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Background 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. Methodology/Findings Here we used hydrogen isotopes (δD) 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,...
Background 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. Methodology/Findings Here we used hydrogen isotopes (δD) 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,...
We examined long-term databases concerning population status of scaup (lesser [Aythya affinis] and greater scaup [A. marila] combined) and harvest statistics of lesser scaup to identify factors potentially limiting population growth. Specifically, we explored evidence for and against the general hypotheses that scaup populations have declined in association with declining recruitment and/or female survival. We examined geographic heterogeneity in scaup demographic patterns that could yield evidence about potential limiting factors. Several biases exist in survey methodology used to estimate scaup populations and harvest statistics; however, none of these biases likely accounted for our major findings that (1) the...
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We examined long-term databases concerning population status of scaup (lesser [Aythya affinis] and greater scaup [A. marila] combined) and harvest statistics of lesser scaup to identify factors potentially limiting population growth. Specifically, we explored evidence for and against the general hypotheses that scaup populations have declined in association with declining recruitment and/or female survival. We examined geographic heterogeneity in scaup demographic patterns that could yield evidence about potential limiting factors. Several biases exist in survey methodology used to estimate scaup populations and harvest statistics; however, none of these biases likely accounted for our major findings that (1) the...
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Organisms that reproduce in temperate regions have limited time to produce offspring successfully, and this constraint is expected to be more pronounced in areas with short growing seasons. Information concerning how reproductive ecology of endotherms might be influenced by growing season length (GSL) is rare, and species that breed over a broad geographic range provide an opportunity to study the effects of time constraints on reproductive strategies. We analyzed data from a temperate-breeding bird, the lesser scaup Aythya affinis; hereafter scaup, collected at eight sites across a broad gradient of GSL to evaluate three hypotheses related to reproductive compensation in response to varying time constraints. Clutch...
Organisms that reproduce in temperate regions have limited time to produce offspring successfully, and this constraint is expected to be more pronounced in areas with short growing seasons. Information concerning how reproductive ecology of endotherms might be influenced by growing season length (GSL) is rare, and species that breed over a broad geographic range provide an opportunity to study the effects of time constraints on reproductive strategies. We analyzed data from a temperate-breeding bird, the lesser scaup Aythya affinis; hereafter scaup, collected at eight sites across a broad gradient of GSL to evaluate three hypotheses related to reproductive compensation in response to varying time constraints. Clutch...
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Wild lesser scaup from the Chesapeake Bay, captured and implanted with satellite transmitters for a separate ecology study, were opportunistically sampled for avian influenza. These data detail the virological sampling results, obtained post release, which include a single positive for clade 2.3.4.4 H5N1 virus of the A/goose/Guangdong/1/1996 (Gs/GD) H5N1 lineage of highly pathogenic IAV. These data also include the movements of the infected bird from release until death as well as four conspecifics marked and released concurrent with the HPAI positive bird. These data support a paired publication.
Ecologists and conservation biologists alike aim to understand factors determining the abundance and distribution of free-living organisms and to pinpoint why free-ranging animal populations decline. My broad goals were to test ecological hypotheses related to timing of breeding and offspring survival in lesser scaup ( Aythya affinis, hereafter scaup), a boreal-breeding diving duck species and to examine breeding-season explanations for why scaup populations remain below conservation goals. I demonstrated that timing of breeding and clutch size in scaup were remarkably consistent across a broad environmental gradient. Clutch initiation date was unaffected by growing season length (GSL) or latitude and was only marginally...
map background search result map search result map Time constraints in temperate-breeding species: influence of growing season length on reproductive strategies Lesser Scaup Breeding Probability and Female Survival on the Yukon Flats, Alaska Species richness and distributions of boreal waterbird broods in relation to nesting and brood-rearing habitats Lesser Scaup Nest Success and Duckling Survival on the Yukon Flats, Alaska Nest Survival of Scaup and Other Ducks in the Boreal Forest of Alaska Lesser scaup nesting ecology in relation to water chemistry and macroinvertebrates on the Yukon Flats, Alaska Telemetry data of a Lesser Scaup (Aythya affinis) positive for 2.3.4.4 Highly Pathogenic H5N1 Telemetry data of a Lesser Scaup (Aythya affinis) positive for 2.3.4.4 Highly Pathogenic H5N1 Nest Survival of Scaup and Other Ducks in the Boreal Forest of Alaska Species richness and distributions of boreal waterbird broods in relation to nesting and brood-rearing habitats Lesser scaup nesting ecology in relation to water chemistry and macroinvertebrates on the Yukon Flats, Alaska Lesser Scaup Breeding Probability and Female Survival on the Yukon Flats, Alaska Lesser Scaup Nest Success and Duckling Survival on the Yukon Flats, Alaska Time constraints in temperate-breeding species: influence of growing season length on reproductive strategies