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Bourouiba L.,Massachusetts Institute of Technology | Wu J.,York University | Newman S.,Emergency Center for Transboundary Animal Diseases | Takekawa J.,U.S. Geological Survey | And 6 more authors.
Journal of the Royal Society Interface | Year: 2010

Virulent outbreaks of highly pathogenic avian influenza (HPAI) since 2005 have raised the question about the roles of migratory and wild birds in the transmission of HPAI. Despite increased monitoring, the role of wild waterfowl as the primary source of the highly pathogenic H5N1 has not been clearly established. The impact of outbreaks of HPAI among species of wild birds which are already endangered can nevertheless have devastating consequences for the local and non-local ecology where migratory species are established. Understanding the entangled dynamics of migration and the disease dynamics will be key to prevention and control measures for humans, migratory birds and poultry. Here, we present a spatial dynamic model of seasonal migration derived from first principles and linking the local dynamics during migratory stopovers to the larger scale migratory routes. We discuss the effect of repeated epizootic at specific migratory stopovers for bar-headed geese (Anser indicus). We find that repeated deadly outbreaks of H5N1 on stopovers during the autumn migration of bar-headed geese could lead to a larger reduction in the size of the equilibrium bird population compared with that obtained after repeated outbreaks during the spring migration. However, the opposite is true during the first few years of transition to such an equilibrium. The age-maturation process of juvenile birds which aremore susceptible to H5N1 reinforces this result. © 2010 The Royal Society. Source


Gilbert M.,Roosevelt University | Gilbert M.,INRS - Institute National de la Recherche Scientifique | Newman S.H.,EMPRES Wildlife Unit | Takekawa J.Y.,U.S. Geological Survey | And 16 more authors.
EcoHealth | Year: 2010

Highly pathogenic avian influenza (HPAI) H5N1 virus persists in Asia, posing a threat to poultry, wild birds, and humans. Previous work in Southeast Asia demonstrated that HPAI H5N1 risk is related to domestic ducks and people. Other studies discussed the role of migratory birds in the long distance spread of HPAI H5N1. However, the interplay between local persistence and long-distance dispersal has never been studied. We expand previous geospatial risk analysis to include South and Southeast Asia, and integrate the analysis with migration data of satellite-tracked wild waterfowl along the Central Asia flyway. We find that the population of domestic duck is the main factor delineating areas at risk of HPAI H5N1 spread in domestic poultry in South Asia, and that other risk factors, such as human population and chicken density, are associated with HPAI H5N1 risk within those areas. We also find that satellite tracked birds (Ruddy Shelduck and two Bar-headed Geese) reveal a direct spatio-temporal link between the HPAI H5N1 hot-spots identified in India and Bangladesh through our risk model, and the wild bird outbreaks in May-June-July 2009 in China (Qinghai Lake), Mongolia, and Russia. This suggests that the continental-scale dynamics of HPAI H5N1 are structured as a number of persistence areas delineated by domestic ducks, connected by rare transmission through migratory waterfowl. © 2011 The Author(s). Source


Dixon A.,International Wildlife Consultants Ltd | Maming R.,Xinjiang Institute of Ecology and Geography | Gunga A.,Wildlife Science and Conservation Center | Purev-Ochir G.,Wildlife Science and Conservation Center | Batbayar N.,Wildlife Science and Conservation Center
Bird Conservation International | Year: 2013

We report a large number of raptors electrocuted on recently erected electricity distribution lines in the open landscapes of the Mongolian steppe and Qinghai-Tibetan plateau, China. Upland Buzzards Buteo hemilasius and Saker Falcons Falco cherrug, characteristic raptors of these bioregions, were among those found to be electrocuted. Raptor electrocution was a consequence of poorly designed hardware configurations on anchor poles along surveyed lines on the Qinghai-Tibetan Plateau and, additionally, on line poles in the Mongolian steppe. The design flaws were upright pin-insulators on earthed crossarms and the use of jump wires that passed over crossarms via pin insulators on anchor poles. Targeted mitigation of anchor poles could significantly reduce the incidence of electrocution on the lines surveyed on the Qinghai-Tibetan Plateau, whilst all poles on the lines surveyed in the Mongolian steppe require remediation to make them safe for raptors. The Mongolian steppe and the Qinghai-Tibetan Plateau are bioregions that hold the largest breeding and wintering populations of the globally threatened Saker Falcon. The existing and growing network of dangerous electricity distribution lines in these regions may potentially impact the Saker Falcon population, thus we suggest that preventative and/or mitigation measures are implemented. © BirdLife International 2013. Source


Zhan X.,University of Cardiff | Zhan X.,CAS Institute of Zoology | Dixon A.,International Wildlife Consultants Ltd | Batbayar N.,Wildlife Science and Conservation Center | And 19 more authors.
Heredity | Year: 2015

Recent years have seen considerable progress in applying single nucleotide polymorphisms (SNPs) to population genetics studies. However, relatively few have attempted to use them to study the genetic differentiation of wild bird populations and none have examined possible differences of exonic and intronic SNPs in these studies. Here, using 144 SNPs, we examined population genetic differentiation in the saker falcon (Falco cherrug) across Eurasia. The position of each SNP was verified using the recently sequenced saker genome with 108 SNPs positioned within the introns of 10 fragments and 36 SNPs in the exons of six genes, comprising MHC, MC1R and four others. In contrast to intronic SNPs, both Bayesian clustering and principal component analyses using exonic SNPs consistently revealed two genetic clusters, within which the least admixed individuals were found in Europe/central Asia and Qinghai (China), respectively. Pairwise D analysis for exonic SNPs showed that the two populations were significantly differentiated and between the two clusters the frequencies of five SNP markers were inferred to be influenced by selection. Central Eurasian populations clustered in as intermediate between the two main groups, consistent with their geographic position. But the westernmost populations of central Europe showed evidence of demographic isolation. Our work highlights the importance of functional exonic SNPs for studying population genetic pattern in a widespread avian species. © 2015 Macmillan Publishers Limited All rights reserved. Source


Dixon A.,International Wildlife Consultants Ltd | Purev-Ochir G.,Wildlife Science and Conservation Center | Galtbalt B.,Wildlife Science and Conservation Center | Batbayar N.,Wildlife Science and Conservation Center
Journal of Raptor Research | Year: 2013

The use of power line support structures as nesting sites enables some raptors and corvids to increase their breeding range and/or density in landscapes where alternative nest sites are limited. We report on the use of power poles for nesting by two nest-building species, Common Raven (Corvus corax) and Upland Buzzard (Buteo hemilasius), and two falcon species, Saker Falcon (Falco cherrug) and Eurasian Kestrel (Falco tinnunculus) in the nest-site-limited steppes of central Mongolia. Various power pole designs differed in their attractiveness to nest-building species, with structures that provided stable support and shelter being significantly favored. Trials of artificial nest barrels to (i) provide alternative nest sites on favored nesting support structures and (ii) provide additional nest sites on unfavored support structures, failed to induce nest-building species to shift their nest location in the first instance or to increase overall breeding density of large raptors and corvids in the second case. However, both trials resulted in large increases in the number of nesting Eurasian Kestrels. © 2013 The Raptor Research Foundation, Inc. Source

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