2 riparian habitat workshops

    Data.gov (United States)

    California Department of Resources — In two riparian habitat workshops held between 2001 and 2002, scientists and managers identified the need for determining the scope of a consistent and acceptable...

  17. Habitat requirements of juvenile salmonids:towards ecologically-based fisheries management in boreal streams

    OpenAIRE

    Mäki-Petäys, A. (Aki)

    1999-01-01

    Abstract For effective management of stream salmonids, it is essential to (i) assess the productive potential of a stream in relation to species-specific habitat requirements, and to (ii) identify the key factors underlying any bottleneck periods during the life cycle of a fish. For this purpose, this PhD-thesis focuses on the mechanisms of habitat selection by juvenile salmonids in boreal streams. Habitat preference curves for depth, water velocity, substrate and instream cover for br...

  18. Seedling stage strategies as a means of habitat specialization in herbaceous plants.

    Directory of Open Access Journals (Sweden)

    Dirk-Jan ten Brink

    Full Text Available The regeneration niche has been little investigated in studies of community assembly and plant distribution. We examined adaptive associations between seedling traits and habitat specialization. Two habitat contrasts were investigated across several evolutionary lineages of angiosperms: species specialized to forest vs. open habitats and to dry vs. wet habitats. We also tested whether effects of shade and drought vary independently or, alternatively, if shade may amplify effects on drought-stressed plants. Seedling response in terms of growth rate, height, slenderness, specific leaf area (SLA and degree of elongation (longest internode; petiole or leaf-sheath depending on species' morphology to light and watering treatments was assessed. We used a factorial design involving three light regimes and two watering frequencies. The open-shaded habitat contrast and the dry-wet habitat contrast were investigated using six and five pairs of congeneric species, respectively. The congeneric species pair design controlled for confounding effects of evolutionary history prior to divergence in habitat specialization. Seedling growth rate generally decreased with shade and reduced watering frequency. Plant height was generally largest at intermediate light. Specialization to shaded habitats was associated with a more conservative growth strategy, i.e. showing a more modest growth response to increasing light. Species from all habitats showed the highest relative elongation at intermediate light, except for the moist-habitat species, for which elongation increased with shade. Contrary to our expectations, species from dry habitats grew bigger than species from moist habitats in all treatments. SLA responded to the light treatment, but not to watering regime. The contrasting light and moisture conditions across habitats appear to not have selected for differences in SLA. We conclude that seedling phase strategies of resource allocation in temperate herbs

  19. Nail bed expansion: A new technique for correction of multiple isolated congenital micronychia

    Directory of Open Access Journals (Sweden)

    Gholamhossein Ghaffarpour

    2014-01-01

    Full Text Available Congenital micronychia may involve big toes or may involve other nails. The etiology of micronychia is not clear but amniotic bands, teratogens (drugs, alcohol, Nail Patella Syndrome etc. A 44-year-old woman with multiple isolated congenital micronychia over her hands and feet was selected. The major affected nails were thumbs and Index fingers. Surgical method were done step by step: Anesthesia of the area, extraction of short nail, elevation of nail bed, longitudinal nail bed incisions, suturing the lateral nail bed to the nail wall, covering the nail bed by a splint of plastic suction tube, bandage with gauze Vaseline. Finally, we hypnotized that in congenital micronychia, the main pathology is in nail bed; through this theory by nail bed expansion better outcomes are coming.

  20. Designing a CR Test bed

    DEFF Research Database (Denmark)

    Cattoni, Andrea Fabio; Buthler, Jakob Lindbjerg; Tonelli, Oscar;

    2014-01-01

    Research on intelligent and reconfigurable wireless systems is in continuous evolution. Nevertheless, in order to fix some keystones, more and more researchers are entering the idea of research-oriented test beds. Unfortunately, it is very difficult for a wide number of research groups to start...... with their own set up, since the potential costs and efforts could not pay back in term of expected research results. Software Defined Radio solutions offer an easy way to communication researchers for the development of customized research test beds. While several hardware products are commercially available...... they are up and running in generating results. With this chapter we would like to provide a tutorial guide, based on direct experience, on how to enter in the world of test bed-based research, providing both insight on the issues encountered in every day development, and practical solutions. Finally...

  1. Seasonal habitat preference by the flagship species Testudo hermanni: Implications for the conservation of coastal dunes.

    Science.gov (United States)

    Berardo, Fabiana; Carranza, Maria Laura; Frate, Ludovico; Stanisci, Angela; Loy, Anna

    2015-05-01

    In this study, we explored if, how, and when the European Union habitats (EU sensu Habitats Directive 92/43/CEE) are used by the flagship species Testudo hermanni in a well-preserved coastal dune system of the Italian peninsula. Radio telemetry data and fine-scale vegetation habitat mapping were used to address the following questions: (a) is each EU habitat used differentially by Hermann's tortoises? (b) is there any seasonal variation in this utilization pattern? (c) how does each habitat contribute to the ecological requirements of the tortoises? Nine tortoises were fitted with transmitters and monitored for the entire season of activity. The eight EU habitats present in the study area were surveyed and mapped using GIS. The seasonal preferential use or avoidance of each habitat was tested by comparing, through bootstrap tests, the proportion of habitat occupied (piTh) with the proportion of available habitat in the entire landscape (piL). The analysis of 340 spatial locations showed a marked preference for the Cisto-Lavanduletalia dune sclerophyllous scrubs (EU code 2260) and a seasonal selection of Juniperus macrocarpa bushes (EU code 2250(*)), wooded dunes with Pinus (EU code 2270) and mosaic of dune grasslands and sclerophyllous scrubs (EU codes 2230, 2240, 2260). Seasonal variation of habitat preference was interpreted in light of the different feeding, thermoregulation and reproductive needs of the tortoises. Our results stress the ecological value of EU coastal dune habitats and suggest prioritization of conservation efforts in these ecosystems.

  2. Habitat Evaluation Procedures (HEP) Report : West Beaver Lake, 2004-2005 Technical Report.

    Energy Technology Data Exchange (ETDEWEB)

    Entz, Ray

    2005-02-01

    On September 7, 2004, the Habitat Evaluation Procedure (HEP) was used to determine baseline habitat suitability on the West Beaver Lake property, an acquisition completed by the Kalispel Tribe of Indians in September 2004. Evaluation species and appropriate models include bald eagle, black-capped chickadee, mallard, muskrat, and white-tailed deer. Habitat Suitability Index (HSI) values were visually estimated and agreed upon by all HEP team members. The West Beaver Lake Project provides a total of 103.08 Habitat Units (HUs) for the species evaluated. Emergent wetland habitat provides 7.17 HUs for mallard and muskrat. Conifer forest habitat provides 95.91 HUs for bald eagle, black-capped chickadee, mallard, and white-tailed deer. The objective of using HEP at the West Beaver Lake Project and other protected properties is to document the quality and quantity of available habitat for selected wildlife species. In this way, HEP provides information on the relative value of the same area at future points in time so that the effect of management activities on wildlife habitat can be quantified. When combined with other tools, the baseline HEP will be used to determine the most effective on-site management, restoration, and enhancement actions to increase habitat suitability for targeted species. The same process will be replicated every five years to quantitatively evaluate the effectiveness of management strategies in improving and maintaining habitat conditions while providing additional crediting to BPA for enhanced habitat values.

  3. Habitat-specific foraging of prothonotary warblers: Deducing habitat quality

    Science.gov (United States)

    Lyons, J.E.

    2005-01-01

    Foraging behavior often reflects food availability in predictable ways. For example, in habitats where food availability is high, predators should attack prey more often and move more slowly than in habitats where food availability is low. To assess relative food availability and habitat quality, I studied the foraging behavior of breeding Prothonotary Warblers (Protonotaria citrea) in two forest habitat types, cypress-gum swamp forest and coastal-plain levee forest. I quantified foraging behavior with focal animal sampling and continuous recording during foraging bouts. I measured two aspects of foraging behavior: 1) prey attack rate (attacks per minute), using four attack maneuvers (glean, sally, hover, strike), and 2) foraging speed (movements per minute), using three types of movement (hop, short flight [???1 m], long flight [>1 m]). Warblers attacked prey more often in cypress-gum swamp forest than in coastal-plain levee forest. Foraging speed, however, was not different between habitats. I also measured foraging effort (% time spent foraging) and relative frequency of attack maneuvers employed in each habitat; neither of these variables was influenced by forest type. I conclude that Prothonotary Warblers encounter more prey when foraging in cypress-gum swamps than in coastal-plain levee forest, and that greater food availability results in higher density and greater reproductive success for birds breeding in cypress-gum swamp.

  4. Seagrasses - The forgotton marine habitat

    Digital Repository Service at National Institute of Oceanography (India)

    Jagtap, T.G.; Rodrigues, R.S.

    Seagrasses, a specialized group of flowering plants, submerged in the marine, estuarine, bay and backwater regions of the world. Though seagrass beds are of great ecological and socio economic importance, they are mostly unknown to Indians. Seagrass...

  5. Autonomous Systems: Habitat Automation Element

    Data.gov (United States)

    National Aeronautics and Space Administration — We define a habitat fairly broadly to include any enclosed space that is intended to house people for an extended period of time away from the Earth....

  6. Waterfowl Production and Habitat Survey

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Waterfowl Production and Habitat Survey, conducted by the U.S. Fish and Wildlife Service, became operational in 1955 in the Canadian prairies (strata 26-40). In...

  7. Leatherback Sea Turtle Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for leatherback turtle as designated by Federal Register Vol. 44, No. 17711, March 23, 1979, Rules and Regulations....

  8. Hawksbill Sea Turtle Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for hawksbill turtle as designated by Federal Register Vol. 63, No. 46701, September 2, 1998, Rules and Regulations....

  9. Tidal Creek Sentinel Habitat Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Ecological Research, Assessment and Prediction's Tidal Creeks: Sentinel Habitat Database was developed to support the National Oceanic and Atmospheric...

  10. Riparian Habitat - San Joaquin River

    Data.gov (United States)

    California Department of Resources — The immediate focus of this study is to identify, describe and map the extent and diversity of riparian habitats found along the main stem of the San Joaquin River,...

  11. Endangered Species Act Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Critical habitat (CH) is designated for the survival and recovery of species listed as threatened or endangered under the Endangered Species Act (ESA). Critical...

  12. Habitat--Offshore Monterey, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the habitat map of the seafloor of the Offshore of Monterey map area, California. The vector data file is included in...

  13. Shrub-Scrub Habitat Evaluation

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Conversion of the current shrub-scrub habitats west of Sandpiper Road and north of the Back BayNational Wildlife Refuge, into recreational facilities for a new...

  14. Habitat Evaluation Procedures (HEP) Report : Ladd Marsh, 2001 Technical Report.

    Energy Technology Data Exchange (ETDEWEB)

    Oregon Department of Fish and Wildlife

    2001-10-01

    Since the mid-1980s, the Oregon Department of Fish and Wildlife (ODFW) has been participating in the Bonneville Power Administration's (BPA's) efforts to mitigate for the negative impacts to fish and wildlife resulting from the development and operation of the 7 Columbia Basin Federal Hydropower System. BPA's mitigation obligations were formally recognized and mandated by the Northwest Power Act of 1980 and are guided by the Northwest Power Planning Council's (NWPPC's) Columbia Basin Fish and Wildlife Program. BPA funds fish and wildlife projects throughout the Basin to meet the habitat and population restorative goals and objectives outlined in the NWPPC's Fish and Wildlife Program and to fulfill its mitigation responsibilities under the Power Act. Impacts to wildlife resulting from hydrofacility construction/inundation were estimated using Habitat Evaluation Procedures (HEP) in the mid and late 1980s and are documented in BPA' s Wildlife Loss Assessments (Rasmussen and Wright 1990,a,b,c,d) and in the U.S. Army Corps of Engineers Lower Snake River Wildlife Habitat Compensation Evaluation (ACOE 1991). The loss assessments provided estimates of lost habitat quality and quantity for the target species selected to represent the habitat cover types impacted by hydropower construction/inundation. The NWPPC incorporated these losses into their Fish and Wildlife Program, recognizing them as the unannualized losses attributable to the construction/inundation of the federal hydropower system (NWPPC 1995 and 2000, Table 1 1-4). The HEP methodology is used by wildlife managers within the Columbia Basin to determine habitat values, expressed as Habitat Units, gained through BPA-funded mitigation project work. ODFW and the other Oregon wildlife managers (i.e., U.S. Fish and Wildlife Service, Confederated Tribes of the Warms Springs Reservation of Oregon, Burns Paiute Tribe, and Confederated Tribes of the Umatilla Indian Reservation [CTUIR

  15. Multiscale Modeling of Powder Bed-Based Additive Manufacturing

    Science.gov (United States)

    Markl, Matthias; Körner, Carolin

    2016-07-01

    Powder bed fusion processes are additive manufacturing technologies that are expected to induce the third industrial revolution. Components are built up layer by layer in a powder bed by selectively melting confined areas, according to sliced 3D model data. This technique allows for manufacturing of highly complex geometries hardly machinable with conventional technologies. However, the underlying physical phenomena are sparsely understood and difficult to observe during processing. Therefore, an intensive and expensive trial-and-error principle is applied to produce components with the desired dimensional accuracy, material characteristics, and mechanical properties. This review presents numerical modeling approaches on multiple length scales and timescales to describe different aspects of powder bed fusion processes. In combination with tailored experiments, the numerical results enlarge the process understanding of the underlying physical mechanisms and support the development of suitable process strategies and component topologies.

  16. Vacant Nests and Other Factors Influencing Nest Site Selection of Birds of Prey Based on Case Studies in Forest Habitats in the Forest-Steppe and Steppe Zones of Eastern Ukraine

    Directory of Open Access Journals (Sweden)

    Stanislav G. Viter

    2015-12-01

    Full Text Available Our study was conducted in 2003–2012 in Eastern Ukraine, in the basin of the Seversky Donets river. The total surveyed area was ca. 900 km2 of nesting habitats suitable for raptors. A total of 69 vacant nests were found, i.e. 33.2 % of the total number of nests (208. Nests occupied by recipient species, i.e. the so-called ‘effective nest pool’, were 23–24, i.e. 33.3–34.7 % of the pool of available nests. Up to 25 % of all pairs of raptors depend on the availability of vacant nests of heterospecifics. Ravens (Corvus corax are the most significant donors of nests: 42.5 % of the pool of available nests is built by this species, and more than 60 % of them are occupied by recipient species. Common Buzzard (Buteo buteo comes second with 26.09 and 58.3 %, respectively. The most common recipients of nests are Hobbies (Falco subbuteo, Common Kestrel (Falco tinnunculus and Booted Eagles (Hieraaetus pennatus. The most significant factors that govern occupation of vacant nests by recipient species are: availability of nests in the marginal zone of forest plots, i.e. within 500 m from the forest edge, large distance from human settlements (>1500 m, presence of nests located on trees in the canopy storey, and mature and submature age of forest stands. For seven species considered in our research (n=227, the most important factors were position of nests, in the forest canopy layer, no logging activity within300 m of the nest, no regular human disturbance, and presence of “windows” in the canopy made by fallen trees.

  17. Asotin Creek Instream Habitat Alteration Projects: 1998 Habitat Evaluation Surveys.

    Energy Technology Data Exchange (ETDEWEB)

    Bumgarner, Joseph D.

    1999-03-01

    The Asotin Creek Model Watershed Master Plan was completed 1994. The plan was developed by a landowner steering committee for the Asotin County Conservation District (ACCD), with technical support from the various Federal, State and local entities. Actions identified within the plan to improve the Asotin Creek ecosystem fall into four main categories, (1) Stream and Riparian, (2) Forestland, (3) Rangeland, and (4) Cropland. Specific actions to be carried out within the stream and in the riparian area to improve fish habitat were, (a) create more pools, (b) increase the amount of large organic debris (LOD), (c) increase the riparian buffer zone through tree planting, and (d) increase fencing to limit livestock access; additionally, the actions are intended to stabilize the river channel, reduce sediment input, and protect private property. Fish species of main concern in Asotin Creek are summer steelhead (Oncorhynchus mykiss), spring chinook (Oncorhynchus tshawytscha), and bull trout (Salvelinus confluentus). Spring chinook in Asotin Creek are considered extinct (Bumgarner et al. 1998); bull trout and summer steelhead are below historical levels and are currently as ''threatened'' under the ESA. In 1998, 16 instream habitat projects were planned by ACCD along with local landowners. The ACCD identified the need for a more detailed analysis of these instream projects to fully evaluate their effectiveness at improving fish habitat. The Washington Department of Fish and Wildlife's (WDFW) Snake River Lab (SRL) was contracted by the ACCD to take pre-construction measurements of the existing habitat (pools, LOD, width, depth, etc.) within each identified site, and to eventually evaluate fish use within these sites. All pre-construction habitat measurements were completed between 6 and 14 July, 1998. 1998 was the first year that this sort of evaluation has occurred. Post construction measurements of habitat structures installed in 1998, and fish

  18. The role of habitat filtering in the leaf economics spectrum and plant susceptibility to pathogen infection

    Science.gov (United States)

    Welsh, Miranda E; Cronin, James P.; Mitchell, Charles E.

    2016-01-01

    1.The Leaf Economics Spectrum (LES) describes global covariation in the traits of plant leaves. The LES is thought to arise from biophysical constraints and habitat filtering (ecological selection against unfit trait combinations along environmental gradients). However, the role of habitat filtering in generating the LES has not been tested experimentally.

  19. Habitat Fragmentation and Native Bees: a Premature Verdict?

    Directory of Open Access Journals (Sweden)

    James H. Cane

    2001-06-01

    Full Text Available Few studies directly address the consequences of habitat fragmentation for communities of pollinating insects, particularly for the key pollinator group, bees (Hymenoptera: Apiformes. Bees typically live in habitats where nesting substrates and bloom are patchily distributed and spatially dissociated. Bee studies have all defined habitat fragments as remnant patches of floral hosts or forests, overlooking the nesting needs of bees. Several authors conclude that habitat fragmentation is broadly deleterious, but their own data show that some native species proliferate in sampled fragments. Other studies report greater densities and comparable diversities of native bees at flowers in some fragment size classes relative to undisrupted habitats, but find dramatic shifts in species composition. Insightful studies of habitat fragmentation and bees will consider fragmentation, alteration, and loss of nesting habitats, not just patches of forage plants, as well as the permeability of the surrounding matrix to interpatch movement. Inasmuch as the floral associations and nesting habits of bees are often attributes of species or subgenera, ecological interpretations hinge on authoritative identifications. Study designs must accommodate statistical problems associated with bee community samples, especially non-normal data and frequent zero values. The spatial scale of fragmentation must be appreciated: bees of medium body size can regularly fly 1–2 km from nest site to forage patch. Overall, evidence for prolonged persistence of substantial diversity and abundances of native bee communities in habitat fragments of modest size promises practical solutions for maintaining bee populations. Provided that reserve selection, design, and management can address the foraging and nesting needs of bees, networks of even small reserves may hold hope for sustaining considerable pollinator diversity and the ecological services pollinators provide.

  20. Green sturgeon physical habitat use in the coastal Pacific Ocean.

    Directory of Open Access Journals (Sweden)

    David D Huff

    Full Text Available The green sturgeon (Acipenser medirostris is a highly migratory, oceanic, anadromous species with a complex life history that makes it vulnerable to species-wide threats in both freshwater and at sea. Green sturgeon population declines have preceded legal protection and curtailment of activities in marine environments deemed to increase its extinction risk. Yet, its marine habitat is poorly understood. We built a statistical model to characterize green sturgeon marine habitat using data from a coastal tracking array located along the Siletz Reef near Newport, Oregon, USA that recorded the passage of 37 acoustically tagged green sturgeon. We classified seafloor physical habitat features with high-resolution bathymetric and backscatter data. We then described the distribution of habitat components and their relationship to green sturgeon presence using ordination and subsequently used generalized linear model selection to identify important habitat components. Finally, we summarized depth and temperature recordings from seven green sturgeon present off the Oregon coast that were fitted with pop-off archival geolocation tags. Our analyses indicated that green sturgeon, on average, spent a longer duration in areas with high seafloor complexity, especially where a greater proportion of the substrate consists of boulders. Green sturgeon in marine habitats are primarily found at depths of 20-60 meters and from 9.5-16.0°C. Many sturgeon in this study were likely migrating in a northward direction, moving deeper, and may have been using complex seafloor habitat because it coincides with the distribution of benthic prey taxa or provides refuge from predators. Identifying important green sturgeon marine habitat is an essential step towards accurately defining the conditions that are necessary for its survival and will eventually yield range-wide, spatially explicit predictions of green sturgeon distribution.

  1. Materials performance in fluidized-bed air heaters

    Energy Technology Data Exchange (ETDEWEB)

    Natesan, K.; Podolski, W.

    1991-12-01

    Development of cogeneration systems that involve combustion of coal in a fluidized bed and use of air heaters to generate hot air for turbine systems has been in progress for a number of years. The US Department of Energy (DOE) sponsored the Atmospheric Fluidized-Bed Cogeneration Air Heater Experiment (ACAHE) to assess the performance of various heat exchanger materials and establish confidence in the resultant designs of fluidized-bed-combustion air heater systems. Westinghouse Electric Corporation, in association with Babcock & Wilcox, Foster Wheeler, and ABB/Combustion Engineering, prepared specifications and hardware for the ACAHE. Argonne National Laboratory, through a contract with the Rocketdyne Division of Rockwell International, conducted tests in the DOE 1.8 {times} 1.8 m atmospheric fluidized-bed combustion facility in El Segundo, California. This paper presents an assessment of the materials performance in fluidized bed environments and examines guidelines for materials selection on the basis of corrosion resistance in air and in combustion environments, mechanical properties, fabricability/thermal stability, and cost.

  2. Materials performance in fluidized-bed air heaters

    Energy Technology Data Exchange (ETDEWEB)

    Natesan, K.; Podolski, W.

    1991-12-01

    Development of cogeneration systems that involve combustion of coal in a fluidized bed and use of air heaters to generate hot air for turbine systems has been in progress for a number of years. The US Department of Energy (DOE) sponsored the Atmospheric Fluidized-Bed Cogeneration Air Heater Experiment (ACAHE) to assess the performance of various heat exchanger materials and establish confidence in the resultant designs of fluidized-bed-combustion air heater systems. Westinghouse Electric Corporation, in association with Babcock Wilcox, Foster Wheeler, and ABB/Combustion Engineering, prepared specifications and hardware for the ACAHE. Argonne National Laboratory, through a contract with the Rocketdyne Division of Rockwell International, conducted tests in the DOE 1.8 {times} 1.8 m atmospheric fluidized-bed combustion facility in El Segundo, California. This paper presents an assessment of the materials performance in fluidized bed environments and examines guidelines for materials selection on the basis of corrosion resistance in air and in combustion environments, mechanical properties, fabricability/thermal stability, and cost.

  3. The migration game in habitat network: the case of tuna

    DEFF Research Database (Denmark)

    Mariani, Patrizio; Krivan, Vlastimil; MacKenzie, Brian;

    2016-01-01

    migration in direction of increasing fitness should lead to the ideal free distribution (IFD) which is the evolutionary stable strategy of the habitat selection game. We introduce a migration game which focuses on migrating dynamics leading to the IFD for age-structured populations and in time varying...

  4. Temporally dynamic habitat suitability predicts genetic relatedness among caribou.

    Science.gov (United States)

    Yannic, Glenn; Pellissier, Loïc; Le Corre, Maël; Dussault, Christian; Bernatchez, Louis; Côté, Steeve D

    2014-10-01

    Landscape heterogeneity plays a central role in shaping ecological and evolutionary processes. While species utilization of the landscape is usually viewed as constant within a year, the spatial distribution of individuals is likely to vary in time in relation to particular seasonal needs. Understanding temporal variation in landscape use and genetic connectivity has direct conservation implications. Here, we modelled the daily use of the landscape by caribou in Quebec and Labrador, Canada and tested its ability to explain the genetic relatedness among individuals. We assessed habitat selection using locations of collared individuals in migratory herds and static occurrences from sedentary groups. Connectivity models based on habitat use outperformed a baseline isolation-by-distance model in explaining genetic relatedness, suggesting that variations in landscape features such as snow, vegetation productivity and land use modulate connectivity among populations. Connectivity surfaces derived from habitat use were the best predictors of genetic relatedness. The relationship between connectivity surface and genetic relatedness varied in time and peaked during the rutting period. Landscape permeability in the period of mate searching is especially important to allow gene flow among populations. Our study highlights the importance of considering temporal variations in habitat selection for optimizing connectivity across heterogeneous landscape and counter habitat fragmentation. PMID:25122223

  5. Differences in the structure and functioning of two communities: Frondose and turf-forming macroalgal dominated habitats.

    Science.gov (United States)

    M Martins, Gustavo; Hipólito, Cláudia; Parreira, Filipe; C L Prestes, Afonso; Dionísio, Maria A; N Azevedo, José M; Neto, Ana I

    2016-05-01

    In many coastal regions, vegetated habitats (e.g. kelps forests, seagrass beds) play a key role in the structure and functioning of shallow subtidal reef ecosystems, by modifying local environmental conditions and by providing food and habitat for a wide range of organisms. In some regions of the world, however, such idiosyncratic ecosystems are largely absent and are often replaced by less notable ecosystem formers. In the present study, we empirically compared the structure and functioning of two distinct shallow-water habitats present in the Azores: one dominated by smaller frondose brown macroalgae (Dictyotaceae and Halopteris) and one dominated by low-lying turfs. Two replicated areas of each habitat were sampled at two different times of the year, to assess spatial and temporal consistency of results. Habitats dominated by small fronds were significantly (ca. 3 times) more productive (when standardized per algal mass) compared to the turf-dominated habitats, and supported a distinct assemblage (both in terms of composition and abundance) of associated macrofauna. Unlike other well-known and studied vegetated habitats (i.e. kelp forests), however, no effects of habitat were found on the structure of benthonic fish assemblages. Results were spatially and temporally consistent suggesting that, in warmer temperate oceans, habitats dominated by species of smaller frondose brown algae can also play an important role in the structure and functioning of subtidal communities and may, to a certain extent, be considered analogous to other well-known vegetated habitats around the world (i.e. kelp forests, seagrass beds). PMID:27035366

  6. Population resource and habitat selection in summer of black knobby newt ( Tylototriton asperrimus) in surrounding areas of Houhe National Nature Reserve, Hubei Province,China%后河自然保护区周边地区细痣疣螈资源及夏季生境选择

    Institute of Scientific and Technical Information of China (English)

    孙守甲; 戴琦; 戴宗兴; 张洪茂; 龚仁虎; 杜建锋; 邹红山; 聂才爱

    2011-01-01

    2010年7-8月在后河国家级自然保护区及周边地区,运用样方法对细痣疣螈(Tylototriton asperrimus)的种群数量、分布及栖息生境进行了调查,并利用生境喜好系数和主成分分析法对细痣疣螈的夏季生境选择进行了分析.结果发现:细痣疣螈主要分布于与后河自然保护区毗邻的长乐坪镇及其附近区域,栖息地海拔450 ~ 1400 m,分布面积约550km2;在调查的103个样方中,有18个样方共发现细痣疣螈68条,种群数量较少;通过生境偏好系数分析发现,细痣疣螈偏好选择的微生境为:距小型静水塘(水体面积≤20 m2)51~100 m、距居民点101 ~500 m、距农田≤50 m、距道路≤100 m、草本盖度61% ~80%、草本高度21 ~40 cm、地表湿度61% ~80%、地表温度24℃~27℃的枯枝腐叶和草地生境;主成分分析表明,温度、植被、水体类型、人为干扰和食物是影响细痣疣螈夏季生境选择的主要因子.%By using sampling plot method, an investigation was conducted on the population resource and habitat selection in summer of black knobby newt ( Tylototriton asperrimus) in the Houhe National Nature Reserve and its surroundings areas in July-August 2010, and the Favorite index P and principal component analysis were used to study the micro-habitat selection in summer of T. Asperrimus. T. Asperrimus was mainly distributed in the Changleping Town and its nearby areas adjacent to the Reserve, 450-1400 m in altitude and about 550 km2 in size. A total of 68 T. Asperrimus individuals were collected in 18 of 103 investigated plots, suggesting that there existed a few T. Asperrimus populations. Favorite index P analysis indicated that the favorite micro-habitats of T. Asperrimus were the grasslands with litters, which were 51-100 m away from the stagnant pounds with a size of ≤20 m2, 61% -80% coverage, 21-40 cm vegetation height, 61%-80% surface humidity, 24 ℃ -27 ℃ surface temperature, ≤50 m

  7. A NEW HABITAT CLASSIFICATION AND MANUAL FOR STANDARDIZED HABITAT MAPPING

    Directory of Open Access Journals (Sweden)

    A. KUN

    2007-01-01

    Full Text Available Today the documentation of natural heritage with scientific methods but for conservation practice – like mapping of actual vegetation – becomes more and more important. For this purpose mapping guides containing only the names and descriptions of vegetation types are not sufficient. Instead, new, mapping-oriented vegetation classification systems and handbooks are needed. There are different standardised systems fitted to the characteristics of a region already published and used successfully for surveying large territories. However, detailed documentation of the aims and steps of their elaboration is still missing. Here we present a habitat-classification method developed specifically for mapping and the steps of its development. Habitat categories and descriptions reflect site conditions, physiognomy and species composition as well. However, for species composition much lower role was given deliberately than in the phytosociological systems. Recognition and mapping of vegetation types in the field is highly supported by a definition, list of subtypes and list of ‘types not belonging to this habitat category’. Our system is two-dimensional: the first dimension is habitat type, the other is naturalness based habitat quality. The development of the system was conducted in two steps, over 200 mappers already tested it over 7000 field days in different projects.

  8. Habitat Suitability Index Models: Bigmouth Buffalo

    Science.gov (United States)

    Edwards, Elizabeth A.

    1983-01-01

    A review and synthesis of existing information were used to develop riverine and lacustrine habitat models for Bigmouth buffalo (Ictiobus cyprinellus), a freshwater fish. The models are scaled to produce an indices of habitat suitability between 0 (unsuitable habitat) and 1 (optimally suitable habitat) for freshwater areas of the continental United States. Other habitat suitability models found in the literature are also included. Habitat suitability indices (HSI's) are designed for use with the habitat evaluation procedures developed by the U.S. Fish and Wildlife Service.

  9. Character of shell beds flanking Herod Point shoal, southeastern Long Island Sound, New York

    Science.gov (United States)

    Poppe, L.J.; Williams, S.J.; Babb, Ivar G.

    2011-01-01

    High biogenic productivity, strong tidal currents, shoal topography, and short transport distances combine to favor shell-bed formation along the lower flanks of a cape-associated shoal off Herod Point on Long Island, New York. This shell bed has a densely packed, clast-supported fabric composed largely of undegraded surf clam (Spisula solidissima) valves. It is widest along the central part of the western flank of the shoal where topographic gradients are steep and a stronger flood tide results in residual flow. The bed is narrower and thinner toward the landward margins where currents are too weak to transport larger valves and topographic gradients are gentle, limiting bed-load transport mechanisms by which the shells are concentrated. Reconnaissance mapping off Roanoke Point suggests that shell beds are also present at the other cape-associated shoals off northeastern Long Island, where relatively similar geomorphic and oceanographic conditions exist. These shell beds are important to the Long Island Sound ecosystem because they provide complex benthic habitats of rough and hard substrates at the boundary between the muddy basin floor and mobile sand of the shoals. ?? 2011, the Coastal Education & Research Foundation (CERF).

  10. Improving Operability of Lab-Scale Spouted Bed Using Global Stochastic Optimization

    Directory of Open Access Journals (Sweden)

    Dr.Ghanim.M. Alwan

    2015-01-01

    Full Text Available A spouted bed is a special case of fluidization. It is an effective means of contacting gas with coarse solid particles .Gas-solid spouted beds are either cylindrical bed with cone base or the whole bed is in a cone shape where the gas enters as a jet. The gas forms a spout region that carries the solids upward in a diluted phase that forms a fountain at the top of the bed where the solids fall down and move downward in the annular region. Performance of gas-solid spouted bed benefit from solids uniformity structure with lower pressure drop (PD.Dropping of PD across a spouted bed could reduce the dissipated pumping energy and improve stability and uniformity of solid particles. The objective of this work is to study and selecting best operating conditions that could minimize PD across the bed. Optimization technique is a powerful tool would guide the experimental work and reduce the risk and cost for design and operation Hence, PD is to be considered as objective function of the optimization process .Three selected decision variables are affecting objective function. These decision variables are gas velocity, particle density and particle diameter. Steady-state measurements were carried out in a narrow 3-inch (0.076 m ID cylindrical spouted bed made of Plexiglas that used 60° conical shape base. Radial concentration of particles (glass and steel beads at various bed heights under different flow patterns were measured using sophisticated optical probes. A superficial velocity of air ranging from 0.74 to 1.0 m/s .PD was measured across the bed by high accuracy pressure transducers. Stochastic Genetic Algorithm (GA has found suitable global search for the non-linear hybrid spouted bed. Optimum results could select the best operating conditions for high-performance and stable conditions. Uniformity and stability of solid particles in the bed would enhance hydrodynamic parameters, heat and mass transfer. Best Operability of the bed was observed with

  11. Stratum energy of coal-bed gas reservoir and their control on the coal-bed gas reservoir formation

    Institute of Scientific and Technical Information of China (English)

    WU; CaiFang; QIN; Yong; FU; XueHai

    2007-01-01

    Stratum energy of coal-bed gas reservoir, including coal-radix flexibility energy, groundwater flexibility energy and gas flexibility energy (hereinafter "three energy"), depends on the energy homeostasis system, the core process of which is the effective transfer of energy and the geological selective process. Combining with the mechanics experimentations of coal samples, different flexibility energy has been analyzed and researched quantificationally, and a profound discussion to their controls on the coal-bed gas reservoir formation has been made. It is shown that when gas reservoir is surrounded by edge water and bottom water, the deposited energy in the early phase of forming gas reservoir is mostly coal-radix and gas flexibility energy, but the effect of groundwater flexibility energy increases while water-body increases. The deposited energy in the middle and later phase of forming gas reservoir is mostly gas flexibility energy, which is greater than 80% of all deposited energy. In the whole process, larger groundwater body exerts greater influences on gas accumulation. The paper indicated that higher stratum energy is more propitious to forming coal-bed gas reservoir. And higher coal-radix flexibility energy and gas flexibility energy are more propitious to higher yield of gas reservoirs, while higher groundwater flexibility energy is more propitious to stable yield of gas reservoirs. Therefore, the key to evaluating the coal-bed gas reservoir formation is the stratum energy of coal-bed gas reservoir.

  12. EMERGING TECHNOLOGY BULLETIN: SPOUTED BED REACTOR

    Science.gov (United States)

    The Spouted Bed Reactor (SBR) technology utilizes the unique attributes of the "spouting " fluidization regime, which can provide heat transfer rates comparable to traditional fluid beds, while providing robust circulation of highly heterogeneous solids, concurrent with very agg...

  13. [Historical analysis of the hospital bed].

    Science.gov (United States)

    Fajardo-Ortiz, Guillermo; Fajardo-Dolci, Germán

    2010-01-01

    Until now the bed has been the basic physical resource in hospitals. This type of furniture has served to study and treat patients, through out the centuries it has undergone changes in the materials they are made of dimensions, functionality, accessories, aesthetic, and design. The hospital bed history is not well known, there are thousands of documents about the evolution of hospitals, but not enough is known about hospital beds, a link between the past and the present. The medical, anthropological, technological, social, and economic dynamics and knowledge have produced a variety of beds in general and hospital beds in particular. From instinctive, rustic, poor and irregular "sites" that have differed in shape and size they had evolved into ergonomic equipment. The history of the hospital bed reflects the culture, techniques and human thinking. Current hospital beds include several types: for adults, for children, for labor, for intensive therapy, emergency purposes, census and non census beds etc.

  14. Chinese Bedding Technology Standard under Drafting

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    National Home Textile Standardization Technology Committee(NHTSTC)set up its Bedding Branch Committee. This will promote the work of Chinese bedding technology standardization and a symbol that China step up to meet the

  15. Habitat Suitability Index Models: Swamp Rabbit

    Science.gov (United States)

    Allen, Arthur W.

    1985-01-01

    A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the swamp rabbit (Sylvilagus aquaticus). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.

  16. Habitat Suitability Index Models: Eastern wild turkey

    Science.gov (United States)

    Schroeder, Richard L.

    1985-01-01

    A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the eastern wild turkey (Meleagris gallopavo sylvestris). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.

  17. 斑翅肩花蝽生物学特性、生境及食性选择%The biological characteristics, habitat and food selection of Tetraphleps galchanoides ( Hemiptera: Anthocoridae)

    Institute of Scientific and Technical Information of China (English)

    李立; 虞国跃; Tom J.MCAVOY; Richard C.REARDON; 吴云; Scott M.SALOM; 和景福

    2011-01-01

    斑翅肩花蝽Tetraphleps galchanoides Ghauri是铁杉球蚜Adeges tsugae Annand(hemlock woolly adelgid)的重要天敌昆虫.在云南省兰坪县天生桥林区通过实验室和林间的饲养观察与测定、林间线路调查等方法,研究了斑翅肩花蝽的生物学特性、生境及食性选择,并描述各虫态形态特征.斑翅肩花蝽在该林区一年发生2代,无世代重叠,寿命长.第1代(5月下旬至10月下旬)卵期13.8±1.6 d,若虫期97.6±7.4 d,成虫期55.2±4.7 d;第2代(¨月中旬至翌年4月下旬)卵期11.3±1.1 d,若虫期105.7±8.5 d,成虫期60.4±5.3 d.若虫共5龄,以5龄若虫在云南铁杉Tsuga dumosa枝条树皮裂缝下或枯枝落叶层内越冬.雌雄成虫性比8.5∶1,雌雄成虫飞行缓慢,其飞行活动主要受到交尾、产卵、捕食铁杉球蚜补充营养的影响,多在树冠下层活动.该林区的斑翅肩花蝽最适生境选择:海拔为2 851~2 980 m,云南铁杉密度为13.3~15.5株/100m、郁闭度为0.61~0.70.以寄主铁杉球蚜及附近常见的冷杉球蚜Aphrastasia pectinatae(Cholodkovsky)、华山松球蚜Pineus armandicola Zhang和落叶松球蚜Adelges laricis Vall为食物进行选择性试验,结果表明,斑翅肩花蝽对这4种球蚜的选择性存在显著差异,最喜好捕食铁杉球蚜,可成为生物防治铁杉球蚜的主要天敌之一.%Tetraphleps galchanoides Ghauri is an important predator of the hemlock woolly adelgid (HWA), Adelges tsugae Annand, in China. Its biology, habitats and prey habit were studied through breeding observation in the laboratory and field investigation. It occurs 2 generations per year without generation overlapping in Tianshengqiao Forest Farm, Lanping County, Yunnan Province. The 1st generation occurs in late May to late October. Egg period lasts 13.8± 1.6 d, nymph period lasts 97.6 ±7.4 d, and adult period lasts 55.2 ± 4.7 d. The 2nd generation occurs in mid November to late April of next year. Egg period lasts 11.3 ± 1.1 d

  18. Fluidized Bed Reactor as Solid State Fermenter

    OpenAIRE

    Krishnaiah, K.; Janaun, J.; Prabhakar, A.

    2005-01-01

    Various reactors such as tray, packed bed, rotating drum can be used for solid-state fermentation. In this paper the possibility of fluidized bed reactor as solid-state fermenter is considered. The design parameters, which affect the performances are identified and discussed. This information, in general can be used in the design and the development of an efficient fluidized bed solid-state fermenter. However, the objective here is to develop fluidized bed solid-state fermenter for palm kerne...

  19. An update on SeaBED: a TesBED for validating subsurface aquatic hyperspectral remote sensing algorithms

    Science.gov (United States)

    Goodman, James A.; Vélez-Reyes, Miguel; Rosario-Torres, Samuel

    2008-10-01

    SeaBED is an integrated data set and testing infrastructure for researchers to validate subsurface aquatic remote sensing algorithms. The purpose behind developing SeaBED is to collect multiple levels of image, field, and laboratory data with which to validate physical models, inversion algorithms, feature extraction tools and classification methods for subsurface aquatic sensing using hyperspectral imaging. The focus of this testbed facility is a field site located on Enrique Reef in southwestern Puerto Rico. This field site, which includes a heterogeneous mixture of both coral reef and seagrass habitats, offers a well defined system for evaluating analysis techniques under natural environmental conditions. Data produced from the field site currently includes airborne, satellite, and field-level hyperspectral and multispectral images, in situ spectral signatures, and water bio-optical properties. This data provides a valuable combination of sensing imagery and fully characterized ground truth information for developing and validating remote sensing algorithms. A major accomplishment for SeaBED was the collection of high-resolution hyperspectral imagery and associated ground truth of the near shore reefs and coastal ecosystems in southwestern Puerto Rico in 2007. The mission included 1740 km2 of imagery acquired at 4 m spatial resolution, with 110 km2 enhanced coverage of four science areas at 1, 2, 4 and 8 m spatial resolutions to facilitate investigation of spatial scaling issues and the testing of subsurface unmixing algorithms. We present an overview of SeaBED and also describe particulars of the 2007 data collection campaign, including both image acquisition and field data collection efforts.

  20. Bed Bug Education for School Maintenance

    Science.gov (United States)

    Henriksen, Missy

    2012-01-01

    Bed bugs are a growing problem, not only in homes and hotels, but also in schools and colleges. Facility administrators and staff need to understand the bed bug resurgence and develop best practices to deal with an infestation. In this article, the author offers tips for preventing and treating bed bugs in school and university settings.

  1. 21 CFR 868.5180 - Rocking bed.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Rocking bed. 868.5180 Section 868.5180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5180 Rocking bed. (a) Identification. A rocking bed is a...

  2. Thermal energy storage systems using fluidized bed heat exchangers

    Science.gov (United States)

    Ramanathan, V.; Weast, T. E.; Ananth, K. P.

    1980-01-01

    The viability of using fluidized bed heat exchangers (FBHX) for thermal energy storage (TES) in applications with potential for waste heat recovery was investigated. Of the candidate applications screened, cement plant rotary kilns and steel plant electric arc furnaces were identified, via the chosen selection criteria, as having the best potential for successful use of FBHX/TES system. A computer model of the FBHX/TES systems was developed and the technical feasibility of the two selected applications was verified. Economic and tradeoff evaluations in progress for final optimization of the systems and selection of the most promising system for further concept validation are described.

  3. Review of acute cancer beds.

    LENUS (Irish Health Repository)

    Evans, D S

    2012-01-01

    A review of admissions to cancer services at University Hospital Galway (UHG) was undertaken to assess the appropriateness of hospital usage. All cancer specialty patients admitted from 26-28 May 2009 were reviewed (n = 82). Chi square tests, Exact tests, and One-way ANOVA were utilised to analyse key issues emerging from the data. Fifty (61%) were classified as emergencies. Twenty three (67%) occupied a designated cancer bed with 24 (30%) in outlying non-oncology wards. The mean length of stay was 29.3 days. Possible alternatives to admission were identified for 15 (19%) patients. There was no evidence of discharge planning for 50 (60%) admissions. There is considerable potential to make more appropriate utilisation of UHG for cancer patients, particularly in terms of reducing bed days and length of stay and the proportion of emergency cancer admissions, and further developing integrated systems of discharge planning.

  4. Distribution of fish in seagrass, mangroves and coral reefs: life-stage dependent habitat use in Honduras.

    Science.gov (United States)

    Jaxion-Harm, Jessica; Saunders, James; Speight, Martin R

    2012-06-01

    Many coral reef fish exhibit habitat partitioning throughout their lifetimes. Such patterns are evident in the Caribbean where research has been predominantly conducted in the Eastern region. This work addressed the paucity of data regarding Honduran reef fish distribution in three habitat types (seagrass, mangroves, and coral reefs), by surveying fish on the islands of Utila and Cayos Cochinos off the coast of Honduras (part of the Mesoamerican barrier reef). During July 2nd - Aug 27th 2007 and June 22nd - Aug 17th, 2008, visual surveys (SCUBA and snorkel) were performed in belt transects in different areas: eleven coral reef, six seagrass beds, and six mangroves sites. Juvenile densities and total habitat surface area were used to calculate nursery value of seagrass and mangroves. A total of 113 fish species from 32 families were found during underwater surveys. Multi-dimensional analyses revealed distinct clusters of fish communities in each habitat type by separating fish associated with seagrass beds, mangroves, and coral reefs. Coral reefs showed the highest mean fish species richness and were dominated by adult fish, while juvenile fish characterized seagrass beds and mangrove sites. Habitat use differed widely at the fish species level. Scarus iseri (Striped Parrotfish), the most abundant fish in this study, were found in all three habitat types, while Lutjanus apodus (Schoolmaster Snapper) juveniles were located primarily in mangroves before migrating to coral reefs. Many species used seagrass beds and mangroves as nurseries; however, the nursery value could not be generalized at the family level. Furthermore, for some fish species, nursery value varied between islands and sites. Our results suggest that connectivity of seagrass, mangrove, and coral reef sites at a species and site levels, should be taken into consideration when implementing policy and conservation practices.

  5. Ship Sensor Observations for Islands in the Stream 2002 - Deep Reef Habitat - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hourly measurements made by selected ship sensors on the R/V Seward Johnson during the 2002 "Islands in the Stream - Deep Reef Habitat" expedition sponsored by the...

  6. Trapping Triatominae in Silvatic Habitats

    Directory of Open Access Journals (Sweden)

    Noireau François

    2002-01-01

    Full Text Available Large-scale trials of a trapping system designed to collect silvatic Triatominae are reported. Live-baited adhesive traps were tested in various ecosystems and different triatomine habitats (arboreal and terrestrial. The trials were always successful, with a rate of positive habitats generally over 20% and reaching 48.4% for palm trees of the Amazon basin. Eleven species of Triatominae belonging to the three genera of public health importance (Triatoma, Rhodnius and Panstrongylus were captured. This trapping system provides an effective way to detect the presence of triatomines in terrestrial and arboreal silvatic habitats and represents a promising tool for ecological studies. Various lines of research are contemplated to improve the performance of this trapping system.

  7. Loss and modification of habitat

    Science.gov (United States)

    Lemckert, Francis; Hecnar, Stephen; Pilliod, David S.; Wilkinson, John W.; Heatwole, Harold

    2012-01-01

    Amphibians live in a wide variety of habitats around the world, many of which have been modified or destroyed by human activities. Most species have unique life history characteristics adapted to specific climates, habitats (e.g., lentic, lotic, terrestrial, arboreal, fossorial, amphibious), and local conditions that provide suitable areas for reproduction, development and growth, shelter from environmental extremes, and predation, as well as connectivity to other populations or habitats. Although some species are entirely aquatic or terrestrial, most amphibians, as their name implies, lead a dual life and require a mosaic of habitats in both aquatic and terrestrial ecosystems. With over 6 billion people on Earth, most species are now persisting in habitats that have been directly or indirectly influenced by human activities. Some species have disappeared where their habitats have been completely destroyed, reduced, or rendered unsuitable. Habitat loss and degradation are widely considered by most researchers as the most important causes of amphibian population decline globally (Barinaga 1990; Wake and Morowitz 1991; Alford and Richards 1999). In this chapter, a background on the diverse habitat requirements of amphibians is provided, followed by a discussion of the effects of urbanization, agriculture, livestock grazing, timber production and harvesting, fire and hazardous fuel management, and roads on amphibians and their habitats. Also briefly discussed is the influence on amphibian habitats of natural disturbances, such as extreme weather events and climate change, given the potential for human activities to impact climate in the longer term. For amphibians in general, microhabitats are of greater importance than for other vertebrates. As ectotherms with a skin that is permeable to water and with naked gelatinous eggs, amphibians are physiologically constrained to be active during environmental conditions that provide appropriate body temperatures and adequate

  8. Bed bathing patients in hospital

    OpenAIRE

    L Downey; Lloyd, Hilary

    2008-01-01

    There are a number of circumstances that may affect an individual's ability to maintain personal hygiene. Hospitalised patients, and in particular those who are bedridden, may become dependent on nursing staff to carry out their hygiene needs. Assisting patients to maintain personal hygiene is a fundamental aspect of nursing care. However, it is a task often delegated to junior or newly qualified staff. This article focuses on the principles of bed bathing patients in hospital, correct proced...

  9. THE BAUXITES AND JELAR - BEDS

    Directory of Open Access Journals (Sweden)

    Krešimir Sakač

    1993-12-01

    Full Text Available Minor bauxite deposits and occurrences were formed in technically disturbed environments in the middle part of the Adriatic geotectonic unit in Dinarides, contemporary with the clastic Jelar-beds in the Late Lutetian time. Uneven chemical composition of these Eocene bauxites, their sporadic occurrences in developed paleorelief as well as characteristic petrographic composition of the immediate overlying rocks point out at different genetical conditions (the paper is published in Croatian.

  10. Solids mixing in spouted beds

    OpenAIRE

    Cook, H. H.; Bridgwater, J.; Professor J. Bridgwater

    1981-01-01

    Many industrial processes require contact between particles and a fluid or spray in order to effect drying, coating or granulation. One device capable of contacting fluid and particles efficiently is a spouted bed in which a jet of fluid is injected into solid particles. This forms an open channel or spout and induces material circulation in a downward moving annulus. For the continuous throughput of solids, knowledge is required of the mixing and particle motions within th...

  11. The statistical character of packed-bed heat transport properties

    OpenAIRE

    Wijngaarden, R.J.; Westerterp, K. R.

    1992-01-01

    Packed beds are essentially heterogeneous on a pellet scale. For random packed beds this heterogeneity causes a statistical character both on a pellet and bed scale. We discuss experimental results which deal with bed-scale statistics.

  12. Method and apparatus for a combination moving bed thermal treatment reactor and moving bed filter

    Energy Technology Data Exchange (ETDEWEB)

    Badger, Phillip C.; Dunn, Jr., Kenneth J.

    2015-09-01

    A moving bed gasification/thermal treatment reactor includes a geometry in which moving bed reactor particles serve as both a moving bed filter and a heat carrier to provide thermal energy for thermal treatment reactions, such that the moving bed filter and the heat carrier are one and the same to remove solid particulates or droplets generated by thermal treatment processes or injected into the moving bed filter from other sources.

  13. Spartina anglica eradication experiment and in situ monitoring assess structuring strength of habitat complexity on marine macrofauna at high tidal level

    Science.gov (United States)

    Cottet, Maud; de Montaudouin, Xavier; Blanchet, Hugues; Lebleu, Pascal

    2007-02-01

    The cordgrass Spartina anglica is an introduced species that tends to invade sheltered sand and mudflats, at the upper low marsh level. In Arcachon Bay, a lagoon in South West of France, the cordgrass can also replace Zostera noltii beds. The consequence of cordgrass presence on macrobenthic fauna was estimated and compared to adjacent habitats (bare sands, Z. noltii sea grass beds) during one year. The communities of the three habitats were characterised by low species richness, low abundance and biomass (when Hydrobia ulvae, 90% of abundance, is not considered) and high seasonal stability. The infaunal assemblages were particularly homogeneous between habitats without any characteristic species. Cordgrass eradication experiments were performed and zoobenthic recolonisation was observed the following year. Modifications in benthic fauna were observed on epifauna only. These results highlight the limited structuring effect of habitat heterogeneity at high tidal levels and in soft-bottom sediments where desiccation becomes the dominant factor determining infauna community structure.

  14. Habitat and host specificity of trematode metacercariae in fiddler crabs from mangrove habitats in Florida.

    Science.gov (United States)

    Smith, Nancy F; Ruiz, Gregory M; Reed, Sherry A

    2007-10-01

    Fiddler crabs (Uca spp.) are common inhabitants of temperate and tropical coastal communities throughout the world, often occupying specific microenvironments within mangrove and salt marsh habitats. As second intermediate hosts for trematodes, we investigated patterns of host distribution and parasitism for 3 species of sympatric fiddler crabs in mangrove habitats adjacent to the Indian River Lagoon, Florida. Fiddler crab distribution varied among species, with Uca speciosa dominating the low and mid intertidal regions of mangrove banks. This species also exhibited higher prevalence and abundance of Probolocoryphe lanceolata metacercariae compared with Uca rapax, which is relatively more abundant in the high intertidal zone. We conducted a field experiment to test whether U. speciosa was more heavily parasitized by P. lanceolata as a result of its habitat distribution by raising U. speciosa and U. rapax under identical environmental conditions. After exposure to shedding cercariae under the same field conditions, all individuals of U. speciosa became parasitized by P. lanceolata, whereas no U. rapax were parasitized, suggesting that differences in parasitism were driven by host selection. PMID:18163332

  15. Equilibrium bed-concentration of nonuniform sediment

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Knowledge of the equilibrium bed-concentration is vital to mathematical modeling of the river-bed deformation associated with suspended load but previous investigations only dealt with the reference concentration of uniform sediment because of difficulties in observation of the bed-concentration. This work is a first attempt to develop a theoretical formula for the equilibrium bed-concentration of any fraction of nonuniform sediment defined at the bed-surface. The formula is based on a stochastic-mechanistic model for the exchange of nonuniform sediment near the bed, and described as a function of incipient motion probability, non-ceasing probability, pick-up probability, and the ratio of the average single-step continuous motion time to static time. Comparison of bed-concentration calculated from the proposed formula with the measured data showed satisfactory agreement, indicating the present formula can be used for solving the differential equation governing the motion of suspended load.

  16. Bed bug aggregation pheromone finally identified.

    Science.gov (United States)

    Gries, Regine; Britton, Robert; Holmes, Michael; Zhai, Huimin; Draper, Jason; Gries, Gerhard

    2015-01-19

    Bed bugs have become a global epidemic and current detection tools are poorly suited for routine surveillance. Despite intense research on bed bug aggregation behavior and the aggregation pheromone, which could be used as a chemical lure, the complete composition of this pheromone has thus far proven elusive. Here, we report that the bed bug aggregation pheromone comprises five volatile components (dimethyl disulfide, dimethyl trisulfide, (E)-2-hexenal, (E)-2-octenal, 2-hexanone), which attract bed bugs to safe shelters, and one less-volatile component (histamine), which causes their arrestment upon contact. In infested premises, a blend of all six components is highly effective at luring bed bugs into traps. The trapping of juvenile and adult bed bugs, with or without recent blood meals, provides strong evidence that this unique pheromone bait could become an effective and inexpensive tool for bed bug detection and potentially their control. PMID:25529634

  17. Habitat Suitability Index Models: Red king crab

    Science.gov (United States)

    Jewett, Stephen C.; Onuf, Christopher P.

    1988-01-01

    A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for evaluating habitat of different life stages of red king crab (Paralithodes camtschatica). A model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) and 1.0 (optimum habitat) in Alaskan coastal waters, especially in the Gulf of Alaska and the southeastern Bering Sea. HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.

  18. Rhodolith beds are major CaCO3 bio-factories in the tropical South West Atlantic.

    Science.gov (United States)

    Amado-Filho, Gilberto M; Moura, Rodrigo L; Bastos, Alex C; Salgado, Leonardo T; Sumida, Paulo Y; Guth, Arthur Z; Francini-Filho, Ronaldo B; Pereira-Filho, Guilherme H; Abrantes, Douglas P; Brasileiro, Poliana S; Bahia, Ricardo G; Leal, Rachel N; Kaufman, Les; Kleypas, Joanie A; Farina, Marcos; Thompson, Fabiano L

    2012-01-01

    Rhodoliths are nodules of non-geniculate coralline algae that occur in shallow waters (Rhodolith beds stand with kelp beds, seagrass meadows, and coralline algal reefs as one of the world's four largest macrophyte-dominated benthic communities. Geographic distribution of rhodolith beds is discontinuous, with large concentrations off Japan, Australia and the Gulf of California, as well as in the Mediterranean, North Atlantic, eastern Caribbean and Brazil. Although there are major gaps in terms of seabed habitat mapping, the largest rhodolith beds are purported to occur off Brazil, where these communities are recorded across a wide latitudinal range (2°N-27°S). To quantify their extent, we carried out an inter-reefal seabed habitat survey on the Abrolhos Shelf (16°50'-19°45'S) off eastern Brazil, and confirmed the most expansive and contiguous rhodolith bed in the world, covering about 20,900 km(2). Distribution, extent, composition and structure of this bed were assessed with side scan sonar, remotely operated vehicles, and SCUBA. The mean rate of CaCO(3) production was estimated from in situ growth assays at 1.07 kg m(-2) yr(-1), with a total production rate of 0.025 Gt yr(-1), comparable to those of the world's largest biogenic CaCO(3) deposits. These gigantic rhodolith beds, of areal e