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How well seabirds compensate for variability in prey abundance and composition near their breeding colonies influences their distribution and reproductive success. We used tufted puffins (Fratercula cirrhata) as forage fish samplers to study marine food webs from the western Aleutian Islands (53°N, 173°E) to Kodiak Island (57°N, 153°W), Alaska, during August 2012–2014. Around each colony we obtained data on: environmental characteristics (sea surface temperature and salinity, seafloor depth and slope, tidal range, and chlorophyll-a), relative forage fish biomass (hydroacoustic backscatter), and seabird community composition and density at-sea. On colonies, we collected puffin chick-meals to characterize forage communities...
Categories: Publication; Types: Citation; Tags: Marine Biology
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Radiotelemetry methods were used to examine the demographic characteristics of sea otters inhabiting the leading edge of an expanding population on Kodiak Island, Alaska. Fifteen male and 30 female sea otters were instrumented and followed from 1986 to 1990. Twenty-one percent of females were sexually mature (had pupped) at age 2, 57% by age 3, 88% by age 4, and 100% by age 5. Fifteen females produced 26 pups, an overall reproduction rate of 94% for mature females. The reproduction rate was 17, 45, 66, and 100% for 2-, 3-, 4-, and 5-year-olds, respectively. Eighty-five percent of observed pups survived to weaning (120 days), and the percentage of pups weaned ranged from 34% for pups of 2-year-olds to 100% for pups...
Categories: Publication; Types: Citation; Tags: Canadian Journal of Zoology
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The Kittlitz's Murrelet Brachyramphus brevirostris is adapted for life in glacial-marine ecosystems, being concentrated in the belt of glaciated fjords in the northern Gulf of Alaska from Glacier Bay to Cook Inlet. Most of the remaining birds are scattered along coasts of the Alaska Peninsula and Aleutian Islands, where they reside in protected bays and inlets, often in proximity to remnant glaciers or recently deglaciated landscapes. We summarize existing information on Kittlitz's Murrelet in this mainly unglaciated region, extending from Kodiak Island in the east to the Near Islands in the west. From recent surveys, we estimated that ~2400 Kittlitz's Murrelets were found in several large embayments along the Alaska...
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The Arctic Coastal Plain of northern Alaska is a complex landscape of lakes, streams, and wetlands scattered across low relief tundra that is underlain by permafrost. This region of the Arctic has experienced a warming trend over the past three decades, leading to thawing of on-shore permafrost and the disappearance of sea ice at an unprecedented rate. The loss of sea ice has increased ocean wave action, leading to higher rates of erosion and salt water inundation of coastal habitats. Warming temperatures also have advanced the overall phenology of the region, including earlier snowmelt, lake ice thaw, and plant growth. As a result, many migratory species now arrive in the Arctic several days earlier in spring than...
Categories: Publication; Types: Citation; Tags: Fact Sheet
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Interactions between commercial fisheries and seabirds in the northern Pacific Ocean are increasing with rising consumption of fishery products. As fishing expands into remote areas previously not fished, additional populations of seabirds may be affected. Some interactions such as introduction of fish processing wastes into the environment may be beneficial for seabirds, while others such as competition for fish prey and incidental take by fishing nets may have negatively affected seabird populations.
Categories: Publication; Types: Citation
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We used a modeling framework and a recent ecological land classification and land cover map to predict how ecosystems and wildlife habitat in northwest Alaska might change in response to increasing temperature. Our results suggest modest increases in forest and tall shrub ecotypes in Northwest Alaska by the end of this century thereby increasing habitat for forest-dwelling and shrub-using birds and mammals. Conversely, we predict declines in several more open low shrub, tussock, and meadow ecotypes favored by many waterbird, shorebird, and small mammal species.
Categories: Publication; Types: Citation; Tags: Alaska Park Science
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Surveys of sea otters (Enhydra lutris) conducted before, immediately after, or at the time of the TA^ Exxon Valdez oil spill were used to guide otter capture efforts and assess the immediate effects of the spill. Shoreline counts (by boat) of sea otters in Prince William Sound in 1984 suggested that a minimum of 4,500 sea otters inhabited nearshore waters of Prince William Sound. Areas of highest density within the western portion of Prince William Sound included the Bainbridge Island area, Montague Island, Green Island, and Port Wells. About 1,330 sea otters were counted from helicopters along the coast of the Kenai Peninsula. Highest densities of sea otters were found along the western end of the Kenai Peninsula....
Categories: Publication; Types: Citation; Tags: Biological Report
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In this chapter we review existing knowledge of marine birds in the Gulf of Alaska. Three estuarine systems in the Gulf provide critical habitat for migratory shorebirds and waterfowl: 1) the Stikine River Delta, 2) Cook Inlet, and 3) the Copper River Delta. Over 20 million waterbirds are estimated to use the latter system during spring migration. Western sandpipers, dunlin, and northern pintails numerically dominate this migration. Breeding populations of shorebirds and waterfowl in the Gulf are small compared with those elsewhere in Alaska. Of those Gulf regions suitable for nesting waterfowl and shorebirds, the Copper River Delta is the most important. Species diversity and the number of shorebirds wintering...
Categories: Publication; Types: Citation
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During implantation of radiotelemetry devices in sea otters (Enhydra lutris) at the Seward Otter Rehabilitation Center, surgical team members noted ulcers in the oral cavity of each of five animals examined. Oral lesions were identified in 25 of 27 otters examined at the center. Histological evaluation of the lesions revealed focal areas of mucosal epithelial necrosis with associated intranuclear viral inclusion bodies. A herpes-like virus was subsequently identified ultrastructurally. The concern of releasing a virus of unknown origin and virulence into a naive wild otter population prompted management decisions restricting the movement of otters and jeopardizing the scheduled release of the otters on 27 July 1989....
Categories: Publication; Types: Citation; Tags: Biological Report
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The Aleutian Islands are situated on the northern edge of the so-called “Pacific Ring of Fire,” a 40,000-km-long horseshoe-shaped assemblage of continental landmasses and islands bordering the Pacific Ocean basin that contains many of the world's active and dormant volcanoes. Schaefer et al. (2009) listed 27 historically active volcanoes in the Aleutian Islands, of which nine have had at least one major eruptive event since 1990. Volcanic eruptions are often significant natural disturbances, and ecosystem responses to volcanic eruptions may vary markedly with eruption style (effusive versus explosive), frequency, and magnitude of the eruption as well as isolation of the disturbed sites from potential colonizing...
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Nearly 900 sea otter (Enhydra lutris) carcasses were recovered in or adjacent to coastal areas affected by the T/V Exxon Valdez oil spill. The time of carcass recovery and the condition of carcasses indicate that most oil spill-induced mortality occurred early in the response period. In fact, by 19 May about 70% of the carcasses had been found. The majority of the carcasses (56%) were from Prince William Sound, suggesting that mortality was more acute there than in other geographic areas. Examination of the recovered carcasses indicated that more adult female sea otters were killed by the oil in Prince William Sound and along the Kenai Peninsula than other sex and age cohorts, reflecting greater abundance of adult...
Categories: Publication; Types: Citation; Tags: Biological Report
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Existing knowledge on high-seas and coastal gillnet fisheries known to kill seabirds in the North Pacific is summarized. Recent estimates suggest that high-seas gillnet fisheries may have taken more than 500,000 seabirds in 1990. The majority of birds taken in those fisheries were Sooty Puffinus griseus or Short-tailed P. tenuirostris shearwaters. A recent analysis of impacts of those fisheries suggests that both shearwater populations may be declining slightly, although overall populations remain large. Impacts on seabirds of gillnet fishing in coastal waters are poorly known, except in California. Incidental mortality of seabirds in coastal gillnet fisheries may be adding additional stress to populations already...
Categories: Publication; Types: Citation
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ound, Alaska, spilling approximately 11 million barrels of crude oil. Oil wasdeposited on beaches nearly 700 km from the spill site (Galt and Payton 1990,Piatt et al. 1990), affecting thousands of hectares of sea otter(Enhydra lutris)habitat. Two of the principal limitations in determining the initial effects of theExxon Valdez oil spill on sea otter populations were a lack of recent populationdata, and a lack of information on the proportion of the total number of seaotters killed by the spill that were actually recovered.ound, Alaska, spilling approximately 11 million barrels of crude oil. Oil wasdeposited on beaches...
Categories: Publication; Types: Citation; Tags: Marine Mammal Science
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During July 16–18, 2013, low-level photography flights were conducted (with a Cessna 185 with floats and a Cessna 206 with tundra tires) over the five administrative units of the National Park Service Arctic Network (Bering Land Bridge National Preserve, Cape Krusenstern National Monument, Gates of the Arctic National Park and Preserve, Kobuk Valley National Park, and Noatak National Preserve) and the U.S. Fish and Wildlife Service’s Selawik National Wildlife Refuge in northwest Alaska, to provide images of current conditions and prevalence of land-cover types as a baseline for measuring future change, and to complement the existing grid-based sample photography of the region. Total flight time was 17 hours, 46...
Categories: Publication; Types: Citation; Tags: Data Series
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Mortality rates of seabirds in the Japanese land-based drift gillnet fishery for salmon were assessed from 413 gillnet sets made by Japanese research vessels in offshore areas used by the commercial fleet. Sixteen species of seabirds were recorded in nets. Shearwaters, primarily Short-tailed Shearwaters (Puffinus tenuirostris), and to a lesser extent Sooty Shearwaters (P. griseus), predominated in the catches, followed by lesser numbers of Tufted Puffins (Fratercula cirrhata) and Thick-billed Murres (Uria lomvia). Catch-rates of seabirds varied by oceanographic zone, with most being caught in oceanic waters north of the Subarctic Front. Approximately 151,000 seabirds were killed in the offshore component of the...
Categories: Publication; Types: Citation; Tags: The Condor
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Arctic and boreal ecosystems provide important breeding habitat for more than half of North America’s migratory birds as well as many resident species. Northern landscapes are projected to experience more pronounced climate-related changes in habitat than most other regions. These changes include increases in shrub growth, conversion of tundra to forest, alteration of wetlands, shifts in species’ composition, and changes in the frequency and scale of fires and insect outbreaks. Changing habitat conditions, in turn, may have significant effects on the distribution and abundance of wildlife in these critical northern ecosystems. The U.S. Geological Survey (USGS) is conducting studies in the Boreal–Arctic transition...
Categories: Publication; Types: Citation; Tags: Fact Sheet
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We project the effects of transitional changes among 60 vegetation and other land cover types (“ecotypes”) in northwest Alaska over the 21st century on habitats of 162 bird and 39 mammal species known or expected to occur regularly in the region. This analysis, encompassing a broad suite of arctic and boreal wildlife species, entailed building wildlife-habitat matrices denoting levels of use of each ecotype by each species, and projecting habitat changes under historic and expected accelerated future rates of change from increasing mean annual air temperature based on the average of 5 global climate models under the A1B emissions scenario, and from potential influence of a set of 23 biophysical drivers. Under historic...
Categories: Publication; Types: Citation; Tags: Climatic Change
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According to the U.S. Fish and Wildlife Services’ (USFWS) Response Plan for sea otters (USFWS, in preparation), in the event of an oil spill, the decision to release sea otters from rehabilitation centers following treatment will be linked to the decision on whether to capture sea otters for treatment. Assuming a scenario similar to the Exxon Valdez oil spill (EVOS), once the decision to capture sea otters is made, the ultimate goal is to return as many sea otters to the wild as possible, even though the rescue may not be expected to produce results significant at the population level. The decision by the USFWS to proceed with capture, rehabilitation, and release will be made on a case-by-case basis (USFWS, in preparation)....
Categories: Publication; Types: Citation
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Ecosystems and their wildlife communities are not static; they change and evolve over time due to numerous intrinsic and extrinsic factors. A period of rapid change is occurring in the Arctic for which our current understanding of potential ecosystem and wildlife responses is limited. Changes to the physical environment include warming temperatures, diminishing sea ice, increasing coastal erosion, deteriorating permafrost, and changing water regimes. These changes influence biological communities and the ways in which human communities interact with them. Through the new initiative Changing Arctic Ecosystems (CAE) the U.S. Geological Survey (USGS) strives to (1) understand the potential suite of wildlife population...
Categories: Publication; Types: Citation; Tags: Fact Sheet


map background search result map search result map Changing Arctic ecosystems - measuring and forecasting the response of Alaska's terrestrial ecosystem to a warming climate Changing Arctic ecosystems--the role of ecosystem changes across the Boreal-Arctic transition zone on the distribution and abundance of wildlife populations Predicting the effects of climate change on ecosystems and wildlife habitat in northwest Alaska: results from the WildCast project Ice, climate change and wildlife research in Alaska Low-altitude photographic transects of the Arctic Network of National Park Units and Selawik National Wildlife Refuge, Alaska, July 2013 Predicting the effects of climate change on ecosystems and wildlife habitat in northwest Alaska: results from the WildCast project Low-altitude photographic transects of the Arctic Network of National Park Units and Selawik National Wildlife Refuge, Alaska, July 2013 Changing Arctic ecosystems - measuring and forecasting the response of Alaska's terrestrial ecosystem to a warming climate Changing Arctic ecosystems--the role of ecosystem changes across the Boreal-Arctic transition zone on the distribution and abundance of wildlife populations Ice, climate change and wildlife research in Alaska