trace elements in sea ducks of the alaskan arctic coast: patterns of variation among species, sexes, and ages.climate change and increasing industrialization in the arctic call for the collection of reference data for assessing changes in contaminant levels. for migratory birds, measuring and interpreting changes in trace element burdens on arctic breeding areas require insights into factors such as sex, body size, or wintering area that may modify patterns independently of local exposure. in the alaskan arctic, we determined levels of trace elements in liver and kidney of common eiders (somateria molli ...201627272534
environmental contaminants in four eider species from alaska and arctic russia.population declines in four species of eider; common (somateria mollissima), king (somateria spectabilis), spectacled (somateria fischeri) and steller's (polysticta stelleri), have raised concerns about exposure to contaminants. livers and kidney tissues were collected from eiders in alaska and russia for organic and elemental analyses. results showed that organochlorine and many elemental levels were below toxic thresholds; however, in many cases, cadmium, copper, lead and serenium appeared hig ...200212152828
validating quantitative fatty acid signature analysis to estimate diets of spectacled and steller's eiders (somateria fischeri and polysticta stelleri).fatty acid (fa) signature analysis has been used to study foraging ecology and food webs in marine ecosystems. this powerful method provides information about diets over an extended time period (e.g., 2-4 weeks), rather than just the most recent meal as with most traditional approaches. using consumer fa signatures, along with a comprehensive database of diet fa signatures, and accounting for consumer fa metabolism, it is possible to estimate the proportions of diet items in the consumer's diet ...201019652982
carbon isotopic fractionation in eider adipose tissue varies with fatty acid structure: implications for trophic studies.carbon isotopic fractionation was investigated in fatty acids (fa) of adipose tissue and blood serum of threatened steller's eiders (polysticta stelleri) and spectacled eiders (somateria fischeri) relative to the fa in their diets. captive eiders were fed a known diet for 180 days with serum sampled at 60, 120 and 180 days immediately after a 12 fast; adipose was collected at 180 days. essential fa (efa) in the adipose showed varying degrees of isotope fractionation (0-4‰), depending on fa struc ...201122031744
the influence of year, laying date, egg fertility and incubation, individual hen, hen age and mass and clutch size on maternal immunoglobulin y concentration in captive steller's and spectacled eider egg yolk.steller's eiders and spectacled eiders are sea duck species whose populations have declined significantly and infectious diseases could influence offspring survival. therefore, the maternal transfer of immunoglobulin y (igy) into yolk was investigated in captive steller's and spectacled eiders during the 2007-2013 breeding seasons. this project had two objectives: establish baseline igy levels in steller's and spectacled eider yolk under controlled captive conditions and evaluate the effect of y ...201525892022
distribution and numbers of steller's eiders (polysticta stelleri) during migrations and wintering in the barents and white sea water area. 200112918428
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
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
molecular typing of escherichia coli strains associated with threatened sea ducks and near-shore marine habitats of south-west alaska, sea ducks winter in coastal habitats at remote, non-industrialized areas, as well as in proximity to human communities and industrial activity. we evaluated prevalence and characteristics of escherichia coli strains in faecal samples of steller's eiders (polysticta stelleri; n = 122) and harlequin ducks (histrionicus histrionicus; n = 21) at an industrialized site and steller's eiders (n = 48) at a reference site, and compared these strains with those isolated from water samples from ...201123761259
polycyclic aromatic hydrocarbon exposure in steller's eiders (polysticta stelleri) and harlequin ducks (histronicus histronicus) in the eastern aleutian islands, alaska, usa.seaducks may be affected by harmful levels of polycyclic aromatic hydrocarbons (pahs) at seaports near the arctic. as an indicator of exposure to pahs, we measured hepatic enzyme 7-ethoxyresorufin-o-deethylase activity (erod) to determine cytochrome p4501a induction in steller's eiders (polysticta stelleri) and harlequin ducks (histronicus histronicus) from unalaska, popof, and unga islands (ak, usa) in 2002 and 2003. we measured pahs and organic contaminants in seaduck prey samples and polychlo ...200718020694
the body size-dependent diet composition of north american sea ducks in winter.daily food requirements scale with body mass and activity in animals. while small species of birds have higher mass-specific field metabolic rates than larger species, larger species have higher absolute energy costs. under energy balance, we thus expect the small species to have a higher energy value diet. also the weight and time constraints for flighted and diurnal foragers should set a maximum to the amount of prey items taken in one meal and to the daily number of meals, respectively. furth ...201323755266
evidence for limited exchange of avian influenza viruses between seaducks and dabbling ducks at alaska peninsula coastal lagoons.avian influenza virus (aiv) prevalence and sequence data were analyzed for steller's eiders (polysticta stelleri) to assess the role of this species in transporting virus genes between continents and maintaining a regional viral reservoir with sympatric northern pintails (anas acuta). aiv prevalence was 0.2% at izembek lagoon and 3.9% at nelson lagoon for steller's eiders and 11.2% for northern pintails at izembek lagoon. phylogenetic analysis of 13 aivs from steller's eiders revealed that 4.9% ...201121766196
[microsomacanthus polystictae sp. n. and other cestodes of the family hymenolepididae (cyclophyllidea) from steller's eider polysticta stelleri from the chaun lowlands (northwestern chukotka)].8 species of cestodes belonging to the family hymenolepididae were recorded from polysticta stelleri (pall.) in the chaun lowland. a new species of hymenolepidids, microsomacanthus polystictae sp. n., differing from close (by the length of proboscis hooks) species of the genus in the structure and size of the copulatory organ is described. brief diagnosis of the new species: cestodes small, specimens ending with hermaphrodite proglottids 2.44 to 2.91 mm long. proboscis hooks 0.038 to 0.042 mm lo ...20073387123
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