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Sample records for natal dispersing birds

  1. Scaling of Natal Dispersal Distances in Terrestrial Birds and Mammals

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    Glenn D. Sutherland

    2000-07-01

    Full Text Available Natal dispersal is a process that is critical in the spatial dynamics of populations, including population spread, recolonization, and gene flow. It is a central focus of conservation issues for many vertebrate species. Using data for 77 bird and 68 mammal species, we tested whether median and maximum natal dispersal distances were correlated with body mass, diet type, social system, taxonomic family, and migratory status. Body mass and diet type were found to predict both median and maximum natal dispersal distances in mammals: large species dispersed farther than small ones, and carnivorous species dispersed farther than herbivores and omnivores. Similar relationships occurred for carnivorous bird species, but not for herbivorous or omnivorous ones. Natal dispersal distances in birds or mammals were not significantly related to broad categories of social systems. Only in birds were factors such as taxonomic relatedness and migratory status correlated with natal dispersal, and then only for maximum distances. Summary properties of dispersal processes appeared to be derived from interactions among behavioral and morphological characteristics of species and from their linkages to the dynamics of resource availability in landscapes. In all the species we examined, most dispersers moved relatively short distances, and long-distance dispersal was uncommon. On the basis of these findings, we fit an empirical model based on the negative exponential distribution for calculating minimum probabilities that animals disperse particular distances from their natal areas. This model, coupled with knowledge of a species' body mass and diet type, can be used to conservatively predict dispersal distances for different species and examine possible consequences of large-scale habitat alterations on connectedness between populations. Taken together, our results can provide managers with the means to identify species vulnerable to landscape-level habitat changes

  2. Negative phenotypic and genetic correlation between natal dispersal propensity and nest-defence behaviour in a wild bird.

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    Bize, Pierre; Daniel, Grégory; Viblanc, Vincent A; Martin, Julien G A; Doligez, Blandine

    2017-07-01

    Natural selection is expected to favour the integration of dispersal and phenotypic traits allowing individuals to reduce dispersal costs. Accordingly, associations have been found between dispersal and personality traits such as aggressiveness and exploration, which may facilitate settlement in a novel environment. However, the determinism of these associations has only rarely been explored. Here, we highlight the functional integration of individual personality in nest-defence behaviour and natal dispersal propensity in a long-lived colonial bird, the Alpine swift ( Apus melba ), providing insights into genetic constraints shaping the coevolution of these two traits. We report a negative association between natal dispersal and nest-defence (i.e. risk taking) behaviour at both the phenotypic and genetic level. This negative association may result from direct selection if risk-averseness benefits natal dispersers by reducing the costs of settlement in an unfamiliar environment, or from indirect selection if individuals with lower levels of nest defence also show lower levels of aggressiveness, reducing costs of settlement among unfamiliar neighbours in a colony. In both cases, these results highlight that risk taking is an important behavioural trait to consider in the study of dispersal evolution. © 2017 The Author(s).

  3. BREEDING AND NATAL DISPERSAL IN THE PUERTO RICAN VIREO

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    BETHANY L. WOODWORTH; JOHN FAABORG; WAYNE J. ARENDT

    1998-01-01

    Information on dispersali s critical for understandingt he population dynamicso f birds. We estimated breeding and natal dispersal in two studies of a population of the Puerto Rican Vireo (Vireo latimeri) that is in danger of local extirpation due to low reproductive success from 7.1-29% of adult males and 12.5 - 25% of adult females changed territories between...

  4. Natal dispersal and personalities in great tits (Parus major)

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    Dingemanse, NJ; Both, C; van Noordwijk, AJ; Rutten, AL; Drent, PJ; Noordwijk, Arie J. van; Drent, Piet J.

    2003-01-01

    Dispersal is a major determinant of the dynamics and genetic structure of populations, and its consequences depend not only on average dispersal rates and distances, but also on the characteristics of dispersing and philopatric individuals. We investigated whether natal dispersal correlated with a

  5. Natal Dispersal in the North Island Robin (Petroica longipes: the Importance of Connectivity in Fragmented Habitats

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    Askia K. Wittern

    2007-12-01

    Full Text Available Natal dispersal is an important component in bird population dynamics and can influence the persistence of local and metapopulations. We examined natal dispersal in the North Island robin (Petroica longipes, a sedentary bird species distributed in a fragmented forest habitat on Tiritiri Matangi Island, New Zealand. Earlier studies have shown that the only dispersal phase in this species takes place when juveniles leave their natal patch, and that juveniles who fail to find suitable habitat do not survive their first winter. These findings suggest that natal dispersal behavior in this species is important for population viability. We found that juveniles were highly affected by the fragmentation of the forest habitat, with patch occupancy being positively correlated with degree of connectivity of the landscape. Most juvenile movements (52.1% were observed between patches that were separated by less than 20 m. Juvenile North Island robins were found in all forest habitat types, including young and open stands. This suggests that the juveniles are not dependent on old forest stands during their dispersal phase. Based on these findings, we suggest that management of this regionally-threatened species should focus not only on maintaining populations in occupied patches and increasing the habitat quality of these patches, but also on protecting existing forest patches acting as corridors and creating new forest habitat among patches. This would greatly increase the viability of the species' metapopulations by increasing dispersal success between both unoccupied patches and subpopulations. Additionally, increased connectivity between forest patches could also be expected to increase the probability of successful dispersal of other threatened native species, many of which are also sensitive to the high degree of fragmentation of their habitats.

  6. Recovery distances of nestling Bald Eagles banded in Florida and implications for natal dispersal and philopatry

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    Wood, Petra Bohall

    2009-01-01

    I used band recovery data to examine distances between banding and recovery locations for 154 nestling Florida Bald Eagles and discuss the implications for understanding natal dispersal and philopatry in this species. Band recoveries occurred in 23 U.S. states and five Canadian provinces between 1931–2005. Recovery distance from the natal nest averaged longer for the youngest age classes (ANOVA: F  =  3.59; df  =  5, 153; P  =  0.005), for individuals banded in earlier decades (F  =  1.94; df  =  5, 153; P  =  0.093), and for the months of May through October (F  =  3.10; df  =  12, 153;P < 0.001). Of 35 individuals classed as mature (≥3.9 yr old when recovered; range 3.9–36.5 yr), 31 were located within Florida, which suggested a strong degree of philopatry to the natal state. Among 21 mature eagles of known sex with known banding and recovery locations in Florida, females, particularly younger birds, had longer recovery distances (N  =  9, mean  =  93 km, SE  =  22.4) than did males (N  =  12, mean  =  31 km, SE  =  5.3; t  =  2.67, df  =  19, P  =  0.026). The records examined here suggest a high degree of philopatry and relatively short natal dispersal distances, particularly in male Bald Eagles.

  7. Fluff-thieving birds sabotage seed dispersal

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    Rohwer, Vanya G.; Pauw, Anton; Martin, Paul R.

    2017-01-01

    Characterizing many species interactions as mutualisms can be misleading because some members of the interaction derive greater fitness benefits at the expense of other members. We provide detailed natural history data on a suspected bird?plant mutualism in South Africa where many species of birds use fluffy Eriocephalus seed material to construct their nests, potentially dispersing seeds for the plant. We focus on a common bird, Prinia maculosa, which invests heavily in gathering Eriocephalu...

  8. Estimating natal dispersal movement rates of female European ducks with multistate modeling

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    Blums, P.; Nichols, J.D.; Hines, J.E.; Lindberg, M.S.; Mednis, A.

    2003-01-01

    1. We used up to 34 years of capture-recapture data from about 22,100 new releases of day-old female ducklings and multistate modelling to test predictions about the influence of environmental, habitat and management factors on natal dispersal probability of three species of ducks within the Engure Marsh, Latvia. 2. The mean natal dispersal distances were very similar (c . 0?6-0?7 km) for all three species and were on average 2?7 times greater than breeding dispersal distances recorded within the same study system. 3. We were unable to confirm the kinship hypothesis and found no evidence that young first-nesting females nested closer to their relatives (either mother or sister) than to the natal nest. 4. Young female northern shovelers, like adults, moved from small islands to the large island when water level was high and vice versa when water level was low before the construction of elevated small islands. Movement probabilities between the two strata were much higher for young shovelers than adults, suggesting that young birds had not yet developed strong fidelity to the natal site. Movements of young female tufted ducks, unlike those of shovelers, were not dependent on water level fluctuations and reflected substantial flexibility in choice of first nesting sites. 5. Data for young birds supported our earlier conclusion that common pochard nesting habitats in black-headed gull colonies were saturated during the entire study period. Young females, like the two adult age groups, moved into and out of colonies with similar probability. Fidelity probability of female pochards to each stratum increased with age, being the lowest (0?62) for young (DK) females, intermediate (0?78) for yearlings (SY) and the highest (0?84) for adult (ASY) females. 6. Young female tufted ducks, like adults, showed higher probabilities of moving from islands to emergent marshes when water levels were higher both before and after habitat management. The relationship between the spring

  9. Overseas seed dispersal by migratory birds.

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    Viana, Duarte S; Gangoso, Laura; Bouten, Willem; Figuerola, Jordi

    2016-01-13

    Long-distance dispersal (LDD) promotes the colonization of isolated and remote habitats, and thus it has been proposed as a mechanism for explaining the distributions of many species. Birds are key LDD vectors for many sessile organisms such as plants, yet LDD beyond local and regional scales has never been directly observed nor quantified. By sampling birds caught while in migratory flight by GPS-tracked wild falcons, we show that migratory birds transport seeds over hundreds of kilometres and mediate dispersal from mainland to oceanic islands. Up to 1.2% of birds that reached a small island of the Canary Archipelago (Alegranza) during their migration from Europe to Sub-Saharan Africa carried seeds in their guts. The billions of birds making seasonal migrations each year may then transport millions of seeds. None of the plant species transported by the birds occurs in Alegranza and most do not occur on nearby Canary Islands, providing a direct example of the importance of environmental filters in hampering successful colonization by immigrant species. The constant propagule pressure generated by these LDD events might, nevertheless, explain the colonization of some islands. Hence, migratory birds can mediate rapid range expansion or shifts of many plant taxa and determine their distribution. © 2016 The Author(s).

  10. Overseas seed dispersal by migratory birds

    NARCIS (Netherlands)

    Viana, D.S.; Gangoso, L.; Bouten, W.; Figuerola, J.

    2016-01-01

    Long-distance dispersal (LDD) promotes the colonization of isolated and remote habitats, and thus it has been proposed as a mechanism for explaining the distributions of many species. Birds are key LDD vectors for many sessile organisms such as plants, yet LDD beyond local and regional scales has

  11. Fluff-thieving birds sabotage seed dispersal.

    Science.gov (United States)

    Rohwer, Vanya G; Pauw, Anton; Martin, Paul R

    2017-01-01

    Characterizing many species interactions as mutualisms can be misleading because some members of the interaction derive greater fitness benefits at the expense of other members. We provide detailed natural history data on a suspected bird-plant mutualism in South Africa where many species of birds use fluffy Eriocephalus seed material to construct their nests, potentially dispersing seeds for the plant. We focus on a common bird, Prinia maculosa , which invests heavily in gathering Eriocephalus material. Prinias spent 5 of their median 6-day nest construction period adding seed material to their nests and frequently travelled outside their territory boundary to gather Eriocephalus material. Yet, prinias gathered primarily Eriocephalus fluff and actively avoided gathering seeds. The average prinia nest contained only 6.6 seeds, but contained fluff from 579 seeds. These data suggest that prinias provide limited dispersal benefits to Eriocephalus plants. By contrast, the large amounts of Eriocephalus fluff in prinia nests, and the effort that prinias invest in gathering it, suggest that prinias benefit from constructing their nests with Eriocephalus material. We end by outlining hypotheses for possible fitness benefits that Eriocephalus material could provide prinias and other birds.

  12. Fluff-thieving birds sabotage seed dispersal

    Science.gov (United States)

    2017-01-01

    Characterizing many species interactions as mutualisms can be misleading because some members of the interaction derive greater fitness benefits at the expense of other members. We provide detailed natural history data on a suspected bird–plant mutualism in South Africa where many species of birds use fluffy Eriocephalus seed material to construct their nests, potentially dispersing seeds for the plant. We focus on a common bird, Prinia maculosa, which invests heavily in gathering Eriocephalus material. Prinias spent 5 of their median 6-day nest construction period adding seed material to their nests and frequently travelled outside their territory boundary to gather Eriocephalus material. Yet, prinias gathered primarily Eriocephalus fluff and actively avoided gathering seeds. The average prinia nest contained only 6.6 seeds, but contained fluff from 579 seeds. These data suggest that prinias provide limited dispersal benefits to Eriocephalus plants. By contrast, the large amounts of Eriocephalus fluff in prinia nests, and the effort that prinias invest in gathering it, suggest that prinias benefit from constructing their nests with Eriocephalus material. We end by outlining hypotheses for possible fitness benefits that Eriocephalus material could provide prinias and other birds. PMID:28280552

  13. Natal dispersal patterns are not associated with inbreeding avoidance in the Seychelles Warbler

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    Eikenaar, C.; Komdeur, J.; Richardson, D. S.

    In this study, we test whether patterns of territory inheritance, social mate choice and female-biased natal dispersal act as inbreeding avoidance mechanisms in the cooperatively breeding Seychelles warbler. Our results show that Seychelles warblers do not reduce the likelihood of inbreeding by

  14. Population genetic structure and long-distance dispersal of a recently expanding migratory bird.

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    Ramos, Raül; Song, Gang; Navarro, Joan; Zhang, Ruiying; Symes, Craig T; Forero, Manuela G; Lei, Fumin

    2016-06-01

    Long-distance dispersal events and their derivable increases of genetic diversity have been highlighted as important ecological and evolutionary determinants that improve performances of range-expanding species. In the context of global environmental change, specific dispersal strategies have to be understood and foreseen if we like to prevent general biodiversity impoverishment or the spread of allochthonous diseases. We explored the genetic structure and potential population mixing on the recently range-expanding European bee-eater Merops apiaster. In addition, the species is suspected of harbouring and disseminating the most relevant disease for bees and apiculture, Nosema microsporidia. In agreement with complementary ringing recovery data and morphometric measurements, genetic results on two mitochondrial genes and 12 microsatellites showed a reasonably well-structured population partitioning along its breeding distribution. Microsatellite results indicated that not only did a few birds recently disperse long distance during their return migrations and change their natal breeding areas, but also that a group of allochthonous birds together founded a new colony. Although we did not provide evidence on the direct implication of birds in the widespread of Nosema parasites, our finding on the long-distance dispersal of bird flocks between remote breeding colonies adds concern about the role of European bee-eaters in the spread of such disease at a large, inter-continental scale. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Extended phenotype: nematodes turn ants into bird-dispersed fruits

    DEFF Research Database (Denmark)

    Hughes, D P; Kronauer, D J C; Boomsma, J J

    2008-01-01

    A recent study has discovered a novel extended phenotype of a nematode which alters its ant host to resemble ripe fruit. The infected ants are in turn eaten by frugivorous birds that disperse the nematode's eggs.......A recent study has discovered a novel extended phenotype of a nematode which alters its ant host to resemble ripe fruit. The infected ants are in turn eaten by frugivorous birds that disperse the nematode's eggs....

  16. Were Malagasy Uncarina fruits dispersed by the extinct elephant bird?

    Directory of Open Access Journals (Sweden)

    N. Illing

    2010-02-01

    Full Text Available We hypothesise that the spiny fruits of the endemic Madagascar
    genus Uncarina (Pedaliaceae are trample burrs that evolved to be
    dispersed on the feet of the extinct elephant bird (Aepyornis. Our
    evidence is: i the morphology of the fruit with its large grapple
    hooks is more likely to attach to a foot than to adhere to fur and
    ii the presentation of mature fruits on the ground rather than in the
    canopy. These differences to adhesive burrs make lemurs unlikely
    dispersers. We argue, given the absence of other large terrestrial
    mammals in Madagascar, that the most likely dispersers of
    Uncarina fruits were the extinct large birds. If correct, our hypothesis
    has implications for conservation of Uncarina, the biogeography
    of the elephant birds and dispersal biology. For
    example, we predict that the demography of Uncarina will be
    skewed towards adult plants, and that the dispersal mutualism
    could possibly be rescued by domestic animals.

  17. Breeding Dispersal by Birds in a Dynamic Urban Ecosystem.

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    Marzluff, John M; DeLap, Jack H; Oleyar, M David; Whittaker, Kara A; Gardner, Beth

    2016-01-01

    Changes in land cover during urbanization profoundly affect the diversity of bird communities, but the demographic mechanisms affecting diversity are poorly known. We advance such understanding by documenting how urbanization influences breeding dispersal-the annual movement of territorial adults-of six songbird species in the Seattle, WA, USA metropolitan area. We color-banded adults and mapped the centers of their annual breeding activities from 2000-2010 to obtain 504 consecutive movements by 337 adults. By comparing movements, annual reproduction, and mate fidelity among 10 developed, 5 reserved, and 11 changing (areas cleared and developed during our study) landscapes, we determined that adaptive breeding dispersal of sensitive forest species (Swainson's Thrush and Pacific wren), which involves shifting territory and mate after reproductive failure, was constrained by development. In changing lands, sensitive forest specialists dispersed from active development to nearby forested areas, but in so doing suffered low annual reproduction. Species tolerant of suburban lands (song sparrow, spotted towhee, dark-eyed junco, and Bewick's wren) dispersed adaptively in changing landscapes. Site fidelity ranged from 0% (Pacific wren in changing landscape) to 83% (Bewick's wren in forest reserve). Mate fidelity ranged from 25% (dark-eyed junco) to 100% (Bewick's wren). Variation in fidelity to mate and territory was consistent with theories positing an influence of territory quality, asynchronous return from migration, prior productivity, and reproductive benefits of retaining a familiar territory. Costly breeding dispersal, as well as reduced reproductive success and lowered survival cause some birds to decline in the face of urbanization. In contrast, the ability of species that utilize edges and early successional habitats to breed successfully, disperse to improve reproductive success after failure, and survive throughout the urban ecosystem enables them to maintain

  18. Breeding Dispersal by Birds in a Dynamic Urban Ecosystem.

    Directory of Open Access Journals (Sweden)

    John M Marzluff

    Full Text Available Changes in land cover during urbanization profoundly affect the diversity of bird communities, but the demographic mechanisms affecting diversity are poorly known. We advance such understanding by documenting how urbanization influences breeding dispersal-the annual movement of territorial adults-of six songbird species in the Seattle, WA, USA metropolitan area. We color-banded adults and mapped the centers of their annual breeding activities from 2000-2010 to obtain 504 consecutive movements by 337 adults. By comparing movements, annual reproduction, and mate fidelity among 10 developed, 5 reserved, and 11 changing (areas cleared and developed during our study landscapes, we determined that adaptive breeding dispersal of sensitive forest species (Swainson's Thrush and Pacific wren, which involves shifting territory and mate after reproductive failure, was constrained by development. In changing lands, sensitive forest specialists dispersed from active development to nearby forested areas, but in so doing suffered low annual reproduction. Species tolerant of suburban lands (song sparrow, spotted towhee, dark-eyed junco, and Bewick's wren dispersed adaptively in changing landscapes. Site fidelity ranged from 0% (Pacific wren in changing landscape to 83% (Bewick's wren in forest reserve. Mate fidelity ranged from 25% (dark-eyed junco to 100% (Bewick's wren. Variation in fidelity to mate and territory was consistent with theories positing an influence of territory quality, asynchronous return from migration, prior productivity, and reproductive benefits of retaining a familiar territory. Costly breeding dispersal, as well as reduced reproductive success and lowered survival cause some birds to decline in the face of urbanization. In contrast, the ability of species that utilize edges and early successional habitats to breed successfully, disperse to improve reproductive success after failure, and survive throughout the urban ecosystem enables them

  19. Vagrant western red-shouldered hawks: origins, natal dispersal patterns, and survival

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    Bloom, Peter H.; Scott, J. Michael; Papp, Joseph M.; Thomas, Scott E.; Kidd, Jeff W.

    2011-01-01

    We report the results of a 40-year study of the western Red-shouldered Hawk (Buteo lineatus elegans) involving the banding of 2742 nestlings in southern California from 1970 to 2009 (this study) plus 127 nestlings banded in other California studies (1956–2008) and the analyses of 119 records of subsequent recovery from the Bird Banding Laboratory (1957–2009). Of the Red-shouldered Hawks recovered, 109 (91.6%) moved 100 km (long-distance dispersers). Three (2.5%), all long-distance dispersers, were vagrants (recovered outside the species' range of residency), and were found 374 to 843 km northeast and south of their banding locations in the Mojave, Great Basin, and Vizcaino deserts. The distribution of directions of short-distance dispersal was bipolar, closely corresponding with the northwest—southeast orientation of the species' range in southern California, while that of long-distance dispersers was mainly to the north. One of 10 long-distance dispersers, a nonvagrant, survived well into the age of breeding (103.0 months), whereas eight of the other nine perished before 14.5 months. The implications of vagrancy for conservation of this resident subspecies are that a relatively small source area can contribute genetic material over a vastly larger receiving area but rarely does so because of high mortality rates. Nonetheless, the movements of vagrants we documented provide evidence for the species' potential to populate new landscapes in response to changing environmental conditions and to maintain genetic heterogeneity within existing populations.

  20. On the estimation of dispersal and movement of birds

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    Kendall, W.L.; Nichols, J.D.

    2004-01-01

    The estimation of dispersal and movement is important to evolutionary and population ecologists, as well as to wildlife managers. We review statistical methodology available to estimate movement probabilities. We begin with cases where individual birds can be marked and their movements estimated with the use of multisite capture-recapture methods. Movements can be monitored either directly, using telemetry, or by accounting for detection probability when conventional marks are used. When one or more sites are unobservable, telemetry, band recoveries, incidental observations, a closed- or open-population robust design, or partial determinism in movements can be used to estimate movement. When individuals cannot be marked, presence-absence data can be used to model changes in occupancy over time, providing indirect inferences about movement. Where abundance estimates over time are available for multiple sites, potential coupling of their dynamics can be investigated using linear cross-correlation or nonlinear dynamic tools.

  1. Neither philopatric nor panmictic: microsatellite and mtDNA evidence suggests lack of natal homing but limits to dispersal in Pacific lamprey.

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    Spice, Erin K; Goodman, Damon H; Reid, Stewart B; Docker, Margaret F

    2012-06-01

    Most species with lengthy migrations display some degree of natal homing; some (e.g. migratory birds and anadromous salmonids) show spectacular feats of homing. However, studies of the sea lamprey (Petromyzon marinus) indicate that this anadromous species locates spawning habitat based on pheromonal cues from larvae rather than through philopatry. Previous genetic studies in the anadromous Pacific lamprey (Entosphenus tridentatus) have both supported and rejected the hypothesis of natal homing. To resolve this, we used nine microsatellite loci to examine the population structure in 965 Pacific lamprey from 20 locations from central British Columbia to southern California and supplemented this analysis with mitochondrial DNA restriction fragment length polymorphism analysis on a subset of 530 lamprey. Microsatellite analysis revealed (i) relatively low but often statistically significant genetic differentiation among locations (97% pairwise F(ST) values were <0.04 but 73.7% were significant); and (ii) weak but significant isolation by distance (r(2) = 0.0565, P = 0.0450) but no geographic clustering of samples. The few moderate F(ST) values involved comparisons with sites that were geographically distant or far upstream. The mtDNA analysis--although providing less resolution among sites (only 4.7%F(ST) values were significant)--was broadly consistent with the microsatellite results: (i) the southernmost site and some sites tributary to the Salish Sea were genetically distinct; and (ii) southern sites showed higher haplotype and private haplotype richness. These results are inconsistent with philopatry, suggesting that anadromous lampreys are unusual among species with long migrations, but suggest that limited dispersal at sea precludes panmixia in this species. © 2012 Blackwell Publishing Ltd.

  2. Application of large-scale parentage analysis for investigating natal dispersal in highly vagile vertebrates: a case study of American black bears (Ursus americanus).

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    Moore, Jennifer A; Draheim, Hope M; Etter, Dwayne; Winterstein, Scott; Scribner, Kim T

    2014-01-01

    Understanding the factors that affect dispersal is a fundamental question in ecology and conservation biology, particularly as populations are faced with increasing anthropogenic impacts. Here we collected georeferenced genetic samples (n = 2,540) from three generations of black bears (Ursus americanus) harvested in a large (47,739 km2), geographically isolated population and used parentage analysis to identify mother-offspring dyads (n = 337). We quantified the effects of sex, age, habitat type and suitability, and local harvest density at the natal and settlement sites on the probability of natal dispersal, and on dispersal distances. Dispersal was male-biased (76% of males dispersed) but a small proportion (21%) of females also dispersed, and female dispersal distances (mean ± SE  =  48.9±7.7 km) were comparable to male dispersal distances (59.0±3.2 km). Dispersal probabilities and dispersal distances were greatest for bears in areas with high habitat suitability and low harvest density. The inverse relationship between dispersal and harvest density in black bears suggests that 1) intensive harvest promotes restricted dispersal, or 2) high black bear population density decreases the propensity to disperse. Multigenerational genetic data collected over large landscape scales can be a powerful means of characterizing dispersal patterns and causal associations with demographic and landscape features in wild populations of elusive and wide-ranging species.

  3. Application of large-scale parentage analysis for investigating natal dispersal in highly vagile vertebrates: a case study of American black bears (Ursus americanus.

    Directory of Open Access Journals (Sweden)

    Jennifer A Moore

    Full Text Available Understanding the factors that affect dispersal is a fundamental question in ecology and conservation biology, particularly as populations are faced with increasing anthropogenic impacts. Here we collected georeferenced genetic samples (n = 2,540 from three generations of black bears (Ursus americanus harvested in a large (47,739 km2, geographically isolated population and used parentage analysis to identify mother-offspring dyads (n = 337. We quantified the effects of sex, age, habitat type and suitability, and local harvest density at the natal and settlement sites on the probability of natal dispersal, and on dispersal distances. Dispersal was male-biased (76% of males dispersed but a small proportion (21% of females also dispersed, and female dispersal distances (mean ± SE  =  48.9±7.7 km were comparable to male dispersal distances (59.0±3.2 km. Dispersal probabilities and dispersal distances were greatest for bears in areas with high habitat suitability and low harvest density. The inverse relationship between dispersal and harvest density in black bears suggests that 1 intensive harvest promotes restricted dispersal, or 2 high black bear population density decreases the propensity to disperse. Multigenerational genetic data collected over large landscape scales can be a powerful means of characterizing dispersal patterns and causal associations with demographic and landscape features in wild populations of elusive and wide-ranging species.

  4. Social Mating System and Sex-Biased Dispersal in Mammals and Birds: A Phylogenetic Analysis

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    Mabry, Karen E.; Shelley, Erin L.; Davis, Katie E.; Blumstein, Daniel T.; Van Vuren, Dirk H.

    2013-01-01

    The hypothesis that patterns of sex-biased dispersal are related to social mating system in mammals and birds has gained widespread acceptance over the past 30 years. However, two major complications have obscured the relationship between these two behaviors: 1) dispersal frequency and dispersal distance, which measure different aspects of the dispersal process, have often been confounded, and 2) the relationship between mating system and sex-biased dispersal in these vertebrate groups has not been examined using modern phylogenetic comparative methods. Here, we present a phylogenetic analysis of the relationship between mating system and sex-biased dispersal in mammals and birds. Results indicate that the evolution of female-biased dispersal in mammals may be more likely on monogamous branches of the phylogeny, and that females may disperse farther than males in socially monogamous mammalian species. However, we found no support for a relationship between social mating system and sex-biased dispersal in birds when the effects of phylogeny are taken into consideration. We caution that although there are larger-scale behavioral differences in mating system and sex-biased dispersal between mammals and birds, mating system and sex-biased dispersal are far from perfectly associated within these taxa. PMID:23483957

  5. Dispersal of invasive Phytolacca americana seeds by birds in an urban garden in China.

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    Li, Ning; Yang, Wen; Fang, Shubo; Li, Xinhai; Liu, Zhanchen; Leng, Xin; An, Shuqing

    2017-01-01

    Although seed dispersal is a key process determining the regeneration and spread of invasive plant populations, few studies have explicitly addressed the link between dispersal vector behavior and seedling recruitment to gain insight into the invasion process within an urban garden context. We evaluated the role of bird vectors in the dispersal of pokeweed (Phytolacca americana), a North American herb that is invasive in urban gardens in China. Fruiting P. americana attracted both generalist and specialist bird species that fed on and dispersed its seeds. The generalist species Pycnonotus sinensis and Urocissa erythrorhyncha were the most frequent dispersers. Seedling numbers of P. americana were strongly associated with the perching behavior of frugivorous birds. If newly recruited bird species use seedling-safe perching sites, the P. americana will regenerate faster, which would enhance its invasive potential. Based on our observations, we conclude that the 2 main bird vectors, P. sinensis and U. erythrorhyncha, provide potential effective dispersal agents for P. americana. Our results highlight the role of native birds in seed dispersal of invasive plants in urban gardens. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  6. Sex-biased natal dispersal and inbreeding avoidance in American black bears as revealed by spatial genetic analyses.

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    Costello, Cecily M; Creel, Scott R; Kalinowski, Steven T; Vu, Ninh V; Quigley, Howard B

    2008-11-01

    We tested the hypothesis that sex-biased natal dispersal reduces close inbreeding in American black bears, a solitary species that exhibits nearly complete male dispersal and female philopatry. Using microsatellite DNA and spatial data from reproductively mature bears (>or= 4 years old), we examined the spatial genetic structure of two distinct populations in New Mexico from 1993 to 2000. As predicted, relatedness (r) and the frequency of close relationships (parent-offspring or full siblings) decreased with distance among female dyads, but little change was observed among male or opposite-sex dyads. Neighbouring females were more closely related than neighbouring males. The potential for inbreeding was low. Most opposite-sex pairs that lived sufficiently close to facilitate mating were unrelated, and few were close relatives. We found no evidence that bears actively avoided inbreeding in their selection of mates from this nearby pool, as mean r and relationship frequencies did not differ between potential and actual mating pairs (determined by parentage analysis). These basic patterns were apparent in both study areas despite a nearly two-fold difference in density. However, the sex bias in dispersal was less pronounced in the lower-density area, based on proportions of bears with male and female relatives residing nearby. This result suggests that male bears may respond to reduced competition by decreasing their rate or distance of dispersal. Evidence supports the hypothesis that inbreeding avoidance is achieved by means of male-biased dispersal but also indicates that competition (for mates or resources) modifies dispersal patterns.

  7. Global dynamics of dispersal and diversification among passerine birds

    DEFF Research Database (Denmark)

    Kennedy, Jonathan David

    2017-01-01

    , and the capacity of different geographic areas to preserve taxa through time. Here, I assess the relationships among these processes, to elucidate the causes of geographic and taxonomic variation in species richness among the most speciose order of birds: the Passeriformes (c. 6,500 species). To achieve this, I...

  8. Quantity component of the effectiveness of seed dispersal by birds in the temperate rainforest of Chiloé, Chile

    OpenAIRE

    Salvande, Miguel; Figueroa, Javier A; Armesto, Juan J

    2011-01-01

    The quantity component of the disperser effectiveness of resident birds during the autumn-winter period has not yet been detailed in temperate rainforests of South America. In this study, the potentially frugivorous bird species in the temperate rainforests of southern Chile during the Austral autumn-winter were identified, and the quantity component of the disperser effectiveness of the birds (number of visits and number of seeds dispersed per hour) were evaluated for the tree species Luma a...

  9. The ties that bind: Maternal kin bias in a multilevel primate society despite natal dispersal by both sexes.

    Science.gov (United States)

    Städele, Veronika; Pines, Mathew; Swedell, Larissa; Vigilant, Linda

    2016-07-01

    In many social animals, individuals derive fitness benefits from close social bonds, which are often formed among kin of the philopatric sex. Hamadryas baboons, however, exhibit a hierarchical, multilevel social system where both sexes disperse from their natal one-male-unit (OMU). Although this would seem to hinder maintenance of kin ties, both sexes appear largely philopatric at the higher order band and clan levels, possibly allowing for bonds with same sex kin by both males and females. In order to investigate the possibility of kin bonds in hamadryas baboons, we identified kin dyads in a band without known pedigree information using a large panel of genetic markers: 1 Y-linked, 4 X-linked, and 23 autosomal microsatellites and part of the mitochondrial hypervariable region I. With these data, we performed a kinship analysis while accounting for misclassification rates through simulations and determined kinship among two types of dyads: leader and follower males and female dyads within OMUs. Leader and follower males were maternal relatives more often than expected by chance, suggesting that kinship plays a role in the formation of these relationships. Moreover, maternal female relatives were found in the same OMU more often than expected by chance, indicating that females may be motivated to maintain post-dispersal contact with maternal female kin. Our results suggest that hamadryas baboons can recognize maternal kin and that kin selection has contributed to shaping their complex social system. This implies that an ancestral maternal kin bias has been retained in hamadryas society. Am. J. Primatol. 78:731-744, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  10. Frugivory and seed dispersal by birds in Cereus jamacaru DC. ssp. jamacaru (Cactaceae) in the Caatinga of Northeastern Brazil.

    Science.gov (United States)

    Gomes, V G N; Quirino, Z G M; Araujo, H F P

    2014-02-01

    Studies of the dispersal modes of plants aid our understanding of the dynamics of resource and its availability for dispersal agents. The present work sought to characterize the fruiting patterns of the native Caatinga (dryland) cactus Cereus jamacaru, identify its principal dispersers, and evaluate the effects of seed passage through digestive tract of dispersers on its germination. Cereus jamacaru present an annual fruiting pattern and fruiting peaks occurred during June/2009 and February/2010. A total of 135 visits by nine species of resident Caatinga bird species were recorded. The most frequent visiting bird species were Paroaria dominicana and Euphonia chlorotica. Length of bird visits varied from 15 seconds to 4 minutes and seeds removed by birds travelled 10.6 ± 11.2 m until dispersers make the first landing perch, in some cases more than 40 meters away. Germination tests show birds had a high quantity of viable seeds of C. jamacaru in its feces. Seeds that passed through the digestive tract of birds showed a similar germinability of the seeds of the control group. However, the seeds dispersed by birds showed lowest mean germination time related to the control group seeds. This study highlights the potential role of birds as seed dispersers of C. jamacaru, swallowing the whole seeds and defecating intact seeds, accelerating the germination process and transporting seeds away from the mother plant.

  11. Can salvage logging affect seed dispersal by birds into burned forests?

    Science.gov (United States)

    Rost, J.; Pons, P.; Bas, J. M.

    2009-09-01

    The recovery of vegetation in Mediterranean ecosystems after wildfire is mostly a result of direct regeneration, since the same species existing before the fire regenerate on-site by seeding or resprouting. However, the possibility of plant colonization by dispersal of seeds from unburned areas remains poorly studied. We addressed the role of the frugivorous, bird-dependent seed dispersal (seed rain) of fleshy-fruited plants in a burned and managed forest in the second winter after a fire, before on-site fruit production had begun. We also assessed the effect on seed rain of different microhabitats resulting from salvage logging (erosion barriers, standing snags, open areas), as well as the microhabitats of unlogged patches and an unburned control forest, taking account of the importance of perches as seed rain sites. We found considerable seed rain by birds in the burned area. Seeds, mostly from Olive trees Olea europaea and Evergreen pistaches Pistacia lentiscus, belonged to plants fruiting only in surrounding unburned areas. Seed rain was heterogeneous, and depended on microhabitat, with the highest seed density in the unburned control forest but closely followed by the wood piles of erosion barriers. In contrast, very low densities were found under perches of standing snags. Furthermore, frugivorous bird richness seemed to be higher in the erosion barriers than elsewhere. Our results highlight the importance of this specific post-fire management in bird-dependent seed rain and also may suggest a consequent heterogeneous distribution of fleshy-fruited plants in burned and managed areas. However, there needs to be more study of the establishment success of dispersed seeds before an accurate assessment can be made of the role of bird-mediated seed dispersal in post-fire regeneration.

  12. Partitioning of seed dispersal services between birds and bats in a fragment of the Brazilian Atlantic Forest

    Directory of Open Access Journals (Sweden)

    Raissa Sarmento

    2014-06-01

    Full Text Available Community-level network studies suggest that seed dispersal networks may share some universal properties with other complex systems. However, most of the datasets used so far in those studies have been strongly biased towards temperate birds, including not only dispersers, but also seed predators. Recent evidence from multi-taxon networks suggests that seed dispersal networks are not all alike and may be more complex than previously thought. Here, we used network theory to evaluate seed dispersal in a strongly impacted Atlantic Forest fragment in northeastern Brazil, where bats and birds are the only extant dispersers. We hypothesized that the seed dispersal network should be more modular then nested, and that the dispersers should segregate their services according to dispersal syndromes. Furthermore, we predicted that bat and bird species that are more specialized in frugivory would be more important for maintaining the network structure. The mixed network contained 56 plant species, 12 bat species, and eight bird species, and its structure was more modular (M = 0.58 then nested (NODF = 0.21 compared with another multi-taxon network and 21 single-taxon networks (with either bats or birds. All dispersed fruits had seeds smaller than 9 mm. Bats dispersed mainly green fruits, whereas birds dispersed fruits of various colors. The network contained eight modules: five with birds only, two with bats only, and one mixed. Most dispersers were peripheral, and only specialized frugivores acted as hubs or connectors. Our results strongly support recent studies, suggesting that seed dispersal networks are complex mosaics, where different taxa form separate modules with different properties, which in turn play complementary roles in the maintenance of the associated ecosystem functions and services.

  13. Bird attributes, plant characteristics, and seed dispersal of Pera glabrata (Schott, 1858), (Euphorbiaceae) in a disturbed cerrado area.

    Science.gov (United States)

    Francisco, M R; Lunardi, V O; Galetti, M

    2007-11-01

    Several plant characteristics, such as fruit production, nutrient reward, secondary compounds, and fruit color display, affect fruit choice by birds. On the other hand, several bird attributes affect their efficiency as dispersers. Here we investigate the ornithochoric seed dispersal of Pera glabrata Schott (Euphorbiaceae) in a cerrado fragment in southeastern Brazil. A set of bird attributes, such as frequency of visits, number of diaspores eaten, time spent foraging, methods of taking and handling the diaspores and agonistic interactions were analyzed in order to infer about the potential of each species to act as a seed disperser. Birds were the unique seed dispersers of these oil-rich diaspores. We observed 414 bird visits during 60 hours of focal observations in five trees from December 1999 to January 2000. Twenty bird species from seven families ate the diaspores of P. glabrata, but only 14 species were considered potential seed dispersers because they swallowed the diaspores, increasing the probabilities for the seeds to be defecated and/or regurgitated away from the parent trees. The main potential seed dispersers were: Turdus leucomelas (Muscicapidae), Dacnis cayana (Emberizidae), Colaptes melanochloros (Picidae) and Elaenia spp. (Tyrannidae). We did not find any significant seasonal change in the number of visits on the fruiting trees throughout the day. We also did not find any relation between the number of visits per tree and fruit production. The most effective seed dispersers of P. glabrata were generalist birds, which have a high visiting rate, high fruit consumption rate, and spend short periods on the plants. The large number of species recorded as potential seed dispersers of P. glabrata, being most of them very abundant even in Brazilian disturbed areas, may guarantee seed dispersal of this plant in small fragments and regenerating areas.

  14. Extreme genetic structure in a social bird species despite high dispersal capacity.

    Science.gov (United States)

    Morinha, Francisco; Dávila, José A; Bastos, Estela; Cabral, João A; Frías, Óscar; González, José L; Travassos, Paulo; Carvalho, Diogo; Milá, Borja; Blanco, Guillermo

    2017-05-01

    Social barriers have been shown to reduce gene flow and contribute to genetic structure among populations in species with high cognitive capacity and complex societies, such as cetaceans, apes and humans. In birds, high dispersal capacity is thought to prevent population divergence unless major geographical or habitat barriers induce isolation patterns by dispersal, colonization or adaptation limitation. We report that Iberian populations of the red-billed chough, a social, gregarious corvid with high dispersal capacity, show a striking degree of genetic structure composed of at least 15 distinct genetic units. Monitoring of marked individuals over 30 years revealed that long-distance movements over hundreds of kilometres are common, yet recruitment into breeding populations is infrequent and highly philopatric. Genetic differentiation is weakly related to geographical distance, and habitat types used are overall qualitatively similar among regions and regularly shared by individuals of different populations, so that genetic structure is unlikely to be due solely to isolation by distance or isolation by adaptation. Moreover, most population nuclei showed relatively high levels of genetic diversity, suggesting a limited role for genetic drift in significantly differentiating populations. We propose that social mechanisms may underlie this unprecedented level of genetic structure in birds through a pattern of isolation by social barriers not yet described, which may have driven this remarkable population divergence in the absence of geographical and environmental barriers. © 2017 John Wiley & Sons Ltd.

  15. Interactions between seed traits and digestive processes determine the germinability of bird-dispersed seeds.

    Science.gov (United States)

    Kleyheeg, Erik; Claessens, Mascha; Soons, Merel B

    2018-01-01

    Waterbirds disperse a wide range of plant seeds via their guts, promoting biotic connectivity between isolated habitat patches. However, the intensity of digestive forces encountered by seeds, and therefore their potential to survive digestive tract passage, varies within and between waterbird species. Here, we investigate under controlled conditions how the interaction between seed traits and digestive strategies affect the germinability of seeds following waterbird-mediated dispersal. We exposed seeds of 30 wetland plant species to the main digestive processes in the dabbling duck digestive system: mechanical, chemical and intestinal digestion. These were simulated by 1) a pressure test and scarification treatment, 2) incubation in simulated gastric juice, and 3) incubation in intestinal contents of culled mallards (Anas platyrhynchos). We evaluated their separate and combined effects on seed germination, and identified the role of seed size and seed coat traits in resisting the digestive forces. Seeds were generally resistant to separate digestive processes, but highly sensitive to a combination. Resistance to mechanical break-down was reduced by up to 80% by chemical pre-treatment, especially for seeds with permeable coats. Scarified seeds were 12-17% more vulnerable to chemical and intestinal digestive processes than undamaged seeds. Large seeds and seeds with thin, permeable coats were particularly sensitive to chemical and intestinal digestion. These results indicate that efficient digestion of seeds requires multiple digestive processes. The gizzard, responsible for mechanical digestion, plays a key role in seed survival. Omnivorous birds, which have relatively light gizzards compared to pure herbivores or granivores, are thus most likely to disperse seeds successfully. Regardless of digestive strategy, small seeds with tough seed coats are most resistant to digestion and may be adapted to endozoochorous dispersal by waterbirds.

  16. Interactions between seed traits and digestive processes determine the germinability of bird-dispersed seeds

    Science.gov (United States)

    Soons, Merel B.

    2018-01-01

    Waterbirds disperse a wide range of plant seeds via their guts, promoting biotic connectivity between isolated habitat patches. However, the intensity of digestive forces encountered by seeds, and therefore their potential to survive digestive tract passage, varies within and between waterbird species. Here, we investigate under controlled conditions how the interaction between seed traits and digestive strategies affect the germinability of seeds following waterbird-mediated dispersal. We exposed seeds of 30 wetland plant species to the main digestive processes in the dabbling duck digestive system: mechanical, chemical and intestinal digestion. These were simulated by 1) a pressure test and scarification treatment, 2) incubation in simulated gastric juice, and 3) incubation in intestinal contents of culled mallards (Anas platyrhynchos). We evaluated their separate and combined effects on seed germination, and identified the role of seed size and seed coat traits in resisting the digestive forces. Seeds were generally resistant to separate digestive processes, but highly sensitive to a combination. Resistance to mechanical break-down was reduced by up to 80% by chemical pre-treatment, especially for seeds with permeable coats. Scarified seeds were 12–17% more vulnerable to chemical and intestinal digestive processes than undamaged seeds. Large seeds and seeds with thin, permeable coats were particularly sensitive to chemical and intestinal digestion. These results indicate that efficient digestion of seeds requires multiple digestive processes. The gizzard, responsible for mechanical digestion, plays a key role in seed survival. Omnivorous birds, which have relatively light gizzards compared to pure herbivores or granivores, are thus most likely to disperse seeds successfully. Regardless of digestive strategy, small seeds with tough seed coats are most resistant to digestion and may be adapted to endozoochorous dispersal by waterbirds. PMID:29614085

  17. Use of perches and seed dispersal by birds in an abandoned pasture in the Porto Ferreira state park, southeastern Brazil

    Directory of Open Access Journals (Sweden)

    S. Athiê

    Full Text Available Abstract We investigated the efficiency of different kinds of perches in attracting seed disperser-birds and increasing the seed rain in a degraded area located in the northeast region of São Paulo State. We installed seed traps under natural perches (NPs, living trees; simple artificial perches (SAPs of 3m tall and a crossbar; elaborate artificial perches (EAPs of 7m tall and three crossbars, and in a control area. Results showed the number of bird-dispersed seeds deposited was proportional to the number of structures for perching. The NPs also have provided other resources for birds such as food and shelter. Comparing visitation between artificial perches, there was greater use of EAPs also for having more perching structures and for being taller, providing better airspace visibility for predatory birds and tyrant-flycatchers, important seed dispersers. Thus, natural and artificial perches with similar characteristics to the EAPs are the most recommended as a base or complementary method for the restoration of degraded areas near to propagules source, also contributing to the maintenance of local fauna.

  18. Potential role of frugivorous birds (Passeriformes) on seed dispersal of six plant species in a restinga habitat, southeastern Brazil.

    Science.gov (United States)

    Gomes, Verônica Souza da Mota; Correia, Maria Célia Rodrigues; de Lima, Heloisa Alves; Alves, Maria Alice S

    2008-03-01

    Restingas are considered stressful habitats associated with the Brazilian Atlantic forest, and their ecological interactions are poorly known. The goal of the present study was to determine the potential role of frugivorous birds as seed dispersers in a restinga habitat. Data were collected in Parque Nacional da Restinga de Jurubatiba, southeastern Brazil, where the main physiognomy (Open Clusia Formation) is characterized by the presence of patches of vegetation covering 20 to 48 % of the sandy soil and reaching a height of 5 m. Birds were captured with mist nets (12 x 2.5 m; 36 mm mesh; 1,680 net-hrs) and had their fecal and regurgitate samples inspected for seeds. Six plant species found in these bird samples were studied. The germination of seeds obtained from plants was compared to those from the birds. Both groups of seeds were set on Petri dishes at room temperature and washed when infected with fungi. In general, there was no effect on germination rate, and the effect on germination speed was negative. Germination of seeds from Pilosocereus arrabidae treated by the birds seemed to be influenced by storage of defecated seeds, while few Miconia cinnamomifolia seeds both from plants and from birds germinated. Ocotea notata presented a great variation in time to the onset of germination, perhaps an advantage against dissecation. Aechmea nudicaulis, Clusia hilariana and Erythroxylum subsessile probably take advantage of the arrival to favorable microhabitats, not by the gut effect on the seeds. All plant species studied are numerically important for the community and some of them are main actors in the succession of vegetation patches. Among the birds, Mimus gilvus is an important resident species, endemic to restingas in Brazil, while Turdus amaurochalinus is a visitor and may be important for plants that fructify during its passage by the study site. Although the effect of pulp removal was only tested for one species (Achmea nudicaulis) in the present study

  19. Dispersal and Transmission of Avian Paramyxovirus Serotype 4 among Wild Birds and Domestic Poultry

    Directory of Open Access Journals (Sweden)

    Renfu Yin

    2017-05-01

    Full Text Available Avian paramyxovirus serotype 4 (APMV-4 is found sporadically in wild birds worldwide, and it is an economically important poultry pathogen. Despite the existence of several published strains, very little is known about the distribution, host species, and transmission of APMV-4 strains. To better understand the relationships among these factors, we conducted an APMV-4 surveillance of wild birds and domestic poultry in six provinces of China suspected of being intercontinental flyways and sites of interspecies transmission. APMV-4 surveillance was conducted in 9,160 wild birds representing seven species, and 1,461 domestic poultry in live bird markets (LMBs from December 2013 to June 2016. The rate of APMV-4 isolation was 0.10% (11/10,621, and viruses were isolated from swan geese, bean geese, cormorants, mallards, and chickens. Sequencing and phylogenetic analyses of the 11 isolated viruses indicated that all the isolates belonging to genotype I were epidemiologically connected with wild bird-origin viruses from the Ukraine and Italy. Moreover, chicken-origin APMV-4 strains isolated from the LBMs were highly similar to wild bird-origin viruses from nearby lakes with free-living wild birds. In additional, a hemagglutination-negative APMV-4 virus was identified. These findings, together with recent APMV-4 studies, suggest potential virus interspecies transmission between wild birds and domestic poultry, and reveal possible epidemiological intercontinental connections between APMV-4 transmission by wild birds.

  20. Food supplementation mitigates dispersal-dependent differences in nest defence in a passerine bird.

    Science.gov (United States)

    Récapet, Charlotte; Daniel, Grégory; Taroni, Joëlle; Bize, Pierre; Doligez, Blandine

    2016-05-01

    Dispersing and non-dispersing individuals often differ in phenotypic traits (e.g. physiology, behaviour), but to what extent these differences are fixed or driven by external conditions remains elusive. We experimentally tested whether differences in nest-defence behaviour between dispersing and non-dispersing individuals changed with local habitat quality in collared flycatchers, by providing additional food during the nestling rearing period. In control (non-food-supplemented) nests, dispersers were less prone to defend their brood compared with non-dispersers, whereas in food-supplemented nests, dispersing and non-dispersing individuals showed equally strong nest defence. We discuss the importance of dispersal costs versus adaptive flexibility in reproductive investment in shaping these differences in nest-defence behaviour between dispersing and non-dispersing individuals. Irrespective of the underlying mechanisms, our study emphasizes the importance of accounting for environmental effects when comparing traits between dispersing and non-dispersing individuals, and in turn assessing the costs and benefits of dispersal. © 2016 The Author(s).

  1. Potential role of frugivorous birds (Passeriformes on seed dispersal of six plant species in a restinga habitat, southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Verônica Souza da Mota Gomes

    2008-03-01

    Full Text Available Restingas are considered stressful habitats associated with the Brazilian Atlantic forest, and their ecological interactions are poorly known. The goal of the present study was to determine the potential role of frugivorous birds as seed dispersers in a restinga habitat. Data were collected in Parque Nacional da Restinga de Jurubatiba, southeastern Brazil, where the main physiognomy (Open Clusia Formation is characterized by the presence of patches of vegetation covering 20 to 48 % of the sandy soil and reaching a height of 5 m. Birds were captured with mist nets (12 x 2.5 m; 36 mm mesh; 1 680 net-hrs and had their fecal and regurgitate samples inspected for seeds. Six plant species found in these bird samples were studied. The germination of seeds obtained from plants was compared to those from the birds. Both groups of seeds were set on Petri dishes at room temperature and washed when infected with fungi. In general, there was no effect on germination rate, and the effect on germination speed was negative. Germination of seeds from Pilosocereus arrabidae treated by the birds seemed to be influenced by storage of defecated seeds, while few Miconia cinnamomifolia seeds both from plants and from birds germinated. Ocotea notata presented a great variation in time to the onset of germination, perhaps an advantage against dissecation. Aechmea nudicaulis, Clusia hilariana and Erythroxylum subsessile probably take advantage of the arrival to favorable microhabitats, not by the gut effect on the seeds. All plant species studied are numerically important for the community and some of them are main actors in the succession of vegetation patches. Among the birds, Mimus gilvus is an important resident species, endemic to restingas in Brazil, while Turdus amaurochalinus is a visitor and may be important for plants that fructify during its passage by the study site. Although the effect of pulp removal was only tested for one species (Achmea nudicaulis in the

  2. Refractive index and dispersion of butterfly chitin and bird keratin measured by polarizing interference microscopy

    NARCIS (Netherlands)

    Leertouwer, Hein L.; Wilts, Bodo D.; Stavenga, Doekele G.

    2011-01-01

    Using Jamin-Lebedeff interference microscopy, we measured the wavelength dependence of the refractive index of butterfly wing scales and bird feathers. The refractive index values of the glass scales of the butterfly Graphium sarpedon are, at wavelengths 400, 500 and 600 nm, 1.572, 1.552 and 1.541,

  3. Contrasting patterns of survival and dispersal in multiple habitats reveal an ecological trap in a food-caching bird.

    Science.gov (United States)

    Norris, D Ryan; Flockhart, D T Tyler; Strickland, Dan

    2013-11-01

    A comprehensive understanding of how natural and anthropogenic variation in habitat influences populations requires long-term information on how such variation affects survival and dispersal throughout the annual cycle. Gray jays Perisoreus canadensis are widespread boreal resident passerines that use cached food to survive over the winter and to begin breeding during the late winter. Using multistate capture-recapture analysis, we examined apparent survival and dispersal in relation to habitat quality in a gray jay population over 34 years (1977-2010). Prior evidence suggests that natural variation in habitat quality is driven by the proportion of conifers on territories because of their superior ability to preserve cached food. Although neither adults (>1 year) nor juveniles (conifer territories, both age classes were less likely to leave high-conifer territories and, when they did move, were more likely to disperse to high-conifer territories. In contrast, survival rates were lower on territories that were adjacent to a major highway compared to territories that did not border the highway but there was no evidence for directional dispersal towards or away from highway territories. Our results support the notion that natural variation in habitat quality is driven by the proportion of coniferous trees on territories and provide the first evidence that high-mortality highway habitats can act as an equal-preference ecological trap for birds. Reproductive success, as shown in a previous study, but not survival, is sensitive to natural variation in habitat quality, suggesting that gray jays, despite living in harsh winter conditions, likely favor the allocation of limited resources towards self-maintenance over reproduction.

  4. Potential roles of fish, birds, and water in swamp privet (Forestiera acuminata) seed dispersal

    Science.gov (United States)

    Susan B. Adams; Paul B. Hamel; Kristina Connor; Bryce Burke; Emile S. Gardiner; David Wise

    2007-01-01

    Forestiera acuminata (swamp privet) is a common wetland shrub/small tree native to the southeastern United States. We examined several possible dispersal avenues for the plant. We tested germination of seeds exposed to various treatments, including passage through Ictalurus punctatus (Channel Catfi sh) guts, and conducted other...

  5. Interactions between seed traits and digestive processes determine the germinability of bird-dispersed seeds

    NARCIS (Netherlands)

    Kleyheeg, Erik; Claessens, Mascha; Soons, Merel B.

    2018-01-01

    Waterbirds disperse a wide range of plant seeds via their guts, promoting biotic connectivity between isolated habitat patches. However, the intensity of digestive forces encountered by seeds, and therefore their potential to survive digestive tract passage, varies within and between waterbird

  6. The European and Japanese outbreaks of H5N8 derive from a single source population providing evidence for the dispersal along the long distance bird migratory flyways

    Directory of Open Access Journals (Sweden)

    Andrew R. Dalby

    2015-04-01

    Full Text Available The origin of recent parallel outbreaks of the high pathogenicity H5N8 avian flu virus in Europe and in Japan can be traced to a single source population, which has most likely been spread by migratory birds. By using Bayesian coalescent methods to analyze the DNA sequences of the virus to find the times for divergence and combining this sequence data with bird migration data we can show the most likely locations and migratory pathways involved in the origin of the current outbreak. This population was most likely located in the Siberian summer breeding grounds of long-range migratory birds. These breeding grounds provide a connection between different migratory flyways and explain the current outbreaks in remote locations. By combining genetic methods and epidemiological data we can rapidly identify the sources and the dispersion pathways for novel avian influenza outbreaks.

  7. Estimating dispersal rates of Steller sea lion (Eumetopias jubatus mother-pup pairs from a natal rookery using mark-resight data.

    Directory of Open Access Journals (Sweden)

    Carey E Kuhn

    Full Text Available To monitor population trends of Steller sea lions (Eumetopias jubatus in Alaska, newborn pups are counted during aerial surveys. These surveys are scheduled to occur after the majority of pups are born, but before pups begin to spend significant time in the water. Some studies have reported dispersal of mother-pup pairs away from breeding beaches during the pupping season (July, which may influence survey results. Using a multistate mark-recapture model with state uncertainty, we estimated the amount of dispersal during the pupping season based on observations of permanently marked sea lions. Research was conducted at land-based observation sites on Marmot Island, Alaska, between 2000 and 2013. Both marked adult females with dependent pups and marked pups were observed at two rookery beaches from May to July. Cumulative dispersal rates were minimal (< 1% prior to the planned start of the aerial survey (23 June and increased to 11.2% by the planned survey completion date (10 July. The increased cumulative dispersal rate during the remainder of the observation period (end of July suggests potential bias in surveys that occur beyond 10 July, however surveys past this date are rare (< 10% between 1973 and 2016. As a result, movements of mother-pup pairs during the pupping season are not likely to influence aerial survey estimates.

  8. Potential bird dispersers of Psychotria in a area of Atlantic forest on Ilha Grande, RJ, Southeastern Brazil: a biochemical analysis of the fruits

    Directory of Open Access Journals (Sweden)

    E. M. Almeida

    Full Text Available The present study assessed the fruiting pattern, bird foraging behavior, and sugar content of ripe fruits of two sympatric species of Rubiaceae (Psychotria brasiliensis and P. nuda. This study was carried out in an Atlantic forest area on Ilha Grande, RJ, between August 1998 and July 1999. Fruit production occurred year round, with a peak of mature P. brasiliensis fruits in December 1998 and another of P. nuda in February of 1999. Lipaugus lanioides (Cotingidae, Baryphtengus ruficapillus (Momotidae and Saltator similis (Emberizidae made the most frequent foraging visits to fruiting P. brasiliensis, so that L. lanioides and B. ruficapillus removed the fruits with sallying maneuvers while S. similis gleaned the fruits. Lipaugus lanioides was by far the most important consumer, and potentially the main disperser of P. brasiliensis. Birds of this genus are heavy frugivores in the tropical forests and are widely assumed to be important seed dispersers. The fruits were analyzed quantitatively and qualitatively in relation to the amounts of sucrose and starch. Psychotria brasiliensis (the visited species showed the smallest quantity of sucrose and the highest amount of starch. These findings suggest that what may influence the birds' choice of fruit is the proportion of starch in the Psychotria species studied here rather than the carbohydrate composition.

  9. Explaining LIGO's observations via isolated binary evolution with natal kicks

    Science.gov (United States)

    Wysocki, Daniel; Gerosa, Davide; O'Shaughnessy, Richard; Belczynski, Krzysztof; Gladysz, Wojciech; Berti, Emanuele; Kesden, Michael; Holz, Daniel E.

    2018-02-01

    We compare binary evolution models with different assumptions about black-hole natal kicks to the first gravitational-wave observations performed by the LIGO detectors. Our comparisons attempt to reconcile merger rate, masses, spins, and spin-orbit misalignments of all current observations with state-of-the-art formation scenarios of binary black holes formed in isolation. We estimate that black holes (BHs) should receive natal kicks at birth of the order of σ ≃200 (50 ) km /s if tidal processes do (not) realign stellar spins. Our estimate is driven by two simple factors. The natal kick dispersion σ is bounded from above because large kicks disrupt too many binaries (reducing the merger rate below the observed value). Conversely, the natal kick distribution is bounded from below because modest kicks are needed to produce a range of spin-orbit misalignments. A distribution of misalignments increases our models' compatibility with LIGO's observations, if all BHs are likely to have natal spins. Unlike related work which adopts a concrete BH natal spin prescription, we explore a range of possible BH natal spin distributions. Within the context of our models, for all of the choices of σ used here and within the context of one simple fiducial parameterized spin distribution, observations favor low BH natal spin.

  10. Spatial distribution of breeding Pied Flycatchers Ficedula hypoleuca in respect to their natal sites

    Directory of Open Access Journals (Sweden)

    Sokolov, L.

    2004-06-01

    Full Text Available Study of philopatry and dispersal of pied flycatchers Ficedula hypoleuca was launched on the Courish Spit (SE Baltic in 1981. Since then, ca. 9,000 nestlings were ringed at different sites in the Russian part of the Courish Spit. A total of 557 individuals ringed as pulli were recaptured in subsequent seasons in the study area. Both males and females are more often recaptured in the plots where they were ringed than in other plots. These results were interpreted in the framework of the hypothesis forwarded by Löhrl (1959 and supported by Berndt & Winkel (1979. These authors suggested that cavity nesters (pied flycatchers and collared flycatchers F. albicollis imprint their future local breeding area during the period of postfledging exploration. Birds that survive until the next spring, return to these imprinted areas to breed. A similar study done by Sokolov et al. (1984 on the Courish Spit in an open nesting species, the chaffinch Fringilla coelebs, confirmed this finding. We assumed that juvenile pied flycatchers disperse for varying distances during their postfledging movements and imprint a local area, some 1–5 kilometres in diameter. This area is the goal of their migration next spring. It is suggested that in spring, yearlings are non–randomly distributed in respect to the area they have imprinted as juveniles. Recently, Vysotsky (2000, 2001 re–analysed the same data on philopatry of pied flycatchers on the Courish Spit and forwarded an alternative hypothesis. He suggests that juveniles, both males and females, do not imprint any local area during the postfledging period, but are distributed randomly across the area of several dozens of kilometres in spring. Vysotsky was able to show that distribution of distances of natal dispersal did not differ from the random pattern the study plot which was an 8.5 km long line of nest boxes along the Courish Spit. The aim of this study was to test these two alternative hypotheses. To do so, we

  11. The Influence of Kinship on Familiar Natal Migrant Rhesus Macaques (Macaca mulatta)

    Science.gov (United States)

    Albers, Monika; Widdig, Anja

    2014-01-01

    In most primate species, females remain in the natal group with kin while males disperse away from kin around the time of puberty. Philopatric females bias their social behavior toward familiar maternal and paternal kin in several species, but little is known about kin bias in the dispersing sex. Male dispersal is likely to be costly because males encounter an increased risk of predation and death, which might be reduced by dispersing together with kin and/or familiar males (individuals that were born and grew up in same natal group) or into a group containing kin and/or familiar males. Here we studied the influence of kinship on familiar natal migrant rhesus macaques (Macaca mulatta) on Cayo Santiago, Puerto Rico, by combining demographic, behavioral, and genetic data. Our data suggest that kinship influences spatial proximity between recent natal immigrants and males familiar to them. Immigrants were significantly nearer to more closely related familiar males than to more distantly related individuals. Within a familiar subgroup, natal migrants were significantly closer to maternal kin, followed by paternal kin, then non-kin, and finally to males related via both the maternal and paternal line. Spatial proximity between natal immigrants and familiar males did not decrease over time in the new group, suggesting that there is no decline in associations between these individuals within the first months of immigration. Overall, our results might indicate that kinship is important for the dispersing sex, at least during natal dispersal when kin are still available. PMID:24850977

  12. Dispersal Timing: Emigration of Insects Living in Patchy Environments.

    Directory of Open Access Journals (Sweden)

    Milica Lakovic

    Full Text Available Dispersal is a life-history trait affecting dynamics and persistence of populations; it evolves under various known selective pressures. Theoretical studies on dispersal typically assume 'natal dispersal', where individuals emigrate right after birth. But emigration may also occur during a later moment within a reproductive season ('breeding dispersal'. For example, some female butterflies first deposit eggs in their natal patch before migrating to other site(s to continue egg-laying there. How breeding compared to natal dispersal influences the evolution of dispersal has not been explored. To close this gap we used an individual-based simulation approach to analyze (i the evolution of timing of breeding dispersal in annual organisms, (ii its influence on dispersal (compared to natal dispersal. Furthermore, we tested (iii its performance in direct evolutionary contest with individuals following a natal dispersal strategy. Our results show that evolution should typically result in lower dispersal under breeding dispersal, especially when costs of dispersal are low and population size is small. By distributing offspring evenly across two patches, breeding dispersal allows reducing direct sibling competition in the next generation whereas natal dispersal can only reduce trans-generational kin competition by producing highly dispersive offspring in each generation. The added benefit of breeding dispersal is most prominent in patches with small population sizes. Finally, the evolutionary contests show that a breeding dispersal strategy would universally out-compete natal dispersal.

  13. The causes of dispersal and the cost of carry-over effects for an endangered bird in a dynamic wetland landscape.

    Science.gov (United States)

    Robertson, Ellen P; Fletcher, Robert J; Austin, James D

    2017-07-01

    The decision to disperse or remain philopatric between breeding seasons has important implications for both ecology and evolution, including the potential for carry-over effects, where an individual's previous history affects its current performance. Carry-over effects are increasingly documented although underlying mechanisms remain unclear. Here we test for potential carry-over effects and their mechanisms by uniting hypotheses for the causes and consequences of habitat selection and dispersal across space and time. We linked hypotheses regarding different types of factors and information (environmental conditions, personal and public information) predicted to impact reproductive success and dispersal for an endangered, wetland-dependent bird, the snail kite (Rostrhamus sociabilis plumbeus). To do so, we coupled structural equation modelling with 20 years of mark-recapture and nesting data across the breeding range of this species to isolate potential direct and indirect effects of these factors. We found that water depth at nest sites explained subsequent emigration rates via an indirect path through the use of personal, not public, information. Importantly, we found that these dispersers tended to initiate nests later the following breeding season. This pattern explained a phenological mismatch of nesting with hydrological conditions, whereby immigrants tended to nest later, late nesters tended to experience lower water depths, higher nest failure occurred at lower water depths and higher nest failure explained subsequent breeding dispersal. These results identified a novel potential mechanism for carry-over effects: a phenological mismatch with environmental conditions (water depth) that occurred potentially due to time costs of dispersal. Our results also highlighted a substantial benefit of philopatry - earlier initiation of reproduction - which allows philopatric individuals to better coincide with environmental conditions that are beneficial for

  14. REBATIMENTOS EM NATAL, BRASIL

    Directory of Open Access Journals (Sweden)

    Fábio Fonseca Figueiredo

    2013-01-01

    Full Text Available El artículo presenta la gestión de los residuos sólidos en Brasil y sus implicaciones en la ciudad de Natal/ RN, analizando sus aspectos ambientales, económicos y sociales. El fracaso del programa oficial de recogi - da selectiva constatado en las bajas tasas de recuperación de materiales; la poca relevancia de la inclusión socioeconómica de los trabajadores que participan en el programa asistencialista oficial; la inexistencia de estrategias oficiales para que se disminuya la cantidad de residuos que se generan cada día y el aumento exagerado del gasto público, especialmente con el tratamiento de los residuos en el relleno sanitario, demues - tran que la gestión de residuos en Natal, que tiene como parámetro los dictámenes de la Política Brasileña para los Residuos Sólidos, tiene como objetivo el control de los residuos en la ciudad y la consolidación del modelo de tratamiento finalista de residuos mediante el envío de éstos al relleno sanitario.

  15. The Bird.

    Science.gov (United States)

    Hannon, Jean

    2001-01-01

    Students use a dead bird to learn about bird life, anatomy, and death. Students examine a bird body and discuss what happened to the bird. Uses outdoor education as a resource for learning about animals. (SAH)

  16. Virginia ESI: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, raptors, diving birds, pelagic birds, passerine birds, and gulls...

  17. Effects of natal departure and water level on survival of juvenile snail kites (Rostrhamus sociabilis) in Florida

    Science.gov (United States)

    Dreitz, V.J.; Kitchens, W.M.; DeAngelis, D.L.

    2004-01-01

    Survival rate from fledging to breeding, or juvenile survival, is an important source of variation in lifetime reproductive success in birds. Therefore, determining the relationship between juvenile survival and environmental factors is essential to understanding fitness consequences of reproduction in many populations. With increases in density of individuals and depletion of food resources, quality of most habitats deteriorates during the breeding season. Individuals respond by dispersing in search of food resources. Therefore, to understand the influence of environmental factors on juvenile survival, it is also necessary to know how natal dispersal influences survival of juveniles. We examined effects of various environmental factors and natal dispersal behavior on juvenile survival of endangered Snail Kites (Rostrhamus sociabilis) in central and southern Florida, using a generalized estimating equations (GEEs) approach and model selection criteria. Our results suggested yearly effects and an influence of age and monthly minimum hydrologic levels on juvenile Snail Kite survival. Yearly variation in juvenile survival has been reported by other studies, and other reproductive components of Snail Kites also exhibit such variation. Age differences in juvenile survival have also been seen in other species during the juvenile period. Our results demonstrate a positive relationship between water levels and juvenile survival. We suggest that this is not a direct linear relationship, such that higher water means higher juvenile survival. The juvenile period is concurrent with onset of the wet season in the ecosystem we studied, and rainfall increases as juveniles age. For management purposes, we believe that inferences suggesting increasing water levels during the fledging period will increase juvenile survival may have short-term benefits but lead to long-term declines in prey abundance and possibly wetland vegetation structure.

  18. Nest-site fidelity and dispersal of Gyrfalcons estimated by noninvasive genetic sampling

    Science.gov (United States)

    Booms, T.L.; Talbot, S.L.; Sage, G.K.; McCaffery, B.J.; McCracken, K.G.; Schempf, P.F.

    2011-01-01

    We used feathers from adult Gyrfalcons (Falco rusticolus) molted in breeding territories and blood samples from nestlings to document nest-site fidelity and dispersal of breeding adults and juveniles at three areas 100- 350 km apart in Yukon Delta National Wildlife Refuge, Alaska, 2003-2007. We used genotypes from seven polymorphic microsatellite loci that provided a mean probability of identity of 0.91 ??10 -5. Breeding Gyrfalcons were highly faithful to study area and territory; we documented no dispersals of breeding birds among study areas and only one dispersal between territories. But their fidelity to nest sites was low; 22% of birds returned to the same nest site the following year. Distance among alternate nests within a territory averaged 750 m and was similar for both sexes. Mean tenure in a territory was 2.8 years, similar for both sexes, and distributed bimodally with peaks at 1 and 4 years. Mean annual turnover rate at the Ingakslugwat Hills (Volcanoes) study area was 20%. We detected three young that established breeding territories at distances ranging from 0 to 254 km from their natal territory, representing 2.5% apparent recruitment. Gyrfalcons in the Askinuk Mountains study area were slightly but statistically significantly differentiated genetically from those in the Volcanoes and Kilbuck Mountain study areas. These data are the first published on the nest-site fidelity, breeding dispersal, and natal dispersal of the Gyrfalcon in North America and demonstrate the utility of noninvasive genetic sampling to greatly improve our understanding of avian dispersal and its underlying mechanisms. ?? The Cooper Ornithological Society 2011.

  19. Dispersal and survival rates of adult and juvenile Red-tailed tropicbirds (Phaethon rubricauda exposed to potential contaminants

    Directory of Open Access Journals (Sweden)

    Schreiber, E. A.

    2004-06-01

    Full Text Available Annual survival and dispersal rates of adult and juvenile red-tailed tropicbirds were examined in connection with exposure to heavy metals. From 1990-2000 the incineration of a U.S. stockpile of chemical weapons stored at Johnston Atoll exposed nesting tropicbirds to increased levels of human disturbance, smoke stack emissions and potential leaks. Using a multi-state mark-recapture modeling approach, birds nesting in this site (downwind of the plant were compared to those nesting in a reference site (upwind of the plant with less human disturbance, no exposure to smoke stack emissions or other potential incineration emissions. We did not find any difference in survival of adults or juveniles when comparing the two sites. Adult breeding dispersal rates did not differ between the sites but we did find differences in the age-specific natal dispersal rates. Birds fledged from downwind areas were less likely to return to their natal area to nest and more likely to immigrate to the upwind area than vice-versa. This asymmetry in emigration rates is believed to be due to differing vegetation densities and has implications for vegetation management in relation to tropicbird nest success and population size.

  20. Alabama ESI: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, raptors, diving birds, seabirds, passerine birds, gulls, and terns...

  1. Maryland ESI: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, raptors, diving birds, seabirds, passerine birds, and gulls and...

  2. War rape, natality and genocide.

    Science.gov (United States)

    Schott, Robin May

    2011-01-01

    Feminist philosophy can make an important contribution to the field of genocide studies, and issues relating to gender and war are gaining new attention. In this article I trace legal and philosophical analyses of sexual violence against women in war. I analyze the strengths and limitations of the concept of social death—introduced into this field by Claudia Card—for understanding the genocidal features of war rape, and draw on the work of Hannah Arendt to understand the central harm of genocide as an assault on natality. The threat to natality posed by the harms of rape, forced pregnancy and forced maternity lie in the potential expulsion from the public world of certain groups—including women who are victims, members of the 'enemy' group, and children born of forced birth.

  3. Sexual selection affects local extinction and turnover in bird communities

    Science.gov (United States)

    Doherty, P.F.; Sorci, G.; Royle, J. Andrew; Hines, J.E.; Nichols, J.D.; Boulinier, T.

    2003-01-01

    Predicting extinction risks has become a central goal for conservation and evolutionary biologists interested in population and community dynamics. Several factors have been put forward to explain risks of extinction, including ecological and life history characteristics of individuals. For instance, factors that affect the balance between natality and mortality can have profound effects on population persistence. Sexual selection has been identified as one such factor. Populations under strong sexual selection experience a number of costs ranging from increased predation and parasitism to enhanced sensitivity to environmental and demographic stochasticity. These findings have led to the prediction that local extinction rates should be higher for species/populations with intense sexual selection. We tested this prediction by analyzing the dynamics of natural bird communities at a continental scale over a period of 21 years (1975-1996), using relevant statistical tools. In agreement with the theoretical prediction, we found that sexual selection increased risks of local extinction (dichromatic birds had on average a 23% higher local extinction rate than monochromatic species). However, despite higher local extinction probabilities, the number of dichromatic species did not decrease over the period considered in this study. This pattern was caused by higher local turnover rates of dichromatic species, resulting in relatively stable communities for both groups of species. Our results suggest that these communities function as metacommunities, with frequent local extinctions followed by colonization. Anthropogenic factors impeding dispersal might therefore have a significant impact on the global persistence of sexually selected species.

  4. Nest-mediated seed dispersal

    Science.gov (United States)

    Robert J. Warren; Jason P. Love; Mark A. Bradford

    2017-01-01

    Many plant seeds travel on the wind and through animal ingestion or adhesion; however, an overlooked dispersal mode may lurk within those dispersal modes. Viable seeds may remain attached or embedded within materials birds gather for nest building. Our objective was to determine if birds inadvertently transport seeds when they forage for plant materials to...

  5. Screamy Bird

    DEFF Research Database (Denmark)

    Tarby, Sara; Cermak, Daniel

    2016-01-01

    Sara Tarby, Daniel Cermak-Sassenrath. Screamy Bird. Digital game. Kulturnatten 2016, Danish Science Ministry, Copenhagen, DK, Oct 14, 2016.......Sara Tarby, Daniel Cermak-Sassenrath. Screamy Bird. Digital game. Kulturnatten 2016, Danish Science Ministry, Copenhagen, DK, Oct 14, 2016....

  6. Geomagnetic imprinting: A unifying hypothesis of long-distance natal homing in salmon and sea turtles.

    Science.gov (United States)

    Lohmann, Kenneth J; Putman, Nathan F; Lohmann, Catherine M F

    2008-12-09

    Several marine animals, including salmon and sea turtles, disperse across vast expanses of ocean before returning as adults to their natal areas to reproduce. How animals accomplish such feats of natal homing has remained an enduring mystery. Salmon are known to use chemical cues to identify their home rivers at the end of spawning migrations. Such cues, however, do not extend far enough into the ocean to guide migratory movements that begin in open-sea locations hundreds or thousands of kilometers away. Similarly, how sea turtles reach their nesting areas from distant sites is unknown. However, both salmon and sea turtles detect the magnetic field of the Earth and use it as a directional cue. In addition, sea turtles derive positional information from two magnetic elements (inclination angle and intensity) that vary predictably across the globe and endow different geographic areas with unique magnetic signatures. Here we propose that salmon and sea turtles imprint on the magnetic field of their natal areas and later use this information to direct natal homing. This novel hypothesis provides the first plausible explanation for how marine animals can navigate to natal areas from distant oceanic locations. The hypothesis appears to be compatible with present and recent rates of field change (secular variation); one implication, however, is that unusually rapid changes in the Earth's field, as occasionally occur during geomagnetic polarity reversals, may affect ecological processes by disrupting natal homing, resulting in widespread colonization events and changes in population structure.

  7. Geomagnetic imprinting: A unifying hypothesis of long-distance natal homing in salmon and sea turtles

    Science.gov (United States)

    Lohmann, Kenneth J.; Putman, Nathan F.; Lohmann, Catherine M. F.

    2008-01-01

    Several marine animals, including salmon and sea turtles, disperse across vast expanses of ocean before returning as adults to their natal areas to reproduce. How animals accomplish such feats of natal homing has remained an enduring mystery. Salmon are known to use chemical cues to identify their home rivers at the end of spawning migrations. Such cues, however, do not extend far enough into the ocean to guide migratory movements that begin in open-sea locations hundreds or thousands of kilometers away. Similarly, how sea turtles reach their nesting areas from distant sites is unknown. However, both salmon and sea turtles detect the magnetic field of the Earth and use it as a directional cue. In addition, sea turtles derive positional information from two magnetic elements (inclination angle and intensity) that vary predictably across the globe and endow different geographic areas with unique magnetic signatures. Here we propose that salmon and sea turtles imprint on the magnetic field of their natal areas and later use this information to direct natal homing. This novel hypothesis provides the first plausible explanation for how marine animals can navigate to natal areas from distant oceanic locations. The hypothesis appears to be compatible with present and recent rates of field change (secular variation); one implication, however, is that unusually rapid changes in the Earth's field, as occasionally occur during geomagnetic polarity reversals, may affect ecological processes by disrupting natal homing, resulting in widespread colonization events and changes in population structure. PMID:19060188

  8. Timing of natal nests is an important factor affecting return rates of juvenile Great Reed Warblers

    Czech Academy of Sciences Publication Activity Database

    Sosnovcová, Kateřina; Koleček, Jaroslav; Požgayová, Milica; Jelínek, Václav; Šulc, Michal; Steidlová, Petra; Honza, Marcel; Procházka, Petr

    2018-01-01

    Roč. 159, č. 1 (2018), s. 183-190 ISSN 0021-8375 R&D Projects: GA ČR GA13-06451S Institutional support: RVO:68081766 Keywords : Acrocephalus arundinaceus * Juvenile condition * Juvenile survival * Local dispersal distances * Natal philopatry Subject RIV: EG - Zoology OBOR OECD: Ornithology Impact factor: 1.468, year: 2016

  9. Survey of September 1987 Natal floods

    CSIR Research Space (South Africa)

    Badenhorst, P

    1989-01-01

    Full Text Available During the September 1987 floods in Natal various organisations collaborated by observing the effects of the floods. The efforts of the CSIR in Stellenbosch and Durban, and the Geology Departments of the Universities of Natal and Port Elizabeth were...

  10. The ecology of sandy beaches in Natal

    African Journals Online (AJOL)

    The ecology of sandy beaches in Natal. A.H. Dye, A. Mclachlan and T. Wooldridge. Department of Zoology, University of Port Elizabeth, Port Elizabeth. Data from an ecological survey of four sandy beaches on the. Natal coast of South Africa are presented. Physical para· meters such as beach profile, particle size, moisture, ...

  11. The effect of colostrum on pigs pre-natally or post-natally exposed to Schistosoma japonicum

    DEFF Research Database (Denmark)

    Techau, M.E.; Johansen, M.V.; Lind, Peter

    2004-01-01

    Pre-natal infection of Schistosoma japonicum in pigs may prove to be a useful model in shedding light on human pre-natal schistosomiasis. This study describes the effects of immune colostrum on worm burdens, tissue egg counts, liver pathology and crude worm or egg antigen-specific IgG and Ig......A responses, in groups of pigs pre-natally, pre-natally + post-natally or post-natally exposed to S. japonicum. Results suggest that pre-natal exposure and immune colostrum did not affect the establishment of a post-natal challenge infection. However, immune colostrum seemed to increase the levels of septal...

  12. No sex-biased dispersal in a primate with an uncommon social system—cooperative polyandry

    Directory of Open Access Journals (Sweden)

    Samuel L. Díaz-Muñoz

    2014-10-01

    Full Text Available An influential hypothesis proposed by Greenwood (1980 suggests that different mating systems result in female and male-biased dispersal, respectively, in birds and mammals. However, other aspects of social structure and behavior can also shape sex-biased dispersal. Although sex-specific patterns of kin cooperation are expected to affect the benefits of philopatry and dispersal patterns, empirical evidence is scarce. Unlike many mammals, Saguinus geoffroyi (Geoffroy’s tamarin has a breeding system in which typically multiple males mate with a single breeding female. Males typically form cooperative reproductive partnerships between relatives, whereas females generally compete for reproductive opportunities. This system of cooperative polyandry is predicted to result in female-biased dispersal, providing an opportunity to test the current hypotheses of sex-biased dispersal. Here we test for evidence of sex-biased dispersal in S. geoffroyi using demographic and genetic data from three populations. We find no sex bias in natal dispersal, contrary to the prediction based on the mating patterns. This pattern was consistent after controlling for the effects of historical population structure. Limited breeding opportunities within social groups likely drive both males and females to disperse, suggesting that dispersal is intimately related to the social context. The integration of genetic and field data revealed that tamarins are another exception to the presumed pattern of male-biased dispersal in mammals. A shift in focus from mating systems to social behavior, which plays a role in most all processes expected to influence sex-bias in dispersal, will be a fruitful target for research both within species and across taxa.

  13. Natal and breeding philopatry of female Steller sea lions in southeastern Alaska.

    Directory of Open Access Journals (Sweden)

    Kelly K Hastings

    Full Text Available Information on drivers of dispersal is critical for wildlife conservation but is rare for long-lived marine mammal species with large geographic ranges. We fit multi-state mark-recapture models to resighting data of 369 known-aged Steller sea lion (Eumetopias jubatus females marked as pups on their natal rookeries in southeastern Alaska from 1994-2005 and monitored from 2001-15. We estimated probabilities of females being first observed parous at their natal site (natal philopatry, and of not moving breeding sites among years (breeding philopatry at large (> 400 km, all five rookeries in southeastern Alaska and small (< 4 km, all islands within the largest rookery, Forrester Island Complex, F spatial scales. At the rookery scale, natal philopatry was moderately high (0.776-0.859 for most rookeries and breeding philopatry was nearly 1, with < 3% of females switching breeding rookeries between years. At more populous islands at F, natal philopatry was 0.500-0.684 versus 0.295-0.437 at less populous islands, and breeding philopatry was 0.919-0.926 versus 0.604-0.858. At both spatial scales, the probability of pupping at a non-natal site increased with population size of, and declined with distance from, the destination site. Natal philopatry of < 1 would increase gene flow, improve population resilience, and promote population recovery after decline in a heterogeneous environment. Very high breeding philopatry suggests that familiarity with neighboring females and knowledge of the breeding site (the topography of pupping sites and nearby foraging locations may be a critical component to reproductive strategies of sea lions.

  14. Bird guard

    Science.gov (United States)

    Fairchild, Dana M [Armour, SD

    2010-03-02

    The bird guard provides a device to protect electrical insulators comprising a central shaft; a clamp attached to an end of the shaft to secure the device to a transmission tower; a top and bottom cover to shield transmission tower insulators; and bearings to allow the guard to rotate in order to frighten birds away from the insulators.

  15. Genetic insights into dispersal distance and disperser fitness of African lions (Panthera leo) from the latitudinal extremes of the Kruger National Park, South Africa

    NARCIS (Netherlands)

    Hooft, van Pim; Keet, Dewald F.; Brebner, Diana K.; Bastos, Armanda D.S.

    2018-01-01

    Background: Female lions generally do not disperse far beyond their natal range, while males can disperse distances of over 200 km. However, in bush-like ecosystems dispersal distances less than 25 km are reported. Here, we investigate dispersal in lions sampled from the northern and southern

  16. Exito reproductivo de plantas ornitócoras en un relicto de selva subtropical en Argentina Reproductive success of bird-dispersed plants in a subtropical forest relict in Argentina

    Directory of Open Access Journals (Sweden)

    NORBERTO H. MONTALDO

    2000-09-01

    Full Text Available En un relicto de selva ribereña situado en la región central de Argentina (Punta Lara, provincia de Buenos Aires se estudió la fenología reproductiva, y la producción y dispersión de diásporas de cinco especies arbóreas nativas y de dos malezas exóticas (Rubus ulmifolius y Ligustrum lucidum. Además se determinó el poder germinativo de las semillas y la tasa de reclutamiento y características de las plántulas. En el último medio siglo las malezas invadieron la selva, amenazando actualmente con destruirla. El elenco de aves frugívoras del área es reducido y está integrado por siete especies residentes y una migratoria. Hay plantas nativas que manifiestan limitaciones reproductivas por escasa producción y/o dispersión de diásporas. Si bien las plantas exóticas no superan significativamente a las nativas en las relaciones fruto/ flor y frutos consumidos/ frutos disponibles, las primeras tienen ventajas en la cantidad de semillas que incorporan al medio por unidad (m2 de superficie de copa (ca. 1700 vs. 800 en la nativa que más dispersa, y en su germinación abundante (Ligustrum o en la habilidad competitiva de sus plántulas (Rubus. El éxito de las malezas se explicaría en gran parte por su agresividad intrínseca y por la situación de marginalidad ecológica de esta comunidad selvática, ya que muchas especies se encuentran en el extremo meridional de su distribuciónReproductive phenology, diaspore production, diaspore removal, and seed-dispersal by birds of five indigenous and two alien (Rubus ulmifolius and Ligustrum lucidum woody species were studied in a riparian forest relict located in central Argentina (Punta Lara, Buenos Aires Province. Seed germination, recruitment, and seedling traits of these plants were also determined. During the last half century the weeds heavily invaded the forest, presently constituting a serious threat to the survival of this natural community. In the area the fruit-eating bird assemblage

  17. Hawaii ESI: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for endangered waterbirds and passerine birds, migratory shorebirds and waterfowl, gulls and terns,...

  18. Parent presence, delayed dispersal, and territory acquisition in the Seychelles warbler

    NARCIS (Netherlands)

    Eikenaar, C.; Richardson, D. S.; Komdeur, J.

    2007-01-01

    The presence of parents in the natal territory may play an important, but often overlooked, role in natal dispersal and the consequent acquisition of a territory. Living with parents in a territory may confer a fitness advantage to subordinates through, for example, the nepotistic behavior of the

  19. Natal Teeth, Case Report and Review

    OpenAIRE

    Fierro Monti, Claudia; Bravo Rivera, Lorena; Torres Chianale, Francisca; Álvarez Helle, Camila; Pérez Flores, Ma Antonieta

    2010-01-01

    Los dientes natales y neonatales deben valorarse con mucho cuidado; estimando su movilidad, integridad y la presencia de una úlcera (Riga Fede) en la superficie ventral de la lengua causada por su roce con el diente. Los dientes natales podrían parecerse a la dentición temporal normal en tamaño y forma, sin embargo, también pueden presentarse más pequeños, cónicos, con esmalte y dentina hipoplásicos, con poca formación o ausencia de sus raíces. La mayoría de estos dientes no son supernumerari...

  20. Columbia River ESI: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, diving birds, seabirds, passerine birds, gulls, and terns in...

  1. Hilton College Farm School, Natal, South Africa.

    Science.gov (United States)

    Beveridge, Sue

    1989-01-01

    The Hilton College Farm School is a primary school providing for the educational needs of children in a rural area of Natal, South Africa. Described are the school's historical development, funding sources, staffing, and development of an affiliated pre-primary school. (JDD)

  2. Natal Host Plants Can Alter Herbivore Competition.

    Science.gov (United States)

    Pan, Huipeng; Preisser, Evan L; Su, Qi; Jiao, Xiaoguo; Xie, Wen; Wang, Shaoli; Wu, Qingjun; Zhang, Youjun

    2016-01-01

    Interspecific competition between herbivores is widely recognized as an important determinant of community structure. Although researchers have identified a number of factors capable of altering competitive interactions, few studies have addressed the influence of neighboring plant species. If adaptation to/ epigenetic effects of an herbivore's natal host plant alter its performance on other host plants, then interspecific herbivore interactions may play out differently in heterogeneous and homogenous plant communities. We tested wether the natal host plant of a whitefly population affected interactions between the Middle-east Asia Minor 1 (MEAM1) and Mediterranean (MED) cryptic species of the whitefly Bemisia tabaci by rearing the offspring of a cabbage-derived MEAM1 population and a poinsettia-derived MED population together on three different host plants: cotton, poinsettia, and cabbage. We found that MED dominated on poinsettia and that MEAM1 dominated on cabbage, results consistent with previous research. MED also dominated when reared with MEAM1 on cotton, however, a result at odds with multiple otherwise-similar studies that reared both species on the same natal plant. Our work provides evidence that natal plants affect competitive interactions on another plant species, and highlights the potential importance of neighboring plant species on herbivore community composition in agricultral systems.

  3. 9 CFR 93.104 - Certificate for pet birds, commercial birds, zoological birds, and research birds.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Certificate for pet birds, commercial birds, zoological birds, and research birds. 93.104 Section 93.104 Animals and Animal Products ANIMAL... (INCLUDING POULTRY) AND ANIMAL PRODUCTS IMPORTATION OF CERTAIN ANIMALS, BIRDS, FISH, AND POULTRY, AND CERTAIN...

  4. New perspectives on Natal Pulses from satellite observations

    CSIR Research Space (South Africa)

    Rouault, MJ

    2011-07-01

    Full Text Available that on their journey from the Natal Bight to Port Elizabeth, Natal Pulses systematically interact with the coastal topography to generate upstream perturbations. These upstream offshore meanders occur when the trailing edge of the original Natal Figure 2. SST daily... SST which have a relatively low tem- poral resolution (daily) can also prove difficult due to the extensive and persistent cloud coverage above the Agulhas Current [Rouault et al., 2000]. [5] High�frequency data acquisitions from the geostation...

  5. Ante-natal ionising radiation and cancer

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    This editorial comments on the latest reports of the Oxford Survey of Childhood Cancer (now based on Birmingham). With 14759 pairs, the latest survey is over 10-fold larger than the 1958 report and the calculation of fatal childhood cancer rate at one case in 990 ante-natal radiographic examinations is rather larger than the early estimates, in spite of the fetal radiation dose having been halved and the cure rate for childhood leukemia being much improved. Comments are made on the comparisons with bomb survivors, and on the much increased fatal cancer incidence after first trimester radiography. (UK)

  6. Long-distance Dispersal Patterns of Male Cerulean Warblers (Dendroica cerulea Measured by Stable-hydrogen Isotopes

    Directory of Open Access Journals (Sweden)

    M. Katherine. Girvan

    2007-12-01

    Full Text Available Despite the fundamental role played by long-distance dispersal in population dynamics, the mechanisms promoting or inhibiting dispersal by migratory songbirds are poorly understood. We used stable-hydrogen isotopes (δD to evaluate several hypotheses related to long-distance dispersal in the Cerulean Warbler (Dendroica cerulea, a migratory songbird at the center of considerable conservation attention. Feather samples were collected from 103 males throughout the breeding range. We assumed feathers were molted in late summer on the breeding grounds and thus δD values provided an estimate of breeding or hatching location for the previous year. We used a likelihood-based assignment test to estimate the origin of birds the previous year and derived expected δD values for the entire Cerulean Warbler breeding range from precipitation-based maps. Using Bayes' Rule, we also incorporated a prior probability of breeding origin based on estimated rates of site fidelity and survival between breeding seasons. We found that long-distance breeding dispersal by adult male Cerulean Warblers was a fairly common occurrence with 20 of 71 (28.2% individuals originating from a region other than the one they were sampled in. Surprisingly, long-distance natal dispersal was uncommon; only three of 32 (9.4% second-year birds were estimated to have hatched in a region outside their capture region. Young males may be using a form of post-fledging prospecting or conspecific attraction when selecting their first breeding habitats. Populations on the breeding range periphery, such as Ontario and Tennessee, tended to receive fewer long-distance dispersers than did other regions but produced more dispersing individuals than did core regions, suggesting that these areas could act as important sources for other regions. The tendency of a region to produce dispersing individuals was not significantly related to its relative abundance, implying that population abundance is not a

  7. Hyperolius argus (Anura) in Natal: taxonomy, biogeography and ...

    African Journals Online (AJOL)

    A high degree of variation in the colour pattern of. Hyperolius argus Peters, including sexual dichromatism and a marked cline, has led to much taxonomic confusion. This. East African species extends down the Natal coastal lowlands as far south as Durban. It has been assigned to. H. punctlculatus (Pfeffer) in Natal.

  8. cooperation and conflict – the british army, the natal government

    African Journals Online (AJOL)

    hennie

    invasion of Natal, stand on the punishment of high treason? Martial law had .... The offensive of the British Army in Natal and the immediate results thereof. On 11 May 1900, .... also to exercise its authority and independence. In addition to the ...

  9. Development of a tool for dispelling myths associated with natal ...

    African Journals Online (AJOL)

    Studies have revealed that Nigerians irrespective of social class have negative attitudes and practices towards children born with natal teeth and those who erupt teeth within the first 30 days of life. This has been associated with the strong cultural myths and beliefs that exist among the populace. Children with natal teeth ...

  10. Natal teeth in an infant with congenital hypothyroidism

    Directory of Open Access Journals (Sweden)

    C Venkatesh

    2011-01-01

    Full Text Available Teeth erupting at birth are referred to as natal teeth. It is a common and benign finding in the neonatal period. However, they may be associated with genetic syndromes like Ellis Van Creveld syndrome and Hallermann-Streiff syndrome. We report here a case of natal teeth in an infant with congenital hypothyroidism.

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

    Science.gov (United States)

    Aaron B. Shiels; Lawrence R. Walker

    2003-01-01

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

  12. Sex-specific effects of the local social environment on juvenile post-fledging dispersal in great tits

    NARCIS (Netherlands)

    Michler, Stephanie P. M.; Nicolaus, Marion; Ubels, Richard; van der Velde, Marco; Komdeur, Jan; Both, Christiaan; Tinbergen, Joost M.; Gibson, R.

    2011-01-01

    An individual's decision to disperse from the natal habitat can affect its future fitness prospects. Especially in species with sex-biased dispersal, we expect the cost benefit balance for dispersal to vary according to the social environment (e.g., local sex ratio and density). However, little is

  13. Drug metabolism in birds

    Science.gov (United States)

    Pan, Huo Ping; Fouts, James R.

    1979-01-01

    Papers published over 100 years since the beginning of the scientific study of drug metabolism in birds were reviewed. Birds were found to be able to accomplish more than 20 general biotransformation reactions in both functionalization and conjugation. Chickens were the primary subject of study but over 30 species of birds were used. Large species differences in drug metabolism exist between birds and mammals as well as between various birds, these differences were mostly quantitative. Qualitative differences were rare. On the whole, drug metabolism studies in birds have been neglected as compared with similar studies on insects and mammals. The uniqueness of birds and the advantages of using birds in drug metabolism studies are discussed. Possible future studies of drug metabolism in birds are recommended.

  14. Robert Plant (1818–1858: A Victorian plant hunter in Natal, Zululand, Mauritius and the Seychelles

    Directory of Open Access Journals (Sweden)

    Donal P. McCracken

    2011-03-01

    Full Text Available In the 1850s Robert William Plant collected plants and other natural specimens in what is now KwaZulu-Natal. This one-time Englishman compiled a dictionary for gardeners before emigrating to Natal in 1850. There he worked as the agent for Samuel Stevens, the London dealer in ‘curiosities of natural history’. Though Plant collected mainly plants, he also sent consignments of beetles, butterflies, bird skins and shells back to Britain. He published the first scientific paper on Zululand and was requested by the Royal Botanic Gardens at Kew to write the first Flora natalensis. It was while collecting for this never-to-be-completed treatise that Plant contracted malaria in Maputaland. He died in St Lucia in 1858 and in doing so became South Africa’s martyr to botany. What emerges from this study is a picture of the difficulties faced by plant hunters in mid-19th-century South Africa, the sort of plants they collected and the necessity for them sometimes to diversify into other natural history products to survive.

  15. Birth-Weight, Pregnancy Term, Pre-Natal and Natal Complications Related to Child's Dental Anomalies.

    Science.gov (United States)

    Prokocimer, T; Amir, E; Blumer, S; Peretz, B

    2015-01-01

    This cross-sectional study was aimed at determining whether certain pre-natal and natal conditions can predict specific dental anomalies. The conditions observed were: low birth-weight, preterm birth, pre-natal & natal complications. The dental anomalies observed were: enamel defects, total number of decayed, missing and filled teeth (total DMFT), disturbances in the tooth shape and disturbances in the number of teeth. Out of more than 2000 medical files of children aged 2-17 years old which were reviewed, 300 files met the selection criteria. Information recorded from the files included: age, gender, health status (the ASA physical status classification system by the American Society of Anesthesiologists), birth week, birth weight, total DMFT, hypomineralization, abnormal tooth shape, abnormal number of teeth and hypoplasia. Twenty one children out of 300 (7%) were born after a high-risk pregnancy, 25 children (8.3%) were born after high-risk birth, 20 children (6.7%) were born preterm - before week 37, and 29 children (9.7%) were born with a low birth weight (LBW) - 2500 grams or less. A relationship between a preterm birth and LBW to hypomineralization was found. And a relationship between a preterm birth and high-risk pregnancy to abnormal number of teeth was found. No relationship was found between birth (normal/high-risk) and the other parameters inspected. Preterm birth and LBW may predict hypomineralization in both primary and permanent dentitions. Furthermore, the study demonstrated that preterm birth and high-risk pregnancy may predict abnormal number of teeth in both dentitions.

  16. Juvenile dispersal in Calomys venustus (Muridae: Sigmodontinae)

    Science.gov (United States)

    Priotto, José; Steinmann, Andrea; Provensal, Cecilia; Polop, Jaime

    2004-05-01

    Both spacing behaviour and dispersal movement are viewed as hierarchical processes in which the effects may be expressed at spatial scale. This research was carried out to examine the hypothesis that the presence of parents promotes the dispersal of juveniles from their natal nest and their father or mother home-range, in Calomys venustus.The study was carried out in four 0.25 ha fences (two controls and two experimentals), in a natural pasture. This study had two periods: Father Removal (FR) (August and December 1997; year one) and Mother Removal (MR) (August 1998 and January 1999; year two). For the FR treatment fathers were removed after juveniles were born, but in the MR treatment mothers were removed after the juveniles were weaned. The effect of parents on the dispersal distance of juveniles was analysed with respect to their natal nest and their mother and father home-range. Dispersal distance from the nest of C. venustus was independent of either male or female parent. Juveniles were more dispersing in relation to the centre of activity of their mothers than to that of their fathers, and females were more dispersing than males. Female juveniles overlap their home-range with their parents less than male juveniles do. The differences observed between female and male juveniles would be related to their different sexual maturation times, as well as to the female territoriality.

  17. Wandering stars: age-related habitat use and dispersal of Javan Hawk-eagles (Spizaetus bartelsi)

    NARCIS (Netherlands)

    Nijman, V.; Balen, van S.

    2003-01-01

    Natal dispersal and philopatry have rarely been studied in tropical forest raptors. Especially with respect to endangered species with fragmented distributions more knowledge of dispersal and age-related habitat preferences is needed for proper management. We conducted an island-wide study on

  18. Age-dependent dispersal and habitat choice in black-tailed godwits

    NARCIS (Netherlands)

    Kentie, R.; Both, C.; Hooijmeijer, J.W.E.W.; Piersma, T.

    2014-01-01

    Whether to disperse, and where to, are two of the most prominent decisions in an individual's life, with major consequences for reproductive success. We studied natal and breeding dispersal in the monogamous black-tailed godwit Limosa limosa limosa in the Netherlands, where they breed in

  19. Birds and music

    Directory of Open Access Journals (Sweden)

    L Amini

    2009-03-01

    Through research in old mythological narrations, and literary texts, one could assume an intrinsic relationship between music and such sweet-singing mythological birds as phoenix, sphinx, Song-song, holy birds like Kership-tah, and other birds including swan and ring dove.

  20. Birds Kept as Pets

    Science.gov (United States)

    ... your pet’s health Visit a veterinarian who has experience with pet birds for routine check-ups to keep your bird healthy and prevent infectious diseases. If your bird becomes sick or dies within a month after purchase or adoption: Contact your veterinarian. Inform the pet ...

  1. Audubon Bird Study Program.

    Science.gov (United States)

    National Audubon Society, New York, NY.

    Included are a student reader, "The Story of Birds," a leaders' guide, a large colored Audubon bird chart, and a separate guide for the chart. The student reader is divided into eleven sections which relate to the various physical and behavioral features of birds such as feathers, feeding habits as related to the shape of bills and feet, nests,…

  2. Good reasons to leave home: proximate dispersal cues in a social spider.

    Science.gov (United States)

    Berger-Tal, Reut; Berner-Aharon, Na'ama; Aharon, Shlomi; Tuni, Cristina; Lubin, Yael

    2016-07-01

    Natal dispersal is a successful tactic under a range of conditions in spite of significant costs. Habitat quality is a frequent proximate cause of dispersal, and studies have shown that dispersal increases both when natal habitat quality is good or poor. In social species kin competition, favouring dispersal may be balanced by the benefits of group living, favouring philopatry. We investigated the effect of changes in the local environment on natal dispersal of adult females in a social spider species, Stegodyphus dumicola (Araneae, Eresidae), with a flexible breeding system, where females can breed either within the colony or individually following dispersal. We manipulated foraging opportunities in colonies by either removing the capture webs or by adding prey and recorded the number of dispersing females around each focal colony, and their survival and reproductive success. We predicted that increasing kin competition should increase dispersal of less-competitive individuals, while reducing competition could cause either less dispersal (less competition) or more dispersal (a cue indicating better chances to establish a new colony). Dispersal occurred earlier and at a higher rate in both food-augmented and web-removal colonies than in control colonies. Fewer dispersing females survived and reproduced in the web-removal group than in the control or food-augmented groups. The results support our prediction that worsening conditions in web-removal colonies favour dispersal, whereby increased kin competition and increased energy expenditure on web renewal cause females to leave the natal colony. By contrast, prey augmentation may serve as a habitat-quality cue; when the surrounding habitat is expected to be of high quality, females assess the potential benefit of establishing a new colony to be greater than the costs of dispersal. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

  3. Multiple origins of charnockite in the Mesoproterozoic Natal belt, Kwazulu-Natal, South Africa

    Directory of Open Access Journals (Sweden)

    G.H. Grantham

    2012-11-01

    Full Text Available Four different varieties of charnockitic rocks, with different modes of formation, from the Mesoproterozoic Natal belt are described and new C isotope data presented. Excellent coastal exposures in a number of quarries and river sections make this part of the Natal belt a good location for observing charnockitic field relationships. Whereas there has been much debate on genesis of charnockites and the use of the term charnockite, it is generally recognized that the stabilization of orthopyroxene relative to biotite in granitoid rocks is a function of low aH2O (± high CO2, high temperature, and composition (especially Fe/(Fe +Mg. From the Natal belt exposures, it is evident that syn-emplacement, magmatic crystallization of charnockite can arise from mantle-derived differentiated melts that are inherently hot and dry (as in the Oribi Gorge granites and Munster enderbite, as well as from wet granitic melts that have been affected through interaction with dry country rock to produce localized charnockitic marginal facies in plutons (as in the Portobello Granite. Two varieties of post-emplacement sub-solidus charnockites are also evident. These include charnockitic aureoles developed in leucocratic, biotite, garnet granite adjacent to cross-cutting enderbitic veins that are attributed to metamorphic-metasomatic processes (as in the Nicholson's Point granite, a part of the Margate Granite Suite, as well as nebulous, patchy charnockitic veins in the Margate Granite that are attributed to anatectic metamorphic processes under low-aH2O fluid conditions during a metamorphic event. These varieties of charnockite show that the required physical conditions of their genesis can be achieved through a number of geological processes, providing some important implications for the classification of charnockites, and for the interpretation of charnockite genesis in areas where poor exposure obscures field relationships.

  4. Experiences of childbirth in Natal Indian women

    Directory of Open Access Journals (Sweden)

    H.B. Brookes

    1991-09-01

    Full Text Available Through fifteen in-depth case studies of primipara, Natal Indian women’s experiences of childbirth have been described Common problems were identified, including lack of a family support person throughout labour, lithotomy position for delivery, episiotomies and their sequelae, breast-feeding difficulties and lack of professional support in the early puerperium at home. Preparation for common medical interventions in labour, breast-feeding and parenting appeared inadequate. Pertinent sociocultural aspects have been identified. These include continuing family support and culturally prescribed behaviour pertaining most importantly to the early puerperium and affecting the maternal-neonatal dyad. In the early adaptation to motherhood informants continued their role as daughter or daughter-in-law and would only actively continue their role as wife later or at the end of the puerperium. These traditional patterns of behaviour persist despite marked changes in educational level, language spoken and employment status. In the light of this research and founded on scientific evidence, a number of recommendations are made and areas for further research are identified

  5. National natality and fetal mortality surveys

    International Nuclear Information System (INIS)

    Roney, P.L.

    1980-01-01

    A project is described in which the Epidemiologic Studies Branch, DBE, is cooperating with the National Center for Health Statistics in a National Natality Survey and a National Fetal Mortality Survey of a sample of live births and of late fetal deaths (28 or more weeks gestation) in 1979. Questionnaires will be sent to a sample of mothers who had a live born infant or late fetal death in 1979, to hospitals in which the deliveries took place, to attending physicians, and all other possible sources of health care. The survey will provide quantitative information regarding use of ionizing and nonionizing radiation, including ultrasound, during pregnancy and possible associations between radiation and late fetal mortality. Specifically the study will provide information on the demographic and socioeconomic characteristics of the mothers and complications of pregnancy, labor, and delivery. The physical condition of the infant at birth is also included. This is one of many health surveys conducted routinely by the NCHS under the National Health Survey program

  6. Predictable evolution toward flightlessness in volant island birds.

    Science.gov (United States)

    Wright, Natalie A; Steadman, David W; Witt, Christopher C

    2016-04-26

    Birds are prolific colonists of islands, where they readily evolve distinct forms. Identifying predictable, directional patterns of evolutionary change in island birds, however, has proved challenging. The "island rule" predicts that island species evolve toward intermediate sizes, but its general applicability to birds is questionable. However, convergent evolution has clearly occurred in the island bird lineages that have undergone transitions to secondary flightlessness, a process involving drastic reduction of the flight muscles and enlargement of the hindlimbs. Here, we investigated whether volant island bird populations tend to change shape in a way that converges subtly on the flightless form. We found that island bird species have evolved smaller flight muscles than their continental relatives. Furthermore, in 366 populations of Caribbean and Pacific birds, smaller flight muscles and longer legs evolved in response to increasing insularity and, strikingly, the scarcity of avian and mammalian predators. On smaller islands with fewer predators, birds exhibited shifts in investment from forelimbs to hindlimbs that were qualitatively similar to anatomical rearrangements observed in flightless birds. These findings suggest that island bird populations tend to evolve on a trajectory toward flightlessness, even if most remain volant. This pattern was consistent across nine families and four orders that vary in lifestyle, foraging behavior, flight style, and body size. These predictable shifts in avian morphology may reduce the physical capacity for escape via flight and diminish the potential for small-island taxa to diversify via dispersal.

  7. North Slope, Alaska ESI: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for diving birds, gulls and terns, seabirds, shorebirds, and waterfowl for the North Slope of Alaska....

  8. Birds of Sabaki Birds of Sabaki

    African Journals Online (AJOL)

    CJ

    2005-02-25

    Feb 25, 2005 ... covers approximately 250ha.The area encompassed by this study extends from Mambrui to the north, the sea to the east, the opposite bank of the estuary to the south and the Sabaki bridge and Malindi-Garsen road to the west. The area is defined as an Important Bird Area(IBA) by BirdLife International in ...

  9. Post-fledging dispersal of king penguins (Aptenodytes patagonicus from two breeding sites in the South Atlantic.

    Directory of Open Access Journals (Sweden)

    Klemens Pütz

    Full Text Available Most studies concerning the foraging ecology of marine vertebrates are limited to breeding adults, although other life history stages might comprise half the total population. For penguins, little is known about juvenile dispersal, a period when individuals may be susceptible to increased mortality given their naïve foraging behaviour. Therefore, we used satellite telemetry to study king penguin fledglings (n = 18 from two sites in the Southwest Atlantic in December 2007. The two sites differed with respect to climate and proximity to the Antarctic Polar Front (APF, a key oceanographic feature generally thought to be important for king penguin foraging success. Accordingly, birds from both sites foraged predominantly in the vicinity of the APF. Eight king penguins were tracked for periods greater than 120 days; seven of these (three from the Falkland Islands and four from South Georgia migrated into the Pacific. Only one bird from the Falkland Islands moved into the Indian Ocean, visiting the northern limit of the winter pack-ice. Three others from the Falkland Islands migrated to the eastern coast of Tierra del Fuego before travelling south. Derived tracking parameters describing their migratory behaviour showed no significant differences between sites. Nevertheless, generalized linear habitat modelling revealed that juveniles from the Falkland Islands spent more time in comparatively shallow waters with low sea surface temperature, sea surface height and chlorophyll variability. Birds from South Georgia spent more time in deeper waters with low sea surface temperature and sea surface height, but high concentrations of chlorophyll. Our results indicate that inexperienced king penguins, irrespective of the location of their natal site in relation to the position of the APF, develop their foraging skills progressively over time, including specific adaptations to the environment around their prospective breeding site.

  10. Post-fledging dispersal of king penguins (Aptenodytes patagonicus) from two breeding sites in the South Atlantic.

    Science.gov (United States)

    Pütz, Klemens; Trathan, Phil N; Pedrana, Julieta; Collins, Martin A; Poncet, Sally; Lüthi, Benno

    2014-01-01

    Most studies concerning the foraging ecology of marine vertebrates are limited to breeding adults, although other life history stages might comprise half the total population. For penguins, little is known about juvenile dispersal, a period when individuals may be susceptible to increased mortality given their naïve foraging behaviour. Therefore, we used satellite telemetry to study king penguin fledglings (n = 18) from two sites in the Southwest Atlantic in December 2007. The two sites differed with respect to climate and proximity to the Antarctic Polar Front (APF), a key oceanographic feature generally thought to be important for king penguin foraging success. Accordingly, birds from both sites foraged predominantly in the vicinity of the APF. Eight king penguins were tracked for periods greater than 120 days; seven of these (three from the Falkland Islands and four from South Georgia) migrated into the Pacific. Only one bird from the Falkland Islands moved into the Indian Ocean, visiting the northern limit of the winter pack-ice. Three others from the Falkland Islands migrated to the eastern coast of Tierra del Fuego before travelling south. Derived tracking parameters describing their migratory behaviour showed no significant differences between sites. Nevertheless, generalized linear habitat modelling revealed that juveniles from the Falkland Islands spent more time in comparatively shallow waters with low sea surface temperature, sea surface height and chlorophyll variability. Birds from South Georgia spent more time in deeper waters with low sea surface temperature and sea surface height, but high concentrations of chlorophyll. Our results indicate that inexperienced king penguins, irrespective of the location of their natal site in relation to the position of the APF, develop their foraging skills progressively over time, including specific adaptations to the environment around their prospective breeding site.

  11. O papel das aves na dispersão e germinação de sementes do pau-incenso (Pittoporum undulatum Vent. em um remanescente de Mata Atlântica. Bird role in seed dispersion and germination of Pittosporum undulatum Vent., seeds in an Atlantic Forest remnant.

    Directory of Open Access Journals (Sweden)

    Mariana Lopes CAMPAGNOLI

    2016-06-01

    Full Text Available A invasão biológica pela espécie Pittosporum undulatum Vent. pode ocasionar degradação de ecossistemas nativos, perda de espécies e de serviços ecossistêmicos. Além das características biológicas que favorecem seu estabelecimento, seus frutos são fontes alimentares para algumas espécies de aves, que acabam por dispersar suas sementes. O presente estudo foi realizado no Parque Estadual Alberto Löfgren, e visou verificar as espécies de aves potencialmente dispersoras do pau-incenso, comparar os registros de alimentação obtidos para esta árvore e para outras seis espécies arbóreas locais e avaliar a influência da ingestão das sementes pelas aves na sua taxa de germinação. A coleta de dados consistiu em observações focais das aves em atividade de forrageio no pau-incenso e a captura de indivíduos com redes de neblina para coleta de sementes nas fezes. Testes de germinação foram realizados com as sementes coletadas das fezes e diretamente dos frutos maduros. No total, foram encontradas 107 sementes nas fezes de oito sabiás, pertencentes a três espécies: Turdus rufiventris, Turdus amaurochalinus e Turdus albicollis. Não encontramos diferenças significativas nas taxas de germinação entre os tratamentos. Apesar da passagem das sementes pelo trato digestório das aves não ter alterado significativamente as taxas de germinação, os sabiás podem ser importantes dispersores do pau-incenso, permitindo a colonização de novas áreas por esta espécie exótica e intensificando seu processo de invasão biológica na Mata Atlântica.Biological invasion by the species Pittosporum undulatum Vent. could bring degradation to native ecosystems and loss of biodiversity and ecological services. Besides the biological features favoring the establishment of the species in natural environments, some bird species use its fruits as food sources, being responsible for its seed dispersion. The present study was held at Alberto L

  12. forest birds in the Ongoye Forest Reserve, KwaZulu-Natal

    African Journals Online (AJOL)

    1997-02-03

    Feb 3, 1997 ... Amazonian Peru to support the edge-effect principle. By choosing a large forest and ... rodents, anurans; see Laurance 1990) is overdue. We also agree with .... Edge and other effects of isolation on Amazon forest fragments.

  13. Locomotion during digestion changes current estimates of seed dispersal kernels by fish

    NARCIS (Netherlands)

    van Leeuwen, Casper H.A.; Beukeboom, Rosanne; Nolet, Bart A.; Bakker, Elisabeth S.; Pollux, Bart J.A.

    2016-01-01

    Dispersal of seeds by animals is an important mechanism regulating plant diversity, range expansions and invasions. Many birds, mammals, fish, and reptiles regularly ingest, transport and excrete viable seeds (known as endozoochory). The effectiveness of endozoochory is modelled in dispersal

  14. Diseases Transmitted by Birds.

    Science.gov (United States)

    Levison, Matthew E

    2015-08-01

    Although many people these days actually work very hard at leisure time activities, diseases are most commonly acquired from birds during the course of work in the usual sense of the term, not leisure. However, travel for pleasure to areas where the diseases are highly endemic puts people at risk of acquiring some of these bird-related diseases (for example, histoplasmosis and arbovirus infections), as does ownership of birds as pets (psittacosis).

  15. Coastal Resources Atlas: Long Island: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, raptors, diving birds, seabirds, passerine birds, and gulls and...

  16. Guam and the Northern Mariana Islands ESI: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for pelagic birds, shorebirds, wading birds, waterfowl, gulls, terns, and passerine birds in Guam and the...

  17. Assistência pré-natal no Brasil

    Directory of Open Access Journals (Sweden)

    Elaine Fernandes Viellas

    2014-08-01

    Full Text Available O estudo tem por objetivo analisar a assistência pré-natal oferecida às gestantes usuárias de serviços de saúde públicos e/ou privados utilizando dados da pesquisa Nascer no Brasil, realizada em 2011 e 2012. As informações foram obtidas por meio de entrevista com a puérpera durante a internação hospitalar e dados do cartão de pré- natal. Os resultados mostram cobertura elevada da assistência pré-natal (98,7% tendo 75,8% das mulheres iniciado o pré-natal antes da 16a semana gestacional e 73,1% compareceram a seis ou mais consultas. O pré-natal foi realizado, sobretudo, em unidades básicas (89,6%, públicas (74,6%, pelo mesmo profissional (88,4%, em sua maioria médicos (75,6%, e 96% receberam o cartão de pré-natal. Um quarto das gestantes foi considerado de risco. Do total das entrevistadas, apenas 58,7% foram orientadas sobre a maternidade de referência, e 16,2% procuraram mais de um serviço para a admissão para o parto. Desafios persistem para a melhoria da qualidade dessa assistência, com a realização de procedimentos efetivos para a redução de desfechos desfavoráveis.

  18. Bird Flu (Avian Influenza)

    Science.gov (United States)

    Bird flu (avian influenza) Overview Bird flu is caused by a type of influenza virus that rarely infects humans. More than a ... for Disease Control and Prevention estimates that seasonal influenza is responsible for ... heat destroys avian viruses, cooked poultry isn't a health threat. ...

  19. Nanoscale magnetoreceptors in birds

    DEFF Research Database (Denmark)

    Solov'yov, Ilia; Greiner, Walter

    2012-01-01

    The Earth's magnetic field provides an important source of directional information for many living organisms, especially birds, but the sensory receptor responsible for magnetic field detection still has to be identified. Recently, magnetic iron oxide particles were detected in dendritic endings...... field, by a bird....

  20. Understanding how birds navigate

    DEFF Research Database (Denmark)

    Solov'yov, Ilia; Schulten, Klaus

    2009-01-01

    A proposed model for migrating birds' magnetic sense can withstand moderate orientational disorder of a key protein in the eye.......A proposed model for migrating birds' magnetic sense can withstand moderate orientational disorder of a key protein in the eye....

  1. Kajian Panjang Jalan di Kabupaten Mandailing Natal dan Pengaruhnya Terhadap Perkembangan Wilayah

    OpenAIRE

    Lubis, Indra Husein

    2010-01-01

    Dengan terbitnya Undang-undang Republik Indonesia Nomor 12 tahun 1998 dan disahkan pada tanggal 23 Nopember 1998 tentang pembentukan Kabupaten Mandailing Natal maka Kabupaten Tapanuli Selatan dimekarkan menjadi 2 Kabupaten, yaitu Kabupaten Mandailing Natal (Ibukota Panyabungan) dengan jumlah daerah Administrasi 8 Kecamatan dan Kabupaten Tapanuli Selatan (Ibukotanya Padangsidimpuan) dengan jumlah daerah administrasi 16 Kecamatan. Perkembangan pembangunan kabupaten Mandailing Natal selama ± 11 ...

  2. Hydrodynamic disperser

    Energy Technology Data Exchange (ETDEWEB)

    Bulatov, A.I.; Chernov, V.S.; Prokopov, L.I.; Proselkov, Yu.M.; Tikhonov, Yu.P.

    1980-01-15

    A hydrodynamic disperser is suggested which contains a housing, slit nozzles installed on a circular base arranged opposite from each other, resonators secured opposite the nozzle and outlet sleeve. In order to improve the effectiveness of dispersion by throttling the flow, each resonator is made in the form of a crimped plate with crimpings that decrease in height in a direction towards the nozzle.

  3. Great cormorants reveal overlooked secondary dispersal of plants and invertebrates by piscivorous waterbirds

    NARCIS (Netherlands)

    van Leeuwen, C.H.A.; Lovas-Kiss, A.; Ovegård, M.; Green, Andy J.

    2017-01-01

    In wetland ecosystems, birds and fish are important dispersal vectors for plants and invertebrates, but the consequences of their interactions as vectors are unknown. Darwin suggested that piscivorous birds carry out secondary dispersal of seeds and invertebrates via predation on fish. We tested

  4. Activity rhythms and distribution of natal dens for red foxes

    Science.gov (United States)

    Wenyang, Zhou; Wanhong, Wei; Biggins, Dean E.

    1995-01-01

    The red fox, Vulpes vulpes, was investigated with snow tracking, radiotracking and directive observation at the Haibei Research Station of Alpine Meadow Ecosystem, Academia Sinica, from March to September 1994. The objectives of this study were to determine the distribution and use of natal dens, activity rhythms, and home range sizes for the foxes.

  5. Magnetospheric and atmospheric physics at the University of Natal

    International Nuclear Information System (INIS)

    Walker, A.D.M.

    1982-01-01

    A historical outline of geophysical work done at the University of Natal from 1938-1982 is given. Mention is also made of experimental work concerning whistlers and VLF, low-light level TV and geomagnetic pulsations. Current work on the magnetosphere, namely plasma convection in plasmasphere, auroral features, geomagnetic pulsations and the measuring of plasma properties is discussed

  6. Marine research in Natal: proceedings of a symposium and workshop

    CSIR Research Space (South Africa)

    Bowmaker, AP

    1987-01-01

    Full Text Available A two day mini-symposium and workshop held in Durban in February 1986 and attended by 70 marine scientists from Natal and KwaZulu is reported on. Summaries of 84 presentations are given, separated into relevant sections. Each section is summarized...

  7. Safety and Security in Schools in KwaZulu-Natal

    Science.gov (United States)

    White, C. J.; Gina, J. M.; Coetzee, I. E. M.

    2015-01-01

    This article is based on research conducted on the topic: "Safety and security in schools: The case of KwaZulu-Natal." For the research project a purposive sample consisting of secondary school learners, teachers, school governing body chairpersons and principals were selected from the rural and township schools used in this study to…

  8. ORIGINAL ARTICLES Severe snakebites in northern KwaZulu-Natal ...

    African Journals Online (AJOL)

    ... in north-eastern KwaZulu-Natal. Ngwelezana Hospital is a 500-bed hospital situated in a semi- ... delayed by up to 7 - 12 days.5,7 Test dosing with antivenom is no longer ... highest incidence was in the summer months; 46 (18.93%) patients ...

  9. Hyperolius argus (Anura) in Natal: taxonomy, biogeography and ...

    African Journals Online (AJOL)

    There is some evidence that populations of argus intergrade with semidiscus Hewitt in Natal, and the occurrence of semidiscus on the periphery of the argusrange is discussed in relation to the 'central-marginal' model of biogeographical patterning. It has not been possible to determine the relative vulnerability to habitat ...

  10. FUNCTIONALLY UNIVENTRICULAR HEARTS: IMPACT OF PRE-NATAL DIAGNOSIS

    Directory of Open Access Journals (Sweden)

    Antonio Francesco Corno

    2015-02-01

    Full Text Available Within the last few decades the pre-natal echocardiographic diagnosis of congenital heart defects has made substantial progresses, particularly for the identification of complex malformation. Functionally univentricular hearts categorize a huge variety of heart malformations. Since no one of the patients with these congenital heart defects can ever undergo a bi-ventricular type of repair, early recognition and decision-making from the neonatal period are required in order to allow for appropriate multiple-step diagnostic and treatment procedures, either of interventional cardiology and/or surgery, on the pathway of univentricular heart. In the literature strong disagreements exist about the potential impact of the pre-natal diagnosis on the early and late outcomes of complex congenital heart defects. This review of the recent reports has been undertaken to better understand the impact of pre-natal diagnosis in functionally univentricular hearts taking into consideration the following topics:•pre-natal screening•outcomes and survival•general morbidity•neurologic and developmental consequences•pregnancy management and delivery planning•resources utilization and costs/benefits issues•ethical implications, parents counseling, interruption of pregnancy versus treatment

  11. Educational Leadership with an Ethics of Plurality and Natality

    Science.gov (United States)

    Berger, Iris

    2015-01-01

    This paper aims to impregnate the concept of educational leadership with new meanings and new possibilities. I draw on Hannah Arendt's ("The human condition." University of Chicago Press, Chicago, 1958/1998) political thought, particularly, her concepts of "plurality" and "natality" alongside the distinction she made…

  12. Ecosystem considerations of the KwaZulu-Natal sardine run ...

    African Journals Online (AJOL)

    The annual winter sardine run along the South African east coast impacts the KwaZulu-Natal (KZN) coastal system in a variety of ways. These include ecological impacts, such as enrichment of a largely oligotrophic environment, competition between migrant sardine Sardinops sagax, other migrant and resident small ...

  13. Fertilization of Southern Tall Grassveld of Natal: effects on botanical ...

    African Journals Online (AJOL)

    The long-term effects of nitrogen, phosphate and lime on change in botanical composition and utilisation under grazing of Southern Tall Grassveld of Natal are presented. Nitrogen, phosphate, lime and type of nitrogen affected botanical composition significantly. Generally, fertilisation had the same effect on species ...

  14. Roles of birds and bats in early tropical-forest restoration.

    Science.gov (United States)

    de la Peña-Domene, Marinés; Martínez-Garza, Cristina; Palmas-Pérez, Sebastián; Rivas-Alonso, Edith; Howe, Henry F

    2014-01-01

    Restoration of tropical forest depended in large part on seed dispersal by fruit-eating animals that transported seeds into planted forest patches. We tested effectiveness of dispersal agents as revealed by established recruits of tree and shrub species that bore seeds dispersed by birds, bats, or both. We documented restoration of dispersal processes over the first 76 months of experimental restoration in southern Mexico. Mixed-model repeated-measures randomized-block ANOVAs of seedlings recruited into experimental controls and mixed-species plantings from late-secondary and mature forest indicated that bats and birds played different roles in the first years of a restoration process. Bats dispersed pioneer tree and shrub species to slowly regenerating grassy areas, while birds mediated recruitment of later-successional species into planted stands of trees and to a lesser extent into controls. Of species of pioneer trees and shrubs established in plots, seven were primarily dispersed by birds, three by bats and four by both birds and bats. Of later-successional species recruited past the seedling stage, 13 were of species primarily dispersed by birds, and six were of species dispersed by both birds and bats. No later-successional species primarily dispersed by bats established in control or planted plots. Establishment of recruited seedlings was ten-fold higher under cover of planted trees than in grassy controls. Even pre-reproductive trees drew fruit-eating birds and the seeds that they carried from nearby forest, and provided conditions for establishment of shade-tolerant tree species. Overall, after 76 months of cattle exclusion, 94% of the recruited shrubs and trees in experimental plots were of species that we did not plant.

  15. Roles of birds and bats in early tropical-forest restoration.

    Directory of Open Access Journals (Sweden)

    Marinés de la Peña-Domene

    Full Text Available Restoration of tropical forest depended in large part on seed dispersal by fruit-eating animals that transported seeds into planted forest patches. We tested effectiveness of dispersal agents as revealed by established recruits of tree and shrub species that bore seeds dispersed by birds, bats, or both. We documented restoration of dispersal processes over the first 76 months of experimental restoration in southern Mexico. Mixed-model repeated-measures randomized-block ANOVAs of seedlings recruited into experimental controls and mixed-species plantings from late-secondary and mature forest indicated that bats and birds played different roles in the first years of a restoration process. Bats dispersed pioneer tree and shrub species to slowly regenerating grassy areas, while birds mediated recruitment of later-successional species into planted stands of trees and to a lesser extent into controls. Of species of pioneer trees and shrubs established in plots, seven were primarily dispersed by birds, three by bats and four by both birds and bats. Of later-successional species recruited past the seedling stage, 13 were of species primarily dispersed by birds, and six were of species dispersed by both birds and bats. No later-successional species primarily dispersed by bats established in control or planted plots. Establishment of recruited seedlings was ten-fold higher under cover of planted trees than in grassy controls. Even pre-reproductive trees drew fruit-eating birds and the seeds that they carried from nearby forest, and provided conditions for establishment of shade-tolerant tree species. Overall, after 76 months of cattle exclusion, 94% of the recruited shrubs and trees in experimental plots were of species that we did not plant.

  16. Hatching synchrony in birds

    OpenAIRE

    Tippeltová, Zuzana

    2011-01-01

    This bachelor thesis is about hatching synchrony in birds. Generally, among birds there are two types of hatching - asynchronous and synchronous- and the type of hatching is primarily determined by the time of the onset of incubation. In many bird species, including most precocial ones, incubation does not begin until the last egg has been laid, which results in hatching of all the eggs within a few hours. In synchronously-hatched broods, all the chicks are about the same age. Thus no single ...

  17. Dispersion Forces

    CERN Document Server

    Buhmann, Stefan Yoshi

    2012-01-01

    In this book, a modern unified theory of dispersion forces on atoms and bodies is presented which covers a broad range of advanced aspects and scenarios. Macroscopic quantum electrodynamics is shown to provide a powerful framework for dispersion forces which allows for discussing general properties like their non-additivity and the relation between microscopic and macroscopic interactions. It is demonstrated how the general results can be used to obtain dispersion forces on atoms in the presence of bodies of various shapes and materials. Starting with a brief recapitulation of volume I, this volume II deals especially with bodies of irregular shapes, universal scaling laws, dynamical forces on excited atoms, enhanced forces in cavity quantum electrodynamics, non-equilibrium forces in thermal environments and quantum friction. The book gives both the specialist and those new to the field a thorough overview over recent results in the field. It provides a toolbox for studying dispersion forces in various contex...

  18. Barrier Infrared Detector (BIRD)

    Data.gov (United States)

    National Aeronautics and Space Administration — A recent breakthrough in MWIR detector design, has resulted in a high operating temperature (HOT) barrier infrared detector (BIRD) that is capable of spectral...

  19. Calcium metabolism in birds.

    Science.gov (United States)

    de Matos, Ricardo

    2008-01-01

    Calcium is one of the most important plasma constituents in mammals and birds. It provides structural strength and support (bones and eggshell) and plays vital roles in many of the biochemical reactions in the body. The control of calcium metabolism in birds is highly efficient and closely regulated in a number of tissues, primarily parathyroid gland, intestine, kidney, and bone. The hormones with the greatest involvement in calcium regulation in birds are parathyroid hormone, 1,25-dihydroxyvitamin D(3) (calcitriol), and estrogen, with calcitonin playing a minor and uncertain role. The special characteristics of calcium metabolism in birds, mainly associated with egg production, are discussed, along with common clinical disorders secondary to derangements in calcium homeostasis.

  20. Birds as biodiversity surrogates

    DEFF Research Database (Denmark)

    Larsen, Frank Wugt; Bladt, Jesper Stentoft; Balmford, Andrew

    2012-01-01

    1. Most biodiversity is still unknown, and therefore, priority areas for conservation typically are identified based on the presence of surrogates, or indicator groups. Birds are commonly used as surrogates of biodiversity owing to the wide availability of relevant data and their broad popular...... and applications.?Good surrogates of biodiversity are necessary to help identify conservation areas that will be effective in preventing species extinctions. Birds perform fairly well as surrogates in cases where birds are relatively speciose, but overall effectiveness will be improved by adding additional data...... from other taxa, in particular from range-restricted species. Conservation solutions with focus on birds as biodiversity surrogate could therefore benefit from also incorporating species data from other taxa....

  1. Awesome Audubon Birds

    Science.gov (United States)

    Kahler, Laura

    2010-01-01

    In this article, the author describes a watercolor art lesson on Audubon birds. She also discusses how science, technology, writing skills, and the elements and principles of art can be incorporated into the lesson.

  2. Nuisance Birds Webinar Report

    Science.gov (United States)

    All over the nation, birds of all shapes and sizes attempt to make schools a their favorite hangout. Their arrival can lead to sanitation issues, added facility degradation, distracted students and health problems.

  3. Birds - Breeding [ds60

    Data.gov (United States)

    California Natural Resource Agency — This data set provides access to information gathered on annual breeding bird surveys in California using a map layer developed by the Department. This data layer...

  4. Breeding bird survey data

    Data.gov (United States)

    U.S. Environmental Protection Agency — The data are maintained by the USGS (https://www.pwrc.usgs.gov/bbs/RawData/) and provides information on the trends and status of North American bird populations...

  5. Consequences of pre-natal radiation exposure for post-natal development

    International Nuclear Information System (INIS)

    Mole, R.H.

    1982-01-01

    A review of revised observations on Japanese bomb survivors suggests that 10-18 weeks of pregnancy is the period of greatest sensitivity for foetal brain damage leading to severe mental retardation. Severe food deficiencies suggest a cause for the apparently high frequency of severe mental retardation in the unexposed control population and may also have contributed to the dose-dependent increase in those irradiated in utero. The author concludes that there is no confirmed evidence to suggest that the pre-implantation stage of mammalian development is unusually radiosensitive. In the human, the succeeding period of major organogenesis seems to be less sensitive and important than the following 10-18 week period of pregnancy. It is suggested that malformation (teratogenesis) should be distinguished from maldevelopment. Malformations are the result of failure of embryonic organization and ionizing radiation is not an efficient teratogen in this sense. Maldevelopment after exposure to radiation is the consequence of cell depletion of sufficient degree randomly distributed throughout an irradiated tissue. It is concluded that dose thresholds for maldevelopments are to be expected after irradiation both in pre-implantation and post-implantation stages, and that somatic mutation has a possible role as a mechanism without threshold for development damage by pre-natal irradiation, but not likely to be of practical significance. (U.K.)

  6. Seed-dispersal distributions by trumpeter hornbills in fragmented landscapes

    Science.gov (United States)

    Lenz, Johanna; Fiedler, Wolfgang; Caprano, Tanja; Friedrichs, Wolfgang; Gaese, Bernhard H.; Wikelski, Martin; Böhning-Gaese, Katrin

    2011-01-01

    Frugivorous birds provide important ecosystem services by transporting seeds of fleshy fruited plants. It has been assumed that seed-dispersal kernels generated by these animals are generally leptokurtic, resulting in little dispersal among habitat fragments. However, little is known about the seed-dispersal distribution generated by large frugivorous birds in fragmented landscapes. We investigated movement and seed-dispersal patterns of trumpeter hornbills (Bycanistes bucinator) in a fragmented landscape in South Africa. Novel GPS loggers provide high-quality location data without bias against recording long-distance movements. We found a very weakly bimodal seed-dispersal distribution with potential dispersal distances up to 14.5 km. Within forest, the seed-dispersal distribution was unimodal with an expected dispersal distance of 86 m. In the fragmented agricultural landscape, the distribution was strongly bimodal with peaks at 18 and 512 m. Our results demonstrate that seed-dispersal distributions differed when birds moved in different habitat types. Seed-dispersal distances in fragmented landscapes show that transport among habitat patches is more frequent than previously assumed, allowing plants to disperse among habitat patches and to track the changing climatic conditions. PMID:21177686

  7. A method for investigating population declines of migratory birds using stable isotopes: origins of harvested lesser scaup in North America.

    Directory of Open Access Journals (Sweden)

    Keith A Hobson

    2009-11-01

    Full Text Available Elucidating geographic locations from where migratory birds are recruited into adult breeding populations is a fundamental but largely elusive goal in conservation biology. This is especially true for species that breed in remote northern areas where field-based demographic assessments are logistically challenging.Here we used hydrogen isotopes (deltaD to determine natal origins of migrating hatch-year lesser scaup (Aythya affinis harvested by hunters in the United States from all North American flyways during the hunting seasons of 1999-2000 (n = 412 and 2000-2001 (n = 455. We combined geospatial, observational, and analytical data sources, including known scaup breeding range, deltaD values of feathers from juveniles at natal sites, models of deltaD for growing-season precipitation, and scaup band-recovery data to generate probabilistic natal origin landscapes for individual scaup. We then used Monte Carlo integration to model assignment uncertainty from among individual deltaD variance estimates from birds of known molt origin and also from band-return data summarized at the flyway level. We compared the distribution of scaup natal origin with the distribution of breeding population counts obtained from systematic long-term surveys.Our analysis revealed that the proportion of young scaup produced in the northern (above 60 degrees N versus the southern boreal and Prairie-Parkland region was inversely related to the proportions of breeding adults using these regions, suggesting that despite having a higher relative abundance of breeding adults, the northern boreal region was less productive for scaup recruitment into the harvest than more southern biomes. Our approach for evaluating population declines of migratory birds (particularly game birds synthesizes all available distributional data and exploits the advantages of intrinsic isotopic markers that link individuals to geography.

  8. Effects of alien woody plant invasion on the birds of Mountain ...

    African Journals Online (AJOL)

    1989-04-18

    Apr 18, 1989 ... alien A. cyclops is apparently enhanced by dispersal of the seeds by frugivorous birds (Glyphis, Milton & .... Friedman two-way analysis of variance by ranks (Con- over 1971) was used to assess the significance of ...... Towards a theory of continental species diversities: bird distributions over mediterranean ...

  9. Modeling birds on wires.

    Science.gov (United States)

    Aydoğdu, A; Frasca, P; D'Apice, C; Manzo, R; Thornton, J M; Gachomo, B; Wilson, T; Cheung, B; Tariq, U; Saidel, W; Piccoli, B

    2017-02-21

    In this paper we introduce a mathematical model to study the group dynamics of birds resting on wires. The model is agent-based and postulates attraction-repulsion forces between the interacting birds: the interactions are "topological", in the sense that they involve a given number of neighbors irrespective of their distance. The model is first mathematically analyzed and then simulated to study its main properties: we observe that the model predicts birds to be more widely spaced near the borders of each group. We compare the results from the model with experimental data, derived from the analysis of pictures of pigeons and starlings taken in New Jersey: two different image elaboration protocols allow us to establish a good agreement with the model and to quantify its main parameters. We also discuss the potential handedness of the birds, by analyzing the group organization features and the group dynamics at the arrival of new birds. Finally, we propose a more refined mathematical model that describes landing and departing birds by suitable stochastic processes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Measuring dispersal as distance-dependent recruitment rates: testing the performance of DDRR on simulated data.

    NARCIS (Netherlands)

    Van Noordwijk, A.J.

    2011-01-01

    Dispersal is an important process in ecology, but its measurement is difficult. In particular, natal dispersal— the net movement between site of birth and site of first reproduction—is important, since it determines population structure. Using simulated data, I study the claim that measuring

  11. A Phororhacoid bird from the Eocene of Africa

    Science.gov (United States)

    Mourer-Chauviré, Cécile; Tabuce, Rodolphe; Mahboubi, M'hammed; Adaci, Mohammed; Bensalah, Mustapha

    2011-10-01

    The bird fossil record is globally scarce in Africa. The early Tertiary evolution of terrestrial birds is virtually unknown in that continent. Here, we report on a femur of a large terrestrial new genus discovered from the early or early middle Eocene (between ˜52 and 46 Ma) of south-western Algeria. This femur shows all the morphological features of the Phororhacoidea, the so-called Terror Birds. Most of the phororhacoids were indeed large, or even gigantic, flightless predators or scavengers with no close modern analogs. It is likely that this extinct group originated in South America, where they are known from the late Paleocene to the late Pleistocene (˜59 to 0.01 Ma). The presence of a phororhacoid bird in Africa cannot be explained by a vicariant mechanism because these birds first appeared in South America well after the onset of the mid-Cretaceous Gondwana break up (˜100 million years old). Here, we propose two hypotheses to account for this occurrence, either an early dispersal of small members of this group, which were still able of a limited flight, or a transoceanic migration of flightless birds from South America to Africa during the Paleocene or earliest Eocene. Paleogeographic reconstructions of the South Atlantic Ocean suggest the existence of several islands of considerable size between South America and Africa during the early Tertiary, which could have helped a transatlantic dispersal of phororhacoids.

  12. Dispersal and migration

    Directory of Open Access Journals (Sweden)

    Schwarz, C.

    2004-06-01

    Full Text Available Ringing of birds unveiled many aspects of avian migration and dispersal movements. However, there is even much more to be explored by the use of ringing and other marks. Dispersal is crucial in understanding the initial phase of migration in migrating birds as it is to understand patterns and processes of distribution and gene flow. So far, the analysis of migration was largely based on analysing spatial and temporal patters of recoveries of ringed birds. However, there are considerable biases and pitfalls in using recoveries due to spatial and temporal variation in reporting probabilities. Novel methods are required for future studies separating the confounding effects of spatial and temporal heterogeneity of recovery data and heterogeneity of the landscape as well. These novel approaches should aim a more intensive and novel use of the existing recovery data by taking advantage of, for instance, dynamic and multistate modeling, should elaborate schemes for future studies, and should also include other marks that allow a more rapid data collection, like telemetry, geolocation and global positioning systems, and chemical and molecular markers. The latter appear to be very useful in the delineating origin of birds and connectivity between breeding and non–breeding grounds. Many studies of migration are purely descriptive. However, King and Brooks (King & Brooks, 2004 examine if movement patterns of dolphins change after the introduction of a gillnet ban. Bayesian methods are an interesting approach to this problem as they provide a meaningful measure of the probability that such a change occurred rather than simple yes/no response that is often the result of classical statistical methods. However, the key difficulty of a general implementation of Bayesian methods is the complexity of the modelling —there is no general userfriendly package that is easily accessible to most scientists. Drake and Alisauskas (Drake & Alisauskas, 2004 examine the

  13. Aerodynamics of bird flight

    Directory of Open Access Journals (Sweden)

    Dvořák Rudolf

    2016-01-01

    Full Text Available Unlike airplanes birds must have either flapping or oscillating wings (the hummingbird. Only such wings can produce both lift and thrust – two sine qua non attributes of flying.The bird wings have several possibilities how to obtain the same functions as airplane wings. All are realized by the system of flight feathers. Birds have also the capabilities of adjusting the shape of the wing according to what the immediate flight situation demands, as well as of responding almost immediately to conditions the flow environment dictates, such as wind gusts, object avoidance, target tracking, etc. In bird aerodynamics also the tail plays an important role. To fly, wings impart downward momentum to the surrounding air and obtain lift by reaction. How this is achieved under various flight situations (cruise flight, hovering, landing, etc., and what the role is of the wing-generated vortices in producing lift and thrust is discussed.The issue of studying bird flight experimentally from in vivo or in vitro experiments is also briefly discussed.

  14. Sex Reversal in Birds.

    Science.gov (United States)

    Major, Andrew T; Smith, Craig A

    2016-01-01

    Sexual differentiation in birds is controlled genetically as in mammals, although the sex chromosomes are different. Males have a ZZ sex chromosome constitution, while females are ZW. Gene(s) on the sex chromosomes must initiate gonadal sex differentiation during embryonic life, inducing paired testes in ZZ individuals and unilateral ovaries in ZW individuals. The traditional view of avian sexual differentiation aligns with that expounded for other vertebrates; upon sexual differentiation, the gonads secrete sex steroid hormones that masculinise or feminise the rest of the body. However, recent studies on naturally occurring or experimentally induced avian sex reversal suggest a significant role for direct genetic factors, in addition to sex hormones, in regulating sexual differentiation of the soma in birds. This review will provide an overview of sex determination in birds and both naturally and experimentally induced sex reversal, with emphasis on the key role of oestrogen. We then consider how recent studies on sex reversal and gynandromorphic birds (half male:half female) are shaping our understanding of sexual differentiation in avians and in vertebrates more broadly. Current evidence shows that sexual differentiation in birds is a mix of direct genetic and hormonal mechanisms. Perturbation of either of these components may lead to sex reversal. © 2016 S. Karger AG, Basel.

  15. Lack of pubertal influences on female dispersal in muriqui monkeys, Brachyteles arachnoides.

    Science.gov (United States)

    Strier; Ziegler

    2000-04-01

    The hormonal mediation of dispersal in female mammals is poorly understood, in part because of the difficulties of detecting the onset of ovarian cycling and puberty in dispersing individuals. We used noninvasive methods of faecal steroid assays to determine the timing of dispersal relative to puberty and ovarian cycling in wild female muriqui monkeys, a species in which males are philopatric and nearly all females transfer from their natal groups. Natal females had a mean+/-SE age of 73.4+/-7.2 months (N=18) at the time of their transfers. Intergroup transfers occurred when one or more sexually active adult females were present, but did not show any seasonal patterns. Faecal progesterone and oestradiol profiles from nine natal females prior to transfer and four non-natal females that transferred into our study group demonstrate unequivocally that dispersal occurs prior to puberty in this species. All females showed baseline oestradiol levels and low progesterone levels compared with cycling adult females. Immigrants were first observed to copulate at 11.2+/-2.2 months of age (N=4), prior to the onset of normal ovarian cycles, and gave birth to their first offspring at 33.8+/-7.3 months (N=4) after transferring. Mean cortisol levels did not differ between natal emigrants or recent immigrants, and were within the range of those of adult males during the nonbreeding season in 10 of the 11 prepubertal females sampled. These results indicate that female dispersal is not triggered by activational hormones associated with puberty or escape from reproductive suppression in this species. Copyright 2000 The Association for the Study of Animal Behaviour.

  16. Modern beachrock formation in Durban, KwaZulu-Natal

    OpenAIRE

    Hayley Cawthra; Ron Uken

    2012-01-01

    We explored the recent cementation of modern beachrock on the seaward margin of the Durban Bluff, central KwaZulu-Natal. The low latitude and subtropical climatic setting is a unique context compared to the more commonly documented contemporary beachrock formation in the tropics. Geological field mapping was carried out and here we present results based on sedimentary facies of a clastic shoreline and carbonate diagenesis of interstitial cements using transmitted light microscopy. The beachro...

  17. Aging in Birds.

    Science.gov (United States)

    Travin, D Y; Feniouk, B A

    2016-12-01

    Rodents are the most commonly used model organisms in studies of aging in vertebrates. However, there are species that may suit this role much better. Most birds (Aves), having higher rate of metabolism, live two-to-three times longer than mammals of the same size. This mini-review briefly covers several evolutionary, ecological, and physiological aspects that may contribute to the phenomenon of birds' longevity. The role of different molecular mechanisms known to take part in the process of aging according to various existing theories, e.g. telomere shortening, protection against reactive oxygen species, and formation of advanced glycation end-products is discussed. We also address some features of birds' aging that make this group unique and perspective model organisms in longevity studies.

  18. Chemical dispersants

    NARCIS (Netherlands)

    Rahsepar, Shokouhalsadat; Smit, Martijn P.J.; Murk, Albertinka J.; Rijnaarts, Huub H.M.; Langenhoff, Alette A.M.

    2016-01-01

    Chemical dispersants were used in response to the Deepwater Horizon oil spill in the Gulf of Mexico, both at the sea surface and the wellhead. Their effect on oil biodegradation is unclear, as studies showed both inhibition and enhancement. This study addresses the effect of Corexit on oil

  19. Cook Inlet and Kenai Peninsula, Alaska ESI: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for alcids, shorebirds, waterfowl, diving birds, pelagic birds, gulls and terns in Cook Inlet and Kenai Peninsula,...

  20. Wind power and bird kills

    International Nuclear Information System (INIS)

    Raynolds, M.

    1998-01-01

    The accidental killing of birds by wind generators, and design improvements in the towers that support the turbines that might cut down on the bird killings were discussed. The first problem for the industry began in the late 1980s when the California Energy Commission reported as many as 160 birds (the majority being raptors, including the protected golden eagle) killed in one year in the vicinity of wind power plants. The key factor identified was the design of the towers as birds of prey are attracted to lattice towers as a place to hunt from. Tubular towers do not provide a place for the birds to perch, therefore they reduce the potential for bird strikes. Bird strikes also have been reported in Spain and the siting of the towers have been considered as the principal cause of the bird strikes. In view of these incidents, the wind power industry is developing standards for studying the potential of bird strikes and is continuing to study bird behaviour leading to collisions, the impact of topography, cumulative impacts and new techniques to reduce bird strikes. Despite the reported incidents, the risk of bird strikes by wind turbines, compared to other threats to birds such as pollution, oil spills, and other threats from fossil and nuclear fuels, is considered to be negligible. With continuing efforts to minimize incidents by proper design and siting, wind power can continue to grow as an environmentally sound and efficient source of energy

  1. Wind power and bird kills

    Energy Technology Data Exchange (ETDEWEB)

    Raynolds, M.

    1998-12-01

    The accidental killing of birds by wind generators, and design improvements in the towers that support the turbines that might cut down on the bird killings were discussed. The first problem for the industry began in the late 1980s when the California Energy Commission reported as many as 160 birds (the majority being raptors, including the protected golden eagle) killed in one year in the vicinity of wind power plants. The key factor identified was the design of the towers as birds of prey are attracted to lattice towers as a place to hunt from. Tubular towers do not provide a place for the birds to perch, therefore they reduce the potential for bird strikes. Bird strikes also have been reported in Spain and the siting of the towers have been considered as the principal cause of the bird strikes. In view of these incidents, the wind power industry is developing standards for studying the potential of bird strikes and is continuing to study bird behaviour leading to collisions, the impact of topography, cumulative impacts and new techniques to reduce bird strikes. Despite the reported incidents, the risk of bird strikes by wind turbines, compared to other threats to birds such as pollution, oil spills, and other threats from fossil and nuclear fuels, is considered to be negligible. With continuing efforts to minimize incidents by proper design and siting, wind power can continue to grow as an environmentally sound and efficient source of energy.

  2. Developmental post-natal stress can alter the effects of pre-natal stress on the adult redox balance.

    Science.gov (United States)

    Marasco, Valeria; Spencer, Karen A; Robinson, Jane; Herzyk, Pawel; Costantini, David

    2013-09-15

    Across diverse vertebrate taxa, stressful environmental conditions during development can shape phenotypic trajectories of developing individuals, which, while adaptive in the short-term, may impair health and survival in adulthood. Regardless, the long-lasting benefits or costs of early life stress are likely to depend on the conditions experienced across differing stages of development. Here, we used the Japanese quail (Coturnix coturnix japonica) to experimentally manipulate exposure to stress hormones in developing individuals. We tested the hypothesis that interactions occurring between pre- and post-natal developmental periods can induce long-term shifts on the adult oxidant phenotype in non-breeding sexually mature individuals. We showed that early life stress can induce long-term alterations in the basal antioxidant defences. The magnitude of these effects depended upon the timing of glucocorticoid exposure and upon interactions between the pre- and post-natal stressful stimuli. We also found differences among tissues with stronger effects in the erythrocytes than in the brain in which the long-term effects of glucocorticoids on antioxidant biomarkers appeared to be region-specific. Recent experimental work has demonstrated that early life exposure to stress hormones can markedly reduce adult survival (Monaghan et al., 2012). Our results suggest that long-term shifts in basal antioxidant defences might be one of the potential mechanisms driving such accelerated ageing processes and that post-natal interventions during development may be a potential tool to shape the effects induced by pre-natally glucococorticoid-exposed phenotypes. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Don't bet against the natal homing abilities of marine fishes.

    Science.gov (United States)

    Bentzen, Paul; Bradbury, Ian R

    2016-06-01

    Whether marine fishes are capable of homing to their natal areas has long been something of an enigma. For some estuarine species or sharks (which have extended nondispersal juvenile stages or are born as relatively large, fully formed juveniles), the answer is clearly 'yes' (Thorrold et al. ; Feldheim et al. ), but for most marine fishes, the issue is much more mysterious. Many species have free-floating eggs, and most have pelagic, passively dispersing larvae. It is challenging to imagine how adult fish might navigate to a region of the ocean they experienced only as eggs or larvae, and easier to assume that such dispersal leads inexorably to high gene flow, and even panmixia. One way to resolve the conundrum would be to track fish from hatching to reproduction, but for marine fishes with tiny eggs and drifting larvae, this is notoriously difficult to do (Bradbury & Laurel ). In this issue of Molecular Ecology, Bonanomi et al. () use a creative approach to solve this challenge for Atlantic cod (Gadus morhua) populations that mingle in the vicinity of Greenland. They show that cod that disperse more than a 1000 km away from Iceland as eggs and larvae, then spend years growing on the far side of Greenland, while mixing with two local populations, return as adults to spawning areas near Iceland - and further, that this behaviour has remained stable over more than six decades. They manage this feat with a clever use of historical cod tracking data, modern genomic data and genetic analysis of decades-old DNA obtained from archived materials. Their results have important implications for our view of the biocomplexity of marine fish populations, and how we should manage them. © 2016 John Wiley & Sons Ltd.

  4. Dispersal patterns of red foxes relative to population density

    Science.gov (United States)

    Allen, Stephen H.; Sargeant, Alan B.

    1993-01-01

    Factors affecting red fox (Vulpes vulpes) dispersal patterns are poorly understood but warranted investigation because of the role of dispersal in rebuilding depleted populations and transmission of diseases. We examined dispersal patterns of red foxes in North Dakota based on recoveries of 363 of 854 foxes tagged as pups and relative to fox density. Foxes were recovered up to 8.6 years after tagging; 79% were trapped or shot. Straight-line distances between tagging and recovery locations ranged from 0 to 302 km. Mean recovery distances increased with age and were greater for males than females, but longest individual recovery distances were by females. Dispersal distances were not related to population density for males (P = 0.36) or females (P = 0.96). The proportion of males recovered that dispersed was inversely related to population density (r = -0.94; n = 5; P = 0.02), but not the proportion of females (r = -0.49; n = 5; P = 0.40). Dispersal directions were not uniform for either males (P = 0.003) or females (P = 0.006); littermates tended to disperse in similar directions (P = 0.09). A 4-lane interstate highway altered dispersal directions (P = 0.001). Dispersal is a strong innate behavior of red foxes (especially males) that results in many individuals of both sexes traveling far from natal areas. Because dispersal distance was unaffected by fox density, populations can be rebuilt and diseases transmitted long distances regardless of fox abundance.

  5. Europe's last Mesozoic bird

    NARCIS (Netherlands)

    Dyke, Gareth J.; Dortangs, Rudi W.; Jagt, John W.; Mulder, Eric W. A.; Schulp, Anne S.; Chiappe, Luis M.

    2002-01-01

    Birds known from more than isolated skeletal elements are rare in the fossil record, especially from the European Mesozoic. This paucity has hindered interpretations of avian evolution immediately prior to, and in the aftermath of, the Cretaceous-Tertiary (K-T) extinction event. We report on a

  6. The Umbrella Bird

    NARCIS (Netherlands)

    Crandall, Lee S.

    1949-01-01

    When CHARLES CORDIER arrived from Costa Rica on October 9, 1942, bringing with him, among other great rarities, three Bare-necked Umbrella Birds (Cephalopterus ornatus glabricollis), it seemed to us that the mere possession of such fabulous creatures was satisfaction enough. True, they were not

  7. Timber and forest birds

    Science.gov (United States)

    Brian Roy Lockhart

    2009-01-01

    Many years ago, I had an epiphany that I would like to share. Several students and I were installing research plots in the forests on Pittman Island, Issaquena County, Mississippi, an island adjacent to the Mississippi River, near the borders of Arkansas, Mississippi, and Louisiana. While eating lunch, we watched a bird, more specifically a prothonotary warbler (

  8. Fish, birds and flies

    Science.gov (United States)

    Gibbings, J. C.

    2013-04-01

    The article in your animal physics special issue on the use of magnetic field sensing in bird navigation (November 2012 pp38-42) reminded me of a comment made regarding a paper that I presented in the US many years ago.

  9. Cavity Nesting Birds

    Science.gov (United States)

    Virgil E. Scott; Keith E. Evans; David R. Patton; Charles P. Stone

    1977-01-01

    Many species of cavity-nesting birds have declined because of habitat reduction. In the eastern United States, where primeval forests are gone, purple martins depend almost entirely on man-made nesting structures (Allen and Nice 1952). The hole-nesting population of peregrine falcons disappeared with the felling of the giant trees upon which they depended (Hickey and...

  10. Eating Like a Bird.

    Science.gov (United States)

    Brothers, Chris; Fortner, Rosanne W.

    This teacher guide and student workbook set contains two learning activities, designed for fifth through ninth grade students, that concentrate on the adaptations of shorebird beaks for a variety of habitats and food sources, and the effect of toxic chemicals in the food chain on the birds. In activity A, students discover how shorebirds are…

  11. Breeding Ecology of Birds -22 ...

    Indian Academy of Sciences (India)

    or drive the birds away. However, the droppings of the birds provide a rich source of fertilizer and this ... birds of India are under severe threat and require urgent protection. he~ries'(Box 1), can ... there will be no fish and then suddenly a school.

  12. 14 CFR 33.76 - Bird ingestion.

    Science.gov (United States)

    2010-01-01

    ... single bird, the single largest medium bird which can enter the inlet, and the large flocking bird must...) (d) Large flocking bird. An engine test will be performed as follows: (1) Large flocking bird engine.... (4) Ingestion of a large flocking bird under the conditions prescribed in this paragraph must not...

  13. Global Dynamics of Dispersal and Diversification among Passerine Birds

    DEFF Research Database (Denmark)

    Kennedy, Jonathan David

    Global variation in the distribution and diversity of species has been recognized by naturalists for centuries. However, despite extensive scientific study since the initial documentation of these patterns, we still lack a comprehensive explanation as to their underlying causes. Ultimately, this ...

  14. Dispersal and biogeography of silica-scaled chrysophytes

    DEFF Research Database (Denmark)

    Kristiansen, Jørgen

    2008-01-01

    The silica-scaled chrysophytes—here mainly represented by the freshwater genera Mallomonas and Synura—have special problems in dispersal from one habitat to another because they cannot tolerate desiccation. Their dispersal is limited by the fragile construction and aquatic habit. Dispersal from one...... water body to another involves dangerous changes of the environment, and the ability to avoid desiccation during transport is crucial. So, air-borne and ectozoic dispersal by birds or mammals can only work at short distances. This danger may be avoided by endozoic dispersal of thick-walled cysts; as far....... The distribution of a species at a given time depends on several factors: dispersal capacity—available vectors—suitable available habitats—and most important: sufficient time for dispersal. It is remarkable that the chrysophytes—in spite of their fragile cell construction and apparently low dispersal capacity...

  15. Impact of mimicking natural dispersion on breeding success of captive North American Cheetahs (Acinonyx jubatus).

    Science.gov (United States)

    Gillman, Sierra J; Ziegler-Meeks, Karen; Eager, Carol; Tenhundfeld, Thomas A; Shaffstall, Wendy; Stearns, Mary Jo; Crosier, Adrienne E

    2017-09-01

    This paper examines the effects of transfer away from natal facility and littermate presence on cheetah breeding success in the AZA Species Survival Plan (SSP) population. Transfer and breeding history data for captive males and females were gathered from seven and four AZA SSP breeding facilities, respectively, to identify factors influencing breeding success. The results indicate that transfer history (p = 0.032), age at transfer (p = 0.013), and female littermate presence/absence (p = 0.04) was associated with breeding success, with females transferred away from their natal facility before sexual maturity and without littermates present accounting for the highest breeding success. Keeping males at their natal facility and/or removing them from their coalitions did not negatively affect their breeding success. Males appeared to demonstrate the same fecundity regardless of transfer history or coalition status, indicating that dispersal away from natal environment was not as critical for the breeding success of males compared with female cheetahs. These results highlight the significance of moving females away from their natal environment, as would occur in the wild, and separating them from their female littermates for optimization of breeding success in the ex situ population. © 2017 Wiley Periodicals, Inc.

  16. Studying wind energy/bird interactions: a guidance document. Metrics and methods for determining or monitoring potential impacts on birds at existing and proposed wind energy sites

    Science.gov (United States)

    Anderson, R.; Morrison, M.; Sinclair, K.; Strickland, D.; Davis, H.; Kendall, W.

    1999-01-01

    In the 1980s little was known about the potential environmental effects associated with large scale wind energy development. Although wind turbines have been used in farming and remote location applications throughout this country for centuries, impacts on birds resulting from these dispersed turbines had not been reported. Thus early wind energy developments were planned, permitted, constructed, and operated with little consideration for the potential effects on birds. In the ensuing years wind plant impacts on birds became a source of concern among a number of stakeholder groups. Based on the studies that have been done to date, significant levels of bird fatalities have been identified at only one major commercial wind energy development in the United States. Research on wind energy/bird interactions has spanned such a wide variety of protocols and vastly different levels of study effort that it is difficult to make comparisons among study findings. As a result there continues to be interest, confusion, and concern over wind energy development's potential impacts on birds. Some hypothesize that technology changes, such as less dense wind farms with larger, slower-moving turbines, will decrease the number of bird fatalities from wind turbines. Others hypothesize that, because the tip speed may be the same or faster, new turbines will not result in decreased bird fatalities but may actually increase bird impacts. Statistically significant data sets from scientifically rigorous studies will be required before either hypothesis can be tested.

  17. Alien invasive birds.

    Science.gov (United States)

    Brochier, B; Vangeluwe, D; van den Berg, T

    2010-08-01

    A bird species is regarded as alien invasive if it has been introduced, intentionally or accidentally, to a location where it did not previously occur naturally, becomes capable of establishing a breeding population without further intervention by humans, spreads and becomes a pest affecting the environment, the local biodiversity, the economy and/or society, including human health. European Starling (Sturnus vulgaris), Common Myna (Acridotheres tristis) and Red-vented Bulbul (Pycnonotus cafer) have been included on the list of '100 of the World's Worst Invasive Alien Species', a subset of the Global Invasive Species Database. The 'Delivering Alien Invasive Species Inventories for Europe' project has selected Canada Goose (Branta canadensis), Ruddy Duck (Oxyura jamaicensis), Rose-ringed Parakeet (Psittacula krameri) and Sacred Ibis (Threskiornis aethiopicus) as among 100 of the worst invasive species in Europe. For each of these alien bird species, the geographic range (native and introduced range), the introduction pathway, the general impacts and the management methods are presented.

  18. Windmills and birds

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, N W; Poulsen, E

    1984-07-01

    The objective of this study is an investigation of potential conflicts between windmills and birds. Emphasis is on frightening, collision risk and biotopic changes due to windmill systems. The study is based on the environment of Koldby and Nibe windmills (South Jutland). Biotopic changes were not observed around the existing windmills. Drainage of mill grounds at Nibe had probably no effect on water level in the area around; a longer observation is necessary to draw any decisive conclusions.(EG).

  19. Olfactory responses to natal stream water in sockeye salmon by BOLD fMRI.

    Directory of Open Access Journals (Sweden)

    Hiroshi Bandoh

    Full Text Available Many studies have shown that juvenile salmon imprint olfactory memory of natal stream odors during downstream migration, and adults recall this stream-specific odor information to discriminate their natal stream during upstream migration for spawning. The odor information processing of the natal stream in the salmon brain, however, has not been clarified. We applied blood oxygenation level-dependent (BOLD functional magnetic resonance imaging to investigate the odor information processing of the natal stream in the olfactory bulb and telencephalon of lacustrine sockeye salmon (Oncorhynchus nerka. The strong responses to the natal stream water were mainly observed in the lateral area of dorsal telencephalon (Dl, which are homologous to the medial pallium (hippocampus in terrestrial vertebrates. Although the concentration of L-serine (1 mM in the control water was 20,000-times higher than that of total amino acid in the natal stream water (47.5 nM, the BOLD signals resulting from the natal stream water were stronger than those by L-serine in the Dl. We concluded that sockeye salmon could process the odor information of the natal stream by integrating information in the Dl area of the telencephalon.

  20. Observations of the vertical and temporal evolution of a Natal Pulse along the Eastern Agulhas Bank

    CSIR Research Space (South Africa)

    Pivan, X

    2016-09-01

    Full Text Available describe the evolution of a Natal Pulse along three density surfaces referred to as the surface (satellite-observed), shallow (isopycnal 1026.8 kg m-3), and deep (isopycnal 1027.2 kg m-3) layer. Our observations show that this Natal Pulse extended to a...

  1. Water temperature affects life-cycle duration of tadpoles of Natal ...

    African Journals Online (AJOL)

    Direct and indirect effects of climate change on amphibians include range shifts and changes in community structure. The Natal cascade frog Hadromophryne natalensis has an altitudinal range of some 2 400 m in KwaZulu-Natal, and presents an opportunity to assess how increased water temperatures may impact on ...

  2. Sharks caught in the protective gill nets off KwaZulu-Natal, South ...

    African Journals Online (AJOL)

    Between 1978 and 1998, a total of 3 385 scalloped hammerhead sharks Sphyrna lewini was caught in the protective nets off KwaZulu-Natal. The mean annual catch was 166 sharks (range 60–279). There was a significant decrease in catch rate with time, but the relationship with the population size in KwaZulu-Natal waters ...

  3. Developing telepsychiatry services in KwaZulu-Natal – an action ...

    African Journals Online (AJOL)

    Objective: In 2009, the Departments of Psychiatry and Telehealth of the University of KwaZulu-Natal (UKZN) initiated a three year project to develop telepsychiatry services in KwaZulu-Natal. This paper describes the challenges and opportunities of this project. Method: This was a collaborative, in situ health service project ...

  4. Equity and Excellence: The Emergence, Consolidation and Internalization of Education Development at the University of Natal

    Science.gov (United States)

    Odendaal, Marie; Deacon, Roger

    2009-01-01

    Education development in South Africa emerged during the transition from apartheid to democracy, in a context especially marked by political and financial pressures. This case study of the University of Natal (now the University of KwaZulu-Natal) demonstrates how a strategy combining equity with excellence aimed to facilitate increased access to…

  5. Modern beachrock formation in Durban, KwaZulu-Natal

    Directory of Open Access Journals (Sweden)

    Hayley Cawthra

    2012-07-01

    Full Text Available We explored the recent cementation of modern beachrock on the seaward margin of the Durban Bluff, central KwaZulu-Natal. The low latitude and subtropical climatic setting is a unique context compared to the more commonly documented contemporary beachrock formation in the tropics. Geological field mapping was carried out and here we present results based on sedimentary facies of a clastic shoreline and carbonate diagenesis of interstitial cements using transmitted light microscopy. The beachrock was cemented by micrite and aragonite, and iron oxide infilled voids. The presence of human artefacts within the deposit showed evidence for cementation within the last century. The elevation (at Mean Low Water and correlation to rates of sea level change for the east coast of South Africa showed that the beachrock is less than 72 years in age. In contrast to older local Pleistocene deposits, beachrocks have cemented along this stretch of coast during successive sea level highstands with similar climatic regimes – the last Interglacial, the Holocene High and the present. Here we report the most southerly documentation of modern beachrock in KwaZulu-Natal, which, to our knowledge, represents the youngest deposit reported in southern Africa.

  6. Dispersion strengthening

    International Nuclear Information System (INIS)

    Scattergood, R.O.; Das, E.S.P.

    1976-01-01

    Using digital computer-based methods, models for dispersion strengthening can now be developed which take into account many of the important effects that have been neglected in the past. In particular, the self interaction of a dislocation can be treated, and a computer simulation method was developed to determine the flow stress of a random distribution of circular, impenetrable obstacles, taking into account all such interactions. The flow stress values depended on the obstacle sizes and spacings, over and above the usual 1/L dependence where L is the average obstacle spacing. From an analysis of the results, it was found that the main effects of the self interactions can be captured in a line tension analogue in which the obstacles appear to be penetrable

  7. The North Sea Bird Club

    International Nuclear Information System (INIS)

    Doyle, P.A.T.; Gorman, M.L.; Patterson, I.J.; Howe, S.

    1991-01-01

    This paper reports that the creation of a club for the purpose of encouraging oil and gas workers to watch birds may not at first seem a viable proposition. To the layperson, birds offshore conjures up an image of hundreds of seagulls following fishing boats, and very little else. Also, the act of birdwatching is not seen as a typical offshore worker's activity. Anyone who has worked on an installation offshore and who has any interest in wildlife will be aware of the occasional presence of land-birds. Two decades ago, prompted by some keen offshore workers, a single oil company set up a monitoring program, which quickly became popular with a number of its employees. Birds seem offshore were recorded on data forms and collected together. At this stage the club was purely another recreation facility; however, when the data were collated it was soon realized that installations offshore were being used as staging posts by birds on migration, and that the information being collected would be of great interest in the study of bird movements. All over Britain, at strategic points on the coastline, there are bird observatories which record the arrival and departure of migrating birds. The presence of several hundred solid structures up and down the North Sea, which are used by birds en route, represents a huge, unique bird observatory, capable of uncovering facts about bird migration which have long eluded land-based scientists. Eleven years ago, the North Sea Bird Club began, composed of eight member companies, a recorder from Aberdeen University and a representative from the Nature Conservancy Council. The club received data from 41 installations, and the recorder collated these on Aberdeen University's computer and produced an annual report of sightings

  8. Rhode Island, Connecticut, New York, and New Jersey ESI: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, raptors, diving birds, pelagic birds, passerine birds, gulls and...

  9. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Upper Coast of Texas: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for diving birds, gulls, terns, passerine birds, pelagic birds, raptors, shorebirds, wading birds,...

  10. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: South Florida: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for diving birds, gulls, terns, passerine birds, pelagic birds, raptors, shorebirds, wading birds, and...

  11. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Central California: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for alcids, diving birds, gulls, terns, passerine birds, pelagic birds, raptors, shorebirds, wading birds,...

  12. Hydrodynamic dispersion

    International Nuclear Information System (INIS)

    Pryce, M.H.L.

    1985-01-01

    A dominant mechanism contributing to hydrodynamic dispersion in fluid flow through rocks is variation of travel speeds within the channels carrying the fluid, whether these be interstices between grains, in granular rocks, or cracks in fractured crystalline rocks. The complex interconnections of the channels ensure a mixing of those parts of the fluid which travel more slowly and those which travel faster. On a macroscopic scale this can be treated statistically in terms of the distribution of times taken by a particle of fluid to move from one surface of constant hydraulic potential to another, lower, potential. The distributions in the individual channels are such that very long travel times make a very important contribution. Indeed, while the mean travel time is related to distance by a well-defined transport speed, the mean square is effectively infinite. This results in an asymmetrical plume which differs markedly from a gaussian shape. The distribution of microscopic travel times is related to the distribution of apertures in the interstices, or in the microcracks, which in turn are affected in a complex way by the stresses acting on the rock matrix

  13. As origens das comemorações do Natal

    Directory of Open Access Journals (Sweden)

    Auguste Hollard

    1966-06-01

    Full Text Available A festa de Natal (1 nem sempre foi celebrada a 25 de dezembro. Na falta de qualquer documento que registrasse o dia de nascimento de Jesus, os cristãos procuraram, a princípio, as hipóteses mais fantásticas e contraditórias. Mais tarde, já no século III, as Igrejas do Oriente passaram a comemorar a Natividade no dia da Epifania (5-6 de janeiro . Somente a partir do século IV, é que a Igreja de Roma encontrou outra data, o dia 25 de dezembro, que era a data em que se celebrava a festa do Sol, e que lentamente veio a impor-se para tôda a Cristandade.

  14. Canto pré-natal: alquimias sonoras para gestantes

    Directory of Open Access Journals (Sweden)

    Janaina Trasel Martins

    2017-10-01

    Full Text Available Este artigo irá focar no canto pré-natal; nos benefícios da música e do canto durante a gestação; na audição do feto no ventre e na escuta da gestante do seu corpo. Como metodologia para pesquisar sobre estes temas foram realizados estudos teóricos nas áreas da musicoterapia obstétrica, da terapia sonora e da medicina e também foram realizadas práticas de canto pré-natal. Arte, movimento e saúde são integrados com as alquimias sonoras para ampliar a consciência da corporeidade da mulher durante a gestação. Com cantos femininos em um círculo de mulheres, nos apoiamos e nos fortalecemos durante a gestação e enviamos vibrações sonoras harmoniosas para o bebê no ventre. ABSTRACT This article will focus on prenatal singing; on the benefits of music and singing during pregnancy; on the baby's hearing in the womb and on the listening of the pregnant woman to her body. To determine the methodology for researching these themes, theoretical studies were done in obstetrical music therapy, sound therapy, medicine and also practical research in prenatal singing classes. Art, movement and health are integrated with sound alchemy to widen the woman’s body awareness during pregnancy. With feminine chants in a circle of women, we support and strengthen ourselves during pregnancy and we send harmonious sounds vibrations to the baby in the womb. KEYWORDS Prenatal singing, prenatal music, pregnancy, listening, consciousness.

  15. Ophthalmic effects of petroleum dispersant exposure on common murres (Uria aalge): An experimental study.

    Science.gov (United States)

    Fiorello, Christine V; Freeman, Kate; Elias, Becky A; Whitmer, Emily; Ziccardi, Michael H

    2016-12-15

    The safety of chemical dispersants used during oil spill responses is largely unknown in birds. We captured common murres in Monterey Bay, CA and exposed them to Corexit EC9500a, crude oil, or a combination in artificial seawater. We performed ophthalmic examinations and measured intraocular pressures and tear production before and after exposure. Loglinear analysis found that exposure to oil or dispersant was related to the development of conjunctivitis and corneal ulcers. Odds ratios for birds exposed to oil or dispersant were positive and significant for the development of conjunctivitis, while odds ratios for the development of corneal ulcers were positive and significant only for birds exposed to a high concentration of oil. Ocular exposure to dispersants and petroleum in seabirds may cause conjunctivitis and may play a role in the development of corneal ulcers. These results have implications for policymakers who develop protocols for the use of dispersants during marine oil spills. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Laboratory Animal Management: Wild Birds.

    Science.gov (United States)

    National Academy of Sciences - National Research Council, Washington, DC. Inst. of Lab. Animal Resources.

    This is a report on the care and use of wild birds in captivity as research animals. Chapters are presented on procurement and identification, housing, nutrition, health of birds and personnel, reproduction in confinement, and surgical procedures. Also included are addresses of federal, state, and provencial regulatory agencies concerned with wild…

  17. The effect of feeding time on dispersal of Virola seeds by toucans determined from GPS tracking and accelerometers

    NARCIS (Netherlands)

    Kays, Roland; Jansen, Patrick A.; Knecht, Elise M. H.; Vohwinkel, Reinhard; Wikelski, Martin

    2011-01-01

    Seed dispersal is critical to understanding forest dynamics but is hard to study because tracking seeds is difficult. Even for the best-studied dispersal system of the Neotropics, Virola nobilis, the dispersal kernel remains unknown. We combined high-resolution GPS/3D-acceleration bird tracking,

  18. Resumes of the Bird mission

    Science.gov (United States)

    Lorenz, E.; Borwald, W.; Briess, K.; Kayal, H.; Schneller, M.; Wuensten, Herbert

    2004-11-01

    The DLR micro satellite BIRD (Bi-spectral Infra Red Detection) was piggy- back launched with the Indian Polar Satellite Launch Vehicle PSLV-C3 into a 570 km circular sun-synchronous orbit on 22 October 2001. The BIRD mission, fully funded by the DLR, answers topical technological and scientific questions related to the operation of a compact infra- red push-broom sensor system on board of a micro satellite and demonstrates new spacecraft bus technologies. BIRD mission control is conducted by DLR / GSOC in Oberpfaffenhofen. Commanding, data reception and data processing is performed via ground stations in Weilheim and Neustrelitz (Germany). The BIRD mission is a demonstrator for small satellite projects dedicated to the hazard detection and monitoring. In the year 2003 BIRD has been used in the ESA project FUEGOSAT to demonstrate the utilisation of innovative space technologies for fire risk management.

  19. Unzipping bird feathers.

    Science.gov (United States)

    Kovalev, Alexander; Filippov, Alexander E; Gorb, Stanislav N

    2014-03-06

    The bird feather vane can be separated into two parts by pulling the barbs apart. The original state can be re-established easily by lightly stroking through the feather. Hooklets responsible for holding vane barbs together are not damaged by multiple zipping and unzipping cycles. Because numerous microhooks keep the integrity of the feather, their properties are of great interest for understanding mechanics of the entire feather structure. This study was undertaken to estimate the separation force of single hooklets and their arrays using force measurement of an unzipping feather vane. The hooklets usually separate in some number synchronously (20 on average) with the highest observed separation force of 1.74 mN (average force 0.27 mN), whereas the single hooklet separation force was 14 μN. A simple numerical model was suggested for a better understanding of zipping and unzipping behaviour in feathers. The model demonstrates features similar to those observed in experiments.

  20. Tracking migrating birds

    DEFF Research Database (Denmark)

    Willemoes, Mikkel

    habitats with those in rural habitats. Some species have decreased the frequency of migrants and migration distance in urban environments, and others have not. The other manuscript describes the small scale movements of three different Palaearctic migrants during winter in Africa in a farmland habitat....... In another species, environmental conditions are not a good predictor of movements, and possibly effects of timing constraints or food type play a role. Two manuscripts focus on the effects of human-induced habitat alterations on migratory behaviour. One compares the movements of partial migrants in urban...... and a forest reserve. In the degraded habitat all species used more space, although the consequence on bird density is less clear. Two manuscripts relate the migratory movements of a long-distance migrant with models of navigation. One compares model predictions obtained by simulation with actual movements...

  1. Lessons learned from research and surveillance directed at highly pathogenic influenza A viruses in wild birds inhabiting North America

    Science.gov (United States)

    Ramey, Andy M.; DeLiberto, Thomas J.; Berhane, Yohannes; Swayne, David E.; Stallknecht, David E.

    2018-01-01

    Following detections of highly pathogenic (HP) influenza A viruses (IAVs) in wild birds inhabiting East Asia after the turn of the millennium, the intensity of sampling of wild birds for IAVs increased throughout much of North America. The objectives for many research and surveillance efforts were directed towards detecting Eurasian origin HP IAVs and understanding the potential of such viruses to be maintained and dispersed by wild birds. In this review, we highlight five important lessons learned from research and surveillance directed at HP IAVs in wild birds inhabiting North America: (1) Wild birds may disperse IAVs between North America and adjacent regions via migration, (2) HP IAVs can be introduced to wild birds in North America, (3) HP IAVs may cross the wild bird-poultry interface in North America, (4) The probability of encountering and detecting a specific virus may be low, and (5) Population immunity of wild birds may influence HP IAV outbreaks in North America. We review empirical support derived from research and surveillance efforts for each lesson learned and, furthermore, identify implications for future surveillance efforts, biosecurity, and population health. We conclude our review by identifying five additional areas in which we think future mechanistic research relative to IAVs in wild birds in North America are likely to lead to other important lessons learned in the years ahead.

  2. Lessons learned from research and surveillance directed at highly pathogenic influenza A viruses in wild birds inhabiting North America.

    Science.gov (United States)

    Ramey, Andrew M; DeLiberto, Thomas J; Berhane, Yohannes; Swayne, David E; Stallknecht, David E

    2018-05-01

    Following detections of highly pathogenic (HP) influenza A viruses (IAVs) in wild birds inhabiting East Asia after the turn of the millennium, the intensity of sampling of wild birds for IAVs increased throughout much of North America. The objectives for many research and surveillance efforts were directed towards detecting Eurasian origin HP IAVs and understanding the potential of such viruses to be maintained and dispersed by wild birds. In this review, we highlight five important lessons learned from research and surveillance directed at HP IAVs in wild birds inhabiting North America: (1) Wild birds may disperse IAVs between North America and adjacent regions via migration, (2) HP IAVs can be introduced to wild birds in North America, (3) HP IAVs may cross the wild bird-poultry interface in North America, (4) The probability of encountering and detecting a specific virus may be low, and (5) Population immunity of wild birds may influence HP IAV outbreaks in North America. We review empirical support derived from research and surveillance efforts for each lesson learned and, furthermore, identify implications for future surveillance efforts, biosecurity, and population health. We conclude our review by identifying five additional areas in which we think future mechanistic research relative to IAVs in wild birds in North America are likely to lead to other important lessons learned in the years ahead. Published by Elsevier Inc.

  3. Seed dispersal in fens

    NARCIS (Netherlands)

    Middleton, Beth; van Diggelen, Rudy; Jensen, Kai

    Question: How does seed dispersal reduce fen isolation and contribute to biodiversity? Location: European and North American fens. Methods: This paper reviews the literature on seed dispersal to fens. Results: Landscape fragmentation may reduce dispersal opportunities thereby isolating fens and

  4. The beach-seine fishery off Durban, KwaZulu-Natal

    African Journals Online (AJOL)

    1996-07-23

    Jul 23, 1996 ... the mean weight of a crate of fish, mean lengths of fish caught .... or beyond the Natal Sharks Board protective shark nets. (approximately 300 m offshore). ..... Spotfin flathead. White karanteen ... Great barracuda. Yellow stripe ...

  5. Modelling long-distance seed dispersal in heterogeneous landscapes.

    Energy Technology Data Exchange (ETDEWEB)

    Levey, Douglas, J.; Tewlsbury, Joshua, J.; Bolker, Benjamin, M.

    2008-01-01

    1. Long-distance seed dispersal is difficult to measure, yet key to understanding plant population dynamics and community composition. 2. We used a spatially explicit model to predict the distribution of seeds dispersed long distances by birds into habitat patches of different shapes. All patches were the same type of habitat and size, but varied in shape. They occurred in eight experimental landscapes, each with five patches of four different shapes, 150 m apart in a matrix of mature forest. The model was parameterized with smallscale movement data collected from field observations of birds. In a previous study we validated the model by testing its predictions against observed patterns of seed dispersal in real landscapes with the same types and spatial configuration of patches as in the model. 3. Here we apply the model more broadly, examining how patch shape influences the probability of seed deposition by birds into patches, how dispersal kernels (distributions of dispersal distances) vary with patch shape and starting location, and how movement of seeds between patches is affected by patch shape. 4. The model predicts that patches with corridors or other narrow extensions receive higher numbers of seeds than patches without corridors or extensions. This pattern is explained by edgefollowing behaviour of birds. Dispersal distances are generally shorter in heterogeneous landscapes (containing patchy habitat) than in homogeneous landscapes, suggesting that patches divert the movement of seed dispersers, ‘holding’ them long enough to increase the probability of seed defecation in the patches. Dispersal kernels for seeds in homogeneous landscapes were smooth, whereas those in heterogenous landscapes were irregular. In both cases, long-distance (> 150 m) dispersal was surprisingly common, usually comprising approximately 50% of all dispersal events. 5. Synthesis . Landscape heterogeneity has a large influence on patterns of long-distance seed dispersal. Our

  6. Population Change in a Marine Bird Colony is Driven By Changes in Recruitment

    Directory of Open Access Journals (Sweden)

    Anthony J. Gaston

    2011-12-01

    Full Text Available The population dynamics of long-lived birds are thought to be very sensitive to changes in adult survival. However, where natal philopatry is low, recruitment from the larger metapopulation may have the strongest effect on population growth rate even in long-lived species. Here, we illustrate such a situation where changes in a seabird colony size appeared to be the consequence of changes in recruitment. We studied the population dynamics of a declining colony of Ancient Murrelets (Synthliboramphus antiquus at East Limestone Island, British Columbia. During 1990-2010, Ancient Murrelet chicks were trapped at East Limestone Island while departing to sea, using a standard trapping method carried on throughout the departure period. Adult murrelets were trapped while departing from the colony during 1990-2003. Numbers of chicks trapped declined during 1990-1995, probably because of raccoon predation, increased slightly from 1995-2000 and subsequently declined again. Reproductive success was 30% lower during 2000-2003 than in earlier years, mainly because of an increase in desertions. The proportion of nonbreeders among adult birds trapped at night also declined over the study period. Mortality of adult birds, thought to be mainly prebreeders, from predators more than doubled over the same period. Apparent adult survival of breeders remained constant during 1991-2002 once the first year after banding was excluded, but the apparent survival rates in the first year after banding fell and the survival of birds banded as chicks to age three halved over the same period. A matrix model of population dynamics suggested that even during the early part of the study immigration from other breeding areas must have been substantial, supporting earlier observations that natal philopatry in this species is low. The general colony decline after 2000 probably was related to diminished recruitment, as evidenced by the lower proportion of nonbreeders in the trapped

  7. Bird on a (live) wire

    Energy Technology Data Exchange (ETDEWEB)

    Farr, M.

    2003-09-30

    Bird mortality as a result of contact with power lines is discussed. U. S. statistics are cited, according to which 174 million birds annually die as a result of contact with power lines, specifically when birds touch two phases of current at the same time. Raptors are particularly vulnerable to power-line electrocution due to their habit of perching on the highest vantage point available as they survey the ground for prey. Hydro lines located in agricultural areas, with bodies of water on one side and fields on the other, also obstruct flight of waterfowl as dusk and dawn when visibility is low. Various solutions designed to minimize the danger to birds are discussed. Among these are: changing the configuration of wires and cross arms to make them more visible to birds in flight and less tempting as perches, and adding simple wire markers such as flags, balloons, and coloured luminescent clips that flap and twirl in the wind. There is no evidence of any coordinated effort to deal with this problem in Ontario. However, a report is being prepared for submission to Environment Canada outlining risks to birds associated with the growing number of wind turbine power generators (negligible compared with power lines and communications towers), and offering suggestions on remedial measures. The Fatal Light Awareness Program (FLAP) also plans to lobby the Canadian Wildlife Service to discuss the possibility of coordinating efforts to monitor, educate about and ultimately reduce this form of bird mortality.

  8. Dente natal em recém-nascido pré-termo: relato de caso

    OpenAIRE

    ROCHA, Jenifer Garcia; SARMENTO, Lilian Citty; GOMES, Ana Maria Martins; VALLE, Marly Almeida Saleme do; DADALTO, Elâine Cristina Vargas

    2017-01-01

    ABSTRACT Low birth weight and prematurity may be associated with delayed dental eruption in the deciduous dentition; notwithstanding this relationship, cases of preterm newborns presenting natal or neonatal teeth have been reported in the literature, although this is a rare occurrence. The objective was to present the report of natal tooth in a preterm newborn, analyzing the uniqueness of this case in contrast to the delayed dental eruption usually observed in association with prematurity. Ca...

  9. Bristol Bay, Alaska Subarea ESI: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for shorebirds, waterfowl, raptors, diving birds, and seabirds in the Bristol Bay Subarea. The Subarea...

  10. Birds of the Mongol Empire

    Directory of Open Access Journals (Sweden)

    Eugene N. Anderson

    2016-09-01

    Full Text Available The Mongol Empire, the largest contiguous empire the world has ever known, had, among other things, a goodly number of falconers, poultry raisers, birdcatchers, cooks, and other experts on various aspects of birding. We have records of this, largely in the Yinshan Zhengyao, the court nutrition manual of the Mongol empire in China (the Yuan Dynasty. It discusses in some detail 22 bird taxa, from swans to chickens. The Huihui Yaofang, a medical encyclopedia, lists ten taxa used medicinally. Marco Polo also made notes on Mongol bird use. There are a few other records. This allows us to draw conclusions about Mongol ornithology, which apparently was sophisticated and detailed.

  11. Small seed size increases the potential for dispersal of wetland plants by ducks

    NARCIS (Netherlands)

    Soons, M.B.; van der Vlugt, C.; van Lith, B.; Heil, G.W.; Klaassen, M.R.J.

    2008-01-01

    1. Long-distance dispersal (LDD) is important in plants of dynamic and ephemeral habitats. For plants of dynamic wetland habitats, waterfowl are generally considered to be important LDD vectors. However, in comparison to the internal (endozoochorous) dispersal of terrestrial plants by birds,

  12. Digestive plasticity in Mallard ducks modulates dispersal probabilities of aquatic plants and crustaceans

    NARCIS (Netherlands)

    Charalambidou, I.; Santamaria, L.; Jansen, C.; Nolet, B.A.

    2005-01-01

    1. The consequences of plastic responses of the avian digestive tract for the potential of birds to disperse other organisms remain largely uninvestigated. 2. To explore how a seasonal diet switch in Mallard (Anas platyrhynchos L.) influences their potential to disperse plants and invertebrates, we

  13. Locomotion during digestion changes current estimates of seed dispersal kernels by fish

    NARCIS (Netherlands)

    Leeuwen, van C.H.A.; Beukeboom, R.; Nolet, B.A.; Bakker, E.S.; Pollux, B.J.A.

    2016-01-01

    1.Dispersal of seeds by animals is an important mechanism regulating plant diversity, range expansions and invasions. Many birds, mammals, fish and reptiles regularly ingest, transport and excrete viable seeds (known as endozoochory). 2.The effectiveness of endozoochory is modelled in dispersal

  14. 21 CFR 1240.65 - Psittacine birds.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Psittacine birds. 1240.65 Section 1240.65 Food and... DISEASES Specific Administrative Decisions Regarding Interstate Shipments § 1240.65 Psittacine birds. (a) The term psittacine birds shall include all birds commonly known as parrots, Amazons, Mexican double...

  15. Robird : a robotic bird of prey

    NARCIS (Netherlands)

    Folkertsma, Gerrit Adriaan; Straatman, Wessel; Nijenhuis, Nico; Venner, Cornelis H.; Stramigioli, Stefano

    2017-01-01

    Ever since the start of aviation, birds and airplanes have posed a mutual risk: Birds are killed when struck by aircraft, but, in return, bird strikes cause billions in damage to the aviation industry. Airports employ bird-control methods such as audiovisual deterrents (like scarecrows, lasers, and

  16. Territoriality, prospecting, and dispersal in cooperatively breeding Micronesian Kingfishers (Todiramphus cinnamominus reichenbachii)

    Science.gov (United States)

    Kesler, D.C.; Haig, S.M.

    2007-01-01

    We investigated territoriality, prospecting, and dispersal behavior in cooperatively breeding Pohnpei Micronesian Kingfishers (Todiramphus cinnamominus reichenbachii) throughout the annual cycle using radiotelemetry and color-band resights. Mean home-range size was 6.3 ha and territories were 8.1 ha. Within territories, Micronesian Kingfishers shared 63% of their home-range space with coterritorial occupants, and 3% was shared with extraterritorial conspecifics. Birds on cooperative territories had larger home ranges that overlapped more with coterritory occupants' home ranges than birds in pair-held territories. Despite evidence suggesting that resources necessary for survival and reproduction occurred on each territory, Micronesian Kingfishers of all age and sex classes made extraterritorial prospecting movements. Prospecting was rare; it comprised only 4.3% of our observations. When birds departed on forays, they were gone for ∼1.9 h and returned to home territories before sunset. Prospecting by dominant birds was temporally correlated with courtship and nest initiation, and birds were observed at neighboring nest sites with opposite-sex conspecifics during the period when females were available for fertilization. Juveniles and helpers prospected throughout the year and made repeated homesteading movements to dispersal destinations before dispersing. Mean dispersal distance for radiomarked individuals was 849 m. Results suggest that prospecting in Micronesian Kingfishers is a complex behavior that provides information for dispersal decisions and familiarity with dispersal destinations. Additionally, extraterritorial movements may provide covert opportunities for reproduction, which have potential to profoundly influence the distribution of fitness among helper and dominant Micronesian Kingfishers.

  17. [Leukosis in captive wild birds].

    Science.gov (United States)

    Loupal, G

    1984-10-01

    Among 2589 captive wild birds, examined between 1974 and 1983, we found leukosis in 26 birds belonging to 13 different species and five orders. We diagnosed lymphoid leukosis in 11 birds (two Melopsittacus undulatus, two Psittacus erithacus one Platycerus eximius, one Columba livia, one Streptopelia decaocto, one Polyplectron bicalcaratum, one Pavo cristatus, one Aptenodytes patachonia and one finch, species unknown), myeloid leukosis in 14 (nine Melopsittacus undulatus, two Agapomis personata fischeri, two Urgeainthus bengalus and one Neophemia pulchella) and stem cell leukosis in one bird (Serinus canaria). Among the cases with lymphoid leukosis we distinguished between lymphoblastic (four cases) and prolymphocytic forms (seven). Myeloid leukosis was subdivided into poorly differentiated (12 cases) and well differentiated myeloblastosis (two).

  18. 'WORLD OF BIRDS' WILDLIFE SANCTUARY

    African Journals Online (AJOL)

    The development and activities of the 'World of Birds' Wildlife. Sanctuary, near Cape Town, are .... For the time being the benefit for school outings will be mainly visual ... feed, sing, display, build nests, incubate, feed chicks - and even fight.

  19. Birds of the Mongol Empire

    OpenAIRE

    Eugene N. Anderson

    2016-01-01

    The Mongol Empire, the largest contiguous empire the world has ever known, had, among other things, a goodly number of falconers, poultry raisers, birdcatchers, cooks, and other experts on various aspects of birding. We have records of this, largely in the Yinshan Zhengyao, the court nutrition manual of the Mongol empire in China (the Yuan Dynasty). It discusses in some detail 22 bird taxa, from swans to chickens. The Huihui Yaofang, a medical encyclopedia, lists ten taxa used medicinally. Ma...

  20. 78 FR 53217 - Migratory Bird Hunting; Migratory Bird Hunting Regulations on Certain Federal Indian Reservations...

    Science.gov (United States)

    2013-08-28

    ..., and by what means such birds or any part, nest, or egg thereof may be taken, hunted, captured, killed... Service 50 CFR Part 20 Migratory Bird Hunting; Migratory Bird Hunting Regulations on Certain Federal...-FXMB1231099BPP0] RIN 1018-AY87 Migratory Bird Hunting; Migratory Bird Hunting Regulations on Certain Federal...

  1. 76 FR 19875 - Migratory Bird Hunting; Proposed 2011-12 Migratory Game Bird Hunting Regulations (Preliminary...

    Science.gov (United States)

    2011-04-08

    ..., carriage, or export of any * * * bird, or any part, nest, or egg'' of migratory game birds can take place... 50 CFR Part 20 Migratory Bird Hunting; Proposed 2011-12 Migratory Game Bird Hunting Regulations (Preliminary) With Requests for Indian Tribal Proposals and Requests for 2013 Spring and Summer Migratory Bird...

  2. Elena Natale ja Mikko Fritze: kultuuripealinna tiimi motivatsioon on töö ise / Elena Natale, Mikko Fritze ; intervjueerinud Tiina Saar

    Index Scriptorium Estoniae

    Natale, Elena

    2009-01-01

    SA Tallinn 2011 tegevjuht Mikko Fritze ja administratiivjuht Elena Natale vastavad küsimustele, mis puudutavad Eesti töökultuuri, , toimiva koostöö saavutamist meeskonnas, kasutatavaid motivatsiooni- ja juhtimissüsteeme, personalivalikut, majanduskriisi mõju SA Tallinn 2011 tegevusele

  3. Resilience and stability in bird guilds across tropical countryside

    Science.gov (United States)

    Karp, Daniel S.; Ziv, Guy; Zook, Jim; Ehrlich, Paul R.; Daily, Gretchen C.

    2011-01-01

    The consequences of biodiversity decline in intensified agricultural landscapes hinge on surviving biotic assemblages. Maintaining crucial ecosystem processes and services requires resilience to natural and anthropogenic disturbances. However, the resilience and stability of surviving biological communities remain poorly quantified. From a 10-y dataset comprising 2,880 bird censuses across a land-use gradient, we present three key findings concerning the resilience and stability of Costa Rican bird communities. First, seed dispersing, insect eating, and pollinating guilds were more resilient to low-intensity land use than high-intensity land use. Compared with forest assemblages, bird abundance, species richness, and diversity were all ∼15% lower in low-intensity land use and ∼50% lower in high-intensity land use. Second, patterns in species richness generally correlated with patterns in stability: guilds exhibited less variation in abundance in low-intensity land use than in high-intensity land use. Finally, interspecific differences in reaction to environmental change (response diversity) and possibly the portfolio effect, but not negative covariance of species abundances, conferred resilience and stability. These findings point to the changes needed in agricultural production practices in the tropics to better sustain bird communities and, possibly, the functional and service roles that they play. PMID:22160726

  4. Adaptive timing of detachment in a tick parasitizing hole-nesting birds.

    Science.gov (United States)

    White, J; Heylen, D J A; Matthysen, E

    2012-02-01

    In non-permanent parasites with low intrinsic mobility such as ticks, dispersal is highly dependent on host movements as well as the timing of separation from the hosts. Optimal detachment behaviour is all the more crucial in nidicolous ticks as the risk of detaching in non-suitable habitat is high. In this study, we experimentally investigated the detachment behaviour of Ixodes arboricola, a nidicolous tick that primarily infests birds roosting in tree-holes. We infested great tits with I. arboricola larvae or nymphs, and submitted the birds to 2 experimental treatments, a control treatment in which birds had normal access to nest boxes and an experimental treatment, in which the birds were prevented access to their nest boxes for varying lengths of time. In the control group, most ticks detached within 5 days, whereas in the experimental group, ticks remained on the bird for as long as the bird was prevented access (up to 14 days). This prolonged attachment caused a decrease in survival and engorgement weight in nymphs, but not in larvae. The capacity of I. arboricola larvae to extend the duration of attachment in non-suitable environments with no apparent costs, may be an adaptation to unpredictable use of cavities by roosting hosts during winter, and at the same time may facilitate dispersal of the larval instars.

  5. E.G. Jansen se rol in belang van die Afrikaners in Natal / P.J.J. Prinsloo

    OpenAIRE

    Prinsloo PJJ

    1987-01-01

    The purpose of this study is to analyse the extensive services delivered to the people in Natal by E.G. Jansen. This analysis also presents an image regarding the most important cultural achievements obtained by the Afrikaners in Natal, during the first half of the century. The necessity of this study lies in the fact that it analyses the fundamentals of the cultural awakening of the Afrikaners in Natal, during the first half of the century. The dominant British character of Natal is another ...

  6. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Northwest Arctic, Alaska: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for wading birds, shorebirds, waterfowl, raptors, diving birds, pelagic birds, and gulls/terns in Northwest...

  7. Annotated Bibliography of Bird Hazards to Aircraft: Bird Strike Committee Citations 1967-1997

    National Research Council Canada - National Science Library

    Short, Jeffrey

    1998-01-01

    .... This annotated bibliography of bird hazards to aircraft, termed ABBHA, is a compilation of citations with abstracts on a wide range of related topics such as bird strike tolerance engineering, bird...

  8. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Northern California: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for alcids, diving birds, gulls, terns, passerines, pelagic birds, raptors, shorebirds, wading birds, and...

  9. Birds as predators in tropical agroforestry systems.

    Science.gov (United States)

    Van Bael, Sunshine A; Philpott, Stacy M; Greenberg, Russell; Bichier, Peter; Barber, Nicholas A; Mooney, Kailen A; Gruner, Daniel S

    2008-04-01

    Insectivorous birds reduce arthropod abundances and their damage to plants in some, but not all, studies where predation by birds has been assessed. The variation in bird effects may be due to characteristics such as plant productivity or quality, habitat complexity, and/or species diversity of predator and prey assemblages. Since agroforestry systems vary in such characteristics, these systems provide a good starting point for understanding when and where we can expect predation by birds to be important. We analyze data from bird exclosure studies in forests and agroforestry systems to ask whether birds consistently reduce their arthropod prey base and whether bird predation differs between forests and agroforestry systems. Further, we focus on agroforestry systems to ask whether the magnitude of bird predation (1) differs between canopy trees and understory plants, (2) differs when migratory birds are present or absent, and (3) correlates with bird abundance and diversity. We found that, across all studies, birds reduce all arthropods, herbivores, carnivores, and plant damage. We observed no difference in the magnitude of bird effects between agroforestry systems and forests despite simplified habitat structure and plant diversity in agroforests. Within agroforestry systems, bird reduction of arthropods was greater in the canopy than the crop layer. Top-down effects of bird predation were especially strong during censuses when migratory birds were present in agroforestry systems. Importantly, the diversity of the predator assemblage correlated with the magnitude of predator effects; where the diversity of birds, especially migratory birds, was greater, birds reduced arthropod densities to a greater extent. We outline potential mechanisms for relationships between bird predator, insect prey, and habitat characteristics, and we suggest future studies using tropical agroforests as a model system to further test these areas of ecological theory.

  10. 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

  11. Maternal anxiety, risk factors and parenting in the first post-natal year.

    Science.gov (United States)

    Seymour, M; Giallo, R; Cooklin, A; Dunning, M

    2015-03-01

    The antecedents and consequences of maternal post-natal anxiety have received comparatively less attention than depression despite being one of the most frequently reported mental health difficulties experienced by parents following childbirth. The aim of this study was to extend emerging literature on post-natal anxiety by investigating the prevalence of maternal anxiety symptoms, and its relationship with parenting behaviours (i.e. warmth, hostility) and experiences (i.e. parenting efficacy and satisfaction) within the first post-natal year. The psychosocial risk factors for post-natal anxiety symptoms were also explored. A community sample of 224 Australian mothers of infants (aged 0-12 months) completed a self-report questionnaire. Mothers in the current sample reported significantly more symptoms of anxiety compared with a normative sample. Approximately 18% of mothers reported mild to extremely severe symptoms of anxiety, with a high proportion experiencing co-morbid depressive symptoms. Maternal anxiety was associated with low parenting warmth, involvement, efficacy and satisfaction, and high parenting hostility. Yet, co-morbid depression and anxiety was more strongly associated with these parenting behaviours and experiences than anxiety alone. A range of psychosocial risk factors (e.g. education, sleep, relationship quality) were associated with maternal post-natal anxiety symptoms, providing opportunities for early identification and targeted early intervention. © 2014 John Wiley & Sons Ltd.

  12. Birds and polycyclic aromatic hydrocarbons

    Science.gov (United States)

    Albers, P.H.

    2006-01-01

    Polycyclic aromatic hydrocarbons (PAH) are present throughout the global environment and are produced naturally and by activities of humans. Effects of PAH on birds have been determined by studies employing egg injection, egg immersion, egg shell application, single and multiple oral doses, subcutaneous injection, and chemical analysis of field-collected eggs and tissue. The four-to six-ring aromatic compounds are the most toxic to embryos, young birds, and adult birds. For embryos, effects include death, developmental abnormalities, and a variety of cellular and biochemical responses. For adult and young birds, effects include reduced egg production and hatching, increased clutch or brood abandonment, reduced growth, increased organweights, and a variety of biochemical responses. Trophic level accumulation is unlikely. Environmental exposure to PAH in areas of high human population or habitats affected by recent petroleum spills might be sufficient to adversely affect reproduction. Evidence of long-term effects of elevated concentrations of environmental PAH on bird populations is very limited and the mechanisms of effect are unclear.

  13. WT Bird. Bird collision recording for offshore wind farms

    Energy Technology Data Exchange (ETDEWEB)

    Wiggelinkhuizen, E.J.; Rademakers, L.W.M.M.; Barhorst, S.A.M. [ECN Wind Energy, Petten (Netherlands); Den Boon, H. [E-Connection Project, Bunnik (Netherlands); Dirksen, S. [Bureau Waardenburg, Culemborg (Netherlands); Schekkerman, H. [Alterra, Wageningen (Netherlands)

    2004-11-01

    A new method for monitoring of bird collisions has been developed using video and audio registrations that are triggered by sound and vibration measurements. Remote access to the recorded images and sounds makes it possible to count the number of collisions as well as to identify the species. After the successful proof of principle and evaluation on small land-based turbines the system is now being designed for offshore wind farms. Currently the triggering system and video and audio registration are being tested on large land-based wind turbines using bird dummies. Tests of three complete prototype systems are planned for 2005.

  14. WT-Bird. Bird collision recording for offshore wind farms

    Energy Technology Data Exchange (ETDEWEB)

    Wiggelinkhuizen, E.J.; Rademakers, L.W.M.M.; Barhorst, S.A.M. [ECN Wind Energy, Petten (Netherlands); Den Boon, H.J. [E-Connection Project, Bunnik (Netherlands); Dirksen, S. [Bureau Waardenburg, Culemborg (Netherlands); Schekkerman, H. [Alterra, Wageningen (Netherlands)

    2006-03-15

    A new method for registration of bird collisions has been developed using video cameras and microphones combined with event triggering by acoustic vibration measurement. Remote access to the recorded images and sounds makes it possible to count the number of collisions as well as to identify the species. Currently a prototype system is being tested on an offshore-scale land-based wind turbine using bird dummies. After these tests we planned to perform endurance tests on other land-based turbines under offshore-like conditions.

  15. Effects of drainage-basin geomorphology on insectivorous bird abundance in temperate forests.

    Science.gov (United States)

    Iwata, Tomoya; Urabe, Jotaro; Mitsuhashi, Hiromune

    2010-10-01

    Interfaces between terrestrial and stream ecosystems often enhance species diversity and population abundance of ecological communities beyond levels that would be expected separately from both the ecosystems. Nevertheless, no study has examined how stream configuration within a watershed influences the population of terrestrial predators at the drainage-basin scale. We examined the habitat and abundance relationships of forest insectivorous birds in eight drainage basins in a cool temperate forest of Japan during spring and summer. Each basin has different drainage-basin geomorphology, such as the density and frequency of stream channels. In spring, when terrestrial arthropod prey biomass is limited, insectivorous birds aggregated in habitats closer to streams, where emerging aquatic prey was abundant. Nevertheless, birds ceased to aggregate around streams in summer because terrestrial prey became plentiful. Watershed-scale analyses showed that drainage basins with longer stream channels per unit area sustained higher densities of insectivorous birds. Moreover, such effects of streams on birds continued from spring through summer, even though birds dispersed out of riparian areas in the summer. Although our data are from only a single year, our findings imply that physical modifications of stream channels may reduce populations of forest birds; thus, they emphasize the importance of landscape-based management approaches that consider both stream and forest ecosystems for watershed biodiversity conservation. © 2010 Society for Conservation Biology.

  16. Disease dynamics and bird migration--linking mallards Anas platyrhynchos and subtype diversity of the influenza A virus in time and space.

    Directory of Open Access Journals (Sweden)

    Gunnar Gunnarsson

    Full Text Available The mallard Anas platyrhynchos is a reservoir species for influenza A virus in the northern hemisphere, with particularly high prevalence rates prior to as well as during its prolonged autumn migration. It has been proposed that the virus is brought from the breeding grounds and transmitted to conspecifics during subsequent staging during migration, and so a better understanding of the natal origin of staging ducks is vital to deciphering the dynamics of viral movement pathways. Ottenby is an important stopover site in southeast Sweden almost halfway downstream in the major Northwest European flyway, and is used by millions of waterfowl each year. Here, mallards were captured and sampled for influenza A virus infection, and positive samples were subtyped in order to study possible links to the natal area, which were determined by a novel approach combining banding recovery data and isotopic measurements (δ(2H of feathers grown on breeding grounds. Geographic assignments showed that the core natal areas of studied mallards were in Estonia, southern and central Finland, and northwestern Russia. This study demonstrates a clear temporal succession of latitudes of natal origin during the course of autumn migration. We also demonstrate a corresponding and concomitant shift in virus subtypes. Acknowledging that these two different patterns were based in part upon different data, a likely interpretation worth further testing is that the early arriving birds with more proximate origins have different influenza A subtypes than the more distantly originating late autumn birds. If true, this knowledge would allow novel insight into the origins and transmission of the influenza A virus among migratory hosts previously unavailable through conventional approaches.

  17. Pre-natal and post-natal exposure to respiratory infection and atopic diseases development: a historical cohort study

    Directory of Open Access Journals (Sweden)

    Gehring Ulrike

    2006-05-01

    Full Text Available Abstract Background According to the hygiene hypothesis, infections in early life protect from allergic diseases. However, in earlier studies surrogate measures of infection rather than clinical infections were associated with decreased frequencies of atopic diseases. Exposure to infection indicating sub-clinical infection rather than clinical infection might protect from atopic diseases. Objective: to investigate whether exposure to acute respiratory infections within pregnancy and the first year of life is associated with atopic conditions at age 5–14 years and to explore when within pregnancy and the first year of life this exposure is most likely to be protective. Methods Historical cohort study: Population level data on acute respiratory infections from the routine reporting system of the former German Democratic Republic were linked with individual data from consecutive surveys on atopic diseases in the same region (n = 4672. Statistical analyses included multivariate logistic regression analysis and polynomial distributed lag models. Results High exposure to acute respiratory infection between pregnancy and age one year was associated with overall reduced odds of asthma, eczema, hay fever, atopic sensitization and total IgE. Exposure in the first 9 months of life showed the most pronounced effect. Adjusted odds ratio's for asthma, hay fever, inhalant sensitization and total IgE were statistical significantly reduced up to around half. Conclusion Exposure to respiratory infection (most likely indicating sub-clinical infection within pregnancy and the first year of life may be protective in atopic diseases development. The post-natal period thereby seems to be particularly important.

  18. Clock synchronization and dispersion

    International Nuclear Information System (INIS)

    Giovannetti, Vittorio; Lloyd, Seth; Maccone, Lorenzo; Wong, Franco N C

    2002-01-01

    We present a method to defeat effects of dispersion of timing signals when synchronizing clocks. It is based on the recently proposed 'conveyor belt synchronization' scheme and on the quantum dispersion cancellation effect

  19. Sex-biased dispersal at different geographical scales in a cooperative breeder from fragmented rainforest.

    Directory of Open Access Journals (Sweden)

    Carl Vangestel

    Full Text Available Dispersal affects both social behavior and population structure and is therefore a key determinant of long-term population persistence. However, dispersal strategies and responses to spatial habitat alteration may differ between sexes. Here we analyzed spatial and temporal variation in ten polymorphic microsatellite DNA loci of male and female Cabanis's greenbuls (Phyllastrephuscabanisi, a cooperative breeder of Afrotropical rainforest, to quantify rates of gene flow and fine-grained genetic structuring within and among fragmented populations. We found genetic evidence for female-biased dispersal at small spatial scales, but not at the landscape level. Local autocorrelation analysis provided evidence of positive genetic structure within 300 m distance ranges, which is consistent with behavioral observations of short-distance natal dispersal. At a landscape scale, individual-based autocorrelation values decreased over time while levels of admixture increased, possibly indicating increased gene flow over the past decade.

  20. Invasive alien birds in Denmark

    DEFF Research Database (Denmark)

    Fox, Anthony David; Heldbjerg, Henning; Nyegaard, Timme

    2015-01-01

    Avian Introduced Alien Species (IAS) constitute a threat to the integrity of native biodiversity, the economy and human health, so here we briefly review some of the problems posed by such species around the world in relation to such bird species in Denmark. A new European Union Regulation...... on Invasive Alien Species implemented in January 2015 establishes a framework for actions to combat alien species, which requires Member States to prevent the spread of alien species, provide early warning and rapid responses to their presence and management of established alien species where they occur. We...... show the importance of mechanisms such as DOF’s (Dansk Ornitologisk Forening, BirdLife Denmark) Atlas project, Common Bird Census (breeding and wintering species) and DOFbasen to contribute data on the current geographical and numerical distribution of the few serious alien avian species already...

  1. Invasive alien birds in Denmark

    DEFF Research Database (Denmark)

    Nyegaard, Timme; Heldbjerg, Henning; Fox, Anthony David

    Avian Introduced Alien Species (IAS) constitute a threat to the integrity of native biodiversity, the economy and human health, so here we briefly review some of the problems posed by such species around the world in relation to bird species in Denmark. A new European Union Regulation on Invasive...... Alien Species implemented in January 2015 requires a framework for actions to combat alien species, which requires Member States to prevent the spread of alien species, provide early warning and rapid responses to their presence and management of established alien species where they occur. We show...... the importance of mechanisms such as DOFs (Danish Ornithological Society, BirdLife Denmark) Atlas project, Common Bird Monitoring (breeding and wintering species) and DOFbasen to contribute data on the current geographical and numerical distribution of the few serious alien avian species already present...

  2. Dispersing powders in liquids

    CERN Document Server

    Nelson, RD

    1988-01-01

    This book provides powder technologists with laboratory procedures for selecting dispersing agents and preparing stable dispersions that can then be used in particle size characterization instruments. Its broader goal is to introduce industrial chemists and engineers to the phenomena, terminology, physical principles, and chemical considerations involved in preparing and handling dispersions on a commercial scale. The book introduces novices to: - industrial problems due to improper degree of dispersion; - the nomenclature used in describing particles; - the basic physica

  3. Fruit color preference by birds and applications to ecological restoration

    Directory of Open Access Journals (Sweden)

    B. L. Gagetti

    Full Text Available Abstract Ecological restoration aims to retrieve not only the structure but also the functionality of ecosystems. Frugivorous birds may play an important role in this process due to their efficiency in seed dispersal. Color perception in these animals is highly developed, and then the colors of fleshy fruits may provide important clues for choosing plant species for restoration plans. This study aims to integrate bird color preferences and restoration of degraded areas, with an objective to evaluate the potential attractiveness to birds by colored fruits. We carried out an experiment with 384 artificial fruits made of edible modeling clay with the following colors: black, blue, green and red, with 96 fruits of each color in six sites, including four restored areas and two second-growth forest fragments. We also tested the possible effect of light intensity on fruit consumption by color. A total of 120 (38.6% were assumed to be consumed by birds, and the fruit consumption varied in response to the location and light incidence. Consumption of black and blue fruits was not related to site by chance. Notwithstanding, red and black fruits were consumed significantly more than any other colors, emphasizing bird preference to these colors, regardless of location. Enrichment with shade tolerant shrubs or forest species with black or red fruits may be an alternative way to manage established restorations. In recently established or new restorations, one may introduce pioneer shrubs or short-lived forest species which have blue fruits, but also those having black or red ones.

  4. Chemical compass for bird navigation

    DEFF Research Database (Denmark)

    Solov'yov, Ilia; Hore, Peter J.; Ritz, Thorsten

    2014-01-01

    Migratory birds travel spectacular distances each year, navigating and orienting by a variety of means, most of which are poorly understood. Among them is a remarkable ability to perceive the intensity and direction of the Earth's magnetic field. Biologically credible mechanisms for the detection...... increased interest following the proposal in 2000 that free radical chemistry could occur in the bird's retina initiated by photoexcitation of cryptochrome, a specialized photoreceptor protein. In the present paper we review the important physical and chemical constraints on a possible radical...

  5. Fuglene. Audubon: Birds of America

    DEFF Research Database (Denmark)

    Schlichtkrull, Torsten

    2010-01-01

    The Royal Library owns one of the most exceptional works in book history, an original edition of John James Audubon Birds of America. This edition, in a format called “double elephant folio” was published from 1827 to 1838. On basis of existing literature, this article briefly describes the work...... the Royal Library and the University Library, joined the library cooperation of the 1800’s on an equal standing with the other two libraries. The Classen’s Library and the library’s founder, industrialist JF Classen are described briefly in this article. Due to two library mergers the Birds of America...

  6. Epidemiologic characterization of Colorado backyard bird flocks.

    Science.gov (United States)

    Smith, Emily I; Reif, John S; Hill, Ashley E; Slota, Katharine E; Miller, Ryan S; Bjork, Kathe E; Pabilonia, Kristy L

    2012-06-01

    Backyard gallinaceous bird flocks may play an important role in the spread of infectious diseases within poultry populations as well as the transmission of zoonotic diseases to humans. An epidemiologic characterization was conducted of Colorado backyard flocks to gather information on general flock characteristics, human movement of birds, human-bird interaction, biosecurity practices, and flock health. Our results suggest that backyard poultry flocks in Colorado are small-sized flocks (68.6% of flocks had meat or egg) production for the family (86.44%) or as pet or hobby birds (42.27%). The backyard flock environment may promote bird-to-bird transmission as well as bird-to-human transmission of infectious disease. Birds are primarily housed with free access to the outside (96.85%), and many are moved from the home premises (46.06% within 1 yr). Human contact with backyard flocks is high, biosecurity practices are minimal, and bird health is negatively impacted by increased movement events. Increased knowledge of backyard bird characteristics and associated management practices can provide guidelines for the development of measures to decrease disease transmission between bird populations, decrease disease transmission from birds to humans, and increase the overall health of backyard birds.

  7. Size-defined morphotypes in Zoanthus (Hexacorallia: Zoantharia) populations on shores in KwaZulu-Natal, South Africa.

    Science.gov (United States)

    Ryland, John S

    2015-07-17

    Colonial zoanthids are a conspicuous feature of the subtropical rocky intertidal in KwaZulu-Natal but those of the genus Zoanthus have a confused taxonomy with 10, difficult to separate, nominal species described from the region. This paper presents an analysis of polyp size, measured as mean diameter determined photographically from the number of polyps occupying an area of 6 × 4 cm(2). The results, based on diameter frequency of 127 samples from five shores, indicate three populations (morphotypes) with means of 4.3 (SD ±0.53), 5.7 (SD ±0.70) and 8.4 (SD ±0.58) mm occurring in the approximate abundance ratios of 10:5:1, possibly corresponding to Zoanthus sansibaricus, Z. natalensis and Z. lawrencei. The underlying assumptions with regard to population structure (the number, size and degree of fragmentation of clones) and the normality of data are discussed, as are trans-oceanic larval dispersal, recruitment, and genetic connectivity. The essential, traditional species description in Zoanthus, using internal morphology, on its own may be an inadequate discriminator of species. The status of the few possibly valid species is discussed in relation to the present results and recent studies based on the application of molecular genetics. Thorough studies of the population structure (genets and ramets) and a taxonomic approach based on the combined use of morphology, genetic methods and statistically robust, quantitative morphometrics are proposed as a potential way forward.

  8. East Africa's diminishing bird habitats and bird species

    African Journals Online (AJOL)

    foreign exchange earnings for each national exchequer. However, recent national census records have .... Dar-es-. Salaam: Wildlife Conservation Society of Tanzania. Bennun, L & Njoroge, P. 1999. Important Bird Areas in Kenya, Nairobi: East Africa Natural. History Society. Byaruhanga, A, Kasoma, P. & Pomeroy, D. 2001.

  9. A Case Report of Gender Dysphoria with Morbid Jealousy in a Natal Female

    Science.gov (United States)

    Rao, G. Prasad; Aparna, B.

    2017-01-01

    Gender dysphoria is a new entity introduced in the Diagnostic and Statistical Manual of Mental Disorder V to address the distress of the previously labeled gender identity disorder patients. It is less commonly seen in natal females, often starting in their childhood. Adults and adolescent natal females with early-onset gender dysphoria are almost always gynephilic. This case report is presented to discuss the interesting evolution of the symptoms in gender dysphoria case with difficulties in adjusting to the assigned sexual role, relationship problems, morbid jealousy, and severe depressive features with suicidal ideations. PMID:29284816

  10. A experiência do homem como acompanhante no cuidado pré-natal

    OpenAIRE

    Miriam Aparecida de Abreu Cavalcante

    2007-01-01

    A presença de acompanhante no pré-natal é uma prática adotada e estimulada em alguns serviços de saúde. Este estudo teve como objetivo compreender a experiência do parceiro, como acompanhante de sua esposa/companheira nas consultas de pré-natal em uma instituição filantrópica da cidade de São Paulo. Trata-se de uma pesquisa qualitativa, cujos dados foram coletados por meio de entrevistas semi-estruturadas, organizados pelo método do discurso do sujeito coletivo e analisados pela ótica da Teor...

  11. Seed dispersal networks in the Galápagos and the consequences of alien plant invasions

    DEFF Research Database (Denmark)

    Heleno, R. H.; Olesen, Jens Mogens; Nogales, M.

    2013-01-01

    Alien plants are a growing threat to the Gala´pagos unique biota. We evaluated the impact of alien plants on eight seed dispersal networks from two islands of the archipelago. Nearly 10 000 intact seeds from 58 species were recovered from the droppings of 18 bird and reptile dispersers. The most......, followed by small ground finch, two mockingbirds, the giant tortoise and two insectivorous birds. Most animals dispersed alien seeds, but these formed a relatively small proportion of the interactions. Nevertheless, the integration of aliens was higher in the island that has been invaded for longest......, suggesting a time-lag between alien plant introductions and their impacts on seed dispersal networks. Alien plants become more specialized with advancing invasion, favouring more simplified plant and disperser communities. However, only habitat type significantly affected the overall network structure. Alien...

  12. Theory of dispersive microlenses

    Science.gov (United States)

    Herman, B.; Gal, George

    1993-01-01

    A dispersive microlens is a miniature optical element which simultaneously focuses and disperses light. Arrays of dispersive mircolenses have potential applications in multicolor focal planes. They have a 100 percent optical fill factor and can focus light down to detectors of diffraction spot size, freeing up areas on the focal plane for on-chip analog signal processing. Use of dispersive microlenses allows inband color separation within a pixel and perfect scene registration. A dual-color separation has the potential for temperature discrimination. We discuss the design of dispersive microlenses and present sample results for efficient designs.

  13. Vegetation composition and structure influences bird species ...

    African Journals Online (AJOL)

    Vegetation composition and structure influences bird species community ... variables on bird species diversity and richness of respective foraging guilds, and ... of the species assessed: (1) increasing closed cover due to woody plant density, ...

  14. Evaluation of three oil spill laboratory dispersant effectiveness tests

    International Nuclear Information System (INIS)

    Sullivan, D.; Farlow, J.; Sahatjian, K.A.

    1993-01-01

    Chemical dispersants can be used to reduce the interfacial tension of floating oil slicks so that the oils disperse more rapidly into the water column and thus pose less of a threat to shorelines, birds, and marine mammals. The laboratory test currently specified in federal regulations to measure dispersant effectiveness is not especially easy or inexpensive, and generates a rather large quantity of oily waste water. This paper describes the results of an effort by the EPA to identify a more suitable laboratory dispersant effectiveness test. EPA evaluated three laboratory methods: the Revised Standard Dispersant Effectiveness Test currently used (and required by regulation) in the United States, the swirling flask test (developed by Environment Canada), and the IFP-dilution test (used in france and other European countries). Six test oils and three dispersants were evaluated; dispersants were applied to the oil at an average 1:10 ratio (dispersant to oil) for each of the three laboratory methods. Screening efforts were used to focus on the most appropriate oil/dispersant combination for detailed study. A screening criterion was established that required a combination that gave at least 20% effectiveness results. The selected combination turned out to be Prudhoe Bay crude oil and the dispersant Corexit 9527. This combination was also most likely to be encountered in US coastal waters. The EPA evaluation concluded that the three tests gave similar precision results, but that the swirling flask test was fastest, cheapest, simplest, and required least operator skill. Further, EPA is considering conducting the dispersant effectiveness test itself, rather than having data submitted by a dispersant manufacturer, and establishing an acceptability criterion (45% efficiency) which would have to be met before a dispersant could be placed on the Product Schedule of the National Contingency Plan (NCP)

  15. Pre‐natal undernutrition and post‐natal overnutrition are associated with permanent changes in hepatic metabolism markers and fatty acid composition in sheep

    DEFF Research Database (Denmark)

    Hou, L.; Hellgren, Lars; Kongsted, A. H.

    2014-01-01

    was associated with increased hepatic triglyceride, ceramide and free fatty acid content in adulthood (not observed in lambs), which was accompanied by up‐regulated early‐stage insulin signalling as reflected by increased INSRβ and PI3K‐p110 protein expression. The HCHF diet increased hepatic triglyceride...... content in lambs, associated with down‐regulated expressions of energy‐metabolism‐related genes (GLUT1, PPARα, SREBP1c, PEPCK). These post‐natal effects were not observed in adult HCHF sheep, after they had received a moderate (body‐fat correcting) diet for 1.5 years. Interestingly, pre‐natal LOW...... nutrition induced permanent alterations in hepatic phospholipids’ fatty acid composition. Thus, the amount of linoleic acid (C18 : 2 ∆9,12) was significantly increased and composition of rumen‐derived fatty acids were altered, indicating changed composition of rumenal microbiota. Hepatic insulin signalling...

  16. Palaearctic-African Bird Migration

    DEFF Research Database (Denmark)

    Iwajomo, Soladoye Babatola

    Bird migration has attracted a lot of interests over past centuries and the methods used for studying this phenomenon has greatly improved in terms of availability, dimension, scale and precision. In spite of the advancements, relatively more is known about the spring migration of trans-Saharan m......Bird migration has attracted a lot of interests over past centuries and the methods used for studying this phenomenon has greatly improved in terms of availability, dimension, scale and precision. In spite of the advancements, relatively more is known about the spring migration of trans...... of birds from Europe to Africa and opens up the possibility of studying intra-African migration. I have used long-term, standardized autumn ringing data from southeast Sweden to investigate patterns in biometrics, phenology and population trends as inferred from annual trapping totals. In addition, I...... in the population of the species. The papers show that adult and juvenile birds can use different migration strategies depending on time of season and prevailing conditions. Also, the fuel loads of some individuals were theoretically sufficient for a direct flight to important goal area, but whether they do so...

  17. Physiological adaptation in desert birds

    NARCIS (Netherlands)

    Williams, JB; Tieleman, BI; Williams, Joseph B.

    We call into question the idea that birds have not evolved unique physiological adaptations to desert environments. The rate at which desert larks metabolize energy is lower than in mesic species within the same family, and this lower rate of living translates into a lower overall energy requirement

  18. Millipedes (Diplopoda) in birds' nests

    Czech Academy of Sciences Publication Activity Database

    Tajovský, Karel; Mock, A.; Krumpál, M.

    2001-01-01

    Roč. 37, - (2001), s. 321-323 ISSN 1164-5563 Institutional research plan: CEZ:AV0Z6066911 Keywords : bird s nest s * microsites * millipedes Subject RIV: EH - Ecology, Behaviour Impact factor: 0.317, year: 2001

  19. Notes on some Sumatran birds

    NARCIS (Netherlands)

    Junge, G.C.A.

    1948-01-01

    During the war I was able to identify some collections of birds from Sumatra, present in the Leiden Museum. These collections were brought together by E. Jacobson and W. C. van Heurn in the Padang Highlands in 1013; by W. Groeneveldt in the same area in 1914 and 1915; bij L. P. Cosquino de Bussy and

  20. Microbiology as if Bird Watching

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 10. Microbiology as if Bird Watching. Milind G Watve. Classroom Volume 1 Issue 10 October 1996 pp 78-81. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/001/10/0078-0081. Author Affiliations.

  1. Bird Flight and Satish Dhawan

    Indian Academy of Sciences (India)

    and birds has inspired poetry, art, l~terature, science and tech- nology. In Monsoon, Wilbur ... Henk Tennekes, an aerospace engineering professor at Pennsyl- vania State University, USA, has a different story to tell in his popular book The ...

  2. Birds and Bird Habitat: What Are the Risks from Industrial Wind Turbine Exposure?

    Science.gov (United States)

    Sprague, Terry; Harrington, M. Elizabeth; Krogh, Carmen M. E.

    2011-01-01

    Bird kill rate and disruption of habitat has been reported when industrial wind turbines are introduced into migratory bird paths or other environments. While the literature could be more complete regarding the documentation of negative effects on birds and bird habitats during the planning, construction, and operation of wind power projects,…

  3. 76 FR 32224 - Migratory Birds; Take of Migratory Birds by the Armed Forces

    Science.gov (United States)

    2011-06-03

    ... DEPARTMENT OF THE INTERIOR Fish and Wildlife Service Migratory Birds; Take of Migratory Birds by... Forces to incidentally take migratory birds during approved military readiness activities without violating the Migratory Bird Treaty Act (MBTA). The Authorization Act provided this interim authority to...

  4. 76 FR 59298 - Migratory Bird Hunting; Migratory Bird Hunting Regulations on Certain Federal Indian Reservations...

    Science.gov (United States)

    2011-09-26

    ... such birds or any part, nest, or egg thereof may be taken, hunted, captured, killed, possessed, sold...-0014; 91200-1231-9BPP-L2] RIN 1018-AX34 Migratory Bird Hunting; Migratory Bird Hunting Regulations on... Service, Interior. ACTION: Final rule. SUMMARY: This rule prescribes special late-season migratory bird...

  5. The Physics of Bird Flight: An Experiment

    Science.gov (United States)

    Mihail, Michael D.; George, Thomas F.; Feldman, Bernard J.

    2008-01-01

    This article describes an experiment that measures the forces acting on a flying bird during takeoff. The experiment uses a minimum of equipment and only an elementary knowledge of kinematics and Newton's second law. The experiment involves first digitally videotaping a bird during takeoff, analyzing the video to determine the bird's position as a…

  6. DNA barcoding of Dutch birds

    Directory of Open Access Journals (Sweden)

    Mansour Aliabadian

    2013-12-01

    Full Text Available The mitochondrial cytochrome c-oxidase subunit I (COI can serve as a fast and accurate marker for the identification of animal species, and has been applied in a number of studies on birds. We here sequenced the COI gene for 387 individuals of 147 species of birds from the Netherlands, with 83 species being represented by >2 sequences. The Netherlands occupies a small geographic area and 95% of all samples were collected within a 50 km radius from one another. The intraspecific divergences averaged 0.29% among this assemblage, but most values were lower; the interspecific divergences averaged 9.54%. In all, 95% of species were represented by a unique barcode, with 6 species of gulls and skua (Larus and Stercorariusat least one shared barcode. This is best explained by these species representing recent radiations with ongoing hybridization. In contrast, one species, the Lesser Whitethroat Sylvia curruca showed deep divergences, averaging 5.76% and up to 8.68% between individuals. These possibly represent two distinct taxa, S. curruca and S. blythi, both clearly separated in a haplotype network analysis. Our study adds to a growing body of DNA barcodes that have become available for birds, and shows that a DNA barcoding approach enables to identify known Dutch bird species with a very high resolution. In addition some species were flagged up for further detailed taxonomic investigation, illustrating that even in ornithologically well-known areas such as the Netherlands, more is to be learned about the birds that are present.

  7. High Emigration Propensity and Low Mortality on Transfer Drives Female-Biased Dispersal of Pyriglena leucoptera in Fragmented Landscapes.

    Directory of Open Access Journals (Sweden)

    Marcelo Awade

    Full Text Available Dispersal is a biological process performed in three stages: emigration, transfer and immigration. Intra-specific variation on dispersal behavior, such as sex-bias, is very common in nature, particularly in birds and mammals. However, dispersal is difficult to measure in the field and many hypotheses concerning the causes of sex-biased dispersal remain without empirical confirmation. An important limitation of most empirical studies is that inferences about sex-biased dispersal are based only on emigration proneness or immigration success data. Thus, we still do not know whether sex-biased immigration in fragmented landscapes occurs during emigration, transfer or in both stages. We conducted translocation and radiotracking experiments to assess i whether inter-patch dispersal movements of a rainforest bird (Pyriglena leucoptera is sex-biased and ii how dispersal stages and the perceptual range of the individuals are integrated to generate dispersal patterns. Our results showed that inter-patch dispersal is sex-biased at all stages for P. leucoptera, as females not only exhibit a higher emigration propensity but are subjected to a lower risk of predation when moving through the matrix. Moreover, our data support a perceptual range of 80 m and our results showed that dispersal success decreases considerably when inter-patch distances exceeds this perceptual range. In this case, birds have a higher probability of travelling over longer routes and, as a consequence, the risk of predation increases, specially for males. Overall, results supported that assuming dispersal as a single-stage process to describe dispersal behavior may be misleading. In this way, our study advanced our understanding of processes and patterns related to inter-patch dispersal of neotropical forest birds, shedding light on potential implications for population dynamics and for the management of fragmented landscapes.

  8. Mopeia Virus-related Arenavirus in Natal Multimammate Mice, Morogoro, Tanzania

    DEFF Research Database (Denmark)

    Günther, Stephan; Hoofd, Guy; Charrel, Remi

    2009-01-01

    A serosurvey involving 2,520 small mammals from Tanzania identified a hot spot of arenavirus circulation in Morogoro. Molecular screening detected a new arenavirus in Natal multimammate mice (Mastomys natalensis), Morogoro virus, related to Mopeia virus. Only a small percentage of mice carry Moro...

  9. Riga-Fede Disease Associated with Natal Teeth: Two Different Approaches in the Same Case

    Directory of Open Access Journals (Sweden)

    Luiz Evaristo Ricci Volpato

    2015-01-01

    Full Text Available Natal teeth are those present in the oral cavity at the child’s birth. These teeth can cause ulcers on the ventral surface of the tongue, lip, and the mother’s breast characterizing the Riga-Fede Disease. The treatment depends on the tooth’s mobility and the risk of aspiration or swallowing; whether it is supernumerary or regular primary teeth; whether it is causing interference in breastfeeding; breast and oral soft tissue injuries; and the general state of child’s health. A 1-month-old female infant was diagnosed with two natal teeth and an ulcerated lesion on the ventral surface of the tongue, leading to the clinical diagnosis of Riga-Fede Disease. The treatment performed consisted of the maintenance of the natal tooth that showed no increased mobility, adding a small increment of glass ionomer cement to its incisal edge, and orientation for hygiene with saline solution. Due to the increased mobility of the other natal tooth, surgical removal was performed. There was regular monitoring of the patient and complete wound healing was observed after 15 days. The proposed treatment was successful and the patient is still in follow-up without recurrence of the lesion after one year.

  10. Before harbour construction, Richards Bay on the Kwa- Zulu-Natal ...

    African Journals Online (AJOL)

    spamer

    Zulu-Natal coast (28°47´S, 32°05´E) was a shallow, subtropical estuary of approximately 30 km2 (3 000 ha) surface area (Begg 1978), consisting of a large basin. (lagoon) connected to the Indian Ocean through a narrow mouth north of the basin. The shallow, con- stricted mouth substantially reduced the tidal range.

  11. On the occurrence of Stenopus tenui- rostris De Man, 1888 in Natal ...

    African Journals Online (AJOL)

    Department of Biology, Texas A & M University, College. Station, Texas 77843, USA. S. Koslowski c/o Durban Corporation, Durban. Received 8 JQlluary 1990; accepted 5 March 1990. The stenopodidean shrimp Slenopus lenuiroslris De Man,. 1888 is reported from Natal waters for the first time. This record represents a ...

  12. HIV/AIDS Stigma Attitudes among Educators in KwaZulu-Natal, South Africa

    Science.gov (United States)

    Chao, Li-Wei; Gow, Jeff; Akintola, Goke; Pauly, Mark

    2010-01-01

    Background: One hundred and twenty educators from KwaZulu-Natal, South Africa, underwent HIV/AIDS training. The educators were surveyed about their attitudes toward people with HIV. Methods: The educators completed self-administered survey questionnaires both before and after 2 interventions. Measures included demographic characteristics,…

  13. A study of feeding in some inshore reef fish of the Natal Coast, South ...

    African Journals Online (AJOL)

    A detailed quantitative investigation of the feeding habits of seven important Natal inshore ... limits of influence of the surf zone or shore break. The physical features of .... There is a tendency for juvenile N. JithophiJus to form larger shoals than ...

  14. Fire scar mapping for disaster response in KwaZulu-Natal South ...

    African Journals Online (AJOL)

    This study assessed the potential of the new Landsat 8 multispectral imagery in rapidly mapping fire scars to aid disaster management response teams in emergency efforts. Maximum likelihood and iso cluster algorithms where used to classify burnt and unburnt areas in KwaZulu-Natal, South Africa. The Landsat 8 sensor ...

  15. Civilisation and Colonial Education: Natal and Western Australia in the 1860s in Comparative Perspective

    Science.gov (United States)

    Swartz, Rebecca

    2018-01-01

    This paper examines how two Britons, working in Western Australia and Natal, respectively, engaged with ideas about the civilisation and education of Indigenous people. It is argued that concepts of civilisation were debated by missionaries, researchers and members of the public. Using the correspondence, publications and private journals of two…

  16. Stomach contents of some shore-caught teleosts of Natal, South Mrica

    African Journals Online (AJOL)

    1985-09-25

    Sep 25, 1985 ... Natal nearshore substratum were visually analysed for percentage composition. Commonly caught fish, namely. Rhabdosargus sarba, R. holubi, Pomadasys commersonni,. Trachinotus african us and T. bot/a, were opportunistic omnivorous predators and fed largely on sand mussels and benthic crustacea.

  17. Mercury concentrations at a historically mercury-contaminated site in KwaZulu-Natal, South Africa

    CSIR Research Space (South Africa)

    Williams, CR

    2011-02-01

    Full Text Available A mercury (Hg) processing plant previously operating in KwaZulu-Natal Province (South Africa) discharged Hg waste into a nearby river system causing widespread contamination since the 1980s. Although the processing plant ceased operation in the 1990...

  18. Vegetation change in northern KwaZulu-Natal since the Anglo-Zulu ...

    African Journals Online (AJOL)

    The quality of the landscape is declining in many grassland and savanna areas of Africa as a consequence of woody plant encroachment. We investigated the changes in vegetation at selected sites on the battlefields of the Anglo-Zulu War of 1879 in KwaZulu-Natal. We used fixed-point repeat photographs to compare the ...

  19. Hunger for Knowledge: Food Insecurity among Students at the University of KwaZulu-Natal

    Science.gov (United States)

    Munro, Nicholas; Quayle, Michael; Simpson, Heather; Barnsley, Shelley

    2013-01-01

    The experience of food insecurity in the South African university student population is not well documented or researched. Data to assess vulnerability to food insecurity in a sample of 1.083 students from the University of KwaZulu-Natal (Pietermaritzburg Campus) was collected between 2007 and 2010 via a questionnaire developed specifically for…

  20. The rabbit as an animal model for post-natal vitreous matrix differentiation and degeneration

    NARCIS (Netherlands)

    Los, L. I.

    2008-01-01

    Purpose This study evaluates whether rabbits are a suitable animal model to study post-natal vitreous differentiation and degeneration. Methods Human and rabbit eyes of various ages were studied by complementary anatomical techniques, light microscopy, and transmission electron microscopy. Results

  1. Structure and precursors of the 1992 / 93 drought in KwaZulu-Natal ...

    African Journals Online (AJOL)

    The historical context and potential causes and structure of the 1992/93 drought in KwaZulu-Natal are analysed using NCEP reanalysis data. The analysis indicates that increased westerly winds with surface marine lows and continental highs prevailed over Southern Africa. Anomalous divergence and subsidence occur ...

  2. Sharks caught in the protective gill nets off KwaZulu-Natal, South ...

    African Journals Online (AJOL)

    Between 1980 and 2001, a total of 661 African angel sharks Squatina africana was caught in the protective nets off KwaZulu-Natal, South Africa. The mean annual catch was 30 sharks (range = 11–69, SD = 12.4), with no trend in catch rate over the study period. Individuals were caught throughout the year and through ...

  3. Sharks caught in the protective gill nets off KwaZulu-Natal, South ...

    African Journals Online (AJOL)

    Between 1978 and 1999, a total of 5 626 dusky sharks Carcharhinus obscurus, constituting 20% of the total shark catch, was caught in the protective nets off KwaZulu-Natal, South Africa. The mean annual catch was 256 sharks (SD = 107.5, range 129–571). There was no significant linear trend in catch rate with time.

  4. Sharks caught in the KwaZulu-Natal bather protection programme ...

    African Journals Online (AJOL)

    The current study provides long-term catch rate and biological data for tiger sharks Galeocerdo cuvier caught in the KwaZulu-Natal bather protection programme. Between 1978 and 2014, 1 760 G. cuvier were caught in nets and between 2007 and 2014, 108 G. cuvier were caught on drumlines. Standardised catch rates ...

  5. The Post-Natal Development of the Reproductive Tract of the ...

    African Journals Online (AJOL)

    The Post-Natal Development of the Reproductive Tract of the Springbok Ram Lamb Antidorcas Marsupialis Marsupialis Zimmermann. JD Skinner, J. H. M. Van Zyl. Abstract. A search of the literature has not revealed any reference to the development of the reproductive tract of the male springbok or any quantitative studies ...

  6. Flood frequency analysis at ungauged sites in the KwaZulu-Natal ...

    African Journals Online (AJOL)

    Use of the index-flood method at ungauged sites requires methods for estimation of the index-flood parameter at these sites. This study attempts to relate the mean annual flood to site characteristics of catchments in KwaZulu-Natal, South Africa. The ordinary, weighted and generalised least square methods for estimating ...

  7. Assessment of the state of the estuaries of the Cape and Natal in 1985/86

    CSIR Research Space (South Africa)

    Heydorn, AEF

    1986-08-01

    Full Text Available During a meeting of the South African National Committee for Oceanographic Research (SANCOR) Estuaries Programme Committee held on 12 and 13 October 1983 at San Lameer, Natal, consideration was given to a working paper on the freshwater requirements...

  8. Identifying regional landscapes for conservation planning: a case study from KwaZulu-Natal, South Africa

    CSIR Research Space (South Africa)

    Fairbanks, DHK

    2000-08-30

    Full Text Available , and the landscape structure and processes that maintain patterns of biodiversity. The authors have developed a method of classifying landscapes for the KwaZulu-Natal province of South Africa. The process entailed the use of 1 km grid data from climate and terrain...

  9. Invasive alien plants in the terrestrial ecosystems of Natal, South Africa

    CSIR Research Space (South Africa)

    Macdonald, IAW

    1985-01-01

    Full Text Available This report consists of two types of chapters. Most of the chapters are short syntheses of particular aspects of the alien plant problem in Natal, written by groups of participants during the workshop meeting. They are brief accounts of the state...

  10. Flood frequency analysis at ungauged sites in the KwaZulu-Natal Province, South Africa

    DEFF Research Database (Denmark)

    Kjeldsen, Thomas Rodding; Smithers, J.C.; Schulze, R.E.

    2001-01-01

    Use of the index-flood method at ungauged sites requires methods for estimation of the index-flood parameter at these sites. This study attempts to relate the mean annual flood to site characteristics of catchments in KwaZulu-Natal, South Africa. The ordinary, weighted and generalised least square...

  11. HIV Incidence Remains High in KwaZulu-Natal, South Africa: Evidence from Three Districts

    NARCIS (Netherlands)

    Nel, Annaléne; Mabude, Zonke; Smit, Jenni; Kotze, Philip; Arbuckle, Derek; Wu, Jian; van Niekerk, Neliëtte; van de Wijgert, Janneke

    2012-01-01

    Background: HIV prevalence and incidence among sexually active women in peri-urban areas of Ladysmith, Edendale, and Pinetown, KwaZulu-Natal, South Africa, were assessed between October 2007 and February 2010 in preparation for vaginal microbicide trials. Methodology/Principal Findings: Sexually

  12. Circulation of shelf waters in the KwaZulu-Natal Bight, South Africa ...

    African Journals Online (AJOL)

    Ship-based acoustic Doppler current profiler (S-ADCP) technology, used in survey mode, has enabled nearsynoptic views of the in situ 3-D current field in the KwaZulu-Natal (KZN) Bight to be elucidated for the first time. Data acquired by the research vessels RS Africana and RS Algoa in June 2005, September 2007, March ...

  13. Non-School Influences and Educational Disadvantage: Pre and Post-natal Nutritional Deprivation

    Science.gov (United States)

    Doll, Russell C.

    1973-01-01

    Deals with pre and post-natal malnutrition and its possible influence on the child, focusing on these points: How wide-spread and severe is the malnutrition? What might be the effects of the malnutrition at certain critical points in development? (Author/JM)

  14. Training teacher-librarians in KwaZulu Natal | Hoskins | Innovation

    African Journals Online (AJOL)

    The Advanced Certificate in Education School Library Development and Management at the University of KwaZulu-Natal was started in 2004 to train teacher-librarians. A preliminary study was done to investigate the status of school libraries in the schools from which the educators came and the use of information and ...

  15. Exploring Teachers' Practices in Teaching Mathematics and Statistics in Kwazulu-Natal Schools

    Science.gov (United States)

    Umugiraneza, Odette; Bansilal, Sarah; North, Delia

    2017-01-01

    Teaching approaches and assessment practices are key factors that contribute to the improvement of learner outcomes. The study on which this article is based, explored the methods used by KwaZulu-Natal (KZN) teachers in teaching and assessing mathematics and statistics. An instrument containing closed and open-ended questions was distributed to…

  16. Overview of the KwaZulu-Natal sardine run | van der Lingen | African ...

    African Journals Online (AJOL)

    This paper provides an introduction to, and overview of, the natural phenomenon known as the KwaZulu-Natal sardine run. Previous literature on this topic and hypotheses about the reasons why, and the mechanisms how, the run occurs are briefly synthesised and described. Papers contributing to this suite that detail more ...

  17. Socio-economic implications of the KwaZulu-Natal sardine run for ...

    African Journals Online (AJOL)

    The economic and social effects of the annual sardine run on the indigenous community on the south coast of KwaZulu-Natal, South Africa, were assessed using data gathered from questionnaires and personal interviews with 329 members of the community. Their knowledge, perceptions and attitudes about the sardine run ...

  18. Pre-natal effects of ethanol and folic acid supplements on the ...

    African Journals Online (AJOL)

    Pre-natal effects of ethanol and folic acid supplements on the mineralisation of bones in ... folic acid deficiency, in particular at pregnancy; thus inflicting severe skeletal ... or 'catch-up' growth was displayed in the ethanol plus folate treated rats.

  19. Nesting bird "host funnel" increases mosquito-bird contact rate.

    Science.gov (United States)

    Caillouët, Kevin A; Riggan, Anna E; Bulluck, Lesley P; Carlson, John C; Sabo, Roy T

    2013-03-01

    Increases in vector-host contact rates can enhance arbovirus transmission intensity. We investigated weekly fluctuations in contact rates between mosquitoes and nesting birds using the recently described Nest Mosquito Trap (NMT). The number of mosquitoes per nestling increased from nesting season. Our evidence suggests the coincidence of the end of the avian nesting season and increasing mosquito abundances may have caused a "host funnel," concentrating host-seeking mosquitoes to the few remaining nestlings. The relative abundance of mosquitoes collected by the NMT suggests that significantly more Aedes albopictus (Skuse) and Culex pipiens (L.) /restuans (Theobald) sought nesting bird bloodmeals than were predicted by their relative abundances in CO2-baited Centers for Disease Control and Prevention light and gravid traps. Culex salinarius (Coquillett) and Culex erraticus Dyar and Knab were collected in NMTs in proportion to their relative abundances in the generic traps. Temporal host funnels and nesting bird host specificity may enhance arbovirus amplification and explain observed West Nile virus and St. Louis encephalitis virus amplification periods.

  20. Mapping global diversity patterns for migratory birds.

    Directory of Open Access Journals (Sweden)

    Marius Somveille

    Full Text Available Nearly one in five bird species has separate breeding and overwintering distributions, and the regular migrations of these species cause a substantial seasonal redistribution of avian diversity across the world. However, despite its ecological importance, bird migration has been largely ignored in studies of global avian biodiversity, with few studies having addressed it from a macroecological perspective. Here, we analyse a dataset on the global distribution of the world's birds in order to examine global spatial patterns in the diversity of migratory species, including: the seasonal variation in overall species diversity due to migration; the contribution of migratory birds to local bird diversity; and the distribution of narrow-range and threatened migratory birds. Our analyses reveal a striking asymmetry between the Northern and Southern hemispheres, evident in all of the patterns investigated. The highest migratory bird diversity was found in the Northern Hemisphere, with high inter-continental turnover in species composition between breeding and non-breeding seasons, and extensive regions (at high latitudes where migratory birds constitute the majority of the local avifauna. Threatened migratory birds are concentrated mainly in Central and Southern Asia, whereas narrow-range migratory species are mainly found in Central America, the Himalayas and Patagonia. Overall, global patterns in the diversity of migratory birds indicate that bird migration is mainly a Northern Hemisphere phenomenon. The asymmetry between the Northern and Southern hemispheres could not have easily been predicted from the combined results of regional scale studies, highlighting the importance of a global perspective.

  1. Urban Bird Feeding: Connecting People with Nature.

    Directory of Open Access Journals (Sweden)

    Daniel T C Cox

    Full Text Available At a time of unprecedented biodiversity loss, researchers are increasingly recognizing the broad range of benefits provided to humankind by nature. However, as people live more urbanized lifestyles there is a progressive disengagement with the natural world that diminishes these benefits and discourages positive environmental behaviour. The provision of food for garden birds is an increasing global phenomenon, and provides a readily accessible way for people to counter this trend. Yet despite its popularity, quite why people feed birds remains poorly understood. We explore three loosely defined motivations behind bird feeding: that it provides psychological benefits, is due to a concern about bird welfare, and/or is due to a more general orientation towards nature. We quantitatively surveyed households from urban towns in southern England to explore attitudes and actions towards garden bird feeding. Each household scored three Likert statements relating to each of the three motivations. We found that people who fed birds regularly felt more relaxed and connected to nature when they watched garden birds, and perceived that bird feeding is beneficial for bird welfare while investing time in minimising associated risks. Finally, feeding birds may be an expression of a wider orientation towards nature. Overall, we found that the feelings of being relaxed and connected to nature were the strongest drivers. As urban expansion continues both to threaten species conservation and to change peoples' relationship with the natural world, feeding birds may provide an important tool for engaging people with nature to the benefit of both people and conservation.

  2. Green Light for Nocturnally Migrating Birds

    Directory of Open Access Journals (Sweden)

    Hanneke Poot

    2008-12-01

    Laboratory experiments have shown the magnetic compass to be wavelength dependent: migratory birds require light from the blue-green part of the spectrum for magnetic compass orientation, whereas red light (visible long-wavelength disrupts magnetic orientation. We designed a field study to test if and how changing light color influenced migrating birds under field conditions. We found that nocturnally migrating birds were disoriented and attracted by red and white light (containing visible long-wavelength radiation, whereas they were clearly less disoriented by blue and green light (containing less or no visible long-wavelength radiation. This was especially the case on overcast nights. Our results clearly open perspective for the development of bird-friendly artificial lighting by manipulating wavelength characteristics. Preliminary results with an experimentally developed bird-friendly light source on an offshore platform are promising. What needs to be investigated is the impact of bird-friendly light on other organisms than birds.

  3. Genetic insights into dispersal distance and disperser fitness of African lions (Panthera leo) from the latitudinal extremes of the Kruger National Park, South Africa.

    Science.gov (United States)

    van Hooft, Pim; Keet, Dewald F; Brebner, Diana K; Bastos, Armanda D S

    2018-04-03

    Female lions generally do not disperse far beyond their natal range, while males can disperse distances of over 200 km. However, in bush-like ecosystems dispersal distances less than 25 km are reported. Here, we investigate dispersal in lions sampled from the northern and southern extremes of Kruger National Park, a bush-like ecosystem in South Africa where bovine tuberculosis prevalence ranges from low to high across a north-south gradient. A total of 109 individuals sampled from 1998 to 2004 were typed using 11 microsatellite markers, and mitochondrial RS-3 gene sequences were generated for 28 of these individuals. Considerable north-south genetic differentiation was observed in both datasets. Dispersal was male-biased and generally further than 25 km, with long-distance male gene flow (75-200 km, detected for two individuals) confirming that male lions can travel large distances, even in bush-like ecosystems. In contrast, females generally did not disperse further than 20 km, with two distinctive RS-3 gene clusters for northern and southern females indicating no or rare long-distance female dispersal. However, dispersal rate for the predominantly non-territorial females from southern Kruger (fraction dispersers ≥0.68) was higher than previously reported. Of relevance was the below-average body condition of dispersers and their low presence in prides, suggesting low fitness. Large genetic differences between the two sampling localities, and low relatedness among males and high dispersal rates among females in the south, suggestive of unstable territory structure and high pride turnover, have potential implications for spread of diseases and the management of the Kruger lion population.

  4. Genetic diversity and sex-bias dispersal of plateau pika in Tibetan plateau.

    Science.gov (United States)

    Zhang, Liangzhi; Qu, Jiapeng; Li, Kexin; Li, Wenjing; Yang, Min; Zhang, Yanming

    2017-10-01

    Dispersal is an important aspect in organism's life history which could influence the rate and outcome of evolution of organism. Plateau pika is the keystone species in community of grasslands in Tibetan Plateau. In this study, we combine genetic and field data to character the population genetic pattern and dispersal dynamics in plateau pika ( Ochotona curzoniae ). Totally, 1,352 individual samples were collected, and 10 microsatellite loci were analyzed. Results revealed that plateau pika possessed high genetic diversity and inbreeding coefficient in a fine-scale population. Dispersal distance is short and restricted in about 20 m. An effective sex-biased dispersal strategy is employed by plateau pika: males disperse in breeding period for mating while females do it after reproduction for offspring and resource. Inbreeding avoiding was shown as the common driving force of dispersal, together with the other two factors, environment and resource. In addition, natal dispersal is female biased. More detailed genetic analyzes are needed to confirm the role of inbreeding avoidance and resource competition as ultimate cause of dispersal patterns in plateau pika.

  5. Sibship effects on dispersal behaviour in a pre-industrial human population.

    Science.gov (United States)

    Nitsch, A; Lummaa, V; Faurie, C

    2016-10-01

    Understanding dispersal behaviour and its determinants is critical for studies on life-history maximizing strategies. Although many studies have investigated the causes of dispersal, few have focused on the importance of sibship, despite that sibling interactions are predicted to lead to intrafamilial differences in dispersal patterns. Using a large demographic data set from pre-industrial Finland (n = 9000), we tested whether the sex-specific probability of dispersal depended on the presence of same-sex or opposite-sex elder siblings who can both compete and cooperate in the family. Overall, following our predictions, the presence of same-sex elder siblings increased the probability of dispersal from natal population for both sexes, whereas the number of opposite-sex siblings had less influence. Among males, dispersal was strongly linked to access to land resources. Female dispersal was mainly associated with competition over availability of mates but likely mediated by competition over access to wealthy mates rather mate availability per se. Besides ecological constraints, sibling interactions are strongly linked with dispersal decisions and need to be better considered in the studies on the evolution of family dynamics and fitness maximizing strategies in humans and other species. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

  6. The birds of Blyth Harbour

    International Nuclear Information System (INIS)

    Still, D.; Carver, H.; Little, B.; Lawrence, S.G.

    1995-01-01

    Blyth Harbour Wind Farm, constructed upon an exposed pier, is not a Site of Special Scientific Interest and is designated to become a RAMSAR location because of the presence of a significant population of the Purple Sandpiper. A study of the effect of the wind farm on the birds was started before the wind farm was constructed and is ongoing. Initial evidence of how the wind turbines have affected the 110 varieties of birds recorded within the harbour will be presented and compared to previous research carried out in Europe and the USA. Methodology has included intensive beach surveys, visits to wind farms in the UK and USA and consultations with wildlife advisory bodies. The study will continue until 1996. (Author)

  7. Tick-borne pathogens in ticks collected from birds in Taiwan

    Directory of Open Access Journals (Sweden)

    Chi-Chien Kuo

    2017-11-01

    Full Text Available Abstract Background A variety of human diseases transmitted by arthropod vectors, including ticks, are emerging around the globe. Birds are known to be hosts of ticks and can disperse exotic ticks and tick-borne pathogens. In Taiwan, previous studies have focused predominantly on mammals, leaving the role of birds in the maintenance of ticks and dissemination of tick-borne pathogens undetermined. Methods Ticks were collected opportunistically when birds were studied from 1995 to 2013. Furthermore, to improve knowledge on the prevalence and mean load of tick infestation on birds in Taiwan, ticks were thoroughly searched for when birds were mist-netted at seven sites between September 2014 and April 2016 in eastern Taiwan. Ticks were identified based on both morphological and molecular information and were screened for potential tick-borne pathogens, including the genera Anaplasma, Babesia, Borrelia, Ehrlichia and Rickettsia. Finally, a list of hard tick species collected from birds in Taiwan was compiled based on past work and the current study. Results Nineteen ticks (all larvae were recovered from four of the 3096 unique mist-netted bird individuals, yielding a mean load of 0.006 ticks/individual and an overall prevalence of 0.13%. A total of 139 ticks from birds, comprising 48 larvae, 35 nymphs, 55 adults and one individual of unknown life stage, were collected from 1995 to 2016, and 11 species of four genera were identified, including three newly recorded species (Haemaphysalis wellingtoni, Ixodes columnae and Ixodes turdus. A total of eight tick-borne pathogens were detected, with five species (Borrelia turdi, Anaplasma sp. clone BJ01, Ehrlichia sp. BL157-9, Rickettsia helvetica and Rickettsia monacensis not previously isolated in Taiwan. Overall, 16 tick species of five genera have been recorded feeding on birds, including nine species first discovered in this study. Conclusion Our study demonstrates the paucity of information on ticks of

  8. Saving our shared birds: Partners in Flight tri-national vision for landbird conservation

    Science.gov (United States)

    Berlanga, Humberto; Kennedy, Judith A.; Rich, Terrell D.; Arizmendi, Maria del Coro; Beardmore, Carol J.; Blancher, Peter J.; Butcher, Gregory S.; Couturier, Andrew R.; Dayer, Ashley A.; Demarest, Dean W.; Easton, Wendy E.; Gustafson, Mary; Iñigo-Elias, Eduardo E.; Krebs, Elizabeth A.; Panjabi, Arvind O.; Rodriguez Contreras, Vicente; Rosenberg, Kenneth V.; Ruth, Janet M.; Santana Castellon, Eduardo; Vidal, Rosa Ma.; Will, Tom

    2010-01-01

    Landbirds are the most abundant and diverse group of birds in North America, with nearly 900 species distributed across every major terrestrial habitat. Birds are indicators of environmental health; their populations track changes in habitat, water, disease, and climate. They are providers of invaluable ecosystem services, such as pest control, seed dispersal, and pollination. As the focus of bird watching, they help generate billions of dollars for national economies. Yet, we are in danger of losing this spectacular and irreplaceable bird diversity: landbirds are experiencing significant declines, ominous threats, and shrinking habitats across a continent with growing human populations, increasing resource consumption, and changing climate. Saving Our Shared Birds presents for the first time a comprehensive conservation assessment of landbirds in Canada, Mexico, and the continental United States. This new tri-national vision encompasses the complete range of many migratory species and highlights the vital links among migrants and highly threatened resident species in Mexico. It points to a set of continent-scale actions necessary to maintain the landbird diversity and abundance that are our shared responsibility. This collaborative effort of Partners in Flight (PIF) is the next step in linking the countries of the Western Hemisphere to help species at risk and keep common birds common through voluntary partnerships—our mission since 1990. Saving Our Shared Birds builds upon PIF’s 2004 North American Landbird Conservation Plan, which presented science-based priorities for the conservation of 448 landbird species in Canada and the United States. Our three nations have expressed their commitment to cooperative conservation through numerous international treaties, agreements, and programs, including formation of the North American Bird Conservation Initiative (NABCI) a decade ago. The NABCI partnership recognizes that effective conservation requires a concerted

  9. Comparative Phylogeography of Neotropical Birds

    Science.gov (United States)

    2009-05-01

    birds, butterflies, plants , soil type, and precipitation (Whitmore and Prance 1987); (C) study populations based largely on neo-tropical lowland...Caballero, A. 1994. Developments in the prediction of effective population size. Heredity 73:657- 679. Camargo, A., R. O. De Sa, and W. R. Heyer. 2006...157-183. Hamrick, J. L., and M. J. W. Godt. 1996. Effects of life history traits on genetic diversity in plant species. Philosophical Transactions Of

  10. Freeing Maya Angelou's Caged Bird

    OpenAIRE

    Graham, Joyce L.

    1991-01-01

    This study involves a comprehensive examination of one book, Maya Angelou's autobiographical I Know Why Why the Caged Bird Sings, since it was first published in 1970. Recognized as an important literary work, the novel is used in many middle and secondary school classrooms throughout the united States. Additionally, the work often is challenged in public schools on the grounds of its sexual and/or racial content. The purpose of this study included establishing th...

  11. Winter Responses of Forest Birds to Habitat Corridors and Gaps

    Directory of Open Access Journals (Sweden)

    Colleen Cassady St. Clair

    1998-12-01

    Full Text Available Forest fragmentation and habitat loss may disrupt the movement or dispersal of forest-dwelling birds. Despite much interest in the severity of these effects and ways of mitigating them, little is known about actual movement patterns in different habitat types. We studied the movement of wintering resident birds, lured by playbacks of mobbing calls, to compare the willingness of forest birds to travel various distances in continuous forest, along narrow corridors (fencerows, and across gaps in forest cover. We also quantified the willingness of Black-capped Chickadees (Poecile atricapillus to cross gaps when alternative forested detour routes were available. All species were less likely to respond to the calls as distance increased to 200 m, although White-breasted Nuthatches (Sitta carolinensis and Hairy Woodpeckers (Picoides villosus were generally less likely to respond than chickadees and Downy Woodpeckers (P. pubescens. Chickadees were as likely to travel in corridors as in continuous forest, but were less likely to cross gaps as the gap distance increased. The other species were less willing to travel in corridors and gaps relative to forest, and the differences among habitats also increased with distance. For chickadees, gap-crossing decisions in the presence of forested detours varied over the range of distances that we tested, and were primarily influenced by detour efficiency (the length of the shortcut relative to the available detour. Over short distances, birds used forested detours, regardless of their efficiency. As absolute distances increased, birds tended to employ larger shortcuts in the open when detour efficiency was low or initial distance in the open was high, but they limited their distance from the nearest forest edge to 25 m. Thus, chickadees were unwilling to cross gaps of > 50 m when they had forested alternatives, yet they sometimes crossed gaps as large as 200 m when no such choice existed. Our results suggest that

  12. Functional and phylogenetic structure of island bird communities.

    Science.gov (United States)

    Si, Xingfeng; Cadotte, Marc W; Zeng, Di; Baselga, Andrés; Zhao, Yuhao; Li, Jiaqi; Wu, Yiru; Wang, Siyu; Ding, Ping

    2017-05-01

    Biodiversity change in anthropogenically transformed habitats is often nonrandom, yet the nature and importance of the different mechanisms shaping community structure are unclear. Here, we extend the classic Theory of Island Biogeography (TIB) to account for nonrandom processes by incorporating species traits and phylogenetic relationships into a study of faunal relaxation following habitat loss and fragmentation. Two possible mechanisms can create nonrandom community patterns on fragment islands. First, small and isolated islands might consist of similar or closely related species because they are environmentally homogeneous or select for certain shared traits, such as dispersal ability. Alternatively, communities on small islands might contain more dissimilar or distantly related species than on large islands because limited space and resource availability result in greater competitive exclusion among species with high niche overlap. Breeding birds were surveyed on 36 islands and two mainland sites annually from 2010 to 2014 in the Thousand Island Lake region, China. We assessed community structure of breeding birds on these subtropical land-bridge islands by integrating species' trait and evolutionary distances. We additionally analysed habitat heterogeneity and variance in size ratios to distinguish biotic and abiotic processes of community assembly. Results showed that functional-phylogenetic diversity increased with island area, and decreased with isolation. Bird communities on the mainland were more diverse and generally less clustered than island bird communities and not different than randomly assembled communities. Bird communities on islands tend to be functionally similar and phylogenetically clustered, especially on small and isolated islands. The nonrandom decline in species diversity and change in bird community structure with island area and isolation, along with the relatively homogeneous habitats on small islands, support the environmental

  13. Bird Responses to Lowland Rainforest Conversion in Sumatran Smallholder Landscapes, Indonesia.

    Science.gov (United States)

    Prabowo, Walesa Edho; Darras, Kevin; Clough, Yann; Toledo-Hernandez, Manuel; Arlettaz, Raphael; Mulyani, Yeni A; Tscharntke, Teja

    2016-01-01

    Rapid land-use change in the tropics causes dramatic losses in biodiversity and associated functions. In Sumatra, Indonesia, lowland rainforest has mainly been transformed by smallholders into oil palm (Elaeis guineensis) and rubber (Hevea brasiliensis) monocultures, interspersed with jungle rubber (rubber agroforests) and a few forest remnants. In two regions of the Jambi province, we conducted point counts in 32 plots of four different land-use types (lowland rainforest, jungle rubber, rubber plantation and oil palm plantation) as well as in 16 nearby homegardens, representing a small-scale, traditional agricultural system. We analysed total bird abundance and bird abundance in feeding guilds, as well as species richness per point count visit, per plot, and per land-use system, to unveil the conservation importance and functional responses of birds in the different land-use types. In total, we identified 71 species from 24 families. Across the different land-use types, abundance did not significantly differ, but both species richness per visit and per plot were reduced in plantations. Feeding guild abundances between land-use types were variable, but homegardens were dominated by omnivores and granivores, and frugivorous birds were absent from monoculture rubber and oil palm. Jungle rubber played an important role in harbouring forest bird species and frugivores. Homegardens turned out to be of minor importance for conserving birds due to their low sizes, although collectively, they are used by many bird species. Changes in functional composition with land-use conversion may affect important ecosystem functions such as biological pest control, pollination, and seed dispersal. In conclusion, maintaining forest cover, including degraded forest and jungle rubber, is of utmost importance to the conservation of functional and taxonomic bird diversity.

  14. Spatio-temporal dynamics of global H5N1 outbreaks match bird migration patterns

    Directory of Open Access Journals (Sweden)

    Yali Si

    2009-11-01

    Full Text Available The global spread of highly pathogenic avian influenza H5N1 in poultry, wild birds and humans, poses a significant pandemic threat and a serious public health risk. An efficient surveillance and disease control system relies on the understanding of the dispersion patterns and spreading mechanisms of the virus. A space-time cluster analysis of H5N1 outbreaks was used to identify spatio-temporal patterns at a global scale and over an extended period of time. Potential mechanisms explaining the spread of the H5N1 virus, and the role of wild birds, were analyzed. Between December 2003 and December 2006, three global epidemic phases of H5N1 influenza were identified. These H5N1 outbreaks showed a clear seasonal pattern, with a high density of outbreaks in winter and early spring (i.e., October to March. In phase I and II only the East Asia Australian flyway was affected. During phase III, the H5N1 viruses started to appear in four other flyways: the Central Asian flyway, the Black Sea Mediterranean flyway, the East Atlantic flyway and the East Africa West Asian flyway. Six disease cluster patterns along these flyways were found to be associated with the seasonal migration of wild birds. The spread of the H5N1 virus, as demonstrated by the space-time clusters, was associated with the patterns of migration of wild birds. Wild birds may therefore play an important role in the spread of H5N1 over long distances. Disease clusters were also detected at sites where wild birds are known to overwinter and at times when migratory birds were present. This leads to the suggestion that wild birds may also be involved in spreading the H5N1 virus over short distances.

  15. Bird Responses to Lowland Rainforest Conversion in Sumatran Smallholder Landscapes, Indonesia

    Science.gov (United States)

    Clough, Yann; Toledo-Hernandez, Manuel; Arlettaz, Raphael; Mulyani, Yeni A.; Tscharntke, Teja

    2016-01-01

    Rapid land-use change in the tropics causes dramatic losses in biodiversity and associated functions. In Sumatra, Indonesia, lowland rainforest has mainly been transformed by smallholders into oil palm (Elaeis guineensis) and rubber (Hevea brasiliensis) monocultures, interspersed with jungle rubber (rubber agroforests) and a few forest remnants. In two regions of the Jambi province, we conducted point counts in 32 plots of four different land-use types (lowland rainforest, jungle rubber, rubber plantation and oil palm plantation) as well as in 16 nearby homegardens, representing a small-scale, traditional agricultural system. We analysed total bird abundance and bird abundance in feeding guilds, as well as species richness per point count visit, per plot, and per land-use system, to unveil the conservation importance and functional responses of birds in the different land-use types. In total, we identified 71 species from 24 families. Across the different land-use types, abundance did not significantly differ, but both species richness per visit and per plot were reduced in plantations. Feeding guild abundances between land-use types were variable, but homegardens were dominated by omnivores and granivores, and frugivorous birds were absent from monoculture rubber and oil palm. Jungle rubber played an important role in harbouring forest bird species and frugivores. Homegardens turned out to be of minor importance for conserving birds due to their low sizes, although collectively, they are used by many bird species. Changes in functional composition with land-use conversion may affect important ecosystem functions such as biological pest control, pollination, and seed dispersal. In conclusion, maintaining forest cover, including degraded forest and jungle rubber, is of utmost importance to the conservation of functional and taxonomic bird diversity. PMID:27224063

  16. Bird Responses to Lowland Rainforest Conversion in Sumatran Smallholder Landscapes, Indonesia.

    Directory of Open Access Journals (Sweden)

    Walesa Edho Prabowo

    Full Text Available Rapid land-use change in the tropics causes dramatic losses in biodiversity and associated functions. In Sumatra, Indonesia, lowland rainforest has mainly been transformed by smallholders into oil palm (Elaeis guineensis and rubber (Hevea brasiliensis monocultures, interspersed with jungle rubber (rubber agroforests and a few forest remnants. In two regions of the Jambi province, we conducted point counts in 32 plots of four different land-use types (lowland rainforest, jungle rubber, rubber plantation and oil palm plantation as well as in 16 nearby homegardens, representing a small-scale, traditional agricultural system. We analysed total bird abundance and bird abundance in feeding guilds, as well as species richness per point count visit, per plot, and per land-use system, to unveil the conservation importance and functional responses of birds in the different land-use types. In total, we identified 71 species from 24 families. Across the different land-use types, abundance did not significantly differ, but both species richness per visit and per plot were reduced in plantations. Feeding guild abundances between land-use types were variable, but homegardens were dominated by omnivores and granivores, and frugivorous birds were absent from monoculture rubber and oil palm. Jungle rubber played an important role in harbouring forest bird species and frugivores. Homegardens turned out to be of minor importance for conserving birds due to their low sizes, although collectively, they are used by many bird species. Changes in functional composition with land-use conversion may affect important ecosystem functions such as biological pest control, pollination, and seed dispersal. In conclusion, maintaining forest cover, including degraded forest and jungle rubber, is of utmost importance to the conservation of functional and taxonomic bird diversity.

  17. Broadening our approaches to studying dispersal in raptors

    Science.gov (United States)

    Morrison, J.L.; Wood, P.B.

    2009-01-01

    Dispersal is a behavioral process having consequences for individual fitness and population dynamics. Recent advances in technology have spawned new theoretical examinations and empirical studies of the dispersal process in birds, providing opportunities for examining how this information may be applied to studies of the dispersal process in raptors. Many raptors are the focus of conservation efforts; thus, reliable data on all aspects of a species' population dynamics, including dispersal distances, movement rates, and mortality rates of dispersers, are required for population viability analyses that are increasingly used to inform management. Here, we address emerging issues and novel approaches used in the study of avian dispersal, and provide suggestions to consider when developing and implementing studies of dispersal in raptors. Clarifying study objectives is essential for selection of an appropriate methodology and sample size needed to obtain accurate estimates of movement distances and rates. Identifying an appropriate study-area size will allow investigators to avoid underestimating population connectivity and important population parameters. Because nomadic individuals of some species use temporary settling areas or home ranges before breeding, identification of these areas is critical for conservation efforts focusing on habitats other than breeding sites. Study designs for investigating raptor dispersal also should include analysis of environmental and social factors influencing dispersal, to improve our understanding of condition-dependent dispersal strategies. Finally, we propose a terminology for use in describing the variety of movements associated with dispersal behavior in raptors, and we suggest this terminology could be used consistently to facilitate comparisons among studies. ?? 2009 The Raptor Research Foundation, Inc.

  18. Dispersal of forest insects

    Science.gov (United States)

    Mcmanus, M. L.

    1979-01-01

    Dispersal flights of selected species of forest insects which are associated with periodic outbreaks of pests that occur over large contiguous forested areas are discussed. Gypsy moths, spruce budworms, and forest tent caterpillars were studied for their massive migrations in forested areas. Results indicate that large dispersals into forested areas are due to the females, except in the case of the gypsy moth.

  19. Improved new generation dispersants

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    The use of dispersants to combat oil spills has attracted controversy over the years, and there has been a number of accusations of the chemicals involved doing more harm than good. A new study by the International Petroleum Industry Environmental Conservation Association discusses the positive and the negatives of dispersant use to be considered when drawing up spill contingency plans. (author)

  20. Seed dispersal in fens

    Science.gov (United States)

    Middleton, B.; Van Diggelen, R.; Jensen, K.

    2006-01-01

    Question: How does seed dispersal reduce fen isolation and contribute to biodiversity? Location: European and North American fens. Methods: This paper reviews the literature on seed dispersal to fens. Results: Landscape fragmentation may reduce dispersal opportunities thereby isolating fens and reducing genetic exchange. Species in fragmented wetlands may have lower reproductive success, which can lead to biodiversity loss. While fens may have always been relatively isolated from each other, they have become increasingly fragmented in modern times within agricultural and urban landscapes in both Europe and North America. Dispersal by water, animals and wind has been hampered by changes related to development in landscapes surrounding fens. Because the seeds of certain species are long-lived in the seed bank, frequent episodes of dispersal are not always necessary to maintain the biodiversity of fens. However, of particular concern to restoration is that some dominant species, such as the tussock sedge Carex stricta, may not disperse readily between fens. Conclusions: Knowledge of seed dispersal can be used to maintain and restore the biodiversity of fens in fragmented landscapes. Given that development has fragmented landscapes and that this situation is not likely to change, the dispersal of seeds might be enhanced by moving hay or cattle from fens to damaged sites, or by reestablishing lost hydrological connections. ?? IAVS; Opulus Press.

  1. Individual dispersal delays in a cooperative breeder: Ecological constraints, the benefits of philopatry and the social queue for dominance.

    Science.gov (United States)

    Nelson-Flower, Martha J; Wiley, Elizabeth M; Flower, Tom P; Ridley, Amanda R

    2018-03-20

    Delayed dispersal is a key step in the evolution of familial animal societies and cooperative breeding. However, no consensus has been reached on the ecological and social circumstances driving delayed dispersal. Here, we test predictions from the ecological constraints and benefits of philopatry hypotheses as well as the recently proposed dual benefits hypothesis to better understand the evolution of group-living and cooperative breeding. Furthermore, we consider how individual social circumstances within groups affect dispersal decisions. We examine 11 years of life-history information on a wild population of cooperatively breeding southern pied babblers Turdoides bicolor. We investigate the effects of ecological conditions, natal-group membership and individual social context on male and female dispersal delays, disperser survival and acquisition of dominance. Female dispersal decisions are generally unconstrained by ecological or social circumstances. In contrast, males disperse in response to relaxed ecological constraints, decreases in nepotistic tolerance or when low social rank in the queue for dominance decreases their likelihood of gaining a dominant breeding position. Early dispersal by end-of-queue males often leads to a head-of-queue subordinate position in a non-natal group, thereby increasing access to dominant breeding positions. However, males and females remaining in natal groups gain benefits of philopatry via increased survival and, for head-of-queue males, very high likelihood of acquisition of a breeding position. Overall, predictions from the dual benefits hypothesis best describe these results, while some predictions from each of the ecological constraints and benefits of philopatry hypotheses were supported. The benefits of living and working together (collective action benefits) in large stable groups are of central importance in shaping dispersal delays in southern pied babbler societies. In addition, position in the subordinate social

  2. Genetic detection of sex-specific dispersal in historical and contemporary populations of anadromous brown trout Salmo trutta

    DEFF Research Database (Denmark)

    Bekkevold, Dorte; Hansen, Michael Møller; Mensberg, Karen-Lise Dons

    2004-01-01

    The study of sex-biased dispersal has attracted considerable attention in birds and mammals, but less in other taxa, including fishes. We analysed sex-specific dispersal in historical (1910s and 1950s) and contemporary (1990s) samples of anadromous brown trout Salmo trutta. We tested the hypothesis...... that dispersal is unbiased using information from microsatellite DNA and applying an assignment index for 11 temporally and spatially separated samples. Our results are most consistent with brown trout dispersal being male biased, and provide no evidence of female bias. We found no evidence that dispersal...

  3. Evidence for an association between post-fledging dispersal and microsatellite multilocus heterozygosity in a large population of greater flamingos.

    Directory of Open Access Journals (Sweden)

    Mark A F Gillingham

    Full Text Available Dispersal can be divided into three stages: departure, transience and settlement. Despite the fact that theoretical studies have emphasized the importance of heterozygosity on dispersal strategies, empirical evidence of its effect on different stages of dispersal is lacking. Here, using multi-event capture-mark-recapture models, we show a negative association between microsatellite multilocus heterozygosity (MLH; 10 loci; n = 1023 and post-fledging dispersal propensity for greater flamingos, Phoenicopterus roseus, born in southern France. We propose that the negative effects of inbreeding depression affects competitive ability and therefore more homozygous individuals are more likely to disperse because they are less able to compete within the highly saturated natal site. Finally, a model with the effect of MLH on propensity of post-fledgling dispersers to disperse to the long-distance sites of Africa was equivalent to the null model, suggesting that MLH had low to no effect on dispersal distance. Variations in individual genetic quality thus result in context-dependent heterogeneity in dispersal strategies at each stage of dispersal. Our results have important implications on fitness since sites visited early in life are known to influence site selection later on in life and future survival.

  4. Epidemiologic study of anisometropia in students of Natal, Brazil Estudo epidemiológico da anisometropia em estudantes da cidade de Natal, Brasil

    Directory of Open Access Journals (Sweden)

    Carlos Alexandre de Amorim Garcia

    2005-02-01

    Full Text Available PURPOSE: To perform an epidemiologic study in students in Natal/Brazil, with relation to refractional anisometropia, evaluating criteria such as: gender, age, and association with strabismus and amblyopia. METHODS: A study of 1,024 students randomly selected from several districts of Natal/Brazil was undertaken by the Department of Ophthalmology of the Federal University of Rio Grande do Norte (UFRN, observing the following criteria of > 2 spherical or cylindrical diopter refractional anisometropia relating it to sex, age, association with strabismus, amblyopia and anisometropia classification. RESULTS: We found a prevalence of 2% (N=21 anisometropia in the students. The female gender predominated with 81% (N=17. In students with anisometropia, we observed an association with strabismus in 9.5% of cases (N=2, both with exotropia. The association of anisometropia with amblyopia occurred in 47.6% of the cases (N=10, with 8 cases of unilateral amblyopia and 2 cases of bilateral amblyopia. CONCLUSIONS: There was a predominance of anisometropia in females, and an increased prevalence of strabismus and amblyopia in students with anisometropia.OBJETIVO: Realizar um estudo epidemiológico em estudantes de Natal/Brasil, com relação à anisometropia refracional, avaliando os seguintes critérios: sexo, idade e associação com estrabismo e ambliopia. MÉTODOS: Foram estudados 1.024 estudantes, randomicamente selecionados, pertencentes aos diversos distritos da cidade de Natal/Brasil, pelo Departamento de Oftalmologia, da Universidade Federal do Rio Grande do Norte (UFRN, observando os seguintes aspectos, quanto à anisometropia > 2 dioptrias esférica ou cilíndrica, sexo, idade, associação com estrabismo e ambliopia, e os tipos de anisometropia. RESULTADOS: Encontrou-se prevalência de anisometropia de 2% (N=21 nos estudantes. O sexo feminino predominou com 81% (N=17. Nos estudantes com anisometropia, observou-se associação com estrabismo em 9

  5. Wild bird surveillance for highly pathogenic avian influenza H5 in North America

    Science.gov (United States)

    Flint, Paul L.; Pearce, John M.; Franson, J. Christian; Derksen, Dirk V.

    2015-01-01

    It is unknown how the current Asian origin highly pathogenic avian influenza H5 viruses arrived, but these viruses are now poised to become endemic in North America. Wild birds harbor these viruses and have dispersed them at regional scales. What is unclear is how the viruses may be moving from the wild bird reservoir into poultry holdings. Active surveillance of live wild birds is likely the best way to determine the true distribution of these viruses. We also suggest that sampling be focused on regions with the greatest risk for poultry losses and attempt to define the mechanisms of transfer to enhance biosecurity. Responding to the recent outbreaks of highly pathogenic avian influenza in North America requires an efficient plan with clear objectives and potential management outcomes.

  6. Dispersal and metapopulation stability

    Directory of Open Access Journals (Sweden)

    Shaopeng Wang

    2015-10-01

    Full Text Available Metapopulation dynamics are jointly regulated by local and spatial factors. These factors may affect the dynamics of local populations and of the entire metapopulation differently. Previous studies have shown that dispersal can stabilize local populations; however, as dispersal also tends to increase spatial synchrony, its net effect on metapopulation stability has been controversial. Here we present a simple metapopulation model to study how dispersal, in interaction with other spatial and local processes, affects the temporal variability of metapopulations in a stochastic environment. Our results show that in homogeneous metapopulations, the local stabilizing and spatial synchronizing effects of dispersal cancel each other out, such that dispersal has no effect on metapopulation variability. This result is robust to moderate heterogeneities in local and spatial parameters. When local and spatial dynamics exhibit high heterogeneities, however, dispersal can either stabilize or destabilize metapopulation dynamics through various mechanisms. Our findings have important theoretical and practical implications. We show that dispersal functions as a form of spatial intraspecific mutualism in metapopulation dynamics and that its effect on metapopulation stability is opposite to that of interspecific competition on local community stability. Our results also suggest that conservation corridors should be designed with appreciation of spatial heterogeneities in population dynamics in order to maximize metapopulation stability.

  7. Using landscape ecology to test hypotheses about large-scale abundance patterns in migratory birds

    Science.gov (United States)

    Flather, C.H.; Sauer, J.R.

    1996-01-01

    The hypothesis that Neotropical migrant birds may be undergoing widespread declines due to land use activities on the breeding grounds has been examined primarily by synthesizing results from local studies. Growing concern for the cumulative influence of land use activities on ecological systems has heightened the need for large-scale studies to complement what has been observed at local scales. We investigated possible landscape effects on Neotropical migrant bird populations for the eastern United States by linking two large-scale inventories designed to monitor breeding-bird abundances and land use patterns. The null hypothesis of no relation between landscape structure and Neotropical migrant abundance was tested by correlating measures of landscape structure with bird abundance, while controlling for the geographic distance among samples. Neotropical migrants as a group were more 'sensitive' to landscape structure than either temperate migrants or permanent residents. Neotropical migrants tended to be more abundant in landscapes with a greater proportion of forest and wetland habitats, fewer edge habitats, large forest patches, and with forest habitats well dispersed throughout the scene. Permanent residents showed few correlations with landscape structure and temperate migrants were associated with habitat diversity and edge attributes rather than with the amount, size, and dispersion of forest habitats. The association between Neotropical migrant abundance and forest fragmentation differed among physiographic strata, suggesting that land-scape context affects observed relations between bird abundance and landscape structure. Finally, associations between landscape structure and temporal trends in Neotropical migrant abundance were negatively correlated with forest habitats. These results suggest that extrapolation of patterns observed in some landscapes is not likely to hold regionally, and that conservation policies must consider the variation in landscape

  8. Birds and bird habitats: guidelines for wind power projects

    International Nuclear Information System (INIS)

    2010-10-01

    Established in 2009, the Green Energy Act aims to increase the use of renewable energy sources including wind, water, solar and bioenergy in Ontario. The development of these resources is a major component of the province's plan, which aims to mitigate the contribution to climate change and to involve the Ontario's economy in the improvement of the quality of the environment. The Green Energy Act also considers as important the implementation of a coordinated provincial approval process, suggesting the integration of all Ministry requirements into a unique process during the evaluation of newly proposed renewable energy projects. The Ministry of the Environment's Renewable Energy Approval Regulation details the requirements for wind power projects involving significant natural features. Birds are an important part of Ontario's biodiversity and, according to the Ministry of Natural Resources, their habitats are considered as significant wildlife habitat (SWH). The Renewable Energy Approval Regulation and this guideline are meant to provide elements and guidance in order to protect bird SWH during the selection of a location of wind power facilities. . 27 refs., 1 tab., 2 figs.

  9. Infectious offspring: how birds acquire and transmit an avian polyomavirus in the wild.

    Directory of Open Access Journals (Sweden)

    Jaime Potti

    Full Text Available Detailed patterns of primary virus acquisition and subsequent dispersal in wild vertebrate populations are virtually absent. We show that nestlings of a songbird acquire polyomavirus infections from larval blowflies, common nest ectoparasites of cavity-nesting birds, while breeding adults acquire and renew the same viral infections via cloacal shedding from their offspring. Infections by these DNA viruses, known potential pathogens producing disease in some bird species, therefore follow an 'upwards vertical' route of an environmental nature mimicking horizontal transmission within families, as evidenced by patterns of viral infection in adults and young of experimental, cross-fostered offspring. This previously undescribed route of viral transmission from ectoparasites to offspring to parent hosts may be a common mechanism of virus dispersal in many taxa that display parental care.

  10. Bird sexing by Fourier transform infrared spectroscopy

    Science.gov (United States)

    Steiner, Gerald; Bartels, Thomas; Krautwald-Junghanns, Maria-Elisabeth; Koch, Edmund

    2010-02-01

    Birds are traditionally classified as male or female based on their anatomy and plumage color as judged by the human eye. Knowledge of a bird's gender is important for the veterinary practitioner, the owner and the breeder. The accurate gender determination is essential for proper pairing of birds, and knowing the gender of a bird will allow the veterinarian to rule in or out gender-specific diseases. Several biochemical methods of gender determination have been developed for avian species where otherwise the gender of the birds cannot be determined by their physical appearances or characteristics. In this contribution, we demonstrate that FT-IR spectroscopy is a suitable tool for a quick and objective determination of the bird's gender. The method is based on differences in chromosome size. Male birds have two Z chromosomes and female birds have a W-chromosome and a Z-chromosome. Each Z-chromosome has approx. 75.000.000 bps whereas the W-chromosome has approx. 260.00 bps. This difference can be detected by FT-IR spectroscopy. Spectra were recorded from germ cells obtained from the feather pulp of chicks as well as from the germinal disk of fertilized but non-bred eggs. Significant changes between cells of male and female birds occur in the region of phosphate vibrations around 1080 and 1120 cm-1.

  11. Ecological Sustainability of Birds in Boreal Forests

    Directory of Open Access Journals (Sweden)

    Gerald Niemi

    1998-12-01

    Full Text Available We review characteristics of birds in boreal forests in the context of their ecological sustainability under both natural and anthropogenic disturbances. We identify the underlying ecological factors associated with boreal bird populations and their variability, review the interactions between boreal bird populations and disturbance, and describe some tools on how boreal bird populations may be conserved in the future. The boreal system has historically been an area with extensive disturbance such as fire, insect outbreaks, and wind. In addition, the boreal system is vulnerable to global climate change as well as increasing pressure on forest and water resources. Current knowledge indicates that birds play an important role in boreal forests, and sustaining these populations affords many benefits to the health of boreal forests. Many issues must be approached with caution, including the lack of knowledge on our ability to mimic natural disturbance regimes with management, our lack of understanding on fragmentation due to logging activity, which is different from permanent conversion to other land uses such as agriculture or residential area, and our lack of knowledge on what controls variability in boreal bird populations or the linkage between bird population fluctuations and productivity. The essential role that birds can provide is to clarify important ecological concerns and variables that not only will help to sustain bird populations, but also will contribute to the long-term health of the boreal forest for all species, including humans.

  12. Lead and zinc intoxication in companion birds.

    Science.gov (United States)

    Puschner, Birgit; Poppenga, Robert H

    2009-01-01

    Although the toxicity of lead and zinc to birds is widely recognized by veterinarians and bird owners, these metals are frequently found in the environments of pet and aviary birds, and intoxications are common. Clinical signs exhibited by intoxicated birds are often nonspecific, which makes early diagnosis difficult. Fortunately, lead and zinc analyses of whole blood and serum or plasma, respectively, are readily available and inexpensive; elevated concentrations can confirm intoxication. Once diagnosed, intoxication can be effectively treated by (1) preventing further exposure, (2) administering chelating drugs, and (3) providing symptomatic and supportive care.

  13. Extensive dispersal of Roanoke logperch (Percina rex) inferred from genetic marker data

    Science.gov (United States)

    Roberts, James H.; Angermeier, Paul; Hallerman, Eric M.

    2016-01-01

    The dispersal ecology of most stream fishes is poorly characterised, complicating conservation efforts for these species. We used microsatellite DNA marker data to characterise dispersal patterns and effective population size (Ne) for a population of Roanoke logperchPercina rex, an endangered darter (Percidae). Juveniles and candidate parents were sampled for 2 years at sites throughout the Roanoke River watershed. Dispersal was inferred via genetic assignment tests (ATs), pedigree reconstruction (PR) and estimation of lifetime dispersal distance under a genetic isolation-by-distance model. Estimates of Ne varied from 105 to 1218 individuals, depending on the estimation method. Based on PR, polygamy was frequent in parents of both sexes, with individuals spawning with an average of 2.4 mates. The sample contained 61 half-sibling pairs, but only one parent–offspring pair and no full-sib pairs, which limited our ability to discriminate natal dispersal of juveniles from breeding dispersal of their parents between spawning events. Nonetheless, all methods indicated extensive dispersal. The AT indicated unrestricted dispersal among sites ≤15 km apart, while siblings inferred by the PR were captured an average of 14 km and up to 55 km apart. Model-based estimates of median lifetime dispersal distance (6–24 km, depending on assumptions) bracketed AT and PR estimates, indicating that widely dispersed individuals do, on average, contribute to gene flow. Extensive dispersal of P. rex suggests that darters and other small benthic stream fishes may be unexpectedly mobile. Monitoring and management activities for such populations should encompass entire watersheds to fully capture population dynamics.

  14. How to Throw a Bird?

    DEFF Research Database (Denmark)

    Zakaria, Anne Lassen; Bruun, Charlotte

    been left behind in global economic development, it is important to recognise that interventions, such as within tourism, cannot start on a tabula rasa. Hence, in this paper we argue that geographical locations are living systems where different stakeholders, formal and informal institutions......, environment with its wildlife, etc., all interact and influence interventions and outcomes. In metaphorical terms developing locations through tourism is like attempting to make a bird fly in a desired direction: One can never predict completely the direction in which it will fly. On the contrary throwing...

  15. O cuidado pré-natal em hospital universitário: uma avaliação de processo

    Directory of Open Access Journals (Sweden)

    Elizabeth Eriko Ishida Nagahama

    2006-01-01

    Full Text Available O objetivo do estudo foi avaliar o processo de atenção pré-natal referente à utilização do cuidado pré-natal do Programa Assistência Pré-natal às Gestantes de Baixo Risco do Hospital Universitário de Maringá, Paraná, Brasil. Compreendeu a seleção de critérios de qualidade que avaliaram a precocidade no ingresso e a adequação do número de consultas de pré-natal, mensuradas conforme o Programa de Humanização do Pré-natal e Nascimento do Ministério da Saúde e Índice de Adequação da Utilização do Cuidado Pré-natal. O estudo demonstrou que 44,5% gestantes iniciaram tardiamente o pré-natal, o que pode sugerir uma oferta limitada de vagas e a busca por melhor qualidade na atenção, demonstrada pela transferência espontânea de gestantes de outros serviços para o programa. As consultas de pré-natal foram garantidas, sendo o número médio ­ 9,8 consultas por gestante ­ superior aos parâmetros nacionais recomendados. Os indicadores utilizados e desenvolvidos para a avaliação de processo identificaram que o serviço ainda apresenta obstáculos ao acesso organizacional, necessitando, assim, da definição de estratégias que garantam essa diretriz fundamental do SUS.

  16. O cuidado pré-natal em hospital universitário: uma avaliação de processo

    Directory of Open Access Journals (Sweden)

    Nagahama Elizabeth Eriko Ishida

    2006-01-01

    Full Text Available O objetivo do estudo foi avaliar o processo de atenção pré-natal referente à utilização do cuidado pré-natal do Programa Assistência Pré-natal às Gestantes de Baixo Risco do Hospital Universitário de Maringá, Paraná, Brasil. Compreendeu a seleção de critérios de qualidade que avaliaram a precocidade no ingresso e a adequação do número de consultas de pré-natal, mensuradas conforme o Programa de Humanização do Pré-natal e Nascimento do Ministério da Saúde e Índice de Adequação da Utilização do Cuidado Pré-natal. O estudo demonstrou que 44,5% gestantes iniciaram tardiamente o pré-natal, o que pode sugerir uma oferta limitada de vagas e a busca por melhor qualidade na atenção, demonstrada pela transferência espontânea de gestantes de outros serviços para o programa. As consultas de pré-natal foram garantidas, sendo o número médio - 9,8 consultas por gestante - superior aos parâmetros nacionais recomendados. Os indicadores utilizados e desenvolvidos para a avaliação de processo identificaram que o serviço ainda apresenta obstáculos ao acesso organizacional, necessitando, assim, da definição de estratégias que garantam essa diretriz fundamental do SUS.

  17. Autonomy, natality and freedom: a liberal re-examination of Habermas in the enhancement debate.

    Science.gov (United States)

    Pugh, Jonathan

    2015-03-01

    Jurgen Habermas has argued that carrying out pre-natal germline enhancements would be inimical to the future child's autonomy. In this article, I suggest that many of the objections that have been made against Habermas' arguments by liberals in the enhancement debate misconstrue his claims. To explain why, I begin by explaining how Habermas' view of personal autonomy confers particular importance to the agent's embodiment and social environment. In view of this, I explain that it is possible to draw two arguments against germline enhancements from Habermas' thought. I call these arguments 'the argument from negative freedom' and 'the argument from natality'. Although I argue that many of the common liberal objections to Habermas are not applicable when his arguments are properly understood, I go on to suggest ways in which supporters of enhancement might appropriately respond to Habermas' arguments. © 2014 The Author. Bioethics published by John Wiley & Sons Ltd.

  18. Statistical processing of natality data for the Czech Republic before and after the Chernobyl accident

    International Nuclear Information System (INIS)

    Klepetkova, Hana; Thinova, Lenka

    2010-01-01

    All available data regarding natality in Czechoslovakia (or the Czech Republic) before and after the Chernobyl accident are summarized. Data from the databases of the Czech Statistical Office and of the State Office for Nuclear Safety were used to analyze natality and mortality of children in the Czech Republic and to evaluate the relationship between the level of contamination and the change in the sex ratio at time of birth that was observed in some areas in November of 1986. Although the change in the ratio of newborn boys-to-girls ratio was statistically significant, no direct relationship between that ratio and the level of contamination was found. Statistically significant changes in the sex ratio also occurred in Czechoslovakia (or in the Czech Republic) in the past, both before and after the accident. Furthermore, no statistically significant changes in the rate of stillbirths and multiple pregnancies were observed after the Chernobyl accident

  19. visões sobre o espaço urbano de Natal/RN

    Directory of Open Access Journals (Sweden)

    Edna Maria Furtado

    2007-01-01

    Full Text Available This study aimed at developing a Natal-city spatial "reading", capital of the state of Rio Grande do Norte, and its reconfiguration from the intensification of tourist activity, going through by geography, social sciences and economy, in a matrix approach that ignores the traditional limitations of science and recognizes the complexity around the world today. In light of this understanding, they have been analyzed the socio-economic connections that reform the landscape of Natal under the aegis of the new service-sector economy, led by tourism, in an intense process of city reconfiguration, focusing on three major areas and their irrigating arteries. These changes occur due to the public-private relationship __ via public policies __in the formation of new areas and the reform of old ones of the city, which contributed so that the tourist activity seize it, making it a socio-economic pattern that has obvious effects in its urban mapping.

  20. Enfermagem obstétrica no acompanhamento pré - natal

    Directory of Open Access Journals (Sweden)

    Lucia Helena Garcia Penna

    1999-09-01

    Full Text Available Consiste em um relato de experiência acerca de um projeto de pesquisa iniciado em agosto de 1997, envolvendo docentes do Departamento Materno-infantil da Faculdade de Enfermagem da UERJ e profissionais do Centro Municipal de Saúde do Rio de Janeiro da S.M.S./RJ. Tem por objetivo, descrever o processo de inserção da Consulta de Enfermagem de Pré-natal no conteúdo da graduação, bem como sua estruturação e implantação no referido Centro Municipal de Saúde. Esse trabalho propõe rever também, o modelo biomédico das consultas, a fim de proporcionar reflexões e rupturas de paradigmas, e com isso auxiliar no aprendizado e na ampliação do acompanhamento de pré-natal no Rio de Janeiro.

  1. Priority setting for bird conservation in Mexico: the role of the Important Bird Areas program

    Science.gov (United States)

    Ma. del Coro Arizmendi; Laura Marquez Valdelamar; Humberto Berlanga

    2005-01-01

    Many species in Mexico are threatened and in need of protection. At least seventy species are considered to be globally threatened, yet conservation actions have been scarce and not coordinated. In 1996 BirdLife International’s Important Bird Areas Program was initiated in Mexico to identify a network of the most important places in Mexico for birds, with the...

  2. 78 FR 11988 - Migratory Bird Subsistence Harvest in Alaska; Harvest Regulations for Migratory Birds in Alaska...

    Science.gov (United States)

    2013-02-21

    ..., accomplishments since the Migratory Bird Treaties with Canada and Mexico were amended, and a history, was... purposes during the spring and summer months. The Canada and Mexico migratory bird treaties were amended...-0066; FF09M21200-123-FXMB1231099BPP0L2] RIN 1018-AY70 Migratory Bird Subsistence Harvest in Alaska...

  3. 75 FR 18764 - Migratory Bird Subsistence Harvest in Alaska; Harvest Regulations for Migratory Birds in Alaska...

    Science.gov (United States)

    2010-04-13

    ... rulemaking, accomplishments since the Migratory Bird Treaties with Canada and Mexico were amended, and a... the spring and summer months. The Canada and Mexico migratory bird treaties were recently amended for... rural Alaska. The amendments to the Migratory Bird Treaties with Canada and Mexico recognize the...

  4. 75 FR 27143 - Migratory Bird Hunting; Proposed 2010-11 Migratory Game Bird Hunting Regulations (Preliminary...

    Science.gov (United States)

    2010-05-13

    ... Convention and the subsequent 1936 Mexico Convention for the Protection of Migratory Birds and Game Mammals... Part III Department of the Interior Fish and Wildlife Service 50 CFR Part 20 Migratory Bird Hunting; Proposed 2010-11 Migratory Game Bird Hunting Regulations (Preliminary) With Requests for Indian...

  5. 78 FR 65578 - Migratory Bird Permits; Depredation Order for Migratory Birds in California

    Science.gov (United States)

    2013-11-01

    ...-0037; FF09M21200-134-FXMB1231099BPP0] RIN 1018-AY65 Migratory Bird Permits; Depredation Order for Migratory Birds in California AGENCY: Fish and Wildlife Service, Interior. ACTION: Final rule. SUMMARY: We revise the regulations that allow control of depredating birds in California. We specify the counties in...

  6. 75 FR 3888 - Migratory Bird Subsistence Harvest in Alaska; Harvest Regulations for Migratory Birds in Alaska...

    Science.gov (United States)

    2010-01-25

    ...-0082; 91200-1231-9BPP-L2] RIN 1018-AW67 Migratory Bird Subsistence Harvest in Alaska; Harvest Regulations for Migratory Birds in Alaska During the 2010 Season AGENCY: Fish and Wildlife Service, Interior... Service, are reopening the public comment period on our proposed rule to establish migratory bird...

  7. A costal dispersion model

    International Nuclear Information System (INIS)

    Rahm, L.; Nyberg, L.; Gidhagen, L.

    1990-01-01

    A dispersion model to be used off costal waters has been developed. The model has been applied to describe the migration of radionuclides in the Baltic sea. A summary of the results is presented here. (K.A.E)

  8. Wave-equation dispersion inversion

    KAUST Repository

    Li, Jing; Feng, Zongcai; Schuster, Gerard T.

    2016-01-01

    We present the theory for wave-equation inversion of dispersion curves, where the misfit function is the sum of the squared differences between the wavenumbers along the predicted and observed dispersion curves. The dispersion curves are obtained

  9. A Profile of KwaZulu-Natal: Demographics, Poverty, Inequality and Unemployment

    OpenAIRE

    Pauw, Kalie

    2005-01-01

    This paper forms part of a series of papers that present profiles of South Africa's provinces, with a specific focus on key demographic statistics, poverty and inequality estimates, and estimates of unemployment. In this volume comparative statistics are presented for agricultural and non-agricultural households, as well as households from different racial groups, locations (metropolitan, urban and rural areas) and district municipalities of KwaZulu-Natal. Most of the data presented are drawn...

  10. Muslim women’s identities in South Africa: A Zanzibari perspective in KwaZulu-Natal.

    OpenAIRE

    Vahed, Goolam

    2014-01-01

    This article examines how Zanzibari women in KwaZulu-Natal are negotiating their identities within the context of local and global realities. In South Africa, while the post-apartheid period gave birth to non-racial democracy, South Africa is haunted by high unemployment, widespread poverty and poor service delivery. Globally, this period has witnessed increased conflict since the 9/11 attacks on the Twin Towers in New York and the subsequent War on Terror which has led some...

  11. Efficacy of collateral types used by financial intermediaries in KwaZulu-Natal

    OpenAIRE

    Kuhn, M.E.; Darroch, Mark A.G.; Ortmann, Gerald F.

    1997-01-01

    Collateral is an important incentive device used by lenders to encourage loan repayment. However, collateral must have secure and transferable title, it must be marketable, have low lender liquidation costs and lenders must be able to attach the collateral. Study results for rural and micro-enterprise finance institutions in KwaZulu-Natal showed that assets such as vehicles and equipment were not effective as collateral due to high costs in attaching the asset. Cessions on crops were often co...

  12. Biodiversity of frog haemoparasites from sub-tropical northern KwaZulu-Natal, South Africa

    OpenAIRE

    Edward C. Netherlands; Courtney A. Cook; Donnavan J.D. Kruger; Louis H. du Preez; Nico J. Smit

    2015-01-01

    Since South Africa boasts a high biodiversity of frog species, a multispecies haemoparasite survey was conducted by screening the blood from 29 species and 436 individual frogs. Frogs were collected at three localities in sub-tropical KwaZulu-Natal, a hotspot for frog diversity. Twenty per cent of the frogs were infected with at least one of five groups of parasites recorded. Intraerythrocytic parasites comprising Hepatozoon, Dactylosoma, and viral or bacterial organisms, as well as extracell...

  13. Challenges in the prenatal and post-natal diagnosis of mediastinal cystic hygroma: a case report

    Directory of Open Access Journals (Sweden)

    Nazir Sarfraz

    2008-08-01

    Full Text Available Abstract Introduction Cystic hygroma is a benign congenital neoplasm that mostly presents as a soft-tissue mass in the posterior triangle of the neck. Pure mediastinal lesions are uncommon; the vast majority are asymptomatic and are an incidental finding in adulthood. The diagnosis is often made intra- or postoperatively. Prenatal identification is exceptional and post-natal diagnosis also proves challenging. Case presentation We report one such case that was mistaken for other entities in both the prenatal and immediate post-natal period. Initial and follow-up antenatal ultrasound scans demonstrated a multicystic lesion in the left chest, and the mother was counselled about the possibility of her baby having a congenital diaphragmatic hernia. Initial post-natal chest radiographs were reported as normal. An echocardiogram and thoracic computed tomography scan confirmed a complex multiloculated cystic mediastinal mass. The working diagnoses were of a mediastinal teratoma or congenital cystic adenomatous malformation. At operation, the lesion was compressed by the left lung and was found to be close to the left phrenic nerve, which was carefully identified and preserved. After excision, histopathological examination of the mass confirmed the diagnosis of cystic hygroma. Postoperative dyspnoea was observed secondary to paradoxical movement of the left hemidiaphragm and probable left phrenic neuropraxia. This settled conservatively with excellent recovery. Conclusion Despite the fact that isolated intrathoracic cystic hygroma is a rare entity, it needs to be considered in the differential diagnosis of foetal and neonatal mediastinal masses, particularly for juxtadiaphragmatic lesions. The phrenic nerve is not identifiable on prenatal ultrasound imaging, and it is therefore understandable that a mass close to the diaphragm may be mistaken for a congenital diaphragmatic hernia because of the location, morphology and potential phrenic nerve compression

  14. EMERGÊNCIA DOS "CONDOMÍNIOS-CLUBE" NA ZONA SUL DE NATAL/RN, BRASIL

    Directory of Open Access Journals (Sweden)

    Felipe Fernandes de Araújo

    2012-01-01

    Full Text Available Este documento tiene como objetivo discutir el surgimiento de una nueva tipología residencial que se ha extendido en el sur de Natal / RN, los condominios llamado Club. Su principal característica es la apelación a los artículos de ocio más diversos, que son utilizados por los empresarios urbanos como una forma de crear un nuevo estilo de vida y un nuevo producto que se vende. La base teórica de este trabajo se basa en el enfoque heterodoxo de la coordinación espacial realizada por Pedro Abramo. Esta perspectiva considera el espacio urbano como un conjunto de inventario de viviendas que son ofrecidas por los empresarios urbanos. En general, el orden urbano y el ambiente residencial es incierto, porque sufren cambios derivados de la aparición de las innovaciones de espacio causadas por empresarios urbanos en busca de beneficios extraordinarios. En el caso de la zona sur de Natal, la construcción de carreteras principales que conectan esta zona de la ciudad al vecino municipio de Parnamirim, que ha sido el blanco de la abundancia del mercado inmobiliario de Natal. El ciclo de vida de los inventarios residenciales de la Zona Sur de Natal ha cambiado con el tiempo, desde el principio de la vivienda en grandes alojamientos para la producción de proyectos verticais. En la actualidad, un fenómeno nuevo que se plantea es la propagación de una nueva clasificación, los condominios club. Al ser un caso reciente en que los proyectos se encuentran todavía en fase de lanzamiento o de la construcción, el estudio se llevará a cabo mediante el análisis de marketing utilizadas por los empresarios urbanos para atraer a los consumidores a través de panfletos y folletos.

  15. Reactimeter dispersion equation

    OpenAIRE

    A.G. Yuferov

    2016-01-01

    The aim of this work is to derive and analyze a reactimeter metrological model in the form of the dispersion equation which connects reactimeter input/output signal dispersions with superimposed random noise at the inlet. It is proposed to standardize the reactimeter equation form, presenting the main reactimeter computing unit by a convolution equation. Hence, the reactimeter metrological characteristics are completely determined by this unit hardware function which represents a transient re...

  16. The search for the youngest granites in the southern part of the Natal Metamorphic Province

    International Nuclear Information System (INIS)

    Thomas, R.J.; Eglington, B.M.

    1990-01-01

    It is clear that the Belmont Pluton and the dykes are geochemically, isotopically and therefore, genetically distinct. The Belmont pluton is probably related to the garnet leucogranite phase of the Margate Complex. It is suggested that the dykes (∼ 965 Ma) are younger than the Belmont pluton (∼1055 Ma). The relatively low initial 87 Sr/ 86 Sr are typical of the granites intruded at ∼1000 Ma. The age of the dykes is comparable with the 951 ± 16 Ma (R o =.70320 ± 13) given for the Sezela pluton. The high R o (∼0.715) of the dykes is similar to other, minor granite sheets from southern Natal, and is compatible with an origin by late-stage melting of pre-existing radiogenic material. Both the dykes and the Sezela pluton are unequivocally younger than the D 3 deformation, whereas the young dates from the Oribi Gorge Suite are controversial. Thus, although it is possible that some of the minor, intrusive granitic sheets could yet be shown to be of Pan-African age, it is evident that no significant Pan-African magmatism or thermal overprinting has affected the Natal sector of the Namaqua-Natal-Maudheim belt. 1 fig., 7 refs

  17. Conceptions of Contraceptive Use in Rural KwaZulu-Natal, South Africa: Lessons for Programming

    Science.gov (United States)

    Ndinda, Catherine; Ndhlovu, Tidings; Khalema, Nene Ernest

    2017-01-01

    Community family planning programmes in South Africa arose from the controversial apartheid history of controlling the African population while encouraging the growth of European migrant population. Post-apartheid population policies shifted away from population control to aligning policies to the global agenda that placed emphasis on the link between population and development. The focus on population and development polices in post-apartheid South Africa is on social equality, justice and peace rather than controlling sections of the population. Given the shift, this paper interrogates the conceptions of contraceptive use among rural communities in KwaZulu-Natal. Our primary objective is to understand the dynamics surrounding access to and use of family planning services in peri-urban and rural areas of KwaZulu-Natal. Using focus group data, the findings of the study suggest that different social categories interact with the family planning programmes differently. How teenagers and married women perceive the value of family planning differs. Gender differences regarding the use of condoms are also evident. The paper attempts to grapple with the non-use of condoms despite the knowledge that these prevent pregnancy and provide protection from sexually-transmitted diseases. The contribution of this paper lies in its identification of socio-cultural factors and the political economy underlying the different attitudes towards contraceptive use in rural KwaZulu-Natal. PMID:28350334

  18. UNDERSTANDING COMPACT OBJECT FORMATION AND NATAL KICKS. II. THE CASE OF XTE J1118 + 480

    International Nuclear Information System (INIS)

    Fragos, T.; Willems, B.; Kalogera, V.; Ivanova, N.; Rockefeller, G.; Fryer, C. L.; Young, P. A.

    2009-01-01

    In recent years, an increasing number of proper motions have been measured for Galactic X-ray binaries. When supplemented with accurate determinations of the component masses, orbital period, and donor effective temperature, these kinematical constraints harbor a wealth of information on the system's past evolution. Here, we consider all this available information to reconstruct the full evolutionary history of the black hole X-ray binary XTE J1118 + 480, assuming that the system originated in the Galactic disk and the donor has solar metallicity. This analysis accounts for four evolutionary phases: mass transfer through the ongoing X-ray phase, tidal evolution before the onset of Roche lobe overflow, motion through the Galactic potential after the formation of the black hole, and binary orbital dynamics due to explosive mass loss and possibly a black hole natal kick at the time of core collapse. We find that right after black hole formation, the system consists of a ≅6.0-10.0 M sun black hole and a ≅1.0-1.6 M sun main-sequence star. We also find that that an asymmetric natal kick is not only plausible but required for the formation of this system, and derive a lower and upper limit on the black hole natal kick velocity magnitude of 80 km s -1 and 310 km s -1 , respectively.

  19. Conceptions of Contraceptive Use in Rural KwaZulu-Natal, South Africa: Lessons for Programming.

    Science.gov (United States)

    Ndinda, Catherine; Ndhlovu, Tidings; Khalema, Nene Ernest

    2017-03-28

    Community family planning programmes in South Africa arose from the controversial apartheid history of controlling the African population while encouraging the growth of European migrant population. Post-apartheid population policies shifted away from population control to aligning policies to the global agenda that placed emphasis on the link between population and development. The focus on population and development polices in post-apartheid South Africa is on social equality, justice and peace rather than controlling sections of the population. Given the shift, this paper interrogates the conceptions of contraceptive use among rural communities in KwaZulu-Natal. Our primary objective is to understand the dynamics surrounding access to and use of family planning services in peri-urban and rural areas of KwaZulu-Natal. Using focus group data, the findings of the study suggest that different social categories interact with the family planning programmes differently. How teenagers and married women perceive the value of family planning differs. Gender differences regarding the use of condoms are also evident. The paper attempts to grapple with the non-use of condoms despite the knowledge that these prevent pregnancy and provide protection from sexually-transmitted diseases. The contribution of this paper lies in its identification of socio-cultural factors and the political economy underlying the different attitudes towards contraceptive use in rural KwaZulu-Natal.

  20. Substance use and duration of untreated psychosis in KwaZulu-Natal, South Africa

    Directory of Open Access Journals (Sweden)

    Glen P. Davis

    2016-05-01

    Full Text Available Background: Substance use and psychiatric disorders cause significant burden of disease in low- and middle-income countries. Co-morbid psychopathology and longer duration of untreated psychosis (DUP can negatively affect treatment outcomes. Objectives: The study assessed substance use amongst adults with severe mental illness receiving services at a regional psychiatric hospital in KwaZulu-Natal (South Africa. We describe the prevalence and correlates of lifetime substance use and examine the association between substance use and DUP. Methods: A cross-sectional survey recruited adults diagnosed with severe mental illness and assessed lifetime and past 3-month substance use using the World Health Organization Alcohol, Smoking and Substance Involvement Screening Test. Regression analyses were conducted to determine associations between lifetime substance use (other than alcohol and tobacco and DUP as measured by the World Health Organization Encounter Form. Results: Amongst 87 participants, alcohol (81.6%, tobacco (75.6% and cannabis (49.4% were the most common substances reported for lifetime use. Risk of health-related problems (health, social, financial, legal and relationship of cannabis use was associated with younger age, single marital status and lower education. Adjusted regression analyses indicated that use of amphetamines and methaqualone is associated with longer DUP. Conclusions: Substance use is prevalent amongst psychiatric patients in KwaZulu-Natal and may contribute to longer DUP. Mental health services in this region should address co-morbid substance use and psychiatric disorders. Keywords: Substance Use; Psychosis; KwaZulu-Natal

  1. Fickian dispersion is anomalous

    Science.gov (United States)

    Cushman, John H.; O'Malley, Dan

    2015-12-01

    The thesis put forward here is that the occurrence of Fickian dispersion in geophysical settings is a rare event and consequently should be labeled as anomalous. What people classically call anomalous is really the norm. In a Lagrangian setting, a process with mean square displacement which is proportional to time is generally labeled as Fickian dispersion. With a number of counter examples we show why this definition is fraught with difficulty. In a related discussion, we show an infinite second moment does not necessarily imply the process is super dispersive. By employing a rigorous mathematical definition of Fickian dispersion we illustrate why it is so hard to find a Fickian process. We go on to employ a number of renormalization group approaches to classify non-Fickian dispersive behavior. Scaling laws for the probability density function for a dispersive process, the distribution for the first passage times, the mean first passage time, and the finite-size Lyapunov exponent are presented for fixed points of both deterministic and stochastic renormalization group operators. The fixed points of the renormalization group operators are p-self-similar processes. A generalized renormalization group operator is introduced whose fixed points form a set of generalized self-similar processes. Power-law clocks are introduced to examine multi-scaling behavior. Several examples of these ideas are presented and discussed.

  2. Eye lesions in pet birds.

    Science.gov (United States)

    Tsai, S S; Park, J H; Hirai, K; Itakura, C

    1993-03-01

    Amongst eye lesions in birds that died in quarantine, cataracts were the most common disorders (37/241, 15.4%), being prevalent in the annular pads of cockatiels (Nymphicus hollandicus), Amazon parrots (Amazona aestiva aestiva) and budgerigars (Melopsittacus undulatus). The incidence in male birds was more than twice that in females. Deposition of crystals, mostly in the cornea, was the second most frequent lesion (21/293, 8.7%), mainly found in cockatiels, parakeets (Psittacula krameri manillensis), Amazon parrots (Amazona aestiva aestiva), budgerigars and finches (Poephila gouldiae gouldiae). These corneal crystals were negative to PAS and Kossa's stains. Six parakeets (Psittacula krameri manillensis) had calcium salts deposited in the inner plexiform layer of the retina and occasionally in the iris and ciliary body. Neither inflammation nor neo-vascularization was observed when cataracts, corneal crystalline deposition, and retinal and ciliary calcification were present. Intranuclear inclusion bodies typical for papovavirus infection were found in the eyelids of six budgerigars (2.5%). Similar inclusions were simultaneously found in the pars ciliaris retinae (4, 1.7%), inner plexiform of retina (1, 0.4%) and anterior epithelium of the cornea (1, 0.4%). Other lesions such as candidial endophthalmitis, conjunctival cryptosporidiosis, corneal dystrophy, keratitis, corneal perforation and iridocyclitis, were occasional findings.

  3. Do Birds Experience Sensory Pleasure?

    Directory of Open Access Journals (Sweden)

    Michel Cabanac

    2009-01-01

    Full Text Available To answer the question of whether sensory pleasure exists in birds, I trained an African-gray parrot (Psittacus erythacus named Aristote to speak. Stage 1 of the study consisted in gaining Aristote's affection. In Stage 2 Aristote was taught to speak, following Irene Pepperberg's triangular method: another person and I would talk together and look at Aristote only when it used understandable French words. Thus Aristote learned to say a few words for obtaining toys or getting my attention; e.g. “donne bouchon” (give cork or “donne gratte” (give scratch/tickle, with the appropriate reward. In Stage 3, the word bon (good was added to the short list of words used by Aristote. I said “bon” when giving Aristote the stimuli it requested and which would, presumably, be pleasurable; e.g. gratte bon. Aristote started to use short sentences such as “yaourt bon” (good yogurt. Eventually, Aristote transferred the word bon to new stimuli such as raisin (grape, an association I myself had never made. Such a use of vocabulary, and moreover its transfer, likely shows that this bird experienced sensory pleasure.

  4. Dermal extracellular lipid in birds.

    Science.gov (United States)

    Stromberg, M W; Hinsman, E J; Hullinger, R L

    1990-01-01

    A light and electron microscopic study of the skin of domestic chickens, seagulls, and antarctic penguins revealed abundant extracellular dermal lipid and intracellular epidermal lipid. Dermal lipid appeared ultrastructurally as extracellular droplets varying from less than 1 micron to more than 25 microns in diameter. The droplets were often irregularly contoured, sometimes round, and of relatively low electron density. Processes of fibrocytes were often seen in contact with extracellular lipid droplets. Sometimes a portion of such a droplet was missing, and this missing part appeared to have been "digested away" by the cell process. In places where cells or cell processes are in contact with fact droplets, there are sometimes extracellular membranous whorls or fragments which have been associated with the presence of fatty acids. Occasionally (in the comb) free fat particles were seen in intimate contact with extravasated erythrocytes. Fat droplets were seen in the lumen of small dermal blood and lymph vessels. We suggest that the dermal extracellular lipid originates in the adipocyte layer and following hydrolysis the free fatty acids diffuse into the epidermis. Here they become the raw material for forming the abundant neutral lipid contained in many of the epidermal cells of both birds and dolphins. The heretofore unreported presence and apparently normal utilization of abundant extracellular lipid in birds, as well as the presence of relatively large droplets of neutral lipid in dermal vessels, pose questions which require a thorough reappraisal of present concepts of the ways in which fat is distributed and utilized in the body.

  5. Local equilibrium in bird flocks

    Science.gov (United States)

    Mora, Thierry; Walczak, Aleksandra M.; Del Castello, Lorenzo; Ginelli, Francesco; Melillo, Stefania; Parisi, Leonardo; Viale, Massimiliano; Cavagna, Andrea; Giardina, Irene

    2016-12-01

    The correlated motion of flocks is an example of global order emerging from local interactions. An essential difference with respect to analogous ferromagnetic systems is that flocks are active: animals move relative to each other, dynamically rearranging their interaction network. This non-equilibrium characteristic has been studied theoretically, but its impact on actual animal groups remains to be fully explored experimentally. Here, we introduce a novel dynamical inference technique, based on the principle of maximum entropy, which accommodates network rearrangements and overcomes the problem of slow experimental sampling rates. We use this method to infer the strength and range of alignment forces from data of starling flocks. We find that local bird alignment occurs on a much faster timescale than neighbour rearrangement. Accordingly, equilibrium inference, which assumes a fixed interaction network, gives results consistent with dynamical inference. We conclude that bird orientations are in a state of local quasi-equilibrium over the interaction length scale, providing firm ground for the applicability of statistical physics in certain active systems.

  6. Lead Poisoning in Wild Birds

    Science.gov (United States)

    Lahner, Lesanna L.; Franson, J. Christian

    2009-01-01

    Lead in its various forms has been used for thousands of years, originally in cooking utensils and glazes and more recently in many industrial and commercial applications. However, lead is a potent, potentially deadly toxin that damages many organs in the body and can affect all animals, including humans. By the mid 1990s, lead had been removed from many products in the United States, such as paint and fuel, but it is still commonly used in ammunition for hunting upland game birds, small mammals, and large game animals, as well as in fishing tackle. Wild birds, such as mourning doves, bald eagles, California condors, and loons, can die from the ingestion of one lead shot, bullet fragment, or sinker. According to a recent study on loon mortality, nearly half of adult loons found sick or dead during the breeding season in New England were diagnosed with confirmed or suspected lead poisoning from ingestion of lead fishing weights. Recent regulations in some states have restricted the use of lead ammunition on certain upland game hunting areas, as well as lead fishing tackle in areas frequented by common loons and trumpeter swans. A variety of alternatives to lead are available for use in hunting, shooting sports, and fishing activities.

  7. Hermit Thrush is the First Observed Dispersal Agent for Pondberry (Lindera melissifolia)

    Science.gov (United States)

    Carl G. Smith; Paul B. Hamel; Margaret S. Devall; Natan M. Schiff

    2004-01-01

    We investigated dispersal opportunities for the endangered pondberry, Lindera melissifolia (Lauraceae). In 199 hours of observation at 5 fruiting colonies in the Delta National Forest, Sharkey County, Mississippi, we recorded 82 bird species in the vicinity of a colony. Of these, 12 were observed on pondberry plants, and two consumed ripe pondberry...

  8. No evidence that migratory geese disperse avian influenza viruses from breeding to wintering ground

    NARCIS (Netherlands)

    Yin, Shenglai; Kleijn, David; Müskens, Gerard J.D.M.; Fouchier, Ron A.M.; Verhagen, Josanne H.; Glazov, Petr M.; Si, Yali; Prins, Herbert H.T.; Boer, de Fred

    2017-01-01

    Low pathogenic avian influenza virus can mutate to a highly pathogenic strain that causes severe clinical signs in birds and humans. Migratory waterfowl, especially ducks, are considered the main hosts of low pathogenic avian influenza virus, but the role of geese in dispersing the virus over

  9. No evidence that migratory geese disperse avian influenza viruses from breeding to wintering ground

    NARCIS (Netherlands)

    Yin, S. (Shenglai); D. Kleijn (David); Müskens, G.J.D.M. (Gerard J. D. M.); R.A.M. Fouchier (Ron); J.H. Verhagen (Josanne); Glazov, P.M. (Petr M.); Si, Y. (Yali); Prins, H.H.T. (Herbert H. T.); De Boer, W.F. (Willem Frederik)

    2017-01-01

    textabstractLow pathogenic avian influenza virus can mutate to a highly pathogenic strain that causes severe clinical signs in birds and humans. Migratory waterfowl, especially ducks, are considered the main hosts of low pathogenic avian influenza virus, but the role of geese in dispersing the virus

  10. Effects of land use on bird populations and pest control services on coffee farms

    Science.gov (United States)

    Railsback, Steven F.; Johnson, Matthew D.

    2014-01-01

    Global increases in both agriculture and biodiversity awareness raise a key question: Should cropland and biodiversity habitat be separated, or integrated in mixed land uses? Ecosystem services by wildlife make this question more complex. For example, birds benefit agriculture by preying on pest insects, but other habitat is needed to maintain the birds. Resulting land use questions include what areas and arrangements of habitat support sufficient birds to control pests, whether this pest control offsets the reduced cropland, and the comparative benefits of “land sharing” (i.e., mixed cropland and habitat) vs. “land sparing” (i.e., separate areas of intensive agriculture and habitat). Such questions are difficult to answer using field studies alone, so we use a simulation model of Jamaican coffee farms, where songbirds suppress the coffee berry borer (CBB). Simulated birds select habitat and prey in five habitat types: intact forest, trees (including forest fragments), shade coffee, sun coffee, and unsuitable habitat. The trees habitat type appears to be especially important, providing efficient foraging and roosting sites near coffee plots. Small areas of trees (but not forest alone) could support a sufficient number of birds to suppress CBB in sun coffee; the degree to which trees are dispersed within coffee had little effect. In simulations without trees, shade coffee supported sufficient birds to offset its lower yield. High areas of both trees and shade coffee reduced pest control because CBB was less often profitable prey. Because of the pest control service provided by birds, land sharing was predicted to be more beneficial than land sparing in this system. PMID:24711377

  11. Effects of land use on bird populations and pest control services on coffee farms.

    Science.gov (United States)

    Railsback, Steven F; Johnson, Matthew D

    2014-04-22

    Global increases in both agriculture and biodiversity awareness raise a key question: Should cropland and biodiversity habitat be separated, or integrated in mixed land uses? Ecosystem services by wildlife make this question more complex. For example, birds benefit agriculture by preying on pest insects, but other habitat is needed to maintain the birds. Resulting land use questions include what areas and arrangements of habitat support sufficient birds to control pests, whether this pest control offsets the reduced cropland, and the comparative benefits of "land sharing" (i.e., mixed cropland and habitat) vs. "land sparing" (i.e., separate areas of intensive agriculture and habitat). Such questions are difficult to answer using field studies alone, so we use a simulation model of Jamaican coffee farms, where songbirds suppress the coffee berry borer (CBB). Simulated birds select habitat and prey in five habitat types: intact forest, trees (including forest fragments), shade coffee, sun coffee, and unsuitable habitat. The trees habitat type appears to be especially important, providing efficient foraging and roosting sites near coffee plots. Small areas of trees (but not forest alone) could support a sufficient number of birds to suppress CBB in sun coffee; the degree to which trees are dispersed within coffee had little effect. In simulations without trees, shade coffee supported sufficient birds to offset its lower yield. High areas of both trees and shade coffee reduced pest control because CBB was less often profitable prey. Because of the pest control service provided by birds, land sharing was predicted to be more beneficial than land sparing in this system.

  12. The Netherlands Bird Avoidance Model, Final Report

    NARCIS (Netherlands)

    Shamoun-Baranes, J.; Bouten, W.; Sierdsema, H.; van Belle, J.; van Gasteren, J.R.; van Loon, E.E.

    2006-01-01

    The NL-BAM was developed as a web-based decision support tool to be used by the bird hazard avoidance experts in the ecology unit of the Royal Netherlands Air Force. The NL-BAM will be used together with the ROBIN 4 radar system to provide BirdTAMS, for real time warnings and flight planning and to

  13. Cryptococcosis outbreak in psittacine birds in Brazil.

    Science.gov (United States)

    Raso, T F; Werther, K; Miranda, E T; Mendes-Giannini, M J S

    2004-08-01

    An outbreak of cryptococcosis occurred in a breeding aviary in São Paulo, Brazil. Seven psittacine birds (of species Charmosyna papou, Lorius lory, Trichoglossus goldiei, Psittacula krameri and Psittacus erithacus) died of disseminated cryptococcosis. Incoordination, progressive paralysis and difficulty in flying were seen in five birds, whereas superficial lesions coincident with respiratory alterations were seen in two birds. Encapsulated yeasts suggestive of Cryptococcus sp. were seen in faecal smears stained with India ink in two cases. Histological examination of the birds showed cryptococcal cells in various tissues, including the beak, choana, sinus, lungs, air sacs, heart, liver, spleen, kidneys, intestines and central nervous system. High titres of cryptococcal antigen were observed in the serum of an affected bird. In this case, titres increased during treatment and the bird eventually died. Yeasts were isolated from the nasal mass, faeces and liver of one bird. Cryptococcus neoformans var. gattii serovar B was identified based on biochemical, physiological and serological tests. These strains were resistant (minimum inhibitory concentration 64 microg/ml) to fluconazole. This is the first report of C. neoformans var. gattii occurring in psittacine birds in Brazil.

  14. Bird observations in Severnaya Zemlya, Siberia

    NARCIS (Netherlands)

    de ext. Korte, J.; Volkov, A.E; Gavrilo, M.V

    Fieldwork in different parts of Severnaya Zemlya in 1985, 1991, 1992 and 1993 and aerial surveys in 1994 revealed a limited bird fauna with a total of 17 breeding species. The most numerous breeding birds are cliff-nesting seabirds, comprising little auk (Alle alle), 10 000-80 000 pairs; kittiwake

  15. Estimating the Impact of Bird Strikes

    NARCIS (Netherlands)

    Metz, I.C.; Muhlhausen, Thorsten; Ellerbroek, J.; Hoekstra, J.M.

    2018-01-01

    Bird strikes have the potential to cause severe damage to aircraft. Therefore, measures to reduce the risk of bird strikes are performed at airports. However, this risk is not limited to the airport but is increased in the arrival and departure corridors as well. Consequently, a significant amount

  16. Pheromones in birds: myth or reality?

    NARCIS (Netherlands)

    Caro, S.P.; Balthazart, J.

    2010-01-01

    Birds are anosmic or at best microsmatic… This misbelief persisted until very recently and has strongly influenced the outcome of communication studies in birds, with olfaction remaining neglected as compared to acoustic and visual channels. However, there is now clear empirical evidence showing

  17. Ability of Slovakian Pupils to Identify Birds

    Science.gov (United States)

    Prokop, Pavol; Rodak, Rastislav

    2009-01-01

    A pupil's ability to identify common organisms is necessary for acquiring further knowledge of biology. We investigated how pupils were able to identify 25 bird species following their song, growth habits, or both features presented simultaneously. Just about 19% of birds were successfully identified by song, about 39% by growth habit, and 45% of…

  18. The Popularity of Birding is Still Growing

    Science.gov (United States)

    H. Ken Cordell; Nancy G. Herbert

    2002-01-01

    What are the "field marks" of the entry-level birder of the past few years? She is probably between 40 and 59 years old and is white. She puts in about 10 birding days or fewer per year, trying to squeeze birding into a busy life, although she also finds herself engaged in related activities: walking for pleasure, attending family outdoor gatherings...

  19. PREVALENCE OF BIRD LOUSE, MENACANTHUS CORNUTUS ...

    African Journals Online (AJOL)

    ADMIN

    2014-06-01

    Jun 1, 2014 ... Department of Biological Sciences, Bayero University P.M.B 3011 Kano, Nigeria ... Birds were randomly picked and viewed under day light with the aid of hand lens and dissecting forceps to facilitate ... another when birds are kept in close contact (Price et al., 2003). They are ... MATERIALS AND METHODS.

  20. Smelling out predators is innate in birds

    NARCIS (Netherlands)

    Amo, L.; Visser, M.E.; Van Oers, K.

    2011-01-01

    The role of olfaction for predation risk assessment remains barely explored in birds, although predator chemical cues could be useful in predator detection under low visibility conditions for many bird species. We examine whether Great Tits Parus major are able to use the odour of mustelids to

  1. Current perspectives on the evolution of birds

    NARCIS (Netherlands)

    Ericson, P.G.P.

    2008-01-01

    The paper summarizes the current understanding of the evolution and diversification of birds. New insights into this field have mainly come from two fundamentally different, but complementary sources of information: the many newly discovered Mesozoic bird fossils and the wealth of genetic analyses

  2. [Hemoparasites in wild birds in Madagascar].

    Science.gov (United States)

    Raharimanga, V; Soula, F; Raherilalao, M J; Goodman, S M; Sadonès, H; Tall, A; Randrianarivelojosia, M; Raharimalala, L; Duchemin, J B; Ariey, F; Robert, V

    2002-01-01

    This study aims to evaluate the prevalence and density of haemoparasites in native Malagasy birds. Among the 387 birds, belonging to 43 species sampled at six localities in different bio-climatic zones of the island, 139 (35.9%) showed at least 1 hemoparasite with, by order of frequency, Plasmodium and/or Haemoproteus (19.9%), microfilariae (13.7% of 387 birds), Leucocytozoon (11.1%) and Trypanosoma (1.0%). An analysis to further elucidate these observations took into account the interaction of different environmental variables (altitude, season, site of collection) or aspects of the birds (age, weight, sex). There is evidence that some parasites preferentially infect some bird species or families. The largest male birds harboured the highest prevalences and densities of haemoparasite, regardless of species. These findings extend knowledge of bird/blood parasite relationships of Malagasy birds and provide interesting insights, especially concerning the pathogenicity of this type of parasitism and the parasite transmission by insect vectors.

  3. Sífilis Congênita como Indicador de Assistência Pré-natal

    Directory of Open Access Journals (Sweden)

    De Lorenzi Dino Roberto Soares

    2001-01-01

    Full Text Available Objetivos: estudar a prevalência de sífilis congênita (SC em um hospital universitário da região sul do Brasil, destacando seu papel como indicador de qualidade da assistência pré-natal. Método: estudo descritivo dos casos de SC ocorridos no HG-UCS, no período de 1 de junho de 2000 a 31 de maio de 2001, com base nos critérios diagnósticos propostos pelo Centers for Disease Control and Prevention (CDC, 1998. Resultados: a prevalência de sífilis congênita observada foi de 1,5% (27 casos em 1739 nascimentos. O coeficiente de SC encontrado foi de 15,5 casos por 1000 nascidos vivos. Das 23 gestantes (85,2% que relataram acompanhamento pré-natal prévio, em apenas 16 (69,6% casos o diagnóstico de sífilis materna foi realizado antes do parto. Somente 4 gestantes (17,4% foram adequadamente tratadas durante o pré-natal, de modo a prevenir a transmissão vertical da doença. Em 8 casos (29,6% constatou-se a associação da sífilis materna com outras doenças sexualmente transmissíveis. O coeficiente de mortalidade perinatal por SC foi de 1,15 por 1000 nascidos vivos (2 mortes perinatais. Conclusões: os autores reafirmam a importância da SC como indicador de saúde perinatal, visto ser uma doença totalmente passível de prevenção durante o pré-natal. A elevada prevalência de SC observada permite questionar a qualidade da atenção pré-natal disponível à população estudada.

  4. Neospora caninum in birds: A review.

    Science.gov (United States)

    de Barros, Luiz Daniel; Miura, Ana Carolina; Minutti, Ana Flávia; Vidotto, Odilon; Garcia, João Luis

    2018-08-01

    Neospora caninum is an obligate intracellular protozoan parasite that infects domestic and wild animals. Canids are considered to be definitive hosts since they may shed oocysts into the environment through their feces. The disease is recognized as one of the major causes of bovine abortion worldwide, leading to important economic losses in the dairy and beef cattle industries. Previous studies have reported N. caninum infection in different species of birds; infection in birds has been associated with increased seroprevalence and reproductive problems in dairy cattle. Although the role of birds in the epidemiological cycle of neosporosis is unknown, birds are exposed to infection because they feed on the ground and could thus contribute to parasite dissemination. This review is focused on the current state of knowledge of neosporosis in birds. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Occurrence of keratinophilic fungi on Indian birds.

    Science.gov (United States)

    Dixit, A K; Kushwaha, R K

    1991-01-01

    Keratinophilic fungi were isolated from feathers of most common Indian birds, viz. domestic chicken (Gallus domesticus), domestic pigeon (Columba livia), house sparrow (Passer domesticus), house crow (Corvus splendens), duck (Anas sp.), rose-ringed parakeet (Psittacula krameri). Out of 87 birds, 58 yielded 4 keratinophilic fungal genera representing 13 fungal species and one sterile mycelium. The isolated fungi were cultured on Sabouraud's dextrose agar at 28 +/- 2 degrees C. Chrysosporium species were isolated on most of the birds. Chrysosporium lucknowense and Chrysosporium tropicum were the most common fungal species associated with these Indian birds. Maximum occurrence of fungi (47%) was recorded on domestic chickens and the least number of keratinophilic fungi was isolated from the domestic pigeon and duck. The average number of fungi per bird was found to be the 0.44.

  6. Ionizing radiation and wild birds: a review

    International Nuclear Information System (INIS)

    Mellinger, P.J.; Schultz, V.

    1975-01-01

    Since the first atomic explosion, 16 July 1945 at the Trinity Site in south-central New Mexico, the impact of ionizing radiation on bird populations has been of concern to a few individuals. The proliferation of nuclear power plants has increased public concern as to possible deleterious effects of nuclear power plant operation on resident and migratory bird populations. Literature involving wild birds and ionizing radiation is not readily available, and only a few studies have been anywhere near comprehensive, with most effort directed towards monitoring radionuclide concentration in birds. The objective of the paper is to document the literature on wild birds and ionizing radiation including a brief description of pertinent papers

  7. The Origin and Diversification of Birds.

    Science.gov (United States)

    Brusatte, Stephen L; O'Connor, Jingmai K; Jarvis, Erich D

    2015-10-05

    Birds are one of the most recognizable and diverse groups of modern vertebrates. Over the past two decades, a wealth of new fossil discoveries and phylogenetic and macroevolutionary studies has transformed our understanding of how birds originated and became so successful. Birds evolved from theropod dinosaurs during the Jurassic (around 165-150 million years ago) and their classic small, lightweight, feathered, and winged body plan was pieced together gradually over tens of millions of years of evolution rather than in one burst of innovation. Early birds diversified throughout the Jurassic and Cretaceous, becoming capable fliers with supercharged growth rates, but were decimated at the end-Cretaceous extinction alongside their close dinosaurian relatives. After the mass extinction, modern birds (members of the avian crown group) explosively diversified, culminating in more than 10,000 species distributed worldwide today. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Influence of restored koa in supporting bird communities

    Science.gov (United States)

    Camp, Richard J.; Paxton, Eben H.; Yelenik, Stephanie G.

    2017-01-01

    Deforestation of Hawaiian forests has adversely impacted native wildlife, including forest birds, bats and arthropods. Restoration activities have included reforestation with the native koa (Acacia koa), a dominant canopy tree species that is easy to propagate, has high survivorship, and has fast growth rates. We review recent research describing the ecological benefits of koa restoration on wildlife colonization/use, plant dispersal, and native plant recruitment. In general, planting monotypic koa stands can provide forest habitats for species that need them but does not automatically lead to natural regeneration of a diverse forest species assemblage and may require additional restoration activities such as outplanting of other native plants and alien grass control to achieve more natural forest systems. Although early signs of forest and wildlife recovery have been encouraging, the goals of restoration for wildlife conservation versus commercial grade harvesting require different restoration methods.

  9. A longitudinal study of Steller sea lion natality rates in the Gulf of Alaska with comparisons to census data.

    Directory of Open Access Journals (Sweden)

    John M Maniscalco

    Full Text Available Steller sea lion (Eumetopias jubatus numbers in the Western Distinct Population Segment are beginning to recover following the dramatic decline that began in the 1970s and ended around the turn of the century. Low female reproductive rates (natality may have contributed to the decline and remain an issue of concern for this population. During the 2000s we found high natality among Steller sea lions in the Gulf of Alaska indicating a healthy population. This study extends these previous estimates over an additional three years and tests for interannual variations and long-term trends. We further examine the proportions of pups to adult females observed on the rookery and nearby haulouts during the birthing season to assess whether census data can be used to estimate natality. Open robust design multistate models were built and tested using Program MARK to estimate survival, resighting, and state transition probabilities in addition to other parameters dependent on whether or not a female gave birth in the previous year. Natality was estimated at 70% with some evidence of interannual variation but a long-term increasing or decreasing trend was not supported by the data. Bootstrap and regression comparisons of census data with natality estimates revealed no correlation between the two methods suggesting that census data are not an appropriate proxy for natality in this species. Longitudinal studies of individual animals are an appropriate method for estimating vital rates in species with variable detection over time such as the Steller sea lion. This work indicates that natality remains high in this region and is consistent with a population in recovery.

  10. Spanish juniper gain expansion opportunities by counting on a functionally diverse dispersal assemblage community.

    Science.gov (United States)

    Escribano-Ávila, Gema; Pías, Beatriz; Sanz-Pérez, Virginia; Virgós, Emilio; Escudero, Adrián; Valladares, Fernando

    2013-10-01

    Seed dispersal is typically performed by a diverse array of species assemblages with different behavioral and morphological traits which determine dispersal quality (DQ, defined as the probability of recruitment of a dispersed seed). Fate of ecosystems to ongoing environmental changes is critically dependent on dispersal and mainly on DQ in novel scenarios. We assess here the DQ, thus the multiplicative effect of germination and survival probability to the first 3 years of life, for seeds dispersed by several bird species (Turdus spp.) and carnivores (Vulpes vulpes, Martes foina) in mature woodland remnants of Spanish juniper (Juniperus thurifera) and old fields which are being colonized by this species. Results showed that DQ was similar in mature woodlands and old fields. Germination rate for seeds dispersed by carnivores (11.5%) and thrushes (9.12%) was similar, however, interacted with microhabitat suitability. Seeds dispersed by carnivores reach the maximum germination rate on shrubs (16%), whereas seeds dispersed by thrushes did on female juniper canopies (15.5) indicating that each group of dispersers performed a directed dispersal. This directional effect was diluted when survival probability was considered: thrushes selected smaller seeds which had higher mortality in the seedling stage (70%) in relation to seedlings dispersed by carnivores (40%). Overall, thrushes resulted low-quality dispersers which provided a probability or recruitment of 2.5%, while a seed dispersed by carnivores had a probability of recruitment of 6.5%. Our findings show that generalist dispersers (i.e., carnivores) can provide a higher probability of recruitment than specialized dispersers (i.e., Turdus spp.). However, generalist species are usually opportunistic dispersers as their role as seed dispersers is dependent on the availability of trophic resources and species feeding preferences. As a result, J. thurifera dispersal community is composed by two functional groups of

  11. Coping with power dispersion?

    DEFF Research Database (Denmark)

    2014-01-01

    The last decades have witnessed a significant shift in policy competences away from central governments in Europe. The reallocation of competences spans over three dimensions: upwards; sideways; and downwards. This collection takes the dispersion of powers as a starting point and seeks to assess...... how the actors involved cope with the new configurations. In this introduction, we discuss the conceptualization of power dispersion and highlight the ways in which the contributions add to this research agenda. We then outline some general conclusions and end by indicating future avenues of research....... Taken together, the collection contributes some answers to the challenge of defining and measuring – in a comparative way – the control and co-ordination mechanisms which power dispersion generates. It also explores the tension between political actors' quest for autonomy and the acknowledgement...

  12. Cumulative Effects of Barriers on the Movements of Forest Birds

    Directory of Open Access Journals (Sweden)

    Marc Bélisle

    2002-01-01

    Full Text Available Although there is a consensus of opinion that habitat fragmentation has deleterious effects on animal populations, primarily by inhibiting dispersal among remaining patches, there have been few explicit demonstrations of the ways by which degraded habitats actually constrain individual movement. Two impediments are primarily responsible for this paucity: it is difficult to separate the effects of habitat fragmentation (configuration from habitat loss (composition, and conventional measures of fragmented habitats are assumed to be, but probably are not, isotropic. We addressed these limitations by standardizing differences in forest cover in a clearly anisotropic configuration of habitat fragmentation by conducting a homing experiment with three species of forest birds in the Bow Valley of Banff National Park, Canada. Birds were translocated (1.2-3.5  km either parallel or perpendicular to four/five parallel barriers that are assumed to impede the cross-valley travel of forest-dependent animals. Taken together, individuals exhibited longer return times when they were translocated across these barriers, but differences among species suggest a more complex interpretation. A long-distance migrant (Yellow-rumped Warbler, Dendroica coronata behaved as predicted, but a short-distance migrant (Golden-crowned Kinglet, Regulus satrapa was indifferent to barrier configuration. A resident (Red-breasted Nuthatch, Sitta canadensis exhibited longer return times when it was translocated parallel to the barriers. Our results suggest that an anisotropic arrangement of small, open areas in fragmented landscapes can have a cumulative barrier effect on the movement of forest animals, but that both modelers and managers will have to acknowledge potentially counterintuitive differences among species to predict the effect that these may have on individual movement and, ultimately, dispersal.

  13. Toward Electoral Security: Experiences from KwaZulu-Natal Höhere Sicherheit bei Wahlen: Erfahrungen aus KwaZulu-Natal

    Directory of Open Access Journals (Sweden)

    Kristine Höglund

    2011-01-01

    Full Text Available There is a growing recognition of the dangers of electoral violence. Yet, the theoretical foundation for systematic research and for adequate policy is still underdeveloped. This article aims to develop the theoretical understandings of strategies to manage and prevent electoral violence. This is accomplished by integrating research conducted within the two academic discourses on democratization and conflict management and also by drawing on the experiences from the conflict-ridden province KwaZulu-Natal in South Africa. The five strategies identified are monitoring, mediation, legal measures, law enforcement and self-regulating practices. In the article, the functions and mechanisms of the strategies are discussed. In addition, we analyse the limitations and usefulness of each of the strategies in turn and also provide suggestions on how to improve electoral security.Gewaltsame Auseinandersetzungen bei Wahlen werden zunehmend als Gefahr erkannt. Dennoch sind die theoretischen Grundlagen systematischer Forschungen zu diesem Phänomen, die zu angemessenen politischen Handlungsweisen beitragen könnten, immer noch ungenügend entwickelt. Dieser Beitrag zielt darauf ab, einen theoretischen Hintergrund für Strategien zum Umgang mit Gewalt bei Wahlen und zur Prävention zu entwickeln. Zu diesem Zweck kombinieren die Autorinnen Ergebnisse zweier Forschungsbereiche – der Demokratisierungsforschung und der Forschung zum Konfliktmanagement – und ziehen außerdem Erfahrungen aus der konfliktbeladenen südafrikanischen Provinz KwaZulu-Natal heran. Sie identifizieren fünf Strategien: Monitoring, Mediation, gesetzliche Maßnahmen, Sanktionierung und Selbsthilfepraktiken. Die Autorinnen diskutieren die Wirkungsweisen und Erfolgsaussichten, aber auch die Grenzen dieser Strategien und machen einige konkrete Vorschläge zur Erhöhung der Sicherheit bei Wahlen.

  14. Biosecurity and bird movement practices in upland game bird facilities in the United States.

    Science.gov (United States)

    Slota, Katharine E; Hill, Ashley E; Keefe, Thomas J; Bowen, Richard A; Pabilonia, Kristy L

    2011-06-01

    Since 1996, the emergence of Asian-origin highly pathogenic avian influenza subtype H5N1 has spurred great concern for the global poultry industry. In the United States, there is concern over the potential of a foreign avian disease incursion into the country. Noncommercial poultry operations, such as upland game bird facilities in the United States, may serve as a potential source of avian disease introduction to other bird populations including the commercial poultry industry, backyard flocks, or wildlife. In order to evaluate how to prevent disease transmission from these facilities to other populations, we examined biosecurity practices and bird movement within the upland game bird industry in the United States. Persons that held a current permit to keep, breed, or release upland game birds were surveyed for information on biosecurity practices, flock and release environments, and bird movement parameters. Biosecurity practices vary greatly among permit holders. Many facilities allow for interaction between wild birds and pen-reared birds, and there is regular long-distance movement of live adult birds among facilities. Results suggest that upland game bird facilities should be targeted for biosecurity education and disease surveillance efforts.

  15. Pet birds II. Complementary diagnostic procedures

    International Nuclear Information System (INIS)

    Beregi, A.; Molnar, V.; Felkai, F.; Biro, F.

    1997-01-01

    Microscopical examinations are useful in detecting bacteria from droppings and body fluids. Antimicrobial susceptibility tests are also used to perform antimicrobial therapy. Parasitological examinations can also be done on pet birds. Hematological examinations are not very common because of the difficulties in determining the normal serum values that might vary by species and sexes. The vena cutanea ulnaris is the best vein for drawing blood from a pet bird but nail clipping for this purpose is also widely used. The most common and basic complementary examination method is radiology. Birds can be radiographed without anesthesia. Ventrodorsal and latero-lateral pictures are required. The right positioning and setting the adequate values is the most important. Contrast radiographs can also be made on birds. Endoscopy is widely used for sex determination but also can be used for the examination of abdominal organs. Ultrasound examination of pet birds is not a common method because of the difficulties provided by the air sacs. ECG is not a widely used method either because of the high heart beat frequency of birds. Other methods such as necropsy, cytological, histological and toxicological examinations can also be performed on pet birds

  16. Impact of estuarine pollution on birds

    Science.gov (United States)

    Blus, L.J.; Wiemeyer, Stanley N.; Kerwin, J.A.; Stendell, R.C.; Ohlendorf, H.M.; Stickel, L.F.

    1977-01-01

    Pollution of estuaries affects bird populations indirectly through changes in habitat and food supply. The multi-factor pollution of Chesapeake Bay has resulted in diminution of submerged aquatic plants and consequent change in food habits of the canvasback duck. Although dredge-spoil operations can improve wildlife habitat, they often result in its demise. Pollution of estuaries also affects birds directly, through chemical toxication, which may result in outright mortality or in reproductive impairment. Lead from industrial sources and roadways enters the estuaries and is accumulated in tissues of birds. Lead pellets deposited in estuaries as a result of hunting are consumed by ducks with sufficient frequency .to result m large annual die-offs from lead poisoning. Fish in certain areas, usually near industrial sources, may contain levels of mercury high enough to be hazardous to birds that consume them. Other heavy metals are present in estuarine birds, but their significance is poorly known. Oil exerts lethal or sublethal effects on birds by oiling their feathers, oiling eggs and young by contaminated parents, and by ingestion of oil-contaminated food. Organochlorine chemicals, of both agricultural and industrial origin, travel through the food chains and reach harmful levels in susceptible species of birds in certain estuarine ecosystems. Both outright mortality and reproductive impairment have occurred.

  17. Fine-scale movement decisions of tropical forest birds in a fragmented landscape.

    Science.gov (United States)

    Gillies, Cameron S; Beyer, Hawthorne L; St Clair, Colleen Cassady

    2011-04-01

    The persistence of forest-dependent species in fragmented landscapes is fundamentally linked to the movement of individuals among subpopulations. The paths taken by dispersing individuals can be considered a series of steps built from individual route choices. Despite the importance of these fine-scale movement decisions, it has proved difficult to collect such data that reveal how forest birds move in novel landscapes. We collected unprecedented route information about the movement of translocated forest birds from two species in the highly fragmented tropical dry forest of Costa Rica. In this pasture-dominated landscape, forest remains in patches or riparian corridors, with lesser amounts of living fencerows and individual trees or "stepping stones." We used step selection functions to quantify how route choice was influenced by these habitat elements. We found that the amount of risk these birds were willing to take by crossing open habitat was context dependent. The forest-specialist Barred Antshrike (Thamnophilus doliatus) exhibited stronger selection for forested routes when moving in novel landscapes distant from its territory relative to locations closer to its territory. It also selected forested routes when its step originated in forest habitat. It preferred steps ending in stepping stones when the available routes had little forest cover, but avoided them when routes had greater forest cover. The forest-generalist Rufous-naped Wren (Campylorhynchus rufinucha) preferred steps that contained more pasture, but only when starting from non-forest habitats. Our results showed that forested corridors (i.e., riparian corridors) best facilitated the movement of a sensitive forest specialist through this fragmented landscape. They also suggested that stepping stones can be important in highly fragmented forests with little remaining forest cover. We expect that naturally dispersing birds and species with greater forest dependence would exhibit even stronger

  18. Proto-planetary disc evolution and dispersal

    Science.gov (United States)

    Rosotti, Giovanni Pietro

    2015-05-01

    rates and is therefore the ideal candidate for driving disc evolution. Another process that can influence discs is a close encounter with another star. In this thesis we develop a model to study the effect of stellar dynamics in the natal stellar cluster on the discs, following for the first time at the same time the stellar dynamics together with the evolution of the discs. We find that, although close encounters with stars are unlikely to change significantly the mass of a disc, they can change substantially its size, hence imposing an upper limit on the observed disc radii. Finally, we investigated in this thesis whether discs can be reformed after their dispersal. If a star happens to be in a region that is currently forming stars, it can accrete material from the interstellar medium. This mechanism may result in the production of "second generation" discs such that in a given star forming region a few percent of stars may still possess a disc, in tentative agreement with observations of so called "old accretors", which are difficult to explain within the current paradigm of disc evolution and dispersal.

  19. Interface, a dispersed architecture

    NARCIS (Netherlands)

    Vissers, C.A.

    1976-01-01

    Past and current specification techniques use timing diagrams and written text to describe the phenomenology of an interface. This paper treats an interface as the architecture of a number of processes, which are dispersed over the related system parts and the message path. This approach yields a

  20. Psychorheology of food dispersions

    Czech Academy of Sciences Publication Activity Database

    Štern, Petr; Panovská, Z.; Pokorný, J.

    2010-01-01

    Roč. 58, č. 1 (2010), s. 29-35 ISSN 0042-790X R&D Projects: GA AV ČR IAA2060404 Institutional research plan: CEZ:AV0Z20600510 Keywords : psychorheology * food dispersions * tomato ketchup * rheology * sensory analysis Subject RIV: BK - Fluid Dynamics Impact factor: 0.553, year: 2010

  1. Dispersal of sticky particles

    Science.gov (United States)

    Reddy, Ramana; Kumar, Sanjeev

    2007-12-01

    In this paper, we show through simulations that when sticky particles are broken continually, particles are dispersed into fine dust only if they are present in a narrow range of volume fractions. The upper limit of this range is 0.20 in the 2D and 0.10 in the 3D space. An increase in the dimensionality of space reduces the upper limit nearly by a factor of two. This scaling holds for dispersal of particles in hyperdimensional space of dimensions up to ten, the maximum dimension studied in this work. The maximum values of volume fractions obtained are significantly lower than those required for close packing and random packing of discs in 2D and spheres in 3D space. These values are also smaller than those required for critical phenomena of cluster percolation. The results obtained are attributed to merger cascades of sticky particles, triggered by breakup events. A simple theory that incorporates this cascade is developed to quantitatively explain the observed scaling of the upper limit with the dimensionality of space. The theory also captures the dynamics of the dispersal process in the corresponding range of particle volume fractions. The theory suggests that cascades of order one and two predominantly decide the upper limit for complete dispersal of particles.

  2. Nem bandidos nem trabalhadores baratos: Trajetórias de jovens da periferia de Natal

    Directory of Open Access Journals (Sweden)

    Livia de Tommasi

    2012-01-01

    Full Text Available O artigo analisa a trajetória de jovens de um grupo de hip-hop na periferia de Natal, utilizando como ferramenta o conceito de ‘governamentalidade’ tal como tratado por Foucault. A narrativa dos jovens revela como eles se movimentam entre múltiplas experiências urbanas, procurando fugir do destino de grupo ‘de risco’ (tornar-se ‘mão de obra barata’ ou criminosos fazendo arte como forma de resistência. A análise propõe uma abordagem da juventude não como uma categoria analítica, um sujeito ou ator social, mas como um campo de intervenção que tem despertado interesse e recebido investimentos públicos e privados.  Neither Cheap Workforce nor Outlaws: Trajectories of Youngsters in the Outskirts of Natal examines the story of the young members of a hip-hop group in the Northeastern Brazil according to Foucault’s concept of ‘governmentality’. Their narrative reveals the way they move between multiple urban experiences trying to escape from their fate as “risk group” (that is, to become “cheap workforce” or criminals, using art as a form of resistance. We approach youth less as an analytical category, a subject or a social actor and rather as a field of intervention that has attracted attention and received public and private investments. Key words: governmentality, youth, hip-hop, periphery, Natal

  3. The Association of Molecular Gas and Natal Super Star Clusters in Henize 2–10

    Science.gov (United States)

    Johnson, Kelsey E.; Brogan, Crystal L.; Indebetouw, Remy; Testi, Leonardo; Wilner, David J.; Reines, Amy E.; Chen, C.-H. Rosie; Vanzi, Leonardo

    2018-02-01

    We present ALMA observations of the dwarf starburst galaxy He 2–10 in combination with previous SMA CO observations to probe the molecular environments of natal super star clusters (SSCs). These observations include the HCO+(1-0), HCN(1-0), HNC(1-0), and CCH(1-0) molecular lines, as well as 88 GHz continuum with a spatial resolution of 1\\buildrel{\\prime\\prime}\\over{.} 7× 1\\buildrel{\\prime\\prime}\\over{.} 6. After correcting for the contribution from free–free emission to the 88 GHz continuum flux density (∼60% of the 88 GHz emission), we derive a total gas mass for He 2–10 of {M}{gas}=4{--}6× {10}8 M ⊙, roughly 5%–20% of the dynamical mass. Based on a principle component analysis, HCO+ is found to be the best “general” tracer of molecular emission. The line widths and luminosities of the CO emission suggests that the molecular clouds could either be as small as ∼8 pc, or alternately have enhanced line widths. The CO emission and 88 GHz continuum are anti-correlated, suggesting that either the dust and molecular gas are not cospatial, which could reflect that the 88 GHz continuum is dominated by free–free emission. The CO and CCH emission are also relatively anti-correlated, which is consistent with the CCH being photo-enhanced, and/or the CO being dissociated in the regions near the natal SSCs. The molecular line ratios of regions containing the natal star clusters are different from the line ratios observed for regions elsewhere in the galaxy. In particular, the regions with thermal radio emission all have {CO}(2{--}1)/{{HCO}}+(1-0)correlated with the evolutionary stage of the clusters.

  4. Failure of post-natal ductus arteriosus closure in prostaglandin transporter-deficient mice

    Science.gov (United States)

    Chang, Hee-Yoon; Locker, Joseph; Lu, Run; Schuster, Victor L.

    2010-01-01

    Background Prostaglandin E2 (PGE2) plays a major role both in maintaining patency of the fetal ductus arteriosus (DA) and in closure of the DA after birth. The rate- limiting step in PGE2 signal termination is PGE2 uptake by the transporter PGT. Methods and results To determine the role of PGT in DA closure, we used a gene-targeting strategy to produce mice in which PGT exon 1 was flanked by loxP sites. Successful targeting was obtained since neither mice hypomorphic at the PGT allele (PGT Neo/Neo) nor global PGT knockout mice (PGT −/−) exhibited PGT protein expression; moreover, embryonic fibroblasts isolated from targeted mice failed to exhibit carrier-mediated PGE2 uptake. Although born in a normal Mendelian ratio, no PGT −/− mice survived past post-natal day 1, and no PGT Neo/Neo mice survived past post-natal day 2. Necropsy revealed patent DA with normal intimal thickening but with dilated cardiac chambers. Both PGT Neo/Neo and PGT −/− mice could be rescued through the post-natal period by giving the mother indomethacin before birth. Rescued mice grew normally and had no abnormalities by gross and microscopic post-mortem analysis. In accord with PGT’s known role in metabolizing PGE2, rescued adult PGT −/− mice had lower plasma PGE2 metabolite levels, and higher urinary PGE2 excretion rates, than wild type mice. Conclusions PGT plays a critical role in closure of the DA after birth by ensuring a reduction in local and/or circulating PGE2 concentrations. PMID:20083684

  5. Implementation of a micro hydropower supply scheme in the Kwazulu-Natal Drakensberg

    International Nuclear Information System (INIS)

    Dooge, G.R.

    1997-01-01

    Eskom has implemented a 5 kW micro hydropower supply scheme in the Kwazulu-Natal Drakensberg. The scheme supplies electrical power to five schools using a Single Wire Earth Return (SWER) transmission line. This paper describes the implementation of the scheme and covers the social aspects, the mechanical, civil and electrical works, and also scheme economics. The main aim of this project was to obtain experience in the design and implementation of a micro hydro system, both technically and socially, so that the technology could be used with confidence in Eskom's non-grid electrification programme. 5 refs., 3 figs

  6. Rare association of hyper IgE syndrome with cervical rib and natal teeth

    Directory of Open Access Journals (Sweden)

    Roshan Anupama

    2009-01-01

    Full Text Available Hyper IgE syndrome (HIES is a rare immunodeficiency syndrome characterized by a triad of cutaneous abscesses, mostly caused by Staphylococus aureus; pneumonia; and raised IgE levels. Nonimmunological associations include course facial features, multiple bone fractures, joint hyperextensibility, and retained primary dentition. Patients require long-term antibiotic therapy. We report here a classical case of HIES with rare associations of natal teeth, bilateral cervical ribs, and conductive deafness. The patient was being treated with monteleukast and dapsone.

  7. An investigation into techniques for reducing doses from neo-natal radiographic examinations

    Energy Technology Data Exchange (ETDEWEB)

    Wraith, C.M.; Martin, C.J. [Aberdeen Royal Hospitals NHS Trust (United Kingdom). Dept. of Bio-Medical Physics and Bio-Engineering; Stockdale, E.J.N.; McDonald, S.; Farquhar, B. [Royal Aberdeen Children`s Hospital (United Kingdom)

    1995-10-01

    A survey of radiation doses received by infants having radiography in a neo-natal unit was undertaken at Aberdeen Maternity Hospital. Options for dose reduction recommended by the CEC Lake Starnberg Group were investigated. Techniques were implemented for clinical evaluation after assessments of image quality with test objects and phantoms. Clinical image quality of radiographs was evaluated by paediatric radiologists using CEC criteria. Results revealed a clear relationship between entrance dose and patient weight, indicating that reference doses for infants could be linked to weight. (author).

  8. A Rb-Sr isotope study of a young granite sheet at Marble Delta, southern Natal

    International Nuclear Information System (INIS)

    Naidoo, D.D.; Eglington, B.M.; Harmer, R.E.

    1989-01-01

    Rb-Sr isotope data are presented for two apophyses of a granite sheet intrusive into marble at Marble Delta, southern Natal. Granite samples collected near the margins of these apophyses contain calcite and are thought to have been contaminated by the marble during intrusion of the granite magma. In contrast, those further away from contacts lack calcite. The 'uncontaminated' granite samples define an isochron date of 899 ± 11 Ma. This data is thought to represent the intrusive age of the granite sheet. 11 refs., 5 figs., 2 tabs

  9. Villes et structures spatiales élémentaires du KwaZulu-Natal

    Directory of Open Access Journals (Sweden)

    Fabrice Folio

    2004-12-01

    Full Text Available However significant the legacy of former segregational policies in the spatial organisation of South African cities, it is important to include other basic spatial structures that have often been minimised. That is the aim of this paper. The towns in KwaZulu-Natal province provide a strong illustration of this point. The urban entities in the province can be differentiated by several criteria – either historical or contemporary – that are not always related to apartheid policy. The towns are underpinned by basic structures that organise the province. These structures are determined not only by racial discrimination, but also by economics. Recent developments seem to reinforce this trend.

  10. Le Dépistage Prénatal Non Invasif de la Trisomie 21 : le DPNI

    OpenAIRE

    Fabre Belloin, Clémence

    2015-01-01

    Background: NIPT, Non-Invasive Pre-natal Testing, is a technological advance in the detection of fetal chromosomal aneuploidies, the most common of which is Down Syndrome. NIPT analyses cell-free fetal DNA in the blood of a pregnant woman. Its high sensitivity (99.1%) and specificity (99.9%) make that test a performance to the actual screening (Sensitivity = 85%, Specificity = 1/30). Fetal karyotyping is obtained by invasive procedure but nevertheless carries a risk of miscarriage of about 0....

  11. KwaZulu-Natal coastal erosion events of 2006/2007 and 2011: A predictive tool?

    OpenAIRE

    Alan Smith; Lisa A. Guastella; Andrew A. Mather; Simon C. Bundy; Ivan D. Haigh

    2013-01-01

    Severe coastal erosion occurred along the KwaZulu-Natal coastline between mid-May and November 2011. Analysis of this erosion event and comparison with previous coastal erosion events in 2006/2007 offered the opportunity to extend the understanding of the time and place of coastal erosion strikes. The swells that drove the erosion hotspots of the 2011 erosion season were relatively low (significant wave heights were between 2 m and 4.5 m) but of long duration. Although swell height was import...

  12. Development through rural advancement, with special reference to Kwazulu-Natal

    OpenAIRE

    2012-01-01

    M.Comm. The aim of this study was to analyse and discuss the importance of rural advancement in the development of developing regions or countries, and KwaZulu-Natal was used as a case study. The literature focused on the backwardness of the rural areas and the importance of rural advancement for the development of less developed regions or countries. Development cannot be said to have taken place unless people's lives in general have improved. Large parts of developing regions or countrie...

  13. Black rhinoceros Diceros bicomis capture, transportation and boma management by the Natal Parks Board

    Directory of Open Access Journals (Sweden)

    R.R. Henwood

    1989-10-01

    Full Text Available Selected Papers from the Rhinoceros Conservation Workshop, Skukuza, Kruger National Park,31 August – 4 September 1988 The procedure used by the Natal Parks Board in the capture of black rhinoceros Diceros bicomis minor (Drummond, 1876 is outlined. It is emphasised that a successful capture operation requires careful planning and should not be attempted by the uninitiated or by parties who have little or no experience. Dosages of drugs are given, the darting and actual capture procedures highlighted, and aspects of transport and practical boma management are described.

  14. The impact of anthropogenic food supply on fruit consumption by dusky-legged guan (Penelope obscura Temminck, 1815: potential effects on seed dispersal in an Atlantic forest area

    Directory of Open Access Journals (Sweden)

    J. Vasconcellos-Neto

    Full Text Available Abstract Frugivorous birds are important seed dispersers and influence the recruitment of many plant species in the rainforest. The efficiency of this dispersal generally depends on environment quality, bird species, richness and diversity of resources, and low levels of anthropogenic disturbance. In this study, we compared the sighting number of dusky-legged guans (Penelope obscura by km and their movement in two areas of Serra do Japi, one around the administrative base (Base where birds received anthropogenic food and a pristine area (DAE with no anthropogenic resource. We also compared the richness of native seeds in feces of birds living in these two areas. Although the abundance of P. obscura was higher in the Base, these individuals moved less, dispersed 80% fewer species of plants and consumed 30% fewer seeds than individuals from DAE. The rarefaction indicated a low richness in the frugivorous diet of birds from the Base when compared to the populations from DAE. We conclude that human food supply can interfere in the behavior of these birds and in the richness of native seeds dispersed.

  15. Spotted fever group rickettsiae in ticks of migratory birds in Romania.

    Science.gov (United States)

    Mărcuţan, Ioan-Daniel; Kalmár, Zsuzsa; Ionică, Angela Monica; D'Amico, Gianluca; Mihalca, Andrei Daniel; Vasile, Cozma; Sándor, Attila D

    2016-05-20

    Birds are important hosts and dispersers of parasitic arthropods and vector-borne zoonotic pathogens. Particularly migratory species may carry these parasites over long distances in short time periods. Migratory hotspots present ideal conditions to get a snapshot of parasite and pathogen diversity of birds migrating between continents. The aim of this study was to investigate the presence and diversity of Rickettsia spp. in ticks collected from birds at a migratory hot-spot in the Danube Delta, Romania, eastern Europe. DNA was extracted from ticks that were collected from migratory birds in the Danube Delta during migratory seasons in 2011-2012. Two 360 bp  fragments of the 16S ribosomal RNA gene and a 381 bp  fragment Gene gltA were PCR amplified and analyzed by sequence analysis (performed at Macrogen Europe, Amsterdam, The Netherlands). Nucleotide sequences were compared to reference sequences available in the GenBank database, using Basic Local Alignment Search Tool. Four hundred ticks of four different species were found on 11 bird species. The prevalence of Rickettsia spp. infection was 14 % (56/400, CI: 11.7-29.1), with significantly more nymphs hosting rickettsial infection compared to larvae (48 vs 7; P birds migrating through eastern Europe may carry ticks infected with a high diversity of rickettsial pathogens, with four Rickettsia spp. recorded. Migratory direction was important for pathogen burden, with seasonal differences in the occurrence of individual Rickettsia species. Here we report the first individual records of different Rickettsia spp. in H. concinna (R. monacensis), I. arboricola (R. helvetica, R. massiliae) and I. redikorzevi (R. helvetica) and also the first geographical record of occurrence of R. massiliae in Romania, representing the easternmost observation on the continent.

  16. 19 CFR 10.76 - Game animals and birds.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Game animals and birds. 10.76 Section 10.76... TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. General Provisions Animals and Birds § 10.76 Game animals and birds. (a) The following classes of live game animals and birds may be...

  17. 50 CFR 20.37 - Custody of birds of another.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Custody of birds of another. 20.37 Section... WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Possession § 20.37 Custody of birds of another. No person shall receive or have in custody any migratory game birds belonging to another person unless such...

  18. 50 CFR 20.62 - Importation of birds of another.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Importation of birds of another. 20.62... WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Importations § 20.62 Importation of birds of another. No person shall import migratory game birds belonging to another person. ...

  19. 45 CFR 670.20 - Designation of native birds.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Designation of native birds. 670.20 Section 670.20... CONSERVATION OF ANTARCTIC ANIMALS AND PLANTS Native Mammals, Birds, Plants, and Invertebrates § 670.20 Designation of native birds. The following are designated native birds: Albatross Black-browed—Diomedea...

  20. 50 CFR 20.38 - Possession of live birds.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Possession of live birds. 20.38 Section 20... WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Possession § 20.38 Possession of live birds. Every migratory game bird wounded by hunting and reduced to possession by the hunter shall be immediately killed...

  1. Avian Bornavirus in Free-Ranging Psittacine Birds, Brazil

    Science.gov (United States)

    Encinas-Nagel, Nuri; Enderlein, Dirk; Piepenbring, Anne; Herden, Christiane; Heffels-Redmann, Ursula; Felippe, Paulo A.N.; Arns, Clarice; Hafez, Hafez M.

    2014-01-01

    Avian bornavirus (ABV) has been identified as the cause of proventricular dilatation disease in birds, but the virus is also found in healthy birds. Most studies of ABV have focused on captive birds. We investigated 86 free-ranging psittacine birds in Brazil and found evidence for natural, long-term ABV infection. PMID:25417715

  2. 50 CFR 20.42 - Transportation of birds of another.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Transportation of birds of another. 20.42... WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Transportation Within the United States § 20.42 Transportation of birds of another. No person shall transport migratory game birds belonging to another person...

  3. Effects of prescribed burns on wintering cavity-nesting birds

    Science.gov (United States)

    Heather L. Bateman; Margaret A. O' Connell

    2006-01-01

    Primary cavity-nesting birds play a critical role in forest ecosystems by excavating cavities later used by other birds and mammals as nesting or roosting sites. Several species of cavity-nesting birds are non-migratory residents and consequently subject to winter conditions. We conducted winter bird counts from 1998 to 2000 to examine the abundance and habitat...

  4. Biology: Birds and butterflies in climatic debt

    NARCIS (Netherlands)

    Visser, M.E.

    2012-01-01

    A European-wide analysis of changing species distributions shows that butterflies outrun birds in the race to move northwards in response to climate change, but that neither group keeps up with increasing temperatures.

  5. The function of migratory bird calls

    DEFF Research Database (Denmark)

    Reichl, Thomas; Andersen, Bent Bach; Larsen, Ole Næsbye

    The function of migratory bird calls: do they influence orientation and navigation?   Thomas Reichl1, Bent Bach Andersen2, Ole Naesbye Larsen2, Henrik Mouritsen1   1Institute of Biology, University of Oldenburg, Oldenburg, D-26111 Oldenburg, Germany 2Institute of Biology, University of Southern...... migration and to stimulate migratory restlessness in conspecifics. We wished to test if conspecific flight calls influence the flight direction of a nocturnal migrant, the European Robin (Erithacus rubecula), i.e. if flight calls help migrants keeping course. Wild caught birds showing migratory restlessness...... the experimental bird could be activated successively to simulate a migrating Robin cruising E-W, W-E, S-N or N-S at a chosen height (mostly about 40 m), at 10 m/s and emitting Robin flight calls of 80 dB(A) at 1 m. The simulated flight of a "ding" sound served as a control. During an experiment the bird was first...

  6. Birds - Spears and Didion Ranches [ds315

    Data.gov (United States)

    California Natural Resource Agency — These data are summary statistics of abundances of birds counted within 100-m radius circles with 10-minute point counts at 15 sample points within Spears and Didion...

  7. Birding Lessons and the Teachings of Cicadas.

    Science.gov (United States)

    Jardine, David W.

    1998-01-01

    Explores the ecological and pedagogical images hidden within a tale of the author's returning to the place where he grew up and going for a birding walk with some old friends. Contains 18 references. (DDR)

  8. Riparian Birds - Sierra Nevada Foothill [ds303

    Data.gov (United States)

    California Natural Resource Agency — These data are summary statistics of abundances of birds counted within 100-m radius circles with 10-minute point counts at multiple sample points along 36 randomly...

  9. Medication for Behavior Modification in Birds

    NARCIS (Netherlands)

    van Zeeland, Yvonne

    2018-01-01

    The use of behavior modifying drugs may be considered in birds with behavior problems, especially those refractory to behavior modification therapy and environmental management. To accomplish behavior change, a variety of drugs can be used, including psychoactive drugs, hormones, antihistamines,

  10. Chernobyl birds have smaller brains.

    Directory of Open Access Journals (Sweden)

    Anders Pape Møller

    2011-02-01

    Full Text Available Animals living in areas contaminated by radioactive material from Chernobyl suffer from increased oxidative stress and low levels of antioxidants. Therefore, normal development of the nervous system is jeopardized as reflected by high frequencies of developmental errors, reduced brain size and impaired cognitive abilities in humans. Alternatively, associations between psychological effects and radiation have been attributed to post-traumatic stress in humans.Here we used an extensive sample of 550 birds belonging to 48 species to test the prediction that even in the absence of post-traumatic stress, there is a negative association between relative brain size and level of background radiation. We found a negative association between brain size as reflected by external head volume and level of background radiation, independent of structural body size and body mass. The observed reduction in brain size in relation to background radiation amounted to 5% across the range of almost a factor 5,000 in radiation level. Species differed significantly in reduction in brain size with increasing background radiation, and brain size was the only morphological character that showed a negative relationship with radiation. Brain size was significantly smaller in yearlings than in older individuals.Low dose radiation can have significant effects on normal brain development as reflected by brain size and therefore potentially cognitive ability. The fact that brain size was smaller in yearlings than in older individuals implies that there was significant directional selection on brain size with individuals with larger brains experiencing a viability advantage.

  11. Analysis of forecasting malaria case with climatic factors as predictor in Mandailing Natal Regency: a time series study

    Science.gov (United States)

    Aulia, D.; Ayu, S. F.; Matondang, A.

    2018-01-01

    Malaria is the most contagious global concern. As a public health problem with outbreaks, affect the quality of life and economy, also could lead to death. Therefore, this research is to forecast malaria cases with climatic factors as predictors in Mandailing Natal Regency. The total number of positive malaria cases on January 2008 to December 2016 were taken from health department of Mandailing Natal Regency. Climates data such as rainfall, humidity, and temperature were taken from Center of Statistic Department of Mandailing Natal Regency. E-views ver. 9 is used to analyze this study. Autoregressive integrated average, ARIMA (0,1,1) (1,0,0)12 is the best model to explain the 67,2% variability data in time series study. Rainfall (P value = 0.0005), temperature (P value = 0,0029) and humidity (P value = 0.0001) are significant predictors for malaria transmission. Seasonal adjusted factor (SAF) in November and March shows peak for malaria cases.

  12. Birds of Sierra de Vallejo, Nayarit, Mexico

    OpenAIRE

    Figueroa-Esquivel, E.M.; Puebla-Olivares, F

    2014-01-01

    Sierra de Vallejo, is considered a priority region for conservation, and is strongly affected by anthropogenic pressures. The inventory of birds are refers to studies in near areas. This study is a concrete contribution of the birds of the mountain chain and north of it. We considered bibliographic records and databases available on the web with records of ocurrence and specimens of scientific collections. Also we perform point counts in different localities inside the...

  13. Coccidia of gallinaceous meat birds in Brazil

    OpenAIRE

    Teixeira, Marcel; Melo, Antônio Diego Brandão; Albuquerque, George Rego; Rocha, Patrícia Tironi; Monteiro, Jomar Patrício

    2015-01-01

    Coccidiosis is a disease that limits the production and marketing of gallinaceous birds in North America, especially quails, pheasants and chukar partridges. Virtually no research has been conducted in South America on the causative agents of diseases among these birds, including coccidia. The aim of this work was to make first observations on Eimeria spp. in the chukar partridge Alectoris chukar and the grey quail Coturnix coturnix, which are reared for meat in Brazil. Fecal and tissue sampl...

  14. GEOMETRICAL PARAMETERS OF EGGS IN BIRD SYSTEMATICS

    Directory of Open Access Journals (Sweden)

    Mityay I.S.

    2014-12-01

    Full Text Available Our ideas are based on the following assumptions. Egg as a standalone system is formed within another system, which is the body of the female. Both systems are implemented on the basis of a common genetic code. In this regard, for example, the dendrogram constructed by morphological criteria eggs should be approximately equal to those constructed by other molecular or morphological criteria adult birds. It should be noted that the dendrogram show only the degree of genetic similarity of taxa, therefore, the identity of materials depends on the number of analyzed criteria and their quality, ie, they should be the backbone. The greater the number of system-features will be included in the analysis and in one other case, the like are dendrogram. In other cases, we will have a fragmentary similarity, which is also very important when dealing with controversial issues. The main message of our research was to figure out the eligibility of usage the morphological characteristics of eggs as additional information in taxonomy and phylogeny of birds. Our studies show that the shape parameters of bird eggs show a stable attachment to certain types of birds and complex traits are species-specific. Dendrogram and diagrams built by the quantitative value of these signs, exhibit significant similarity with the dendrogram constructed by morphological, comparative anatomy, paleontology and molecular criteria for adult birds. This suggests the possibility of using morphological parameters eggs as additional information in dealing with taxonomy and phylogeny of birds.

  15. Eimeria tenella: host specificity in gallinaceous birds.

    Science.gov (United States)

    Vetterling, J M

    1976-02-01

    Eight species representing 8 genera of gallinaceous birds were used: Alectoris graeca; Colinus virginianus; Coturnix coturnix; Gallus gallus; Meleagris gallopavo; Numidia meleagris; Pavo cristatus; Phasianus colchicus. Three week-old birds were dosed with sporulated oocysts of Eimeria tenella Beltsville strain. At 4, 24, 48, 72, 96, 120 and 144, and 168 hr after inoculation, 1-3 infected birds and uninoculated controls of each species were killed by cardiac exsanguination. Pieces of intestines were fixed and examined for stages of E. tenella as stained paraffin sections or indirect fluorescent antibody preparations. Oocyst counts were made in droppings collected for the first 6 days of the patent period. Sporozoites were found in the lamina propria of some birds of 5 species at 4 hr postinoculation, but no stages were found thereafter except in the breeds of G. gallus and A. gracea. At 144 and 168 hr postinoculation, a few macrogametes were found in the ceca of 2 A. gracea, but no oocysts were found in the feces. No statistical difference was found between the number of oocysts produced/bird in the breeds of G. gallus examined. It is evident from these observations the E. tenella did not complete its life cycle in several close phylogenetic relatives of G. gallus, even though in other studies this parasite was found to complete its life cycle in cell cultures derived from the same birds.

  16. Impact of wind turbines on birds

    International Nuclear Information System (INIS)

    Clausager, I.; Nohr, H.

    1996-01-01

    The paper is a review of the present knowledge on impacts of wind turbines on birds, requested by the Danish Ministry of the Environment and Energy. The main conclusions of the review are, that in nearly all the studies so far the numbers of birds recorded colliding with wind turbines have been limited. Some studies indicate that stationary (breeding) birds inside the wind turbine area in the short run habituate to wind turbines, especially the noise and visual impacts, and that the risk for collision becomes low. However, some of the few more long term studies indicate that a negative impact may occur in later generations of breeding birds. In some studies a disturbance effect on bird species, which temporarily stay inside a wind turbine area in order to forage or rest, is observed. The degree of impact is species-specific. An effect is typically recorded inside a zone of up to 250-800 m, with geese and waders as the most sensitive groups of birds. (author)

  17. Magnetic Orientation in Birds and Other Animals

    Science.gov (United States)

    Wiltschko, Wolfgang

    The use of the geomagnetic field for compass orientation is widespread among animals, with two types of magnetic compass mechanisms described: an shape inclination compass in birds, turtles and salamanders and a shape polarity compass in arthropods, fishes and mammals. Additionally, some vertebrates appear to derive positional information from the total intensity and/or inclination of the geomagnetic field. For magnetoreception by animals, two models are currently discussed, the shape Radical Pair model assuming light-dependent processes by specialized photopigments, and the shape Magnetite hypothesis proposing magnetoreception by crystals of magnetite, Fe304. Behavioral experiments with migratory birds, testing them under monochromatic lights and subjecting them to a brief, strong pulse that could reverse the magnetization of magnetite particles, produced evidence for both mechanisms. However, monochromatic lights affect old, experienced and young birds alike, whereas the pulse affects only experienced birds, leaving young, inexperienced birds unaffected. These observations suggest that a radical pair mechanism provides birds with directional information for their innate magnetic compass and a magnetite-based mechanism possibly mediates information about total intensity for indicating position.

  18. Dispersed flow film boiling

    International Nuclear Information System (INIS)

    Andreani, M.; Yadigaroglu, G.

    1989-12-01

    Dispersed flow film boiling is the heat transfer regime that occurs at high void fractions in a heated channel. The way this transfer mode is modelled in the NRC computer codes (RELAP5 and TRAC) and the validity of the assumption and empirical correlations used is discussed. An extensive review of the theoretical and experimental work related with heat transfer to highly dispersed mixtures reveals the basic deficiencies of these models: the investigation refers mostly to the typical conditions of low rate bottom reflooding, since the simulation of this physical situation by the computer codes has often showed poor results. The alternative models that are available in the literature are reviewed, and their merits and limits are highlighted. The modification that could improve the physics of the models implemented in the codes are identified. (author) 13 figs., 123 refs

  19. Working document dispersion models

    International Nuclear Information System (INIS)

    Dop, H. van

    1988-01-01

    This report is a summary of the most important results from June 1985 of the collaboration of the RIVM (Dutch National Institute for Public Health and Environment Hygiene) and KNMI (Royal Dutch Meteorologic Institute) on the domain of dispersion models. It contains a short description of the actual SO x /NO x -model. Furthermore it contains recommendations for modifications of some numerical-mathematical aspects and an impulse to a more complete description of chemical processes in the atmosphere and the (wet) deposition process. A separate chapter is devoted to the preparation of meteorologic data which are relevant for dispersion as well as atmospheric chemistry and deposition. This report serves as working document for the final formulation of a acidifying- and oxidant-model. (H.W.). 69 refs.; 51 figs.; 13 tabs.; 3 schemes

  20. Spatially Dispersed Employee Recovery

    DEFF Research Database (Denmark)

    Hvass, Kristian Anders; Torfadóttir, Embla

    2014-01-01

    Employee recovery addresses either employee well-being or management's practices in aiding employees in recovering themselves following a service failure. This paper surveys the cabin crew at a small, European, low-cost carrier and investigates employees' perceptions of management practices to aid...... personnel achieve service recovery. Employee recovery within service research often focuses on front-line employees that work in a fixed location, however a contribution to the field is made by investigating the recovery of spatially dispersed personnel, such as operational personnel in the transport sector......, who have a work place away from a fixed or central location and have minimal management contact. Results suggest that the support employees receive from management, such as recognition, information sharing, training, and strategic awareness are all important for spatially dispersed front...

  1. Heat dispersion in rivers

    International Nuclear Information System (INIS)

    Shaw, T.L.

    1974-01-01

    One of the tasks of the Sonderforschungsbereich 80 is to study the dispersion of heat discharged into rivers and other bodies of water and to develop methods which permit prediction of detrimental effects caused by the heated discharges. In order to help the SFB 80 to specify this task, Dr. Shaw, lecturer of Civil Engineering at the Bristol University, conducted a literature survey on heat-dispersion studies during the two months which he spent as a visiting research fellow with the SFB 80 at the University of Karlsruhe in the summer of 1973. The following report is the outcome of this survey. It gives Dr. Shaw's assessment of the present state of knowledge - based almost exclusively on literature in the English language - and compares this with the knowledge required by river planners. The apparent discrepancy leads to suggestions for future research. Selected references as well as a representative bibliography can be found at the end of the report. (orig.) [de

  2. 9 CFR 95.30 - Restrictions on entry of products and byproducts of poultry, game birds, or other birds from...

    Science.gov (United States)

    2010-01-01

    ... byproducts of poultry, game birds, or other birds from regions where highly pathogenic avian influenza (HPAI... THE UNITED STATES § 95.30 Restrictions on entry of products and byproducts of poultry, game birds, or other birds from regions where highly pathogenic avian influenza (HPAI) subtype H5N1 exists. (a...

  3. Two decades of genetic profiling yields first evidence of natal philopatry and long-term fidelity to parturition sites in sharks

    KAUST Repository

    Feldheim, Kevin Andrew; Gruber, Samuel H.; DiBattista, Joseph; Babcock, Elizabeth A.; Kessel, Steven T.; Hendry, Andrew P.; Pikitch, Ellen K.; Ashley, Mary V.; Chapman, Demian D F

    2013-01-01

    in the 1993-1997 cohorts returned to give birth 14-17 years later, providing the first direct evidence of natal philopatry in the chondrichthyans. Long-term fidelity to specific nursery sites coupled with natal philopatry highlights the merits of emerging

  4. Neotropical Migratory Bird Communities in a Developing Pine Plantation

    Science.gov (United States)

    James G. Dickson; Richard N. Conner; J. Howard Williamson

    1993-01-01

    Birds were censused annually from 4 250-x80-in transects in a young pine plantation from age to 2 to 17 to assess changes in the bird community.Bird abundance was low and the bird communitry was the least diverse when the pine plantation was sparsely vegetated at age 2. As the plantation developed rapidly into the shrub stage, the bird communitry became more abundant...

  5. The Flight of Birds and Other Animals

    Directory of Open Access Journals (Sweden)

    Colin J. Pennycuick

    2015-09-01

    Full Text Available Methods of observing birds in flight now include training them to fly under known conditions in wind tunnels, and fitting free-flying birds with data loggers, that are either retrieved or read remotely via satellite links. The performance that comes to light depends on the known limitations of the materials from which they are made, and the conditions in which the birds live. Bird glide polars can be obtained by training birds to glide in a tilting wind tunnel. Translating these curves to power required from the flight muscles in level flight requires drag coefficients to be measured, which unfortunately does not work with bird bodies, because the flow is always fully detached. The drag of bodies in level flight can be determined by observing wingbeat frequency, and shows CD values around 0.08 in small birds, down to 0.06 in small waders specialised for efficient migration. Lift coefficients are up to 1.6 in gliding, or 1.8 for short, temporary glides. In-flight measurements can be used to calculate power curves for birds in level flight, and this has been applied to migrating geese in detail. These typically achieve lift:drag ratios around 15, including allowances for stops, as against 19 for continuous powered flight. The same calculations, applied to Pacific Black-tailed Godwits which start with fat fractions up to 0.55 at departure, show that such birds not only cross the Pacific to New Zealand, but have enough fuel in hand to reach the South Pole if that were necessary. This performance depends on the “dual fuel” arrangements of these migrants, whereby they use fat as their main fuel, and supplement this by extra fuel from burning the engine (flight muscles, as less power is needed later in the flight. The accuracy of these power curves has never been checked, although provision for stopping the bird, and making these checks at regular intervals during a simulated flight was built into the original design of the Lund wind tunnel. The

  6. Taylor dispersion of nanoparticles

    Science.gov (United States)

    Balog, Sandor; Urban, Dominic A.; Milosevic, Ana M.; Crippa, Federica; Rothen-Rutishauser, Barbara; Petri-Fink, Alke

    2017-08-01

    The ability to detect and accurately characterize particles is required by many fields of nanotechnology, including materials science, nanotoxicology, and nanomedicine. Among the most relevant physicochemical properties of nanoparticles, size and the related surface-to-volume ratio are fundamental ones. Taylor dispersion combines three independent phenomena to determine particle size: optical extinction, translational diffusion, and sheer-enhanced dispersion of nanoparticles subjected to a steady laminar flow. The interplay of these defines the apparent size. Considering that particles in fact are never truly uniform nor monodisperse, we rigorously address particle polydispersity and calculate the apparent particle size measured by Taylor dispersion analysis. We conducted case studies addressing aqueous suspensions of model particles and large-scale-produced "industrial" particles of both academic and commercial interest of various core materials and sizes, ranging from 15 to 100 nm. A comparison with particle sizes determined by transmission electron microscopy confirms that our approach is model-independent, non-parametric, and of general validity that provides an accurate account of size polydispersity—independently on the shape of the size distribution and without any assumption required a priori.

  7. Why birds with deferred sexual maturity are sedentary on islands: a systematic review.

    Directory of Open Access Journals (Sweden)

    Miguel Ferrer

    Full Text Available BACKGROUND: Island faunas have played central roles in the development of evolutionary biology and ecology. Birds are among the most studied organisms on islands, in part because of their dispersal powers linked to migration. Even so, we lack of information about differences in the movement ecology of island versus mainland populations of birds. METHODOLOGY/PRINCIPAL FINDINGS: Here we present a new general pattern indicating that large birds with deferred sexual maturity are sedentary on islands, and that they become so even when they are migratory on the mainland. Density-dependent variation in the age at first breeding affects the survivorship of insular populations and this, in turn, affects the movement ecology of large birds. Because density-dependent variation in the age of first breeding is critical to the long-term survival of small isolated populations of long-lived species, migratory forms can successfully colonize islands only if they become sedentary once there. Analyses of the movement ecology of continental and insular populations of 314 species of raptors, 113 species of Ciconiiformes and 136 species of passerines, along with individual-based population simulations confirm this prediction. CONCLUSIONS: This finding has several consequences for speciation, colonization and survival of small isolated population of species with deferred sexual maturity.

  8. Bird Pollinator Visitation is Equivalent in Island and Plantation Planting Designs in Tropical Forest Restoration Sites

    Directory of Open Access Journals (Sweden)

    Ginger M. Thurston

    2013-03-01

    Full Text Available Active restoration is one strategy to reverse tropical forest loss. Given the dynamic nature of climates, human populations, and other ecosystem components, the past practice of using historical reference sites as restoration targets is unlikely to result in self-sustaining ecosystems. Restoring sustainable ecological processes like pollination is a more feasible goal. We investigated how flower cover, planting design, and landscape forest cover influenced bird pollinator visits to Inga edulis trees in young restoration sites in Costa Rica. I. edulis trees were located in island plantings, where seedlings had been planted in patches, or in plantation plantings, where seedlings were planted to cover the restoration area. Sites were located in landscapes with scant (10–21% or moderate (35–76% forest cover. Trees with greater flower cover received more visits from pollinating birds; neither planting design nor landscape forest cover influenced the number of pollinator visits. Resident hummingbirds and a migratory bird species were the most frequent bird pollinators. Pollination in the early years following planting may not be as affected by details of restoration design as other ecological processes like seed dispersal. Future work to assess the quality of various pollinator species will be important in assessing this idea.

  9. The promotion of oral health within Health Promoting Schools in KwaZulu-Natal

    Directory of Open Access Journals (Sweden)

    M Reddy

    2017-04-01

    Full Text Available Background. Oral health promotion is a cost-effective strategy that can be implemented at schools for the prevention of oral diseases. Theimportance and value of school-based interventions in children has been identified in South Africa (SA. Although oral health strategiesinclude integrated school-based interventions, there is a lack of published evidence on whether these strategies have been translated intopractice and whether these programmes have been evaluated.Objective. To assess the efficiency and sustainability of the toothbrushing programme implemented at health-promoting schools inKwaZulu-Natal Province, SA.Methods. A mixed-methods approach was used for this study, conducted at 23 health-promoting schools in KwaZulu-Natal using focusgroup discussions. Triangulation was used for evaluation.Results. The intervention implemented had created awareness of oral health for learners, educators and parents. Findings in this studyindicate that although there were benefits obtained from this school-based intervention, many challenges, such as time constraints, largeclasses and a lack of adequate resources and funding, affected the sustainability of the programme.Conclusion.The school setting has the potential to deliver integrated preventive and promotive programmes provided they are supportedby adequate funding and resources.

  10. Predictive modelling of wetland occurrence in KwaZulu-Natal, South Africa

    Directory of Open Access Journals (Sweden)

    Jens Hiestermann

    2015-07-01

    Full Text Available The global trend of transformation and loss of wetlands through conversion to other land uses has deleterious effects on surrounding ecosystems, and there is a resultant increasing need for the conservation and preservation of wetlands. Improved mapping of wetland locations is critical to achieving objective regional conservation goals, which depends on accurate spatial knowledge. Current approaches to mapping wetlands through the classification of satellite imagery typically under-represents actual wetland area; the importance of ancillary data in improving accuracy in mapping wetlands is therefore recognised. In this study, we compared two approaches Bayesian networks and logistic regression to predict the likelihood of wetland occurrence in KwaZulu-Natal, South Africa. Both approaches were developed using the same data set of environmental surrogate predictors. We compared and verified model outputs using an independent test data set, with analyses including receiver operating characteristic curves and area under the curve (AUC. Both models performed similarly (AUC>0.84, indicating the suitability of a likelihood approach for ancillary data for wetland mapping. Results indicated that high wetland probability areas in the final model outputs correlated well with known wetland systems and wetland-rich areas in KwaZulu-Natal. We conclude that predictive models have the potential to improve the accuracy of wetland mapping in South Africa by serving as valuable ancillary data.

  11. Number One Reef: An overstepped segmented lagoon complex on the KwaZulu-Natal continental shelf

    Directory of Open Access Journals (Sweden)

    Godfrey Vella

    2012-07-01

    Full Text Available This study of the bathymetry of the mid-shelf of the Durban Bight, KwaZulu-Natal revealed a series of previously undocumented seafloor features. These features were mapped using a high-resolution multibeam bathymetric echosounder and a detailed map of the seafloor topography was produced. We recognised several features that closely resemble features of contemporary segmented lagoon and lake systems: semicircular seafloor depressions, arcuate ridges, cuspate spits and prograding submerged barriers. Based on the striking similarity in morphology to Kosi Bay – a segmented lagoon system from the sandy northern KwaZulu-Natal coastal plain – a similar evolutionary model is proposed. This model is of an incised valley formed following a sea level lowering to the Last Glacial Maximum at about 18 000 BP. Thereafter, continued transgressive infilling occurred to a point where an extensive lagoon and back-barrier system was established. At this point, sea levels remained static, causing the net segmentation of the system and the slow closure of the tidal basins or circular depressions. This type of seafloor topography is rarely preserved and is the result of fortuitous cementation after deposition and the later removal of sediment that would ordinarily bury such features.

  12. Natality and calf mortality of the Northern Alaska Peninsula and Southern Alaska Peninsula caribou herds

    Directory of Open Access Journals (Sweden)

    Richard A. Sellers

    2003-04-01

    Full Text Available We studied natality in the Northern Alaska Peninsula (NAP and Southern Alaska Peninsula (SAP caribou (Rangifer tarandus granti herds during 1996-1999, and mortality and weights of calves during 1998 and 1999- Natality was lower in the NAP than the SAP primarily because most 3-year-old females did not produce calves in the NAP Patterns of calf mortality in the NAP and SAP differed from those in Interior Alaska primarily because neonatal (i.e., during the first 2 weeks of life mortality was relatively low, but mortality continued to be significant through August in both herds, and aggregate annual mortality was extreme (86% in the NAP Predators probably killed more neonatal calves in the SAP, primarily because a wolf den (Canis lupus was located on the calving area. Despite the relatively high density of brown bears (Ursus arctos and bald eagles (Haliaeetus leucocephalus, these predators killed surprisingly few calves. Golden eagles (Aquila chrysaetos were uncommon on the Alaska Peninsula. At least 2 calves apparently died from pneu¬monia in the range of the NAP but none were suspected to have died from disease in the range of the SAP. Heavy scav¬enging by bald eagles complicated determining cause of death of calves in both the NAP and SAP.

  13. Sex determination using humeral dimensions in a sample from KwaZulu-Natal: an osteometric study.

    Science.gov (United States)

    Ogedengbe, Oluwatosin Olalekan; Ajayi, Sunday Adelaja; Komolafe, Omobola Aderibigbe; Zaw, Aung Khaing; Naidu, Edwin Coleridge Stephen; Okpara Azu, Onyemaechi

    2017-09-01

    The morphological characteristics of the humeral bone has been investigated in recent times with studies showing varying degrees of sexual dimorphism. Osteologists and forensic scientists have shown that sex determination methods based on skeletal measurements are population specific, and these population-specific variations are present in many body dimensions. The present study aims to establish sex identification using osteometric standards for the humerus in a contemporary KwaZulu-Natal population. A total of 11 parameters were measured in a sample of n=211 humeri (males, 113; females, 98) from the osteological collection in the Discipline of Clinical Anatomy, Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa. The difference in means for nearly all variables were found to be significantly higher in males compared to females ( P <0.01) with the most effective single parameter for predicting sex being the vertical head diameter having an accuracy of 82.5%. Stepwise discriminant analysis increased the overall accuracy rate to 87.7% when all measurements were jointly applied. We conclude that the humerus is an important bone which can be reliably used for sex determination based on standard metric methods despite minor tribal or ancestral differences amongst an otherwise homogenous population.

  14. The contribution of public capital towards economic growth: A KwaZulu-Natal case study

    Directory of Open Access Journals (Sweden)

    Clive E. Coetzee

    2017-04-01

    Aim: The way provincial or regional growth depends on infrastructure is investigated in this article and it is applied to data from KwaZulu-Natal province, as an illustration. Setting: This study investigates the extent to which infrastructure in KwaZulu-Natal province in South Africa leads towards economic growth of the province. Methods: From a theoretical framework, this article develops an endogenous growth model, which investigates the association between provincial public capital stock expenditure and economic growth. Data series for public capital formation are first developed to apply in this study and others to follow. Econometric techniques are then employed, using quarterly data between 2001 and 2015, to assess the set hypothesis that growth in expenditure on public capital leads to national economic growth. Results: The empirical results support the argument of a positive relationship between provincial capital stock and economic growth in the long-term. The findings also suggests that the long-term causality or effect fades over time, albeit slowly. Conclusion: The nature and statistical significance of the long-term equilibrium relationship seems to be ambiguous at best. Some evidence of an equilibrium relationship in the short-term was, however, also observed. In conclusion, there also seems to be some causality between provincial capital stock and provincial gross domestic product in the short-run.

  15. KEANEKARAGAMAN JENIS IKAN DI SUNGAI BATANG GADIS MANDAILING NATAL SUMATERA UTARA

    Directory of Open Access Journals (Sweden)

    Yusni Atifah

    2017-12-01

    Full Text Available Batang Gadis River, located in Mandailing Natal, faces a severe threat by the increase of human activities along the river. The fish community, as well as other biotas, is exposed to reducing environmental condition. Therefore, the study of fish community in this river is essential to get the most recent condition as a baseline data. The purpose of this research was to determine the species diversity of fish in Batang Gadis River of Mandailing Natal. This research used a descriptive exploratory method by surveying with purposive sampling method to collect samples at four specified stations. This study used a fishing net with a zig-zag pattern of sampling covered the river bank for about 200–300m at each observation station. The collected fish samples were identified at the Biology Laboratory of the University of Muhammadiyah Tapanuli Selatan. This study found ten species of fish from five families. The family with the most significant members was Cyprinidae (6 species, and the other families, Bagridae, Clariidae, Nemachelidae, and Loricariidae, were found with only one species. The species diversity comprised of Rasbora lateristriata, Nemacheilus fasciatus, Mystacoleucus marginatus, Tor tambra, Cyprinus carpio, Clarias bathracus, Rasbora argyrotaenia , Barbonymus gonionotus, Puntius binotatus, Bagrus nemurus, and Pterygoplichthys pardalis. The fish population of Batang Gadis River has diversity index (H’ of 1.77 and similarity index (E of 0.77.

  16. Comparative analysis of vestibular ecomorphology in birds.

    Science.gov (United States)

    Benson, Roger B J; Starmer-Jones, Ethan; Close, Roger A; Walsh, Stig A

    2017-12-01

    The bony labyrinth of vertebrates houses the semicircular canals. These sense rotational accelerations of the head and play an essential role in gaze stabilisation during locomotion. The sizes and shapes of the semicircular canals have hypothesised relationships to agility and locomotory modes in many groups, including birds, and a burgeoning palaeontological literature seeks to make ecological interpretations from the morphology of the labyrinth in extinct species. Rigorous tests of form-function relationships for the vestibular system are required to support these interpretations. We test the hypothesis that the lengths, streamlines and angles between the semicircular canals are related to body size, wing kinematics and flying style in birds. To do this, we applied geometric morphometrics and multivariate phylogenetic comparative methods to a dataset of 64 three-dimensional reconstructions of the endosseous labyrinth obtained using micro-computed tomography scanning of bird crania. A strong relationship between centroid size of the semicircular canals and body size indicates that larger birds have longer semicircular canals compared with their evolutionary relatives. Wing kinematics related to manoeuvrability (and quantified using the brachial index) explain a small additional portion of the variance in labyrinth size. We also find strong evidence for allometric shape change in the semicircular canals of birds, indicating that major aspects of the shape of the avian labyrinth are determined by spatial constraints. The avian braincase accommodates a large brain, a large eye and large semicircular canals compared with other tetrapods. Negative allometry of these structures means that the restriction of space within the braincase is intense in small birds. This may explain our observation that the angles between planes of the semicircular canals of birds deviate more strongly from orthogonality than those of mammals, and especially from agile, gliding and flying

  17. Natal teeth

    Science.gov (United States)

    ... that influence the process. In: Dean JA, ed. McDonald and Avery's Dentistry for the Child and Adolescent . ... M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health ...

  18. Native fruit traits may mediate dispersal competition between native and non-native plants

    Directory of Open Access Journals (Sweden)

    Clare Aslan

    2012-02-01

    Full Text Available Seed disperser preferences may mediate the impact of invasive, non-native plant species on their new ecological communities. Significant seed disperser preference for invasives over native species could facilitate the spread of the invasives while impeding native plant dispersal. Such competition for dispersers could negatively impact the fitness of some native plants. Here, we review published literature to identify circumstances under which preference for non-native fruits occurs. The importance of fruit attraction is underscored by several studies demonstrating that invasive, fleshy-fruited plant species are particularly attractive to regional frugivores. A small set of studies directly compare frugivore preference for native vs. invasive species, and we find that different designs and goals within such studies frequently yield contrasting results. When similar native and non-native plant species have been compared, frugivores have tended to show preference for the non-natives. This preference appears to stem from enhanced feeding efficiency or accessibility associated with the non-native fruits. On the other hand, studies examining preference within existing suites of co-occurring species, with no attempt to maximize fruit similarity, show mixed results, with frugivores in most cases acting opportunistically or preferring native species. A simple, exploratory meta-analysis finds significant preference for native species when these studies are examined as a group. We illustrate the contrasting findings typical of these two approaches with results from two small-scale aviary experiments we conducted to determine preference by frugivorous bird species in northern California. In these case studies, native birds preferred the native fruit species as long as it was dissimilar from non-native fruits, while non-native European starlings preferred non-native fruit. However, native birds showed slight, non-significant preference for non-native fruit

  19. Timing of initial arrival at the breeding site predicts age at first reproduction in a long-lived migratory bird

    Science.gov (United States)

    Becker, Peter H.; Dittmann, Tobias; Ludwigs, Jan-Dieter; Limmer, Bente; Ludwig, Sonja C.; Bauch, Christina; Braasch, Alexander; Wendeln, Helmut

    2008-01-01

    In long-lived vertebrates, individuals generally visit potential breeding areas or populations during one or more seasons before reproducing for the first time. During these years of prospecting, they select a future breeding site, colony, or mate and improve various skills and their physical condition to meet the requirements of reproduction. One precondition of successful reproduction is arrival in time on the breeding grounds. Here, we study the intricate links among the date of initial spring arrival, body mass, sex, and the age of first breeding in the common tern Sterna hirundo, a long-lived migratory colonial seabird. The study is based on a unique, individual-based, long-term dataset of sexed birds, marked with transponders, which allow recording their individual arrival, overall attendance, and clutch initiation remotely and automatically year by year over the entire lifetime at the natal colony site. We show that the seasonal date of initial arrival at the breeding grounds predicts the individual age at first reproduction, which mostly occurs years later. Late first-time arrivals remain delayed birds throughout subsequent years. Our findings reveal that timing of arrival at the site of reproduction and timing of reproduction itself are coherent parameters of individual quality, which are linked with the prospects of the breeding career and may have consequences for fitness. PMID:18711134

  20. Nozzle for electric dispersion reactor

    Science.gov (United States)

    Sisson, W.G.; Basaran, O.A.; Harris, M.T.

    1995-11-07

    A nozzle for an electric dispersion reactor includes two concentric electrodes, the inner one of the two delivering disperse phase fluid into a continuous phase fluid. A potential difference generated by a voltage source creates a dispersing electric field at the end of the inner electrode. 4 figs.

  1. 76 FR 44729 - Migratory Bird Hunting; Proposed Frameworks for Early-Season Migratory Bird Hunting Regulations...

    Science.gov (United States)

    2011-07-26

    ...- 2010 average (3.4 0.03 million). As expected, residual water from summer 2010 precipitation remained in... preliminary 2010 Migratory Bird Harvest Information Program (HIP) estimate of harvest was 84,900 birds. In... trend in the population indices between 1966 and 2010. According to HIP surveys, the preliminary harvest...

  2. 75 FR 47681 - Migratory Bird Hunting; Proposed Migratory Bird Hunting Regulations on Certain Federal Indian...

    Science.gov (United States)

    2010-08-06

    ... million). Residual water remains in the Parklands and these were classified as fair to good. Most of the... stabilized at around 100,000 birds; the preliminary 2009 Migratory Bird Harvest Information Program (HIP... and 2009. According to HIP surveys, the preliminary harvest estimate for 2009 was 66,100 white-winged...

  3. 78 FR 75321 - Migratory Bird Subsistence Harvest in Alaska; Harvest Regulations for Migratory Birds in Alaska...

    Science.gov (United States)

    2013-12-11

    ... the taking of migratory birds and the collection of their eggs, by the indigenous inhabitants of the... particular land ownership, but applies to the harvesting of migratory bird resources throughout Alaska. A... ensure an effective and meaningful role for Alaska's indigenous inhabitants in the conservation of...

  4. 77 FR 58443 - Migratory Bird Hunting; Final Frameworks for Late-Season Migratory Bird Hunting Regulations

    Science.gov (United States)

    2012-09-20

    ... to move toward a more holistic and uniform approach to Canada goose harvest management across the... selections to: Chief, Division of Migratory Bird Management, U.S. Fish and Wildlife Service, ms MBSP-4107... address above, or from the Division of Migratory Bird Management's Web site at http://www.fws.gov...

  5. GEOMETRICAL PARAMETERS OF EGGS IN BIRD SYSTEMATICS

    Directory of Open Access Journals (Sweden)

    I. S. Mityay

    2014-12-01

    Full Text Available Our ideas are based on the following assumptions. Egg as a standalone system is formed within another system, which is the body of the female. Both systems are implemented on the basis of a common genetic code. In this regard, for example, the dendrogram constructed by morphological criteria eggs should be approximately equal to those constructed by other molecular or morphological criteria adult birds. It should be noted that the dendrogram show only the degree of genetic similarity of taxa, therefore, the identity of materials depends on the number of analyzed criteria and their quality, ie, they should be the backbone. The greater the number of system-features will be included in the analysis and in one other case, the like are dendrogram. In other cases, we will have a fragmentary similarity, which is also very important when dealing with controversial issues. The main message of our research was to figure out the eligibility of usage the morphological characteristics of eggs as additional information in taxonomy and phylogeny of birds. Our studies show that the shape parameters of bird eggs show a stable attachment to certain types of birds and complex traits are species-specific. Dendrogram and diagrams built by the quantitative value of these signs, exhibit significant similarity with the dendrogram constructed by morphological, comparative anatomy, paleontology and molecular criteria for adult birds. This suggests the possibility of using morphological parameters eggs as additional information in dealing with taxonomy and phylogeny of birds. Keywords: oology, geometrical parameters of eggs, bird systematics

  6. The Strength and Drivers of Bird-Mediated Selection on Fruit Crop Size: A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Facundo X. Palacio

    2018-02-01

    Full Text Available In seed-dispersal mutualisms, the number of fruit a plant displays is a key trait, as it acts as a signal for seed dispersers that entails fruit removal and exportation of reproductive units (fruit crop size hypothesis. Although this hypothesis has gained general acceptance, forces driving the shape and strength of natural selection exerted by birds on fruit crop size remains an unresolved matter. Here, we propose that ecological filters promoting high functional equivalence of interacting partners (similar functional roles translate into similar selection pressures on fruit crop size, enhancing selection strength on this trait. We performed a meta-analysis on 50 seed-dispersal systems to test the hypothesis that frugivorous birds exert positive selection pressure on fruit crop size, and to assess whether different factors expected to act as filters (fruit diameter, fruit type, fruiting season length, bird functional groups, and latitude influence phenotypic selection regimes on this trait. Birds promote larger fruit crop sizes as a general pattern in nature. Short fruiting seasons and a high proportion of species belonging to the same functional group showed higher selection strength on fruit crop size. Also, selection strength on fruit crop size increased for large-fruited species and toward the tropics. Our results support the hypothesis that fruit crop size represents a conspicuous signal advertising the amount of reward to visually driven interacting partners, and that both plant and bird traits, as well as environmental factors, drive selection strength on fruit display traits. Furthermore, our results suggest that the relationship among forces impinged by phenology and frugivore functional roles may be key to understand their evolutionary stability.

  7. Exploration potential of Paraiba and Natal platform basins, NE Brazil; Potencial exploratorio das bacias da Paraiba e da plataforma de Natal, NE do Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Jose A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Lima Filho, Mario; Neumann, Virginio H. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Geologia; Maranhao Neto, Jose Carneiro; Araujo, Joao A.A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Programa de Pos Graduacao em Geociencias

    2008-07-01

    The portion of Brazilian continental margin located between the Pernambuco Shear Zone (ZCPE) and Touros High, enclosing Natal Platform and Paraiba basin, NE Brazil, presents a thin sedimentary cover represented by Neo- Cretaceous deposits, over an elevated basement. In this zone the narrow platform ends abruptly against the ocean plate, forming a scarped slope. This area corresponds to the Transverse zone of Northeast Brazil (TZN) limited by two extensive transcurrent E-W shear zones that acted as accommodation zones for the strain produced by the advance of the southern and northern rift branches. During the Aptian, the rift suffered a NE deflection and contoured the Borborema Province and the TZN. The resistance of this block to the rift advance generated a prominent and elevated region into the Atlantic gulf which resulted in the absence of rift deposition over the Brazilian margin and its deviation to the African side. The model suggested by this paper denominates this area as the 'exception zone' of the Brazilian margin, which possess a poor petroliferous potential and need to be separated from the sector corresponding to the Pernambuco basin, located to south of ZCPE, representing the last piece of margin before the rift deflection and possessing an important petroliferous potential. (author)

  8. Functional morphology and seed anatomy of the invasive weed, benghal dayflower (Commelina benghalensis): Implications for dispersal by mourning doves

    Science.gov (United States)

    Benghal dayflower (BD) is an exotic weed that reduces yields in many agricultural crops. Potential dispersal of this weed by migratory Mourning doves was investigated in this study. Evidence shows that doves feed on BD seeds, with some birds containing hundreds of seeds. Seeds extracted from harvest...

  9. Tracer dispersion - experiment and CFD

    International Nuclear Information System (INIS)

    Zitny, R.

    2004-01-01

    Description of tracer distribution by means of dispersion models is a method successfully used in process engineering for fifty years. Application of dispersion models in reactor engineering for characterization of flows in column apparatus, heat exchangers, etc. is summarized and experimental tracer techniques as well as CFD methods for dispersion coefficients evaluation are discussed. Possible extensions of thermal axial dispersion model (ADM) and a core-wall ADM model suitable for description of tracer dispersion in laminar flows are suggested as well as CFD implementation as 1D finite elements. (author)

  10. High density dispersion fuel

    International Nuclear Information System (INIS)

    Hofman, G.L.

    1996-01-01

    A fuel development campaign that results in an aluminum plate-type fuel of unlimited LEU burnup capability with an uranium loading of 9 grams per cm 3 of meat should be considered an unqualified success. The current worldwide approved and accepted highest loading is 4.8 g cm -3 with U 3 Si 2 as fuel. High-density uranium compounds offer no real density advantage over U 3 Si 2 and have less desirable fabrication and performance characteristics as well. Of the higher-density compounds, U 3 Si has approximately a 30% higher uranium density but the density of the U 6 X compounds would yield the factor 1.5 needed to achieve 9 g cm -3 uranium loading. Unfortunately, irradiation tests proved these peritectic compounds have poor swelling behavior. It is for this reason that the authors are turning to uranium alloys. The reason pure uranium was not seriously considered as a dispersion fuel is mainly due to its high rate of growth and swelling at low temperatures. This problem was solved at least for relatively low burnup application in non-dispersion fuel elements with small additions of Si, Fe, and Al. This so called adjusted uranium has nearly the same density as pure α-uranium and it seems prudent to reconsider this alloy as a dispersant. Further modifications of uranium metal to achieve higher burnup swelling stability involve stabilization of the cubic γ phase at low temperatures where normally α phase exists. Several low neutron capture cross section elements such as Zr, Nb, Ti and Mo accomplish this in various degrees. The challenge is to produce a suitable form of fuel powder and develop a plate fabrication procedure, as well as obtain high burnup capability through irradiation testing

  11. Comparing aerodynamic efficiency in birds and bats suggests better flight performance in birds.

    Science.gov (United States)

    Muijres, Florian T; Johansson, L Christoffer; Bowlin, Melissa S; Winter, York; Hedenström, Anders

    2012-01-01

    Flight is one of the energetically most costly activities in the animal kingdom, suggesting that natural selection should work to optimize flight performance. The similar size and flight speed of birds and bats may therefore suggest convergent aerodynamic performance; alternatively, flight performance could be restricted by phylogenetic constraints. We test which of these scenarios fit to two measures of aerodynamic flight efficiency in two passerine bird species and two New World leaf-nosed bat species. Using time-resolved particle image velocimetry measurements of the wake of the animals flying in a wind tunnel, we derived the span efficiency, a metric for the efficiency of generating lift, and the lift-to-drag ratio, a metric for mechanical energetic flight efficiency. We show that the birds significantly outperform the bats in both metrics, which we ascribe to variation in aerodynamic function of body and wing upstroke: Bird bodies generated relatively more lift than bat bodies, resulting in a more uniform spanwise lift distribution and higher span efficiency. A likely explanation would be that the bat ears and nose leaf, associated with echolocation, disturb the flow over the body. During the upstroke, the birds retract their wings to make them aerodynamically inactive, while the membranous bat wings generate thrust and negative lift. Despite the differences in performance, the wake morphology of both birds and bats resemble the optimal wake for their respective lift-to-drag ratio regimes. This suggests that evolution has optimized performance relative to the respective conditions of birds and bats, but that maximum performance is possibly limited by phylogenetic constraints. Although ecological differences between birds and bats are subjected to many conspiring variables, the different aerodynamic flight efficiency for the bird and bat species studied here may help explain why birds typically fly faster, migrate more frequently and migrate longer distances

  12. Comparing aerodynamic efficiency in birds and bats suggests better flight performance in birds.

    Directory of Open Access Journals (Sweden)

    Florian T Muijres

    Full Text Available Flight is one of the energetically most costly activities in the animal kingdom, suggesting that natural selection should work to optimize flight performance. The similar size and flight speed of birds and bats may therefore suggest convergent aerodynamic performance; alternatively, flight performance could be restricted by phylogenetic constraints. We test which of these scenarios fit to two measures of aerodynamic flight efficiency in two passerine bird species and two New World leaf-nosed bat species. Using time-resolved particle image velocimetry measurements of the wake of the animals flying in a wind tunnel, we derived the span efficiency, a metric for the efficiency of generating lift, and the lift-to-drag ratio, a metric for mechanical energetic flight efficiency. We show that the birds significantly outperform the bats in both metrics, which we ascribe to variation in aerodynamic function of body and wing upstroke: Bird bodies generated relatively more lift than bat bodies, resulting in a more uniform spanwise lift distribution and higher span efficiency. A likely explanation would be that the bat ears and nose leaf, associated with echolocation, disturb the flow over the body. During the upstroke, the birds retract their wings to make them aerodynamically inactive, while the membranous bat wings generate thrust and negative lift. Despite the differences in performance, the wake morphology of both birds and bats resemble the optimal wake for their respective lift-to-drag ratio regimes. This suggests that evolution has optimized performance relative to the respective conditions of birds and bats, but that maximum performance is possibly limited by phylogenetic constraints. Although ecological differences between birds and bats are subjected to many conspiring variables, the different aerodynamic flight efficiency for the bird and bat species studied here may help explain why birds typically fly faster, migrate more frequently and migrate

  13. Analýza stabilních izotopů – alternativní metoda studia migrace ptáků

    Czech Academy of Sciences Publication Activity Database

    Procházka, Petr

    2006-01-01

    Roč. 42, - (2006), s. 3-21 ISSN 0231-7796 R&D Projects: GA AV ČR KJB600930508 Institutional research plan: CEZ:AV0Z60930519 Keywords : bird migration * dispersal * moult patterns * movements * natal origin * stable isotop Subject RIV: EG - Zoology http://www. bird life.cz/wpimages/other/sylvia42-1Prochazka.pdf

  14. Osedax borings in fossil marine bird bones

    Science.gov (United States)

    Kiel, Steffen; Kahl, Wolf-Achim; Goedert, James L.

    2011-01-01

    The bone-eating marine annelid Osedax consumes mainly whale bones on the deep-sea floor, but recent colonization experiments with cow bones and molecular age estimates suggesting a possible Cretaceous origin of Osedax indicate that this worm might be able grow on a wider range of substrates. The suggested Cretaceous origin was thought to imply that Osedax could colonize marine reptile or fish bones, but there is currently no evidence that Osedax consumes bones other than those of mammals. We provide the first evidence that Osedax was, and most likely still is, able to consume non-mammalian bones, namely bird bones. Borings resembling those produced by living Osedax were found in bones of early Oligocene marine flightless diving birds (family Plotopteridae). The species that produced these boreholes had a branching filiform root that grew to a length of at least 3 mm, and lived in densities of up to 40 individuals per square centimeter. The inclusion of bird bones into the diet of Osedax has interesting implications for the recent suggestion of a Cretaceous origin of this worm because marine birds have existed continuously since the Cretaceous. Bird bones could have enabled this worm to survive times in the Earth's history when large marine vertebrates other than fish were rare, specifically after the disappearance of large marine reptiles at the end-Cretaceous mass extinction event and before the rise of whales in the Eocene.

  15. Birds of Sierra de Vallejo, Nayarit, Mexico

    Directory of Open Access Journals (Sweden)

    Figueroa-Esquivel, E.M.

    2014-01-01

    Full Text Available Sierra de Vallejo, is considered a priority region for conservation, and is strongly affected by anthropogenic pressures. The inventory of birds are refers to studies in near areas. This study is a concrete contribution of the birds of the mountain chain and north of it. We considered bibliographic records and databases available on the web with records of ocurrence and specimens of scientific collections. Also we perform point counts in different localities inside the reserve. We observed a richness of 261 birds species, the family Tyrannidae is the best represented. Of the species recorded, 177 are permanent residents (31 are endemic and 15 are quasi-endemics to Mexico and 73 are migratory; the remaining eleven records have other status. Also 43 species are in endangered categories. We include species that have not been recorded in the lists of the area and records of species expand their ranges at Nayarit. Due to the great diversity of birds observed, it is necesary to continue the research work about habitat use, abundance and monitoring, it will provides the basis for the conservation of birds of Sierra de Vallejo.

  16. Spurious dispersion effects at FLASH

    International Nuclear Information System (INIS)

    Prat, Eduard

    2009-07-01

    The performance of the Free-Electron Laser (FEL) process imposes stringent demands on the transverse trajectory and size of the electron beam. Since transverse dispersion changes off-energy particle trajectories and increases the effective beam size, dispersion must be controlled. This thesis treats the concept of dispersion in linacs, and analyses the impact of dispersion on the electron beam and on the FEL process. It presents generation mechanisms for spurious dispersion, quantifying its importance for FLASH (Free-electron Laser in Hamburg) and the XFEL (European X-ray Free-Electron Laser). A method for measuring and correcting dispersion and its implementation in FLASH is described. Experiments of dispersion e ects on the transverse beam quality and on the FEL performance are presented. (orig.)

  17. Spurious dispersion effects at FLASH

    Energy Technology Data Exchange (ETDEWEB)

    Prat, Eduard

    2009-07-15

    The performance of the Free-Electron Laser (FEL) process imposes stringent demands on the transverse trajectory and size of the electron beam. Since transverse dispersion changes off-energy particle trajectories and increases the effective beam size, dispersion must be controlled. This thesis treats the concept of dispersion in linacs, and analyses the impact of dispersion on the electron beam and on the FEL process. It presents generation mechanisms for spurious dispersion, quantifying its importance for FLASH (Free-electron Laser in Hamburg) and the XFEL (European X-ray Free-Electron Laser). A method for measuring and correcting dispersion and its implementation in FLASH is described. Experiments of dispersion e ects on the transverse beam quality and on the FEL performance are presented. (orig.)

  18. Dispersion stability of thermal nanofluids

    Directory of Open Access Journals (Sweden)

    Fan Yu

    2017-10-01

    Full Text Available Thermal nanofluids, the engineered fluids with dispersed functional nanoparticles, have exhibited extraordinary thermophysical properties and added functionalities, and thus have enabled a broad range of important applications. The poor dispersion stability of thermal nanofluids, however, has been considered as a long-existing issue that limits their further development and practical application. This review overviews the recent efforts and progresses in improving the dispersion stability of thermal nanofluids such as mechanistic understanding of dispersion behavior of nanofluids, examples of both water-based and oil-based nanofluids, strategies to stabilize nanofluids, and characterization techniques for dispersion behavior of nanofluids. Finally, on-going research needs, and possible solutions to research challenges and future research directions in exploring stably dispersed thermal nanofluids are discussed. Keywords: Thermal nanofluids, Dispersion, Aggregation, Electrostatic stabilization, Steric stabilization

  19. Potential spread of highly pathogenic avian influenza H5N1 by wildfowl: dispersal ranges and rates determined from large-scale satellite telemetry

    Science.gov (United States)

    Gaidet, Nicolas; Cappelle, Julien; Takekawa, John Y.; Prosser, Diann J.; Iverson, Samuel A.; Douglas, David C.; Perry, William M.; Mundkur, Taej; Newman, Scott H.

    2010-01-01

    1. Migratory birds are major candidates for long-distance dispersal of zoonotic pathogens. In recent years, wildfowl have been suspected of contributing to the rapid geographic spread of the highly pathogenic avian influenza (HPAI) H5N1 virus. Experimental infection studies reveal that some wild ducks, geese and swans shed this virus asymptomatically and hence have the potential to spread it as they move. 2. We evaluate the dispersive potential of HPAI H5N1 viruses by wildfowl through an analysis of the movement range and movement rate of birds monitored by satellite telemetry in relation to the apparent asymptomatic infection duration (AID) measured in experimental studies. We analysed the first large-scale data set of wildfowl movements, including 228 birds from 19 species monitored by satellite telemetry in 2006–2009, over HPAI H5N1 affected regions of Asia, Europe and Africa. 3. Our results indicate that individual migratory wildfowl have the potential to disperse HPAI H5N1 over extensive distances, being able to perform movements of up to 2900 km within timeframes compatible with the duration of asymptomatic infection. 4. However, the likelihood of such virus dispersal over long distances by individual wildfowl is low: we estimate that for an individual migratory bird there are, on average, only 5–15 days per year when infection could result in the dispersal of HPAI H5N1 virus over 500 km. 5. Staging at stopover sites during migration is typically longer than the period of infection and viral shedding, preventing birds from dispersing a virus over several consecutive but interrupted long-distance movements. Intercontinental virus dispersion would therefore probably require relay transmission between a series of successively infected migratory birds. 6. Synthesis and applications. Our results provide a detailed quantitative assessment of the dispersive potential of HPAI H5N1 virus by selected migratory birds. Such dispersive potential rests on the

  20. A literature review of tele-dermatology programs in the South African public health sector: Kwazulu-Natal perspective

    CSIR Research Space (South Africa)

    Walters, Laticha EM

    2015-11-01

    Full Text Available South Africa’s HIV/AIDS prevalence rate is 17,9%, the highest being in KwaZulu-Natal. Dermatological diseases are linked to HIV/AIDS. Tele-dermatology was not part of the 1998 National Telemedicine Project. Only phase I (of three) was implemented...

  1. Climate controls on late Pleistocene landscape evolution of the Okhombe valley, KwaZulu-Natal, South Africa

    NARCIS (Netherlands)

    Temme, A.J.A.M.; Baartman, J.E.M.; Botha, G.A.; Veldkamp, A.; Jongmans, A.G.; Wallinga, J.

    2008-01-01

    Hillslopes in central and western parts of KwaZulu-Natal, South Africa are often mantled by colluvial sediments of the Masotcheni Formation. These sediments have accreted in response to several cycles of deposition, pedogenesis and incomplete erosion. Climatic controls on these cycles are

  2. Dynamics of some forests in Kwa Zulu-Natal, South Africa, based on ordinations and size-class distributions

    CSIR Research Space (South Africa)

    Everard, DA

    1995-12-01

    Full Text Available Indigenous forest in Kwa Zulu-Natal has been fairly well described, however, very little has been published on its dynamics. There is, to our knowledge, nothing published on disturbances regimes, dendrology and life histories of constituent species...

  3. Building a Future without Gender Violence: Rural Teachers and Youth in Rural Kwazulu-Natal, South Africa, Leading Community Dialogue

    Science.gov (United States)

    de Lange, Naydene; Mitchell, Claudia

    2014-01-01

    This article advances the idea that rural youth and teachers are the key in leading community dialogue towards addressing gender-based violence (GBV) in their community through their film making. The youth voices on the realities of GBV in their school and community, in rural KwaZulu-Natal, South Africa, captured through the process of…

  4. Innovative look at dairy heifer rearing: Effect of prenatal and post-natal environment on later performance.

    Science.gov (United States)

    Van Eetvelde, M; Opsomer, G

    2017-08-01

    As heifer rearing is a costly investment, dairy farmers have been stimulated to maximize early growth of their calves, mainly by enhanced liquid feeding. However, the long-term effects of this "accelerated growth" are largely unknown. Studies recently performed at Ghent University indicate that in dairy cattle, certain maternal factors (such as young age and high milk yield) and environmental factors (such as high ambient temperatures) create a suboptimal environment for the developing foetus, altering the phenotype of the newborn calf. According to the "thrifty phenotype hypothesis," these metabolic alterations prepare the newborn for similar ("matching") conditions after birth, enhancing its survival during periods of limited feeding. Yet, when an abundance of nutrients is available in post-natal life (e.g., during periods of enhanced feeding), the "mismatch" between pre- and post-natal environment results in an early catch-up growth, with potential negative consequences. The aim of the article was to discuss this mismatch between pre- and post-natal environment in dairy calves. Previous studies, especially in human medicine, have shown catch-up growth to be associated with obesity, fertility problems, metabolic diseases and a reduced lifespan. Hence, we hypothesize that, by applying programs of accelerated growth, our current management system accentuates the mismatch between the pre- and post-natal environment in dairy calves. We can conclude that, although more research is necessary, the current findings point towards a more individual approach when rearing dairy heifers. © 2017 Blackwell Verlag GmbH.

  5. IVF culture medium affects post-natal weight in humans during the first 2 years of life

    NARCIS (Netherlands)

    Kleijkers, Sander H. M.; van Montfoort, Aafke P. A.; Smits, Luc J. M.; Viechtbauer, Wolfgang; Roseboom, Tessa J.; Nelissen, Ewka C. M.; Coonen, Edith; Derhaag, Josien G.; Bastings, Lobke; Schreurs, Inge E. L.; Evers, Johannes L. H.; Dumoulin, John C. M.

    2014-01-01

    Is post-natal growth during the first 2 years of life in IVF singletons affected by type of medium used for culturing human embryos during an IVF treatment? The in vitro culture of human embryos in medium from Cook resulted in singletons with a lower weight during the first 2 years of life compared

  6. Creating a commodified wilderness: Tourism, private game farming, and 'third nature' landscapes in KwaZulu-Natal

    NARCIS (Netherlands)

    Brooks, S.; Spierenburg, M.J.; Brakel, L.; Kolk, A.; Lukhozi, K.B.

    2011-01-01

    This article explores contemporary cultural geographies and underlying histories of change on private land in post-apartheid South Africa. Its focus is the expansion of wildlife-based tourism and related forms of commodified wilderness consumption in KwaZulu-Natal province. The article explores the

  7. Estimating the cost of the mass treatment campaign for schistosomiasis in Ugu District, KwaZulu-Natal, 2012

    DEFF Research Database (Denmark)

    Maphumulo, Andile A; Gagai, Silindile; Lothe, Andrea

    2013-01-01

    , from a provider perspective. Costs were classified by cost inputs and activity. Financial records were reviewed for all 60 randomly selected schools participating in the MTC in Ugu District, KwaZulu-Natal. An Excel database was used for data analysis. Preliminary Findings: Forty five percent (16 239...

  8. Regional flood frequency analysis in the KwaZulu-Natal province, South Africa, using the index-flood method

    DEFF Research Database (Denmark)

    Kjeldsen, Thomas Rødding; Smithers, J.C.; Schulze, R.E.

    2002-01-01

    A regional frequency analysis of annual maximum series (AMS) of flood flows from relatively unregulated rivers in the KwaZulu-Natal province of South Africa has been conducted, including identification of homogeneous regions and suitable regional frequency distributions for the regions. The study...

  9. Rate and Time Trend of Perinatal, Infant, Maternal Mortality, Natality and Natural Population Growth in Kosovo

    Science.gov (United States)

    Azemi, Mehmedali; Gashi, Sanije; Berisha, Majlinda; Kolgeci, Selim; Ismaili-Jaha, Vlora

    2012-01-01

    Aim: The aim of work has been the presentation of the rate and time trends of some indicators of the heath condition of mothers and children in Kosovo: fetal mortality, early neonatal mortality, perinatal mortality, infant mortality, natality, natural growth of population etc. The treated patients were the newborn and infants in the post neonatal period, women during their pregnancy and those 42 days before and after the delivery. Methods: The data were taken from: register of the patients treated in the Pediatric Clinic of Prishtina, World Health Organization, Mother and Child Health Care, Reproductive Health Care, Ministry of Health of the Republic of Kosovo, Statistical Department of Kosovo, the National Institute of Public Health and several academic texts in the field of pediatrics. Some indicators were analyzed in a period between year 1945-2010 and 1950-2010, whereas some others were analyzed in a time period between year 2000 and 2011. Results: The perinatal mortality rate in 2000 was 29.1‰, whereas in 2011 it was 18.7‰. The fetal mortality rate was 14.5‰ during the year 2000, whereas in 2011 it was 11.0‰, in 2000 the early neonatal mortality was 14.8‰, in 2011 it was 7.5‰. The infant mortality in Kosovo was 164‰ in 1950, whereas in 2010 it was 20.5‰. The most frequent causes of infant mortality have been: lower respiratory tract infections, acute infective diarrhea, perinatal causes, congenital malformations and unclassified conditions. Maternal death rate varied during this time period. Maternal death in 2000 was 23 whereas in 2010 only two cases were reported. Regarding the natality, in 1950 it reached 46.1 ‰, whereas in 2010 it reached 14‰, natural growth of population rate in Kosovo was 29.1‰ in 1950, whereas in 2011 it was 11.0‰. Conclusion: Perinatal mortality rate in Kosovo is still high in comparison with other European countries (Turkey and Kyrgyzstan have the highest perinatal mortality rate), even though it is in a

  10. Risk factors associated with nonvaccination rabies status of dogs in KwaZulu-Natal, South Africa

    Directory of Open Access Journals (Sweden)

    Hergert M

    2016-06-01

    Full Text Available Melinda Hergert,1 Kevin le Roux,2 Louis H Nel3,4 1Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria, 2KwaZulu-Natal Department of Environment, Agriculture and Rural Development, Government Veterinary Services, Pietermaritzburg, 3Department of Microbiology and Plant Pathology, Faculty of Natural and Agricultural Sciences, University of Pretoria, Pretoria, South Africa; 4Global Alliance for Rabies Control, Manhattan, KS, USA Abstract: Canine rabies has been enzootic in the dog population of the KwaZulu-Natal ­province of South Africa since the mid-1970s and has been associated with high rates of human exposures and frequent transmissions to other domestic animal species. Several decades of control efforts, consisting primarily of mass vaccination programs, failed to sufficiently curb rabies in this province. For meaningful progression toward better control and elimination, the factors contributing to the persistence of this disease need to be elucidated and addressed. This paper reports evaluated observations from survey records captured through a cross-sectional observational study regarding owned canine populations in this South African province. We used logistic regression modeling to predict variables associated with risk of nonvaccination of rabies in owned dogs. The study indicated that husbandry practices, rabies knowledge, geographical area/location, and the ages of dogs were important factors associated with the risk of nonvaccination. High population turnover, together with large free roaming dog populations, compromised the levels of vaccination achieved and contributed to the persistence of dog rabies in the province. Dog owners in this study also reported that they were more likely to present their dogs for vaccination when the vaccines were free of charge (52% and less than a kilometer from their homes (91%. It has been suggested that effective dog rabies control

  11. Phonon dispersion in vanadium

    International Nuclear Information System (INIS)

    Ivanov, A.S.; Rumiantsev, A.Yu.

    1999-01-01

    Complete text of publication follows. Phonon dispersion curves in Vanadium metal are investigated by neutron inelastic scattering using three-axis spectrometers. Due to extremely low coherent scattering amplitude of neutrons in natural isotope mixture of vanadium the phonon frequencies could be determined in the energy range below about 15 meV. Several phonon groups were measured with the polarised neutron scattering set-up. It is demonstrated that the intensity of coherent inelastic scattering observed in the non-spin-flip channel vanishes in the spin-flip channel. The phonon density of states is measured on a single crystal keeping the momentum transfer equal to a vector of reciprocal lattice where the coherent inelastic scattering is suppressed. Phonon dispersion curves in vanadium, as measured by neutron and earlier by X-ray scattering, are described in frames of a charge-fluctuation model involving monopolar and dipolar degrees of freedom. The model parameters are compared for different transition metals with body-centred cubic-structure. (author)

  12. Dispersion and current measurements

    International Nuclear Information System (INIS)

    Boelskifte, S.

    1986-04-01

    A model for the simulation of particle movements in water should incorporate the mutual distance dependent correlation. As long as reliable data are given accessible a model can be created of the dispersion in a given area from a statistical description of turbulence. Current measurements have been performed in an area north of the Swedish nuclear power plant Barsebaeck, and statistical time series analysis have made it possible to estimate multivariate autoregressive moving-average (ARMA) models for these data using the Box-Jenkins method. The correlation structure for the area has been investigated in detail. Transport and dispersion models for the marine environment are used in estimating doses to the population from the aquatic food chain. Some of these models are described with special emphasis on the time and length scales they cover. Furthermore, to illustrate the background of the simulation model, short introductuions are given to health physics, time series analysis, and turbulence theory. Analysis of the simulation model shows the relative importance of the different parameters. The model can be expanded to conditional simulation, where the current measurements are used directly to simulate the movement of one of the particles. Results from the model are also compared to results from a sampling of bioindicators (Fucus vesiculosus) along the Danish coast. The reliability of bioindicators in this kind of experiment is discussed. (author)

  13. Quantum optical rotatory dispersion

    Science.gov (United States)

    Tischler, Nora; Krenn, Mario; Fickler, Robert; Vidal, Xavier; Zeilinger, Anton; Molina-Terriza, Gabriel

    2016-01-01

    The phenomenon of molecular optical activity manifests itself as the rotation of the plane of linear polarization when light passes through chiral media. Measurements of optical activity and its wavelength dependence, that is, optical rotatory dispersion, can reveal information about intricate properties of molecules, such as the three-dimensional arrangement of atoms comprising a molecule. Given a limited probe power, quantum metrology offers the possibility of outperforming classical measurements. This has particular appeal when samples may be damaged by high power, which is a potential concern for chiroptical studies. We present the first experiment in which multiwavelength polarization-entangled photon pairs are used to measure the optical activity and optical rotatory dispersion exhibited by a solution of chiral molecules. Our work paves the way for quantum-enhanced measurements of chirality, with potential applications in chemistry, biology, materials science, and the pharmaceutical industry. The scheme that we use for probing wavelength dependence not only allows one to surpass the information extracted per photon in a classical measurement but also can be used for more general differential measurements. PMID:27713928

  14. Temporal genomic evolution of bird sex chromosomes

    DEFF Research Database (Denmark)

    Wang, Zongji; Zhang, Jilin; Yang, Wei

    2014-01-01

    BACKGROUND: Sex chromosomes exhibit many unusual patterns in sequence and gene expression relative to autosomes. Birds have evolved a female heterogametic sex system (male ZZ, female ZW), through stepwise suppression of recombination between chrZ and chrW. To address the broad patterns and complex...... driving forces of Z chromosome evolution, we analyze here 45 newly available bird genomes and four species' transcriptomes, over their course of recombination loss between the sex chromosomes. RESULTS: We show Z chromosomes in general have a significantly higher substitution rate in introns and synonymous...... ('fast-Z' evolution). And species with a lower level of intronic heterozygosities tend to evolve even faster on the Z chromosome. Further analysis of fast-evolving genes' enriched functional categories and sex-biased expression patterns support that, fast-Z evolution in birds is mainly driven by genetic...

  15. Microbiological survey of birds of prey pellets.

    Science.gov (United States)

    Dipineto, Ludovico; Bossa, Luigi Maria De Luca; Pace, Antonino; Russo, Tamara Pasqualina; Gargiulo, Antonio; Ciccarelli, Francesca; Raia, Pasquale; Caputo, Vincenzo; Fioretti, Alessandro

    2015-08-01

    A microbiological survey of 73 pellets collected from different birds of prey species housed at the Wildlife Rescue and Rehabilitation Center of Napoli (southern Italy) was performed. Pellets were analyzed by culture and biochemical methods as well as by serotyping and polymerase chain reaction. We isolated a wide range of bacteria some of them also pathogens for humans (i.e. Salmonella enterica serotype Typhimurium, Campylobacter coli, Escherichia coli O serogroups). This study highlights the potential role of birds of prey as asymptomatic carriers of pathogenic bacteria which could be disseminated in the environment not only through the birds of prey feces but also through their pellets. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Breeding bird response to juniper woodland expansion

    Science.gov (United States)

    Rosenstock, Steven S.; van Riper, Charles

    2001-01-01

    In recent times, pinyon (Pinus spp.)-juniper (Juniperus spp.) woodlands have expanded into large portions of the Southwest historically occupied by grassland vegetation. From 1997-1998, we studied responses of breeding birds to one-seed juniper (J. monosperma) woodland expansion at 2 grassland study areas in northern Arizona. We sampled breeding birds in 3 successional stages along a grassland-woodland gradient: un-invaded grassland, grassland undergoing early stages of juniper establishment, and developing woodland. Species composition varied greatly among successional stages and was most different between endpoints of the gradient. Ground-nesting grassland species predominated in uninvaded grassland but declined dramatically as tree density increased. Tree- and cavity-nesting species increased with tree density and were most abundant in developing woodland. Restoration of juniper-invaded grasslands will benefit grassland-obligate birds and other wildlife.

  17. Chlamydia psittaci in birds of prey, Sweden

    Directory of Open Access Journals (Sweden)

    Maria Blomqvist

    2012-05-01

    Full Text Available Background: Chlamydia psittaci is an intracellular bacterium primarily causing respiratory diseases in birds but may also be transmitted to other animals, including humans. The prevalence of the pathogen in wild birds in Sweden is largely unknown. Methods: DNA was extracted from cloacae swabs and screened for C. psittaci by using a 23S rRNA gene PCR assay. Partial 16S rRNA and ompA gene fragments were sequence determined and phylogenies were analysed by the neighbour-joining method. Results and conclusion: The C. psittaci prevalence was 1.3% in 319 Peregrine Falcons and White-tailed Sea Eagles, vulnerable top-predators in Sweden. 16S rRNA and ompA gene analysis showed that novel Chlamydia species, as well as novel C. psittaci strains, are to be found among wild birds.

  18. Light-Activated Magnetic Compass in Birds

    DEFF Research Database (Denmark)

    Solov'yov, Ilia; Greiner, Walter

    2013-01-01

    Migrating birds fly thousand miles without having a map, or a GPS unit. But they may carry their own sensitive navigational tool, which allows them "see" the Earth’s magnetic field. Here we review the important physical and chemical constraints on a possible compass sensor and discuss the suggest......Migrating birds fly thousand miles without having a map, or a GPS unit. But they may carry their own sensitive navigational tool, which allows them "see" the Earth’s magnetic field. Here we review the important physical and chemical constraints on a possible compass sensor and discuss...... the suggestion that radical pairs in a photoreceptor cryptochrome might provide a biological realization for a magnetic compass. Finally, we review the current evidence supporting a role for radical pair reactions in the magnetic compass of birds....

  19. Visual perception and social foraging in birds.

    Science.gov (United States)

    Fernández-Juricic, Esteban; Erichsen, Jonathan T; Kacelnik, Alex

    2004-01-01

    Birds gather information about their environment mainly through vision by scanning their surroundings. Many prevalent models of social foraging assume that foraging and scanning are mutually exclusive. Although this assumption is valid for birds with narrow visual fields, these models have also been applied to species with wide fields. In fact, available models do not make precise predictions for birds with large visual fields, in which the head-up, head-down dichotomy is not accurate and, moreover, do not consider the effects of detection distance and limited attention. Studies of how different types of visual information are acquired as a function of body posture and of how information flows within flocks offer new insights into the costs and benefits of living in groups.

  20. Behavior of emu bird (Dromaius novaehollandiae

    Directory of Open Access Journals (Sweden)

    V. R. Patodkar

    Full Text Available Emu is the second largest living bird of world belonging to order Ratite. This order is of flightless birds with flat breast bone and it includes emu, ostrich, rhea, cassowary and kiwi. Emus are reared commercially in many parts of the world for their meat, oil, skin and feathers, which are of high economic value. The anatomical and physiological features of these birds appear to be suitable for temperate and tropical climatic conditions. Emu is newly introduced species in India. Although emu farming is considered to be economical, we have to study the behavior of emus to increase the profitability by providing housing, feeding and breeding facilities more or less same as that of in wild condition during their rearing in captivity and we will have to carry out comparative study of behavior in captivity as well as in wild condition. [Vet World 2009; 2(11.000: 439-440