contaminants and sea ducks in alaska and the circumpolar region.we review nesting sea duck population declines in alaska during recent decades and explore the possibility that contaminants may be implicated. aerial surveys of the surf scoter (melanitta perspicillata), white-winged scoter (m. fusca), black scoter (m. nigra), oldsqaw (clangula hyemalis), spectacled eider (somateria fischeri), and steller's eider (polysticta stellei) show long-term breeding population declines, especially the latter three species. the spectacled eider was recently classified th ...19957556023
an adenovirus linked to mortality and disease in long-tailed ducks (clangula hyemalis) in adenovirus was isolated from intestinal samples of two long-tailed ducks (clangula hyemalis) collected during a die-off in the beaufort sea off the north coast of alaska in 2000. the virus was not neutralized by reference antiserum against known group i, ii, or iii avian adenoviruses and may represent a new serotype. the prevalence of the virus was determined in live-trapped long-tailed ducks at the mortality site and at a reference site 100 km away where no mortality was observed. prevalence ...200314708993
helminth parasites of the bufflehead duck, bucephala albeola, wintering in the chihuahua desert with a checklist of helminth parasites reported from this host.the bufflehead duck (bucephala albeola) (mergini) ranges from alaska and canada to the united states and mexico. buffleheads ingest invertebrates as a major component of their food throughout life. puddle ducks (anatinae) change mainly to vegetable foods at an early age. loss of helminth parasite species and abundance in the fall migration has been reported for puddle ducks. this change in food has been hypothesized to cause some of the parasite loss. nothing was known about helminth community d ...200919245274
interspecies transmission and limited persistence of low pathogenic avian influenza genomes among alaska dabbling ducks.the reassortment and geographic distribution of low pathogenic avian influenza (lpai) virus genes are well documented, but little is known about the persistence of intact lpai genomes among species and locations. to examine persistence of entire lpai genome constellations in alaska, we calculated the genetic identities among 161 full-genome lpai viruses isolated across 4 years from five species of duck: northern pintail (anas acuta), mallard (anas platyrhynchos), american green-winged teal (anas ...201121964597
maintenance of influenza a viruses and antibody response in mallards (anas platyrhynchos) sampled during the non-breeding season in alaska.prevalence of influenza a virus (iav) infections in northern-breeding waterfowl has previously been reported to reach an annual peak during late summer or autumn; however, little is known about iav infection dynamics in waterfowl populations persisting at high-latitude regions such as alaska, during winter. we captured mallards (anas platyrhynchos) throughout the non-breeding season (august-april) of 2012-2015 in fairbanks and anchorage, the two largest cities in alaska, to assess patterns of ia ...201728837606
ingestion of petroleum by breeding mallard ducks: some effects on neonatal progeny. 19827092320
migration strategy affects avian influenza dynamics in mallards (anas platyrhynchos).studies of pathogen transmission typically overlook that wildlife hosts can include both migrant and resident populations when attempting to model circulation. through the application of stable isotopes in flight feathers, we estimated the migration strategy of mallards (anas platyrhynchos) occurring on california wintering grounds. our study demonstrates that mallards- a principal host of avian influenza virus (aiv) in nature, contribute differently to virus gene flow depending on migration str ...201222971007
cross-seasonal patterns of avian influenza virus in breeding and wintering migratory birds: a flyway perspective.abstract the spread of avian influenza viruses (aiv) in nature is intrinsically linked with the movements of wild birds. wild birds are the reservoirs for the virus and their migration may facilitate the circulation of aiv between breeding and wintering areas. this cycle of dispersal has become widely accepted; however, there are few aiv studies that present cross-seasonal information. a flyway perspective is critical for understanding how wild birds contribute to the persistence of aiv over l ...201121995264
interspecific exchange of avian influenza virus genes in alaska: the influence of trans-hemispheric migratory tendency and breeding ground sympatry.the movement and transmission of avian influenza viral strains via wild migratory birds may vary by host species as a result of migratory tendency and sympatry with other infected individuals. to examine the roles of host migratory tendency and species sympatry on the movement of eurasian low-pathogenic avian influenza (lpai) genes into north america, we characterized migratory patterns and lpai viral genomic variation in mallards (anas platyrhynchos) of alaska in comparison with lpai diversity ...201021073586
mx gene diversity and influenza association among five wild dabbling duck species (anas spp.) in (myxovirus-resistant) proteins are induced by interferon and inhibit viral replication as part of the innate immune response to viral infection in many vertebrates. influenza a virus appears to be especially susceptible to mx antiviral effects. we characterized exon 13 and the 3' utr of the mx gene in wild ducks, the natural reservoir of influenza virus and explored its potential relevance to influenza infection. we observed a wide range of intra- and interspecies variations. total nucleotide ...201020621205
pcb exposure in sea otters and harlequin ducks in relation to history of contamination by the exxon valdez oil spill.exposure to contaminants other than petroleum hydrocarbons could confound interpretation of exxon valdez oil spill effects on biota at prince william sound, alaska. hence, we investigated polychlorinated biphenyls (pcbs) in blood of sea otters and harlequin ducks sampled during 1998. pcb concentrations characterized by lower chlorinated congeners were highest in sea otters from the unoiled area, whereas concentrations were similar among harlequin ducks from the oiled and unoiled area. blood enzy ...201020132952
blood lead levels of wild steller's eiders (polysticta stelleri) and black scoters (melanitta nigra) in alaska using a portable blood lead analyzer.sea duck populations are declining in alaska. the reasons for the decline are not known; environmental lead exposure is one suspected cause. thirty wild steller's eider ducks (polysticta stelleri) and 40 wild black scoter ducks (melanitta nigra) were tested for blood lead levels using a portable blood lead analyzer (leadcare; esa, inc., chelmsford, massachusetts 01824, usa). sixty-seven and one-tenth percent of the sea ducks had undetectable blood lead levels, 30.0% had values indicating normal ...200617319136
aerial monitoring of marine waterfowl in the alaskan beaufort sea.the purpose of this study was to design and test a monitoring protocol for marine waterfowl in the central alaskan beaufort sea. the study provides an important case-study of how a long-term monitoring program may be affected by unanticipated human disturbances. because of its overwhelming and widespread abundance, relatively sedentary behavior, ease in counting, and the extensive historical database, the long-tailed duck (clangula hyemalis) was selected as the focal species. two null hypotheses ...200516160776
an evaluation of marine bird population trends following the exxon valdez oil spill, prince william sound, alaska.we examined post-spill trends (1989-1998) of marine bird populations in prince william sound (pws) following the exxon valdez oil spill (evos) to evaluate recovery of injured taxa. two criteria were employed. first, we examined population trends of injured taxa only in the oiled area of pws using regression models. second, we examined population trends of injured taxa in the oiled area relative to the unoiled area using homogeneity of the slopes tests. we considered a population recovering if th ...200111381751
a comprehensive rabies control program in 1975 the state of alaska initiated a comprehensive rabies control program. lay vaccinators trained and certified by the state provided animal vaccination in rural areas. from 1975 through 1980, 182 persons received post-exposure rabies prophylaxis with human rabies immune globulin (hrig) plus duck embryo vaccine (dev), or human diploid cell vaccine (hdcv), while 2,569 persons initially thought to have been exposed were not treated after consultation, at a cost saving of approximately $3,220,2 ...19827065317
harlequin duck population injury and recovery dynamics following the 1989 exxon valdez oil spill.the 1989 exxon valdez oil spill caused significant injury to wildlife populations in prince william sound, alaska, usa. harlequin ducks (histrionicus histrionicus) were particularly vulnerable to the spill and have been studied extensively since, leading to one of the most thorough considerations of the consequences of a major oil spill ever undertaken. we compiled demographic and survey data collected since the spill to evaluate the timing and extent of mortality using a population model. durin ...201021049885
examining the hemagglutinin subtype diversity among wild duck-origin influenza a viruses using ethanol-fixed cloacal swabs and a novel rt-pcr method.this study presents an interconnected approach for circumventing two inherent limitations associated with studies defining the natural history of influenza a viruses in wild birds. the first limiting factor is the ability to maintain a cold chain from specimen collection to the laboratory when study sites are in more remote locations. the second limiting factor is the ability to identify all influenza a virus ha subtypes present in an original sample. we report a novel method for molecular subty ...200818308356
using rrt-pcr analysis and virus isolation to determine the prevalence of avian influenza virus infections in ducks at minto flats state game refuge, alaska, during august 2005.this study describes surveillance for avian influenza viruses (aiv) in the minto flats state game refuge, high-density waterfowl breeding grounds in alaska. five hundred paired cloacal samples from dabbling ducks (northern pintail, mallard, green wing teal, and widgeon) were placed into ethanol and viral transport medium (vtm). additional ethanol-preserved samples were taken. of the ethanol-preserved samples, 25.6% were aiv rna-positive by real-time rt-pcr. the hemagglutinin (ha) and neuraminida ...200717541700
new minto virus: a new rhabdovirus from ticks in alaska.three strains of a virus were isolated from haemaphysalis leporis-palustris (packard) ticks removed from snowshoe hares (lepus americanus erxleben) in east central alaska. we suggest that the virus be named new minto for the location in which the ticks were collected. prototype new minto virus is sensitive to the action of sodium deoxycholate and kills suckling mice by the intracerebral but not intraperitoneal route; weaned mice do not die after intracerebral, intraperitoneal, or subcutaneous in ...1978638895
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