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Castleton-on-Hudson, NY, United States

Stoner T.D.,St Jude Childrens Research Hospital | Krauss S.,St Jude Childrens Research Hospital | DuBois R.M.,St Jude Childrens Research Hospital | Negovetich N.J.,St Jude Childrens Research Hospital | And 7 more authors.
Journal of Virology | Year: 2010

Influenza viruses of the N1 neuraminidase (NA) subtype affecting both animals and humans caused the 2009 pandemic. Anti-influenza virus NA inhibitors are crucial early in a pandemic, when specific influenza vaccines are unavailable. Thus, it is urgent to confirm the antiviral susceptibility of the avian viruses, a potential source of a pandemic virus. We evaluated the NA inhibitor susceptibilities of viruses of the N1 subtype isolated from wild waterbirds, swine, and humans. Most avian viruses were highly or moderately susceptible to oseltamivir (50% inhibitory concentration [IC50], <5.1 to 50 nM). Of 91 avian isolates, 7 (7.7%) had reduced susceptibility (IC50, >50 nM) but were sensitive to the NA inhibitors zanamivir and peramivir. Oseltamivir susceptibility ranged more widely among the waterbird viruses (IC50, 0.5 to 154.43 nM) than among swine and human viruses (IC50, 0.33 to 2.56 nM). Swine viruses were sensitive to oseltamivir, compared to human seasonal H1N1 isolated before 2007 (mean IC50, 1.4 nM). Avian viruses from 2007 to 2008 were sensitive to oseltamivir, in contrast to the emergence of resistant H1N1 in humans. Susceptibility remained high to moderate over time among influenza viruses. Sequence analysis of the outliers did not detect molecular markers of drug-resistance (e.g., H275Y NA mutation [N1 numbering]) but revealed mutations outside the NA active site. In particular, V267I, N307D, and V321I residue changes were found, and structural analyses suggest that these mutations distort hydrophobic pockets and affect residues in the NA active site. We determined that natural oseltamivir resistance among swine and wild waterbirds is rare. Minor naturally occurring variants in NA can affect antiviral susceptibility. Copyright © 2010, American Society for Microbiology. All Rights Reserved. Source

Dorr B.S.,Mississippi State University | Burger L.W.,Mississippi State University | Barras S.C.,Wildlife Services | Godwin K.C.,Mississippi State University
Wildlife Society Bulletin | Year: 2012

Estimating the catfish aquaculture production losses that can be attributed to double-crested cormorants (Phalacrocorax auritus) has proved problematic because knowledge of the distribution of cormorants on catfish aquaculture is lacking. We evaluated use versus availability of various production pond types and landscape-scale factors affecting the distribution of cormorants on channel catfish (Ictalurus punctatus) aquaculture facilities in Mississippi, USA Cormorant distribution on aquaculture pond types indicated selection against brood-fish ponds, neutral selection on fingerling ponds, and selection for food-fish ponds (n = 29, Chesson's a = 0.19, 0.36, and 0.45, respectively). Modeled and validated correct classification rate (CCR) of general linear mixed models of cormorant occupancy of clusters of catfish ponds indicated seasonality of use and roost distance from aquaculture ponds was predictive (CCR = 81% and 71%, respectively). Modeled and validated ordinal models of levels of use (low,moderate, high) were less predictive (CCR = 67% and 59%, respectively). However, predictability within use levels for the validation data set was mixed, ranging from 0.19 to 0.86. Odds ratios indicate both higher risk of occupancy and levels of use over the period February-April relative to October. Management efforts targeted during this time frame will have the greatest impact in reducing depredation losses. The majority of cormorants occurred on food-fish ponds. Consequently estimates of economic loss should be revisited and refined based on distributional information provided in this study. Published 2012. This article is a U.S. Government work and is in the public domain in the USA. © 2011 The Wildlife Society. Source

Kim B.I.,Emory University | Kim B.I.,Centers for Disease Control and Prevention | Blanton J.D.,Centers for Disease Control and Prevention | Gilbert A.,Centers for Disease Control and Prevention | And 3 more authors.
Zoonoses and Public Health | Year: 2014

The direct and interactive effects of climate change on host species and infectious disease dynamics are likely to initially manifest\ at latitudinal extremes. As such, Alaska represents a region in the United States for introspection on climate change and disease. Rabies is enzootic among arctic foxes (Vulpes lagopus) throughout the northern polar region. In Alaska, arctic and red foxes (Vulpes vulpes) are reservoirs for rabies, with most domestic animal and wildlife cases reported from northern and western coastal Alaska. Based on passive surveillance, a pronounced seasonal trend in rabid foxes occurs in Alaska, with a peak in winter and spring. This study describes climatic factors that may be associated with reported cyclic rabies occurrence. Based upon probabilistic modelling, a stronger seasonal effect in reported fox rabies cases appears at higher latitudes in Alaska, and rabies in arctic foxes appear disproportionately affected by climatic factors in comparison with red foxes. As temperatures continue a warming trend, a decrease in reported rabid arctic foxes may be expected. The overall epidemiology of rabies in Alaska is likely to shift to increased viral transmission among red foxes as the primary reservoir in the region. Information on fox and lemming demographics, in addition to enhanced rabies surveillance among foxes at finer geographic scales, will be critical to develop more comprehensive models for rabies virus transmission in the region. © 2013 Blackwell Verlag GmbH. Source

Washburn B.E.,National Wildlife Research Center | Bernhardt G.E.,National Wildlife Research Center | Kutschbach-Brohl L.,National Wildlife Research Center | Chipman R.B.,Wildlife Services | Francoeur L.C.,Port Authority of New York and New Jersey
Condor | Year: 2013

Coastal urban environments provide a potentially diverse source of food for gulls, including items of marine, terrestrial, and anthropogenic origin. Our objective was to examine variation in the diet and use of feeding habitat of four species of gulls, the Laughing (Leucophaeus atricilla), Herring (Larus argentatus), Great Blackbacked (L. marinus), and Ring-billed (L. delawarensis), at a coastal-urban interface. We necropsied, identified the sex and age class, and quantified the stomach contents of 1053 Laughing, 249 Herring, 67 Great Black-backed, and 31 Ring-billed Gulls collected near the New York City metropolitan area in 2003 and 2004. Great Black-backed Gulls specialized on marine food s, whereas Ring-billed Gulls were generalists. Laughing Gulls and Herring Gulls favored marine food s and foraged in marine habitats but also used terrestrial and anthropogenic food sources. We found evidence that demographics influenced the gulls' choice of diet and use of feeding habitat. Laughing Gulls and Herring Gulls switched their use of feeding habitats at various stages of breeding, exploiting terrestrial prey and feeding habitats most during chick rearing. Interspecific and intraspecific differences in the four species' diet and use of feeding habitat apparently allow for their coexistence at this coastal-urban interface. © The Cooper Ornithological Society 2013. Source

Hurley M.A.,9 Highway 93 N | Zager P.,316 16th Street | Hebblewhite M.,University of Montana | Garton E.O.,University of Idaho | And 3 more authors.
Wildlife Monographs | Year: 2011

Manipulating predator populations is often posed as a solution to depressed ungulate populations. However, predator-prey dynamics are complex and the effect on prey populations is often an interaction of predator life history, climate, prey density, and habitat quality. The effect of predator removal on ungulate and, more specifically, mule deer (Odocoileus hemionus) populations has not been adequately investigated at a management scale. We tested the efficacy of removing coyotes (Canis latrans) and mountain lions (Puma concolor) for increasing survival and population growth rate of mule deer in southeastern Idaho, USA, during 1997-2003. We assigned 8 game management units (GMUs) to treatments under a 2 × 2 factorial design (treatments of coyote removal and lion removal) with 2 replicates of each treatment or reference area combination. We used methods typically available to wildlife managers to achieve predator removals and a combination of extensive and intensive monitoring in these 8 GMUs to test the hypothesis that predator removal increased vital rates and population growth rate of mule deer. We determined effects of predator removal on survival and causes of mortality in 2 intensive study sites, one with coyote and mountain lion removal and one without. We also considered the effects of other variables on survival including lagomorph abundance and climatic conditions. In these 2 intensive study areas, we monitored with radiotelemetry 250 neonates, 284 6-month-old fawns, and 521 adult females. At the extensive scale, we monitored mule deer population trend and December fawn ratios with helicopter surveys. Coyote removal decreased neonate mortality only when deer were apparently needed as alternate prey, thus removal was more effective when lagomorph populations were reduced. The best mortality model of mule deer captured at 6 months of age included summer precipitation, winter precipitation, fawn mass, and mountain lion removal. Over-winter mortality of adult female mule deer decreased with removal of mountain lions. Precipitation variables were included in most competing mortality models for all age classes of mule deer. Mountain lion removal increased fawn ratios and our models predicted fawn ratios would increase 6% at average removal rates (3.53/1,000 km 2) and 27% at maximum removal rates (14.18/1,000 km 2). Across our extensive set of 8 GMUs, coyote removal had no effect on December fawn ratios. We also detected no strong effect of coyote or mountain lion removal alone on mule deer population trend; the best population-growth-rate model included previous year's mountain lion removal and winter severity, yet explained only 27% of the variance in population growth rate. Winter severity in the current and previous winter was the most important influence on mule deer population growth. The lack of response in fawn ratio or mule deer abundance to coyote reduction at this extensive (landscape) scale suggests that decreased neonate mortality due to coyote removal is partially compensatory. Annual removal of coyotes was not an effectivemethod to increase mule deer populations in Idaho because coyote removal increased radiocollared neonate fawn survival only under particular combinations of prey densities and weather conditions, and the increase did not result in population growth. Coyote-removal programs targeted in areas where mortality of mule deer fawns is known to be additive and coyote-removal conditions are successful may influence mule deer population vital rates but likely will not change direction of population trend. Although mountain lion removal increased mule-deer survival and fawn ratios, we were unable to demonstrate significant changes in population trend with mountain lion removal. In conclusion, benefits of predator removal appear to be marginal and short term in southeastern Idaho and likely will not appreciably change long-term dynamics of mule deer populations in the intermountain west. © 2011 The Wildlife Society. Source

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