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Spectacled eider (Somateria fischeri) populations in western Alaska are now less than 4% of the numbers estimated in the early 1970s. In 1992, an estimated 1721 nesting pairs remained on the Yukon-Kuskokwim Delta. Causes of this rapid and continuing decline of -14% per year are undocumented. Many aspects of spectacled eider biology remain unknown, including their marine foraging habitats, food items, migratory movements, and population ecology. A review of some biological characteristics and possible threats to the species suggests the importance of quantifying potential impacts from parasites and disease, subsistence harvest, predation during brood rearing, and alteration of Bering Sea food resources. Factors causing...
Categories: Publication; Types: Citation; Tags: Arctic
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We studied gyrfalcon (Falco rusticolus) food delivery and feeding behavior during the nestling period in central West Greenland during the 2000 and 2001 field seasons. We used time-lapse video cameras installed at three nests to record 2677.25 hours of nestling video. Ptarmigan delivered to nests were usually plucked prior to delivery and included the breast and superior thoracic vertebrae. Arctic hare leverets were rarely plucked and often delivered in parts. The most commonly delivered leveret part was the hind legs attached to the lower back. Passerines were rarely plucked and usually delivered whole. After feeding the young, adults removed 20.9% of prey items from the nest, which included items both with and...
Categories: Publication; Types: Citation; Tags: Arctic
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Various methods were investigated for assessing the relationship between wind-hardened snow (upsik) and forage availability to reindeer. Mean bottom area of individual craters was not a function of depth, hardness or integrated hardness. Individual crater area was partially dependent on specific cratering time (r2 = .60). Cratering time per active period increased with integrated snow hardness (r2 = .88). Number of craters and total area cratered increased with decreasing site hardness. Reindeer always cratered microsites of lesser depth and hardness than found in the general feeding site. A threefold decrease in snow hardness resulted in a fourfold increase in forage availability
Categories: Publication; Types: Citation; Tags: Arctic
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The Late Wisconsinan and Holocene record of the Atlantic walrus is known from numerous collections of bones and tusks from Arctic Canada and south to North Carolina, as well as from many archaeological sites in the Arctic and Subarctic. In contrast, the Pacific walrus has no dated Late Wisconsinan or early Holocene record in North America, and it may have been displaced into the northwest Pacific at Last Glacial Maximum (LGM). The Atlantic walrus rapidly exploited newly deglaciated territory, moving northward from its LGM refugium and reaching the Bay of Fundy by 12800 B.P., the Grand Banks by 12500 B.P., southern Labrador by 11500 B.P., and the central Canadian Arctic Archipelago (CAA) by 9700 B.P. Its southern...
Categories: Publication; Types: Citation; Tags: Arctic
The article explores oil and natural gas development in the Arctic. While several commentators have argued that an increase in Arctic petroleum production in the years to come will follow directly from an increased demand for energy, our study finds that oil and natural gas production in the Arctic is dependent on a range of variables. By using climate-driven changes as a baseline, we examine spill-over effects and conditions that are important for further Arctic hydrocarbon production. Using the available literature from different scientific fields, this article provides a broad and nuanced perspective on the much debated question of whether or not the Arctic will become a region driven by oil and gas production.
Categories: Publication; Types: Citation; Tags: Arctic, Gas, Oil
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Worldwide, some caribou (Rangifer tarandus) populations are experiencing declines due partially to the expansion of industrial development. Caribou can exhibit behavioral avoidance of development, leading to indirect habitat loss, even if the actual footprint is small. Thus, it is important to understand before construction begins how much habitat might be affected by proposed development. In northern Alaska, an industrial road that has been proposed to facilitate mining transects a portion of the Western Arctic caribou herd's winter range. To understand how winter habitat use might be affected by the road, we estimated resource selection patterns during winter for caribou in a study area surrounding the proposed...
Categories: Publication; Types: Citation; Tags: Arctic
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Arctic ecosystems are changing at an unprecedented rate. How Arctic species are able to respond to such environmental change is partially dependent on the connections between local and broadly distributed populations. For species like the Long-tailed Duck (Clangula hyemalis), we have limited telemetry and band-recovery information from which to infer population structure and migratory connectivity; however, genetic analyses can offer additional insights. To examine population structure in the Long-tailed Duck, we characterized variation at mtDNA control region and microsatellite loci among four breeding areas in Alaska, Canada, and Russia. We observed significant differences in the variance of mtDNA haplotype frequencies...
Categories: Publication; Types: Citation; Tags: Arctic
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The attached data are apatite and zircon fission track measurements from rock samples collected across the western Brooks Range. Table 1 contains descriptive information on each sample. Tables 2a, 2b, 2c, 2d and 2e contain single grain, apatite fission track age data for samples from each of five datasets that comprise the overall apatite fission track age dataset. Tables 3a, 3b, 3c, and 3d contain apatite fission track length data for samples from four of the five datasets that comprise the overall apatite fission track length dataset. The oldest of the five datasets has no accompanying track length data. Table 4 contains summary information for each of the apatite fission track age samples. Table 5 contains summary...
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Region(s) of distribution of White Sea Eelpout (Lycodes marisalbi) Knipowitsch, 1906 in the Arctic as digitized for U.S. Geological Survey Scientific Investigations Report 2016-5038. For details on the project and purpose, see the report at https://doi.org/10.3133/sir20165038. Complete metadata for the collection of species datasets is in the metadata document "Dataset_for_Alaska_Marine_Fish_Ecology_Catalog.xml" at https://doi.org/10.5066/F7M61HD7. Source(s) for this digitized data layer are listed in the metadata Process Steps section. Note that the original source may show an extended area; some datasets were limited to the published map boundary. Distributions of marine fishes are shown in adjacent Arctic seas...


map background search result map search result map Marine Arctic polygon distribution of White Sea Eelpout (Lycodes marisalbi) Knipowitsch, 1906 Apatite and zircon fission track data from the western Brooks Range of Arctic Alaska Apatite and zircon fission track data from the western Brooks Range of Arctic Alaska Marine Arctic polygon distribution of White Sea Eelpout (Lycodes marisalbi) Knipowitsch, 1906