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1
Suydam, Robert S., D. Lynne Dickson, Janey B. Fadely, and Lori T. Quakenbush. "Population Declines of King and Common Eiders of the Beaufort Sea." Condor 102, no. 1 (February 1, 2000): 219–22. http://dx.doi.org/10.1093/condor/102.1.219.
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Abstract King (Somateria spectabilis) and Common Eiders (S. mollissima v-nigra) wintering off western North America migrate past Point Barrow, Alaska and across the Beaufort Sea to nest in northern Alaska and northwestern Canada. Migration counts were conducted by various researchers at Point Barrow during 1953, 1970, 1976, 1987, 1994, and 1996. We examined population trends by standardizing the analysis of the migration counts in all years. Based on this standardized procedure, the King Eider population appeared to remain stable between 1953 and 1976 but declined by 56% (or 3.9% year−1) from approximately 802,556 birds in 1976 to about 350,835 in 1996. The Common Eider population declined by 53% (or 3.6% year−1) from approximately 156,081 birds in 1976 to about 72,606 in 1996. Reasons for the declines are unknown.
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Hupp, Jerry W., Joel A. Schmutz, and Craig R. Ely. "The Annual Migration Cycle of Emperor Geese in Western Alaska." ARCTIC 61, no. 1 (March 1, 2009): 23. http://dx.doi.org/10.14430/arctic4.
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Most emperor geese (Chen canagica) nest in a narrow coastal region of the Yukon-Kuskokwim Delta (YKD) in western Alaska, but their winter distribution extends more than 3000 km from Kodiak Island, Alaska, to the Commander Islands, Russia. We marked 53 adult female emperor geese with satellite transmitters on the YKD in 1999, 2002, and 2003 to examine whether chronology of migration or use of seasonal habitats differed among birds that wintered in different regions. Females that migrated relatively short distances (650–1010 km) between the YKD and winter sites on the south side of the Alaska Peninsula bypassed autumn staging areas on the Bering Sea coast of the Alaska Peninsula or used them for shorter periods (mean = 57 days) than birds that made longer migrations (1600–2640 km) to the western Aleutian Islands (mean = 97 days). Alaska Peninsula migrants spent more days at winter sites (mean = 172 days, 95% CI: 129–214 days) than western Aleutian Island migrants (mean = 91 days, 95% CI: 83–99 days). Birds that migrated 930–1610 km to the eastern Aleutian Islands spent intermediate intervals at fall staging (mean = 77 days) and wintering areas (mean = 108 days, 95% CI: 95–119 days). Return dates to the YKD did not differ among birds that wintered in different regions. Coastal staging areas on the Alaska Peninsula may be especially important in autumn to prepare Aleutian migrants physiologically for long-distance migration to winter sites, and in spring to enable emperor geese that migrate different distances to reach comparable levels of condition before nesting.
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Riedman, Marianne L., and James A. Estes. "Predation on seabirds by sea otters." Canadian Journal of Zoology 66, no. 6 (June 1, 1988): 1396–402. http://dx.doi.org/10.1139/z88-205.
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Although rarely reported in the past, predation by sea otters (Enhydra lutris) on seabirds has been observed more frequently in the last decade. A total of 23 incidents of definite or probable predation on seabirds have been observed in California (20) and in Alaska at Amchitka Island (3). In California, the most commonly eaten species were western grebes, although cormorants, gulls, common loons, and surf scoters were also consumed. All cases of seabird predation in California have occurred in the northern part of the sea otter's range in three locations: Point Lobos, Stillwater Cove, and the Monterey harbor area. When sex could be determined, most of the otters observed feeding on seabirds were adult males. At one site, it appeared that the same individual repeatedly captured birds. Predation on seabirds is indicative of the sea otter's ability to learn new and innovative foraging tactics, and is consistent with a high degree of individual variation in diet observed among sea otters in Monterey. Sea otters initially capture birds by diving and grabbing them from underwater while the bird rests on the surface, in a manner similar to that employed by coastal river otters to capture seabirds. When mink, freshwater-inhabiting otters, and sea otters are compared, a graded reduction in the tendency to eat birds appears to occur in the more aquatic mustelids, with the relative importance of birds in the diet being greatest in mink and least in sea otters.
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Divoky, G. J., D. C. Douglas, and I. J. Stenhouse. "Arctic sea ice a major determinant in Mandt's black guillemot movement and distribution during non-breeding season." Biology Letters 12, no. 9 (September 2016): 20160275. http://dx.doi.org/10.1098/rsbl.2016.0275.
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Mandt's black guillemot ( Cepphus grylle mandtii ) is one of the few seabirds associated in all seasons with Arctic sea ice, a habitat that is changing rapidly. Recent decreases in summer ice have reduced breeding success and colony size of this species in Arctic Alaska. Little is known about the species' movements and distribution during the nine month non-breeding period (September–May), when changes in sea ice extent and composition are also occurring and predicted to continue. To examine bird movements and the seasonal role of sea ice to non-breeding Mandt's black guillemots, we deployed and recovered ( n = 45) geolocators on individuals at a breeding colony in Arctic Alaska during 2011–2015. Black guillemots moved north to the marginal ice zone (MIZ) in the Beaufort and Chukchi seas immediately after breeding, moved south to the Bering Sea during freeze-up in December, and wintered in the Bering Sea January–April. Most birds occupied the MIZ in regions averaging 30–60% sea ice concentration, with little seasonal variation. Birds regularly roosted on ice in all seasons averaging 5 h d −1 , primarily at night. By using the MIZ, with its roosting opportunities and associated prey, black guillemots can remain in the Arctic during winter when littoral waters are completely covered by ice.
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Hutmacher, W. J., and R. Rodriguez. "Challenges Associated with Oil Spill Response in Remote Regions of Western Alaska." International Oil Spill Conference Proceedings 2001, no. 1 (March 1, 2001): 209–11. http://dx.doi.org/10.7901/2169-3358-2001-1-209.
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ABSTRACT Western Alaska is, to say the least, remote. The area is vast, unforgiving at times, and notorious for offering rugged coastlines, severe weather conditions, and home to numerous species of birds, marine and terrestrial mammals, and fish. To get an understanding of the size of this state, Alaska spans about 20 degrees of latitude (1,200 miles) and more than 45 degrees of longitude (2,700 miles). The coastline area runs from Cape Puget in the Gulf of Alaska to the Alaska Peninsula, to the Aleutian Islands thence north to Barrow including, the Bering and Chukchi Seas, and thence east through the Beaufort Sea to the U.S.-Canada border. Traveling north to south, the region is classified as arctic, subarctic, or marine coastal. This paper will discuss the challenges faced by federal, state, and local agencies, and responders while responding to vessel casualties in the remote regions of Alaska. The geographic area of the state this paper will focus on is known as Western Alaska and is composed of the Alaska Peninsula, Aleutian Islands, the islands of Bristol Bay, and Pribilof Islands. The bodies of water surrounding Western Alaska are the Gulf of Alaska, North Pacific Ocean, Bristol Bay, and Bering Sea.
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Savage, Susan E., T. Lee Tibbitts, Kristin A. Sesser, and Robb A. S. Kaler. "Inventory of Lowland-Breeding Birds on the Alaska Peninsula." Journal of Fish and Wildlife Management 9, no. 2 (August 14, 2018): 637–58. http://dx.doi.org/10.3996/082017-jfwm-070.
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Abstract We conducted the first systematic inventory of birds in the lowlands (areas ≤100 m above sea level) of the Alaska Peninsula during summers of 2004–2007 to determine their breeding distributions and habitat associations in this remote region. Using a stratified random survey design, we allocated sample plots by elevation and land cover with a preference for wetland cover types used by shorebirds, a group of particular interest to land managers. We surveyed birds during 10-min counts at 792 points across 52, 5 km × 5 km sample plots distributed from south of the Naknek River (58.70°N,157.00°W) to north of Port Moller (56.00°N,160.52°W). We detected 95 bird species including 19 species of shorebirds and 34 species (36% of total) considered at the time to be of conservation concern for the land managers in the region. The most numerous shorebirds on point counts were dunlin Calidris alpina, short-billed dowitcher Limnodromus griseus, and Wilson's snipe Gallinago delicata. We found the breeding-season endemic marbled godwit Limosa fedoa beringiae at 20 plots within a 3,000-km2 area from north of Ugashik Bay to just north of Port Heiden and east to the headwaters of the Dog Salmon and Ugashik rivers. The most abundant passerines on point counts were American tree sparrow Spizelloides arborea, Lapland longspur Calcarius lapponicus, and savannah sparrow Passerculus sandwichensis. Sandhill crane Antigone canadensis, glaucous-winged gull Larus glaucescens, and greater scaup Aythya marila were also relatively abundant. We categorized habitat associations for 30 common species and found that lowland herbaceous vegetation supported wetland-focused species including sandhill crane, marbled godwit, short-billed dowitcher, and dunlin; whereas, dwarf shrub-ericaceous vegetation supported tundra-associated species such as willow ptarmigan Lagopus lagopus, rock sandpiper Calidris ptilocnemis, and American pipit Anthus rubescens. Tall shrub vegetation was important to several species of warblers and sparrows, as well as one species of shorebird (greater yellowlegs Tringa melanoleuca). We found that point counts augmented with incidental observations provided an almost complete inventory of lowland-breeding species on the study area. These data form a baseline to monitor any future changes in bird distribution and abundance on the Alaska Peninsula.
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Harvell, C. D., D. Montecino-Latorre, J. M. Caldwell, J. M. Burt, K. Bosley, A. Keller, S. F. Heron, et al. "Disease epidemic and a marine heat wave are associated with the continental-scale collapse of a pivotal predator (Pycnopodia helianthoides)." Science Advances 5, no. 1 (January 2019): eaau7042. http://dx.doi.org/10.1126/sciadv.aau7042.
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Multihost infectious disease outbreaks have endangered wildlife, causing extinction of frogs and endemic birds, and widespread declines of bats, corals, and abalone. Since 2013, a sea star wasting disease has affected >20 sea star species from Mexico to Alaska. The common, predatory sunflower star (Pycnopodia helianthoides), shown to be highly susceptible to sea star wasting disease, has been extirpated across most of its range. Diver surveys conducted in shallow nearshore waters (n= 10,956; 2006–2017) from California to Alaska and deep offshore (55 to 1280 m) trawl surveys from California to Washington (n= 8968; 2004–2016) reveal 80 to 100% declines across a ~3000-km range. Furthermore, timing of peak declines in nearshore waters coincided with anomalously warm sea surface temperatures. The rapid, widespread decline of this pivotal subtidal predator threatens its persistence and may have large ecosystem-level consequences.
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Bergmann, Pamela, and Nick Russo. "JOINT CANADA/UNITED STATES WILDLIFE RESPONSE PLANNING: DIXON ENTRANCE." International Oil Spill Conference Proceedings 2001, no. 2 (March 1, 2001): 1327–32. http://dx.doi.org/10.7901/2169-3358-2001-2-1327.
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ABSTRACT Neither wildlife nor oil spills acknowledge international boundaries. Both migratory birds and marine mammals move freely between Alaska in the United States and British Columbia in Canada, in the international boundary area known as Dixon Entrance in the North Pacific Ocean. An oil spill on one side of the border may be carried by winds and/or currents into the waters of the adjacent country. Recognition of these facts resulted in the development of the Canada/United States Joint Marine Pollution Contingency Plan, which was signed by the Canadian Coast Guard (CCG) and U.S. Coast Guard (USCG) in 1974. Annexes were subsequently prepared for five transboundary areas, including Dixon Entrance. Following the promulgation of these annexes, joint exercises have been held to enhance annex implementation. In September 1999, at the request of the USCG and CCG, the U.S. Department of the Interior, Alaska Office of Environmental Policy and Compliance (DOI-OEPC) took the lead in organizing and chairing a workshop to discuss issues associated with wildlife response activities for oil spills that cross the Canada/United States border in Dixon Entrance. The workshop was held in Prince Rupert, British Columbia as part of a 4-day joint meeting. Workshop participants included representatives from key U.S. federal and Alaska State wildlife resource agencies, Canadian federal wildlife resource agencies, oil spill cooperatives for Southeast Alaska and British Columbia, and the USCG. Wildlife resource agency representatives participating in the workshop reached consensus that the goal of wildlife protection is to make decisions based on what is best for the wildlife resources and then to determine how the goal can be accomplished within the constraints of each countries regulatory process. Agreement was reached to form a Canada/United States working group to develop a joint wildlife response plan. The plan, which will focus on migratory birds and sea otters, will address issues associated with the removal of dead oiled wildlife from the environment, hazing of unoiled wildlife, preemptive capture of sea otters, and capture and treatment of oiled migratory birds and sea otters. A draft plan will be developed prior to a September 2000, Canada/U.S. Dixon Entrance (CANUSDIX) joint meeting, which will be held in Ketchikan, Alaska.
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Petersen, Margaret R., and Paul L. Flint. "Population Structure of Pacific Common Eiders Breeding in Alaska." Condor 104, no. 4 (November 1, 2002): 780–87. http://dx.doi.org/10.1093/condor/104.4.780.
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Abstract We used satellite telemetry to study the migration routes and wintering areas of two allopatric breeding populations of Pacific Common Eiders (Somateria mollissimav-nigrum) in Alaska: the Yukon-Kuskokwim Delta, and the western Beaufort Sea coast. Only 6% (2 of 36) of females wintered within the wintering area of the other breeding population. Both breeding populations wintered in the closest available ice-free habitat, perhaps to minimize migratory distance. Two Beaufort Sea females wintered in areas used by Yukon-Kuskokwim Delta females, implying potential gene flow among breeding areas. Yet, we conclude that these two populations are largely geographically isolated throughout the annual cycle and the environmental factors influencing survival and reproduction likely differ between these groups of birds. Thus, regardless of the potential gene flow among breeding populations, we suggest that birds from these two breeding areas should be managed as separate populations. Estructura Poblacional Reproductiva de Somateria mollissimav-nigrum en Alaska Resumen. Usamos telemetría satelital para estudiar las rutas de migración y áreas de invernada de dos poblaciones alopáticas reproductivas de Somateria mollissimav-nigrum en Alaska: la del Delta Yukon-Kuskokwim, y la de la costa oeste del Mar de Beaufort. Solo el 6% (2 de 36) de las hembras invernaron dentro del área de invernada de la otra población reproductiva. Las dos poblaciones invernaron en el hábitat libre de hielo más cercano, tal vez para minimizar la distancia de migración. Dos hembras del Mar de Beaufort invernaron en áreas usadas por hembras del Delta de Yukon-Kuskokwim, implicando un potencial flujo génico entre las áreas de reproducción. Sin embargo, concluimos que estas dos poblaciones están aisladas geográficamente a lo largo del ciclo anual y que los factores ambientales que afectan la supervivencia y reproducción son probablemente diferentes entre estos grupos de aves. Por lo tanto, a pesar del flujo génico potencial entre las poblaciones reproductivas, sugerimos que las aves de estas dos áreas de reproducción deben ser manejadas como poblaciones separadas.
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Guénette, Sylvie, Sheila JJ Heymans, Villy Christensen, and Andrew W. Trites. "Ecosystem models show combined effects of fishing, predation, competition, and ocean productivity on Steller sea lions (Eumetopias jubatus) in Alaska." Canadian Journal of Fisheries and Aquatic Sciences 63, no. 11 (November 1, 2006): 2495–517. http://dx.doi.org/10.1139/f06-136.
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Steller sea lions (Eumetopias jubatus) increased in the eastern portion of their range while declining in the Gulf of Alaska and Aleutian Islands from the late 1970s to late 1990s. We constructed ecosystem models of the central and western Aleutians and of southeast Alaska to simultaneously evaluate four hypotheses explaining sea lion dynamics: killer whale (Orcinus orca) predation, ocean productivity, fisheries, and competition with other species. Comparisons of model predictions with historical time series data indicate that all four factors likely contributed to the trends observed in sea lion numbers in both ecosystems. Changes in ocean productivity conveyed by the Pacific Decadal Oscillation influenced the abundance trajectory of several species. Fishing could have affected the ecosystem structure by influencing the abundance of Atka mackerel (Pleurogrammus monopterygius) in the Aleutians and Pacific herring (Clupea pallasii) in southeast Alaska. Pacific halibut (Hippoglossus stenolepis) in the Aleutians and arrowtooth flounder (Atheresthes stomias) in southeast Alaska appear to impede sea lion population growth through competitive interactions. Predation by killer whales was important when sea lions were less abundant in the 1990s in the Aleutians and in the 1960s in Southeast Alaska, but appear to have little effect when sea lion numbers were high.
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Rojek, Nora A., and Jeffrey C. Williams. "Present-Day Assemblage of Birds and Mammals in the Islands of Four Mountains, Eastern Aleutians, Alaska." Quaternary Research 91, no. 03 (June 11, 2018): 1059–74. http://dx.doi.org/10.1017/qua.2018.36.
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AbstractWe compiled present-day observations and survey data of the avian and mammal fauna in the Islands of Four Mountains, Alaska, which primarily consist of marine-adapted species, to provide insight into the prehistoric fauna found in the archaeological record. We documented 63 bird species, mainly seabirds (67%). The majority (71%) of the estimated number of breeding birds are ledge nesters, predominately murres, and most (68%) spend the majority of their lives in the offshore environment. We lack good estimates for burrow and crevice nesters, which were impacted by and are still recovering from a period of arctic fox farming in the twentieth century. Marine mammals, predominately Steller sea lion, harbor seal, and sea otter, primarily use accessible land as haul-outs and are found in low numbers compared with the rest of the Aleutians. Red fox, the only land mammal, presently only reside on Chuginadak Island. While the present-day fauna is similar to the fauna recorded in the archaeological record, we found no indication of nesting by ancient murrelets and northern fulmars in the Island of Four Mountains, whereas both species were present in midden sites on Carlisle and Chuginadak Islands, with the possibility of prehistoric breeding colonies on Carlisle Island.
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Hatch, Scott A., Paul M. Meyers, Danial M. Mulcahy, and David C. Douglas. "Seasonal Movements and Pelagic Habitat Use of Murres and Puffins Determined by Satellite Telemetry." Condor 102, no. 1 (February 1, 2000): 145–54. http://dx.doi.org/10.1093/condor/102.1.145.
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AbstractWe tracked the movements of Common Murres (Uria aalge), Thick-billed Murres (U. lomvia), and Tufted Puffins (Fratercula cirrhata) using surgically implanted satellite transmitters. From 1994–1996, we tagged 53 birds from two colonies in the Gulf of Alaska (Middleton Island and Barren Islands) and two colonies in the Chukchi Sea (Cape Thompson and Cape Lisburne). Murres and puffins ranged 100 km or farther from all colonies in summer, but most instrumented birds had abandoned breeding attempts and their movements likely differed from those of actively breeding birds. However, murres whose movements in the breeding period suggested they still had chicks to feed foraged repeatedly at distances of 50–80 km from the Chukchi colonies in 1995. We detected no differences in the foraging patterns of males and females during the breeding season, nor between Thick-billed and Common Murres from mixed colonies. Upon chick departure from the northern colonies, male murres—some believed to be tending their flightless young—drifted with prevailing currents toward Siberia, whereas most females flew directly south toward the Bering Sea. Murres from Cape Thompson and Cape Lisburne shared a common wintering area in the southeastern Bering Sea in 1995, and birds from Cape Lisburne returned to the same area in the winter of 1996. We conclude that differences in foraging conditions during summer rather than differential mortality rates in winter account for contrasting population trends previously documented in those two colonies.
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Hatch, Scott A., Verena A. Gill, and Daniel M. Mulcahy. "Individual and colony-specific wintering areas of Pacific northern fulmars (Fulmarus glacialis)." Canadian Journal of Fisheries and Aquatic Sciences 67, no. 2 (February 2010): 386–400. http://dx.doi.org/10.1139/f09-184.
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Seabird mortality associated with longline fishing in the eastern Bering Sea occurs mainly from September to May, with northern fulmars ( Fulmarus glacialis ) comprising the majority (60%) of the bycatch. Along the west coast of North America, winter dieoffs of fulmars may be increasing in frequency and magnitude, the most severe on record being a wreck that peaked in October–November 2003. We deployed satellite transmitters on fulmars from the four main Alaska colonies and tracked individuals for up to 2 years. Fulmars from Hall Island (northern Bering Sea) moved to Russian coastal waters after breeding, while Pribilof Island fulmars (southeastern Bering Sea) remained relatively sedentary year-round. Birds from Chagulak Island (eastern Aleutians) preferred passes between the Aleutian Islands in winter or foraged widely over deep waters of the central Bering Sea and North Pacific. Fulmars from the Semidi Islands (western Gulf of Alaska) migrated directly to waters of the California Current. Individuals from St. George Island (Pribilofs) and Chagulak were consistent in the places that they visited in two successive winters. The Pribilof Islands population is most affected by winter longlining for groundfish, whereas the Semidi Islands colony sustains most of the natural mortality that occurs off Washington, Oregon, and California.
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Amundson, Courtney L., Colleen M. Handel, Daniel R. Ruthrauff, T. Lee Tibbitts, and Robert E. Gill. "Montane-breeding Bird Distribution and Abundance Across National Parks of Southwestern Alaska." Journal of Fish and Wildlife Management 9, no. 1 (March 22, 2018): 180–207. http://dx.doi.org/10.3996/062017-jfwm-050.
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Abstract Between 2004 and 2008, biologists conducted an inventory of breeding birds during May–June primarily in montane areas (>100 m above sea level) of Aniakchak National Monument and Preserve (Aniakchak NMP), Katmai National Park and Preserve (Katmai NPP), and Lake Clark National Park and Preserve (Lake Clark NPP) in southwestern Alaska. Observers conducted 1,021 point counts along 169 transects within 63 10-km × 10-km plots that were randomly selected and stratified by ecological subsection. We created hierarchical N-mixture models to estimate detection probability and abundance for 15 species, including 12 passerines, 2 galliforms, and 1 shorebird. We first modeled detection probability relative to observer, date within season, and proportion of dense vegetation cover around the point, then modeled abundance as a function of land cover composition (proportion of seven coarse-scale land cover types) within 300 m of the survey point. Land cover relationships varied widely among species but most showed selection for low to tall shrubs (0.2–5 m tall) and an avoidance of alpine and dwarf shrub–herbaceous cover types. After adjusting for species not observed, we estimated a minimum of 107 ± 9 species bred in the areas surveyed within the three parks combined. Species richness was negatively associated with elevation and associated land cover types. At comparable levels of survey effort (n = 721 birds detected), species richness was greatest in Lake Clark NPP (75 ± 12 species), lowest in Aniakchak NMP (45 ± 6 species), and intermediate at Katmai NPP (59 ± 10 species). Species richness was similar at equivalent survey effort (n = 973 birds detected) within the Lime Hills, Alaska Range, and Alaska Peninsula ecoregions (68 ± 8; 79 ± 11; 67 ± 11, respectively). Species composition was similar across all three parks and across the three major ecoregions (Alaska Range, Alaska Peninsula, Lime Hills) that encompass them. Our results provide baseline estimates of relative abundance and models of abundance and species richness relative to land cover that can be used to assess future changes in avian distribution. Additionally, these subarctic montane parks may serve as signals of landscape change and barometers for the assessment of population and distributional changes as a result of warming temperatures and changing precipitation patterns.
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Drew, Gary S., Donald E. Dragoo, Martin Renner, and John F. Piatt. "At-sea Observations of Marine Birds and Their Habitats before and after the 2008 Eruption of Kasatochi Volcano, Alaska." Arctic, Antarctic, and Alpine Research 42, no. 3 (August 2010): 325–34. http://dx.doi.org/10.1657/1938-4246-42.3.325.
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Drummond, Brie A., Rachael A. Orben, Aaron M. Christ, Abram B. Fleishman, Heather M. Renner, Nora A. Rojek, and Marc D. Romano. "Comparing non-breeding distribution and behavior of red-legged kittiwakes from two geographically distant colonies." PLOS ONE 16, no. 7 (July 16, 2021): e0254686. http://dx.doi.org/10.1371/journal.pone.0254686.
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Knowledge of non-breeding distributions is a crucial component to seabird conservation, as conditions during the non-breeding period can play an important role in regulating seabird populations. Specifically, if seabirds from different colonies share the same wintering grounds, conditions in that shared region could have a widespread impact on multiple breeding populations. Red-legged kittiwakes (Rissa brevirostris) are endemic to the Bering Sea and may be especially susceptible to effects of climate change due to a restricted breeding range, small population size, and specialized diet. To examine whether red-legged kittiwakes from different breeding colonies overlapped in winter distribution and activity patterns, we used geolocation loggers to simultaneously track individuals from the two largest red-legged kittiwake breeding colonies in Alaska (separated by over 1000 km) during two consecutive non-breeding periods. We found that non-breeding activity patterns were generally similar between birds originating from the two colonies, but birds employed different migratory strategies during the early winter. Kittiwakes from Buldir Island in the western Aleutian Islands left the colony in September and immediately headed west, spending October through December around the Sea of Okhotsk and the Kuril Islands. In contrast, birds from St. George Island in the Pribilof Islands remained in the eastern Bering Sea or around the eastern Aleutian Islands for a couple months before traveling farther west. During late winter however, from January through March, birds from both colonies converged south of Kamchatka and east of the Kuril Islands over the Kuril-Kamchatka Trench and in the Western Subarctic Gyre before returning to their respective colonies in the spring. This late winter overlap in distributions along the Kuril-Kamchatka Trench suggests the region is a winter hotspot for red-legged kittiwakes and highlights the importance of this region for the global kittiwake population.
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Shelton, Andrew O., Douglas A. Woodby, Kyle Hebert, and Jon D. Witman. "Evaluating Age Determination and Spatial Patterns of Growth in Red Sea Urchins in Southeast Alaska." Transactions of the American Fisheries Society 135, no. 6 (November 2006): 1670–80. http://dx.doi.org/10.1577/t05-175.1.
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Hutchinson, Emily, Shannon Atkinson, and Kathy Burek Huntington. "Growth and sexual maturation in male northern sea otters (Enhydra lutris kenyoni) from Gustavus, Alaska." Journal of Mammalogy 96, no. 5 (July 13, 2015): 1045–54. http://dx.doi.org/10.1093/jmammal/gyv114.
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Pearson, Leslie A. "Public Perceptions on the Use of Oil Spill Response Methods in Alaskan Waters and the Level of Trust in Organizations to Prevent Oil Spills." International Oil Spill Conference Proceedings 2003, no. 1 (April 1, 2003): 349–52. http://dx.doi.org/10.7901/2169-3358-2003-1-349.
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ABSTRACT All of the cleanup methods available for responding to a marine oil spill in Alaska have operational limitations. In Prince William Sound and Cook Inlet, non-mechanical response methods such as the use of chemical dispersants or in situ burning can be requested as secondary cleanup options. This study identifies citizens’ concern and determines the preference of response methods and perceived effectiveness of each method. Environmental risks, values, and the level of trust residents in communities of Prince William Sound and Cook Inlet are also examined., A correlational research design was used to answer research questions with survey data collected by randomly sampling 1657 residents in fifteen communities of Prince William Sound and Cook Inlet. Of the 1657 surveys mailed a response rate of 41% was obtained. Descriptive and inferential statistical analyses were used to analyze the survey information. General descriptive statistical analysis was used to examine responses to each statement in the survey. Inferential statistical analysis was used to quantify the direction and strength of a relationship between variables., In general, 92% of the respondents support the use of mechanical recovery methods, 61% support the use of in situ burning and 45% chemical dispersants. The population recognizes burning as a means of removing large quantities of oil from the sea surface and the environmental risk of displacing pollutants into the atmosphere. Environmental concerns associated with the use of chemical dispersants are tied to seasonal abundance of and impact to marine organisms, amount of area and subsistence use and dependency on marine resources., The survey population's ecological priorities are commercial fishing, sea mammals and sea birds. The U.S. Coast Guard and Commercial Fishing Associations are held to the highest level of trust while the Alaska State Legislature and U.S. Congress received the lowest level of trust for ensuring Alaska waters remain oil free.
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Matta, Mary Elizabeth, and Donald R. Gunderson. "Age, growth, maturity, and mortality of the Alaska skate, Bathyraja parmifera, in the eastern Bering Sea." Environmental Biology of Fishes 80, no. 2-3 (February 14, 2007): 309–23. http://dx.doi.org/10.1007/s10641-007-9223-8.
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Suryan, Robert M., and Karen N. Fischer. "Stable isotope analysis and satellite tracking reveal interspecific resource partitioning of nonbreeding albatrosses off Alaska." Canadian Journal of Zoology 88, no. 3 (March 2010): 299–305. http://dx.doi.org/10.1139/z10-002.
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Albatrosses (Diomedeidae) are the most threatened family of birds globally. The three North Pacific species ( Phoebastria Reichenbach, 1853) are listed as either endangered or vulnerable, with the population of Short-tailed Albatross ( Phoebastria albatrus (Pallas, 1769)) less than 1% of its historical size. All North Pacific albatross species do not currently breed sympatrically, yet they do co-occur at-sea during the nonbreeding season. We incorporated stable isotope analysis with the first simultaneous satellite-tracking study of all three North Pacific albatross species while sympatric on summer (nonbreeding season) foraging grounds off Alaska. Carbon isotope ratios and tracking data identify differences in primary foraging domains of continental shelf and slope waters for Short-tailed Albatrosses and Black-footed Albatrosses ( Phoebastria nigripes (Audubon, 1839)) versus oceanic waters for Laysan Albatrosses ( Phoebastria immutabilis (Rothschild, 1893)). Short-tailed and Black-footed albatrosses also fed at higher trophic levels than Laysan Albatrosses. The relative trophic position of Black-footed and Laysan albatrosses, however, appears to differ between nonbreeding and breeding seasons. Spatial segregation also occurred at a broader geographic scale, with Short-tailed Albatrosses ranging more north into the Bering Sea than Black-footed Albatrosses, which ranged more to the southeast, and Laysan Albatrosses more to the southwest. Differences in carbon isotope ratios among North Pacific albatross species during the nonbreeding season likely reflect the relative proportion of neritic (more carbon enriched) versus oceanic (carbon depleted) derived nutrients, and possible differential use of fishery discards, rather than latitudinal differences in distribution.
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Flint, Paul L., John A. Reed, Deborah L. Lacroix, and Richard B. Lanctot. "Habitat Use and Foraging Patterns of Molting Male Long-tailed Ducks in Lagoons of the Central Beaufort Sea, Alaska." ARCTIC 69, no. 1 (March 1, 2016): 19. http://dx.doi.org/10.14430/arctic4544.
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From mid-July through September, 10 000 to 30 000 Long-tailed Ducks (<em>Clangula hyemalis</em>) use the lagoon systems of the central Beaufort Sea for remigial molt. Little is known about their foraging behavior and patterns of habitat use during this flightless period. We used radio transmitters to track male Long-tailed Ducks through the molt period from 2000 to 2002 in three lagoons: one adjacent to industrial oil field development and activity and two in areas without industrial activity. We found that an index to time spent foraging generally increased through the molt period. Foraging, habitat use, and home range size showed similar patterns, but those patterns were highly variable among lagoons and across years. Even with continuous daylight during the study period, birds tended to use offshore areas during the day for feeding and roosted in protected nearshore waters at night. We suspect that variability in behaviors associated with foraging, habitat use, and home range size are likely influenced by availability of invertebrate prey. Proximity to oil field activity did not appear to affect foraging behaviors of molting Long-tailed Ducks.
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Gill, Verena A., Scott A. Hatch, and Richard B. Lanctot. "Colonization, Population Growth, and Nesting Success of Black Oystercatchers Following a Seismic Uplift." Condor 106, no. 4 (November 1, 2004): 791–800. http://dx.doi.org/10.1093/condor/106.4.791.
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AbstractWe present data on the colonization of Middleton Island, Alaska, by Black Oystercatchers (Haematopus bachmani) following the creation of an extensive rocky intertidal zone after the Alaskan earthquake of 1964. The first pair of oystercatchers was detected in 1976, and it was another 5 years before the population increased to three pairs. Oystercatcher numbers increased steadily thereafter, with a population explosion occurring in the 1990s. By 2002, there were 171 territorial pairs on the island. The total number of birds increased from two in 1976 to 718 in 2002. Breeding-pair densities on Middleton Island are the highest recorded for any portion of Alaska, averaging more than 5 pairs per km of shoreline in 2002. Nesting success in 2001 and 2002 was greater (83% or more of the eggs laid hatched) than that reported for any other population of oystercatchers in Alaska or along the Pacific Coast. We attribute this exponential growth rate and exceptionally high reproductive success to the large area of available and suitable habitat, the low number of avian predators and the complete lack of mammalian predators, low rate of nest loss to high tides and storm surges, and a low level of human disturbance. We propose nominating Middleton Island as a regional Western Hemisphere Shorebird Reserve Network site because a high percentage of the world's and region's population of Black Oystercatchers resides there during the breeding season. Further, since Middleton Island may be the single most important site in Alaska for Black Oystercatchers, we suggest it be protected from future development.Colonización, Crecimiento Poblacional y Éxito de Nidada de Ostreros Negros Luego de un Movimiento SísmicoResumen. Presentamos datos sobre la colonización de la Isla Middleton, Alaska, por el Haematopus bachmani, luego de la creación de una extensa zona intermareal rocosa como resultado del terremoto ocurrido en 1964. La primera pareja de ostreros fue detectada en 1976, y pasaron otros 5 años antes de que la población aumente a tres parejas. Desde entonces los números de ostreros crecieron constantemente con una explosión de la población ocurrida en los 1990s. En 2002 había 171 parejas territoriales en la isla. El número total de individuos aumentó de dos en 1976 a 718 en 2002. Las densidades de parejas reproductivas en la Isla Middleton son las más altas registradas en cualquier lugar de Alaska, promediando más de 5 parejas por km de costa en 2002. El éxito de nidada en 2001 y 2002 fue mayor (83% o más de los huevos depositados eclosionaron) que el informado para cualquier otra población de ostreros de Alaska o de la costa Pacífica. Atribuimos esta tasa de crecimiento exponencial y el excepcional y alto éxito reproductivo, a la gran superficie con hábitat adecuado disponible, al bajo número de aves predadoras y a la completa ausencia de mamíferos predadores, a la baja tasa de perdida de nidos por mareas altas u oleaje por tormentas, y al bajo grado de disturbio humano. Proponemos la nominación de la Isla de Middleton como Sitio Regional de la Red Hemisférica de Reservas para Aves Playeras, dado el elevado porcentaje de la población mundial y regional de ostreros negros que allí residen durante la temporada reproductiva. Además, dado que la Isla Middleton podría ser el sitio más importante de Alaska para Haematopus bachmani, sugerimos que debería ser protegida del desarrollo en el futuro.
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Mayo, L. R., and R. S. March. "Air Temperature and Precipitation at Wolverine Glacier, Alaska; Glacier Growth in a Warmer, Wetter Climate." Annals of Glaciology 14 (1990): 191–94. http://dx.doi.org/10.1017/s0260305500008557.
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Measurements at Wolverine Glacier, Alaska, from 1968 to 1988 indicate unsteady increases of air temperature and precipitation since the early 1970s. These increases were due almost entirely to changes in winter. Variations in annual temperature and precipitation at Wolverine Glacier and at Seward, a nearby climatological station at sea level, correlate positively with global temperature variations and are in general agreement with the changes at high latitudes predicted by five recent general atmospheric circulation models forced by anticipated rises of CO2. A consequence of the air temperature and precipitation increases at Wolverine Glacier was a change to a generally positive mass balance after 1976. Although these observations in the coastal maritime climate of Alaska run against the common, oversimplified notion that in a warming climate glaciers will melt, causing sea level to rise, they are logical and easily understood when the sensitivity of the glacier to the seasonal distribution of the changes is considered. The observed seasonal changes at Wolverine Glacier also are in agreement with global climate models. Snow precipitation and glacier accumulation increased, but at the same time warming affected only these those temperatures below about −5°C, and melting was not altered. The extent of this response is not well known, but the process may be taking place in other important glacierized regions.
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Mayo, L. R., and R. S. March. "Air Temperature and Precipitation at Wolverine Glacier, Alaska; Glacier Growth in a Warmer, Wetter Climate." Annals of Glaciology 14 (1990): 191–94. http://dx.doi.org/10.3189/s0260305500008557.
Full textAbstract:
Measurements at Wolverine Glacier, Alaska, from 1968 to 1988 indicate unsteady increases of air temperature and precipitation since the early 1970s. These increases were due almost entirely to changes in winter. Variations in annual temperature and precipitation at Wolverine Glacier and at Seward, a nearby climatological station at sea level, correlate positively with global temperature variations and are in general agreement with the changes at high latitudes predicted by five recent general atmospheric circulation models forced by anticipated rises of CO2.A consequence of the air temperature and precipitation increases at Wolverine Glacier was a change to a generally positive mass balance after 1976. Although these observations in the coastal maritime climate of Alaska run against the common, oversimplified notion that in a warming climate glaciers will melt, causing sea level to rise, they are logical and easily understood when the sensitivity of the glacier to the seasonal distribution of the changes is considered. The observed seasonal changes at Wolverine Glacier also are in agreement with global climate models. Snow precipitation and glacier accumulation increased, but at the same time warming affected only these those temperatures below about −5°C, and melting was not altered. The extent of this response is not well known, but the process may be taking place in other important glacierized regions.
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Hastings, Kelly K., Michael J. Rehberg, Gregory M. O’corry-Crowe, Grey W. Pendleton, Lauri A. Jemison, and Thomas S. Gelatt. "Demographic consequences and characteristics of recent population mixing and colonization in Steller sea lions, Eumetopias jubatus." Journal of Mammalogy 101, no. 1 (December 28, 2019): 107–20. http://dx.doi.org/10.1093/jmammal/gyz192.
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Abstract Steller sea lions (Eumetopias jubatus) are composed of two genetically distinct metapopulations (an increasing “eastern” and a reduced and endangered “western” population, or stock for management purposes in U.S. waters) that are only recently mixing at new rookeries in northern Southeast Alaska, east of the current stock boundary. We used mark-recapture models and 18 years of resighting data of over 3,500 individuals marked at the new rookeries and at neighboring long-established rookeries in both populations to examine morphology, survival, and movement patterns of pups born at new rookeries based on whether they had mitochondrial DNA haplotypes from the western or eastern population (mtW or mtE); examine survival effects of dispersal to the Eastern Stock region for animals born in the Western Stock region; and estimate minimum proportions of animals with western genetic material in regions within Southeast Alaska. Pups born at new rookeries with mtW had similar mass, but reduced body condition and first-year survival (approximately −10%) compared to pups with mtE. mtE pups ranged more widely than mtW pups, including more to the sheltered waters of Southeast Alaska’s Inside Passage. Fitness benefits for western-born females that dispersed to Southeast Alaska were observed as higher female survival (+0.127, +0.099, and +0.032 at ages 1, 2, and 3+) and higher survival of their female offspring to breeding age (+0.15) compared to females that remained west of the boundary. We estimated that a minimum of 38% and 13% of animals in the North Outer Coast–Glacier Bay and Lynn Canal–Frederick Sound regions in Southeast Alaska, respectively, carry genetic information unique to the western population. Despite fitness benefits to western females that dispersed east, asymmetric dispersal costs or other genetic or maternal effects may limit the growth of the western genetic lineage at the new rookeries, and these factors require further study.
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Alerstam, Thomas, Johan Bäckman, Gudmundur A. Gudmundsson, Anders Hedenström, Sara S. Henningsson, Håkan Karlsson, Mikael Rosén, and Roine Strandberg. "A polar system of intercontinental bird migration." Proceedings of the Royal Society B: Biological Sciences 274, no. 1625 (August 7, 2007): 2523–30. http://dx.doi.org/10.1098/rspb.2007.0633.
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Studies of bird migration in the Beringia region of Alaska and eastern Siberia are of special interest for revealing the importance of bird migration between Eurasia and North America, for evaluating orientation principles used by the birds at polar latitudes and for understanding the evolutionary implications of intercontinental migratory connectivity among birds as well as their parasites. We used tracking radar placed onboard the ice-breaker Oden to register bird migratory flights from 30 July to 19 August 2005 and we encountered extensive bird migration in the whole Beringia range from latitude 64° N in Bering Strait up to latitude 75° N far north of Wrangel Island, with eastward flights making up 79% of all track directions. The results from Beringia were used in combination with radar studies from the Arctic Ocean north of Siberia and in the Beaufort Sea to make a reconstruction of a major Siberian–American bird migration system in a wide Arctic sector between longitudes 110° E and 130° W, spanning one-third of the entire circumpolar circle. This system was estimated to involve more than 2 million birds, mainly shorebirds, terns and skuas, flying across the Arctic Ocean at mean altitudes exceeding 1 km (maximum altitudes 3–5 km). Great circle orientation provided a significantly better fit with observed flight directions at 20 different sites and areas than constant geographical compass orientation. The long flights over the sea spanned 40–80 degrees of longitude, corresponding to distances and durations of 1400–2600 km and 26–48 hours, respectively. The birds continued from this eastward migration system over the Arctic Ocean into several different flyway systems at the American continents and the Pacific Ocean. Minimization of distances between tundra breeding sectors and northerly stopover sites, in combination with the Beringia glacial refugium and colonization history, seemed to be important for the evolution of this major polar bird migration system.
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Rehberg, M. J., L. D. Rea, and C. A. Eischens. "Overwintering Steller sea lion (Eumetopias jubatus) pup growth and behavior prior to weaning." Canadian Journal of Zoology 96, no. 2 (February 2018): 97–106. http://dx.doi.org/10.1139/cjz-2016-0296.
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We measured individual growth, looked for evidence of weaning, and examined the interaction of these changes with diving behavior in young-of-year Steller sea lion (Eumetopias jubatus (Schreber, 1776)) pups in Alaska, USA, during their first winter. Steller sea lions employ an income breeding strategy, in which females provision their young over an individually variable period of months to years. Thus, we set out to identify whether these young sea lions showed evidence of weaning during the challenging winter months, describe the nature of their growth during this time, and examine their behaviors in light of these changes. Between 2005 and 2008, we captured 71 pups during early winter and recaptured 33 of these pups in early spring. Mark–resight and stable nitrogen isotope ratios in vibrissae indicated most pups remained nutritionally dependent on adult females throughout the winter. All pups increased both mass and lipid mass, with half of growth contributed by lipid mass. Changes in behavior were not correlated with growth excepting a weak but significant effect on rate of vertical travel. This study demonstrated that capture–recapture of Steller sea lion pups is possible, provided seasonal timing, locations, and age classes are carefully considered for their likelihood of capture success.
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Mathews, Elizabeth A., Jamie N. Womble, Grey W. Pendleton, Lauri A. Jemison, John M. Maniscalco, and Greg Streveler. "Population growth and colonization of Steller sea lions in the Glacier Bay region of southeastern Alaska: 1970s-2009." Marine Mammal Science 27, no. 4 (March 1, 2011): 852–80. http://dx.doi.org/10.1111/j.1748-7692.2010.00455.x.
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Jorgenson, M., Gerald Frost, and Dorte Dissing. "Drivers of Landscape Changes in Coastal Ecosystems on the Yukon-Kuskokwim Delta, Alaska." Remote Sensing 10, no. 8 (August 14, 2018): 1280. http://dx.doi.org/10.3390/rs10081280.
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The Yukon-Kuskokwim Delta (YKD) is the largest delta in western North America and its productive coastal ecosystems support globally significant populations of breeding birds and a large indigenous population. To quantify past landscape changes as a guide to assessing future climate impacts to the YKD and how indigenous society may adapt to change, we photo-interpreted ecotypes at 600 points within 12 grids in a 2118 km2 area along the central YKD coast using a time-series of air photos from 1948–1955 and 1980 and satellite images from 2007–2008 (IKONOS) and 2013–2016 (WorldView). We found that ecotype classes changed 16.2% (342 km2) overall during the ~62 years. Ecotypes changed 6.0% during 1953–1980, 7.2% during 1980–2007 and 3.8% during 2007–2015. Lowland Moist Birch-Ericaceous Low Scrub (−5.0%) and Coastal Saline Flat Barrens (−2.3%) showed the greatest decreases in area, while Lowland Water Sedge Meadow (+1.7%) and Lacustrine Marestail Marsh (+1.3%) showed the largest increases. Dominant processes affecting change were permafrost degradation (5.3%), channel erosion (3.0%), channel deposition (2.2%), vegetation colonization (2.3%) and lake drainage (1.5%), while sedimentation, water-level fluctuations, permafrost aggradation and shoreline paludification each affected <0.5% of the area. Rates of change increased dramatically in the late interval for permafrost degradation (from 0.06 to 0.26%/year) and vegetation colonization (from 0.03 to 0.16%/year), while there was a small decrease in channel deposition (from 0.05 to 0.0%/year) due largely to barren mudflats being colonized by vegetation. In contrast, rates of channel erosion remained fairly constant. The increased permafrost degradation coincided with increasing storm frequency and air temperatures. We attribute increased permafrost degradation and vegetation colonization during the recent interval mostly to the effects of a large storm in 2005, which caused extensive salt-kill of vegetation along the margins of permafrost plateaus and burial of vegetation on active tidal flats by mud that was later recolonized. Due to the combination of extremely flat terrain, sea-level rise, sea-ice reduction that facilitates more storm flooding and accelerating permafrost degradation, we believe the YKD is the most vulnerable region in the Arctic to climate warming.
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Ward, David H., Joel A. Schmutz, James S. Sedinger, Karen S. Bollinger, Philip D. Martin, and Betty A. Anderson. "Temporal and Geographic Variation in Survival of Juvenile Black Brant." Condor 106, no. 2 (May 1, 2004): 263–74. http://dx.doi.org/10.1093/condor/106.2.263.
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Abstract First-year survival has important implications for the structure and growth of populations. We examined variation in seasonal survival of first-year Pacific Black Brant (Branta bernicla nigricans) marked late in summer in Alaska at two brood-rearing areas on the Yukon-Kuskokwim Delta (Tutakoke and Kokechik) and one area on the Arctic Coastal Plain to provide insight into the magnitude and timing of mortality during fall migration. First-year survival was lower in early fall (15 July–1 October), when birds fledged from brood-rearing areas and migrated to their primary fall staging area at Izembek Lagoon, Alaska, than during late fall and early winter (1 October–15 February), when birds made a long-distance transoceanic flight (>5000 km) to wintering areas in Baja California, Mexico. When compared to other years, monthly survival during early fall was 20–24% lower in 1992, the year of latest hatch dates and slowest growth of goslings. There was strong evidence to indicate that survival varied geographically within the early fall period. Monthly survival estimates during early fall were lowest for birds from Tutakoke, highest for birds from the Arctic Coastal Plain, and intermediate at Kokechik. Our findings revealed that most juvenile mortality occurred during the first 2 months following banding, and variation in juvenile survival during this period was likely influenced significantly by environmental parameters and habitat conditions on the breeding grounds. Monthly survival estimates during the subsequent 4 months were similar across geographic areas, and long-distance migration was likely the most important contributor to juvenile mortality during this period. Variación Temporal y Geográfica en la Supervivencia de Juveniles de Branta bernicla nigricans Resumen. La supervivencia durante el primer año de vida tiene implicancias importantes para la estructura y el crecimiento de las poblaciones. Examinamos la variación en la supervivencia estacional en individuos añales de Branta bernicla nigricans marcados al final del verano en Alaska en dos áreas de cría del Delta Yukon-Kuskokwim (Tutakoke y Kokechik) y un área en la planicie costera ártica para brindar información sobre la magnitud y el esquema temporal de mortalidad durante la migración de otoño. La supervivencia durante el primer año fue menor a principios del otoño (15 July–1 October), cuando las aves abandonaron las áreas de cría y migraron hacia el área principal de permanencia otoñal en Izembek Lagoon, Alaska, que durante fines de otoño y comienzos del invierno (1 October–15 February), cuando las aves realizaron un vuelo transoceánico de larga distancia (>5000 km) hacia las áreas de invernada en Baja California, México. Comparando con otros años, la supervivencia mensual durante principios del otoño fue un 20–24% menor en 1992, el año con fechas más tardías de eclosión y con crecimiento más lento de los polluelos. Hubo fuerte evidencia para indicar que la supervivencia varió geográficamente a principios del otoño. Las estimaciones mensuales de supervivencia durante principios del otoño fueron menores para las aves de Tutakoke, mayores para las aves de la planicie costera ártica, e intermedias para Kokechik. Nuestros resultados revelaron que la mayoría de la mortalidad juvenil ocurrió durante los dos primeros meses luego del anillado, y la variación en la supervivencia de los juveniles durante este período fue probablemente influenciada de forma significativa por parámetros ambientales y condiciones del hábitat en las áreas de cría. Las estimaciones mensuales de supervivencia durante los cuatro meses siguientes fueron similares para las distintas áreas geográficas, y la migración de larga distancia fue probablemente la causa más importante de mortalidad juvenil durante este período.
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Dorendorf, Ross R., Kelly J. Sivy, Martin D. Robards, Tom W. Glass, and Kristine L. Pilgrim. "Spring food habits of Wolverine (Gulo gulo) in the Colville River watershed, Alaska." Canadian Field-Naturalist 132, no. 3 (April 11, 2019): 268–78. http://dx.doi.org/10.22621/cfn.v132i3.1947.
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Wolverines (Gulo gulo) are relatively abundant on the North Slope of Alaska, an Arctic ecosystem dominated by tundra habitats that run north from the Brooks Range across a wide coastal plain to the Beaufort Sea. The region contains a range of potential Wolverine prey species, including ungulates (Caribou [Rangifer tarandus], Moose [Alces americanus]), Arctic Ground Squirrel (Urocitellus parryii), and both Soricidae and Cricetidae species. The seasonal composition of these, and other prey species, in the Wolverines’ diet is not well understood. We collected Wolverine scats during spring (March–May) on the North Slope while tracking animals from snowmobiles and with helicopters that visited areas identified as of interest during ground surveys or using global positioning system collared animals. We analyzed prey remains in 48 scat samples based on hair, bone, and other prey fragments. We then calculated frequency of occurrence, percentage of occurrence, and weighted percent volume for each major prey category detected. We confirmed species identity of scats as Wolverine by amplifying the control region of the mitochondrial DNA. We estimated spring diet diversity and richness based on nine major prey categories detected in scats. Ungulates and cricetids together constituted 69% of the Wolverines’ spring diet, with Snowshoe Hare (Lepus americanus) constituting 9%, fox (Vulpes spp.) 6%, Arctic Ground Squirrel 2%, birds 2%, American Beaver (Castor canadensis) less than 1%, and unknown 6%.
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LEHNERT, HELMUT, JOHN HOCEVAR, and ROBERT P. STONE. "A new species of Aaptos (Porifera, Hadromerida, Suberitidae) from Pribilof Canyon, Bering Sea, Alaska." Zootaxa 1939, no. 1 (November 21, 2008): 65–68. http://dx.doi.org/10.11646/zootaxa.1939.1.8.
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The Bering Sea is predominantly a shallow sea, with a massive shelf mostly shallower than 100 m. Pribilof Canyon and Zhemchug Canyon, two of the largest submarine canyons in the world, were explored in August 2007, by the Greenpeace vessel “Esperanza”, with manned submersibles and a remotely operated vehicle (ROV) to depths of 1000 m. Specimens were collected with hydraulic manipulators operated by the pilots of the submersibles or with the ROV. Once on deck the specimens were transferred to ethanol. Pribilof Canyon is 426 km long and 1800 m deep, while Zhemchug Canyon is even larger and reaches depths of more than 2600 m (Normark and Carlson 2003). Here we describe a new species of Aaptos and compare it with representative congeners. The genus Aaptos was erected by Gray (1867) for Aaptos aaptos, described by Schmidt (1864) as Ancorina aaptos. Today, Aaptos is placed in Suberitidae Schmidt, 1870 and contains 21 species (Van Soest et al. 2005). For a more detailed historical review of the family and genus we refer to the publications of Kelly-Borges & Bergquist (1994) and to Van Soest (2002). According to Van Soest (2002), Aaptos is separated from other Suberitidae by its spherical or lobate growth forms, and by the presence of a strictly radial skeleton that contains characteristic strongyloxeas. The type species was described from the Mediterranean Sea (Algeria) and was then reported from many other areas of the world. These subsequent records likely represent additional undescribed species of Aaptos (Van Soest, 2002).
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Day, Robert H., Alexander K. Prichard, and Debora A. Nigro. "Ecological Specialization and Overlap of Brachyramphus Murrelets in Prince William Sound, Alaska." Auk 120, no. 3 (July 1, 2003): 680–99. http://dx.doi.org/10.1093/auk/120.3.680.
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Abstract We compared habitat use and niche overlap in the closely related seabirds Kittlitz’s (Brachyramphus brevirostris) and Marbled (B. marmoratus) Murrelets in nearshore waters of Prince William Sound, Alaska, in 1996–1998, and examined the relationship between near shore habitat use and morphology of those two species. Within bays, the distribution of Kittlitz’s Murrelet groups diverged the most from randomness for the variables habitat type (preferring [i.e. using significantly more than what is available] glacial-affected and glacial-stream-affected habitats), distance to shore (preferring areas 51–100 m from shore), and water clarity (preferring highly turbid water), whereas the distribution of Marbled Murrelet groups diverged the most from randomness for the variables habitat type (preferring glacial-unaffected habitats), ice cover (preferring areas of no ice), and sea-surface temperature (SST) (preferring temperatures = 6°C). The probability of a group of birds being Kittlitz’s Murrelets was determined most strongly by water clarity. Kittlitz’s Murrelet groups were more common in the more heavily glaciated College and Harriman fjords than in the other two bays and more common in early and midsummer than in late summer; the reverse was true for Marbled Murrelet groups. Marbled Murrelet groups had the least niche overlap with Kittlitz’s Murrelet groups in water clarity, SST, and site, whereas Kittlitz’s Murrelets had the least overlap with Marbled Murrelets in habitat type and water clarity. Similarly, Kittlitz’s Murrelet groups occurred in water significantly more turbid than did Marbled Murrelet groups in two of four habitat types. Kittlitz’s Murrelets had eyes (as indicated by orbit diameter) that were significantly larger in proportional size than Marbled Murrelets. We propose that these two species are specialized for foraging in different water types, with specialization of the Kittlitz’s Murrelet for turbid water of glacial origin leading to optical specialization.
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Sánchez-Montes, Maria Luisa, Erin L. McClymont, Jeremy M. Lloyd, Juliane Müller, Ellen A. Cowan, and Coralie Zorzi. "Late Pliocene Cordilleran Ice Sheet development with warm northeast Pacific sea surface temperatures." Climate of the Past 16, no. 1 (February 14, 2020): 299–313. http://dx.doi.org/10.5194/cp-16-299-2020.
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Abstract. The initiation and evolution of the Cordilleran Ice Sheet are relatively poorly constrained. International Ocean Discovery Program (IODP) Expedition 341 recovered marine sediments at Site U1417 in the Gulf of Alaska (GOA). Here we present alkenone-derived sea surface temperature (SST) analyses alongside ice-rafted debris (IRD), terrigenous, and marine organic matter inputs to the GOA through the late Pliocene and early Pleistocene. The first IRD contribution from tidewater glaciers in southwest Alaska is recorded at 2.9 Ma, indicating that the Cordilleran Ice Sheet extent increased in the late Pliocene. A higher occurrence of IRD and higher sedimentation rates in the GOA during the early Pleistocene, at 2.5 Ma, occur in synchrony with SSTs warming on the order of 1 ∘C relative to the Pliocene. All records show a high degree of variability in the early Pleistocene, indicating highly efficient ocean–climate–ice interactions through warm SST–ocean evaporation–orographic precipitation–ice growth mechanisms. A climatic shift towards ocean circulation in the subarctic Pacific similar to the pattern observed during negative Pacific Decadal Oscillation (PDO) conditions today occurs with the development of more extensive Cordilleran glaciation and may have played a role through increased moisture supply to the subarctic Pacific. The drop in atmospheric CO2 concentrations since 2.8 Ma is suggested as one of the main forcing mechanisms driving the Cordilleran glaciation.
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Ebert, Thomas A., Louis M. Barr, James L. Bodkin, Dirk Burcham, Dominique Bureau, Henry S. Carson, Nancy L. Caruso, et al. "Size, growth, and density data for shallow-water sea urchins from Mexico to the Aleutian Islands, Alaska, 1956-2016." Ecology 99, no. 3 (January 23, 2018): 761. http://dx.doi.org/10.1002/ecy.2123.
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Haas, Diane L., David A. Ebert, and Gregor M. Cailliet. "Comparative age and growth of the Aleutian skate, Bathyraja aleutica, from the eastern Bering Sea and Gulf of Alaska." Environmental Biology of Fishes 99, no. 11 (September 9, 2016): 813–28. http://dx.doi.org/10.1007/s10641-016-0518-5.
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Pyper, Brian J., and Randall M. Peterman. "Relationship among adult body length, abundance, and ocean temperature for British Columbia and Alaska sockeye salmon (Oncorhynchus nerka), 1967–1997." Canadian Journal of Fisheries and Aquatic Sciences 56, no. 10 (October 1, 1999): 1716–20. http://dx.doi.org/10.1139/f99-167.
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Body length of adult Pacific sockeye salmon (Oncorhynchus nerka) has decreased significantly in recent years. We used 69 time series of age-specific body-length data (1967-1997) for 30 sockeye salmon stocks from southern British Columbia to western Alaska to test hypotheses about the effects of oceanographic conditions and competition on growth rate of sockeye salmon. Using principal components analysis (PCA), we constructed a single time series (PC1) that represented the dominant pattern of variability in length-at-age shared among these stocks. Taking into account time trends and autocorrelation in residuals, we found that increases in total Gulf of Alaska sockeye abundance and increases in sea-surface temperature (SST) across the Gulf of Alaska were significantly associated with reduced adult body length. Abundance and SST together accounted for 71% of the variability in PC1. Although researchers have documented increases in both abundance of sockeye salmon and their food in the northeastern Pacific Ocean over the last few decades, it is possible that increased food was more than offset by increased sockeye abundance, leading to greater competition and reduced body size.
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Bergmann, Pamela Ann. "Implementation and Revision of the Wildlife Protection Guidelines for Alaska's Federal On-Scene Coordinators." International Oil Spill Conference Proceedings 1991, no. 1 (March 1, 1991): 137–39. http://dx.doi.org/10.7901/2169-3358-1991-1-137.
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ABSTRACT The Alaska Regional Response Team (RRT) established the Wildlife Protection Working Group in September 1987 to develop and maintain guidelines to assist Alaska's federal on-scene coordinators (OSC) in dealing with potential wildlife impacts resulting from oil spills. The working group is composed of representatives of four federal and state agencies and three special-interest groups. The guidelines, which were adopted by the Alaska RRT on December 14, 1988, address three response strategies: controlling the release and spread of oil to protect wildlife, keeping wildlife away from spills through the use of deterrent techniques, and attempting to capture and rehabilitate oiled wildlife. Since adoption by the Alaska RRT, the guidelines have been used in conjunction with response activities associated with the following spills: the Swallow diesel fuel and fuel oil spill near Dutch Harbor on February 27, 1989, the Exxon Valdez crude oil spill in Prince William Sound on March 24, 1989, and the Milos Reefer fuel oil and diesel fuel spill on St. Matthew Island on November 15, 1989. In the Swallow incident, protective booming, bird hazing, and bird capture and rehabilitation programs were conducted in accordance with the guidelines. In the Exxon Valdez incident, information in the guidelines was used to establish the sea otter rescue program and to begin implementation of the bird capture and rehabilitation program. In the Milos Reefer spill, the guidelines were used as the basis for a decision not to initiate a rescue program for birds oiled as a result of the vessel's grounding. In October 1989, the working group met to conduct a review of the guidelines based on experience gained through the Swallow and Exxon Valdez incidents. As a result of this meeting, seven principal additions have been proposed for the guidelines.
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Cronin-Fine, Lee, and André E. Punt. "There is no best method for constructing size-transition matrices for size-structured stock assessments." ICES Journal of Marine Science 77, no. 1 (November 22, 2019): 136–47. http://dx.doi.org/10.1093/icesjms/fsz217.
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Abstract Stock assessment methods for many invertebrate stocks, including crab stocks in the Bering Sea of Alaska, rely on size-structured population dynamics models. A key component of these models is the size-transition matrix, which specifies the probability of growing from one size-class to another after a certain period of time. Size-transition matrices can be defined using three parameters, the growth rate (k), asymptotic size (L∞), and variability in the size increment. Most assessments use mark-recapture data to estimate these parameters and assume that all individuals follow the same growth curve, but this can lead to biased estimates of growth parameters. We compared three approaches: the traditional approach, the platoon method, and a numerical integration method that allows k, L∞, or both to vary among individuals, under a variety of scenarios using simulated data based on golden king crabs (Lithodes aequispinus) in the Aleutian Islands region of Alaska. No estimation method performed best for all scenarios. The number of size-classes in the size-transition matrix and how the data are generated heavily dictate performance. However, we recommend the numerical integration method that allows L∞ to vary among individuals and smaller size-class widths.
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Miller, C. N., L. K. Polasek, A. C. M. Oliveira, C. J. Frost, and J. M. Maniscalco. "Milk fatty acid composition of perinatal and foraging Steller sea lions (Eumetopias jubatus): examination from pup stomachs." Canadian Journal of Zoology 96, no. 2 (February 2018): 153–62. http://dx.doi.org/10.1139/cjz-2016-0015.
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To investigate the milk fatty acid composition of female Steller sea lions (Eumetopias jubatus (Schreber, 1776)) between and within maternal states (i.e., perinatal or foraging), milk samples were collected in 2010 and 2011 via gastric intubation from Steller sea lion pups on a small rookery in the central Gulf of Alaska. Maternal states of lactating females were determined upon reuniting with their sampled pups via remotely operated video cameras on the rookery. Milk fatty acid composition between Steller sea lion maternal states was significantly different, and thus can be utilized to distinguish between perinatal and foraging Steller sea lions of the same geographic region in the absence of direct observation. However, milk fatty acid composition remained relatively constant within perinatal Steller sea lions, suggesting steady mobilization of fatty acids from blubber to milk, and within foraging Steller sea lions, implying females forage on similar prey species within several days after their perinatal period. Differences in milk fatty acid composition between maternal states, including differences in the relative percentages of polyunsaturated fatty acids, may have important implications for growth and development of offspring.
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Key, Jeffrey R., Yong Liu, and Robert S. Stone. "Development and evaluation of surface shortwave flux parameterizations for use in sea-ice models." Annals of Glaciology 25 (1997): 33–37. http://dx.doi.org/10.1017/s0260305500013756.
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The surface radiation budget of the polar regions strongly influences ice growth and melt. Thermodynamic sea-ice models therefore require accurate yet computationally efficient methods of computing radiative fluxes. In this paper a new parameterization of the downwelling shortwave radiation flux at the Arctic surface is developed and compared to a variety of existing schemes. Parameterized llnxes are compared to in situ measurements using data for one year at Barrow, Alaska. Our results show that the new parameterization can estimate the downwelling shortwave flux with mean and root mean square errors of 1 and 5%, respectively, for clear conditions and 5 and 20% for cloudy conditions. The new parameterization offers a unified approach to estimating downwelling shortwave fluxes under clear and cloudy conditions, and is more accurate than existing schemes.
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Key, Jeffrey R., Yong Liu, and Robert S. Stone. "Development and evaluation of surface shortwave flux parameterizations for use in sea-ice models." Annals of Glaciology 25 (1997): 33–37. http://dx.doi.org/10.3189/s0260305500013756.
Full textAbstract:
The surface radiation budget of the polar regions strongly influences ice growth and melt. Thermodynamic sea-ice models therefore require accurate yet computationally efficient methods of computing radiative fluxes. In this paper a new parameterization of the downwelling shortwave radiation flux at the Arctic surface is developed and compared to a variety of existing schemes. Parameterized llnxes are compared to in situ measurements using data for one year at Barrow, Alaska. Our results show that the new parameterization can estimate the downwelling shortwave flux with mean and root mean square errors of 1 and 5%, respectively, for clear conditions and 5 and 20% for cloudy conditions. The new parameterization offers a unified approach to estimating downwelling shortwave fluxes under clear and cloudy conditions, and is more accurate than existing schemes.
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Clumpner, Curt. "WILDLIFE RESPONSE IN A REMOTE ALASKAN SPILL: TESTING A CENTRALIZED SYSTEM." International Oil Spill Conference Proceedings 1997, no. 1 (April 1, 1997): 351–56. http://dx.doi.org/10.7901/2169-3358-1997-1-351.
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ABSTRACT In 1991 the International Bird Rescue Research Center, Alyeska Pipeline Service Company, and Alaska Clean Seas teamed up to design and implement a wildlife response system that could work successfully in a state with an area of nearly 600,000 square miles, more than 6000 miles of coastline, and hundreds of islands. In a state that is spread over more than 15 degrees of latitude and 45 degrees of longitude, the system would need to work in all sorts of weather and at all times of the year in three major climatic zones (marine coastal, subarctic, and arctic). It was decided that the best way to maximize resources and coverage was to design a system with a centralized oiled wildlife rehabilitation center in Anchorage: the Alaska Wildlife Response Center. This would allow one to use resources that would otherwise be unavailable in a timely fashion in many of the areas at greatest risk for an oil spill. It would also maximize cost effectiveness by minimizing the amount of equipment and personnel that would have to be moved and supported in remote areas of the state. A centralized system would, however, potentially require that the affected wildlife be transported long distances to be rehabilitated. In February 1996, a spill off the north coast of St. Paul Island in the Bering Sea provided the first real test of this system. It required the capture, stabilization, and transport of nearly 200 oiled birds under quite difficult and typical Alaska conditions. This paper will discuss the problems and solutions encountered in mounting a wildlife response to an oil spill in a remote area with inclement weather conditions and few local resources. It will focus on what makes responding in Alaska different from responding in most other parts of the United States, and on what was done differently in this response to make it a success. This paper will show how a system based on a centralized facility can work successfully, as was evidenced by the high percentage of released wildlife, when it involves teamwork among all organizations, agencies, and individuals involved.
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Sealy, Spencer G., and Harry R. Carter. "Body Condition and Survival of Vagrant Long-billed Murrelets, Brachyramphus perdix, in North America." Canadian Field-Naturalist 126, no. 1 (October 1, 2012): 6. http://dx.doi.org/10.22621/cfn.v126i1.1288.
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From 1979 through 2009, 81 records of long-distance vagrancy in the Long-billed Murrelet (Brachyramphus perdix) in North America south of Alaska were examined to assess body condition and survival after first observation. Sixty-one records were of live birds, of which 38 (62.3%) were discovered at sea along the west coast of North America, 18 (29.5%) were encountered inland, and 5 (8.2%) were encountered along the Atlantic coast. Fifteen of the 20 individuals salvaged (19 adults, 1 juvenile) were discovered on lake shores (75.0%) and the other 5 (25.0%) on marine coasts; 85.0% were dead when initially found (15 dead, 2 shot), and 3 (15.0%) were moribund (2 died within one day, 1 later released). Of 10 sexed individuals, 5 were adult males, 4 were adult females, and 1 was a juvenile female. Eight of 10 murrelets observed foraging were diving on lakes, but 2 others surfaced with fish; two species of common freshwater fish were removed from stomachs of 2 birds shot by hunters. Most birds (72.1%, n = 61) disappeared after one observation, which suggests survival and moving on; one bird stayed at the same location for at least 25 days before disappearing. Dead or dying Long-billed Murrelets found on shorelines of fresh water may have been too emaciated to regain lost mass after arrival—they weighed less than those shot, presumably because they were not able to locate prey or too weak to capture it. Survival for weeks or longer on freshwater stopover sites better explains how Long-billed Murrelets move across North America, with some reaching the Atlantic Ocean. Long-surviving vagrants may establish a new breeding population of Long-billed Murrelet on the west coast of North America.
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Hassanzadeh, M., M. H. Bozorgmehri Fard, J. Buyse, and E. Decuypere. "Beneficial effects of alternative lighting schedules on the incidence of ascites and on metabolic parameters of broiler chickens." Acta Veterinaria Hungarica 51, no. 4 (October 1, 2003): 513–20. http://dx.doi.org/10.1556/avet.51.2003.4.9.
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The beneficial effects of different lighting programmes on the incidence of ascites was investigated in an experiment with 360 three-day-old male broiler chickens. At 3 days of age, chicks were randomly divided over three rooms in a high-altitude farm, 2000 m above sea level. During days 14 to 28 ambient temperature decreased during the night but the minimum temperature did not descend below 15°C. In the first room the continuous lighting schedule (CL, 23L:1D) was maintained and in the second room an intermittent lighting schedule (IL, 1L:3D), repeated six times daily, was imposed from 3 days of age. In the third room, an increasing photoperiod schedule (IP, 4 to 14 days, 6L:18D; 15 to 21 days, 10L:14D; 22 to 28 days, 14L:10D; 29 to 35 days, 18L:6D; 36 to 42 days, 23L:1D) was provided. Mortality associated with right ventricular failure and ascites was numerically lower in birds reared under the IL and IP schedules compared to birds reared under the CL schedule, which can be attributed to the temporary reduction in relative growth and feed intake in IL and IP birds. It was concluded that the beneficial effect of lighting schedules could be due to a reduced metabolic rate as a consequence of the altered growth trajectory, as also reflected in the lower haematocrit and plasma T3 levels of IL and IP birds compared to CL birds.
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Yasumiishi, Ellen M., Ed V. Farley, Gregory T. Ruggerone, Beverly A. Agler, and Lorna I. Wilson. "Trends and Factors Influencing the Length, Compensatory Growth, and Size-Selective Mortality of Juvenile Bristol Bay, Alaska, Sockeye Salmon at Sea." Marine and Coastal Fisheries 8, no. 1 (January 2016): 315–33. http://dx.doi.org/10.1080/19425120.2016.1167793.
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Pingree-Shippee, Katherine A., Norman J. Shippee, and David E. Atkinson. "Overview of Bering and Chukchi Sea Wave States for Four Severe Storms following Common Synoptic Tracks." Journal of Atmospheric and Oceanic Technology 33, no. 2 (February 2016): 283–302. http://dx.doi.org/10.1175/jtech-d-15-0153.1.
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AbstractStrong storms occur regularly over the ocean west of Alaska. These systems often loiter, generating persistent winds that can result in fully developed marine states that can maximize damage and hazard potential. Detailed analyses of storm events in terms of the resultant wave states are uncommon. This analysis examines the wave states associated with four particular storm events over the Bering and Chukchi Seas: October 2004, September 2005, and November 2009, and a September 2011 event that exhibited north winds. For each event a brief synoptic overview is presented followed by consideration of the resultant wave state, including parameters such as wave steepness. Wave data come from NOAA’s WAVEWATCH III (WW3) operational global ocean wave model, implemented for scenario use at the Arctic Region Supercomputing Center at the University of Alaska Fairbanks. In situ data are available from several National Data Buoy Center buoys and a wave buoy located in the Bering Strait, funded by the U.S. Environmental Protection Agency and NOAA and deployed for a few months in 2011. WW3 accurately captures the timing and evolution of the observed wave action (onset, growth, peak, and decline of large, steep wind waves) for each of the storm events. As per previous climatologically oriented studies, WW3 is found to underestimate significant wave heights on the order of 0.5 m or less. Also larger discrepancies, on the order of 1–2 m, are observed during periods of peak significant wave heights (Hs). In some cases WW3 overestimated Hs, especially during periods of rapid Hs decline.
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Lewis, Tyler L., Tasha J. Dimarzio, and Jason L. Schamber. "Distribution and Population Size of Emperor Geese during the Breeding Season on the Seward Peninsula, Alaska." ARCTIC 74, no. 1 (March 16, 2021): 12–21. http://dx.doi.org/10.14430/arctic72055.
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The Emperor Goose (Anser canagicus) is a year-round occupant of northern latitudes, spending its entire annual cycle in coastal habitats of western Alaska and the Russian Far East. Over the last several decades, the Emperor Goose population underwent a pronounced decline, prompting 30 consecutive years of harvest closures, followed by a protracted recovery and the recent reopening of harvest. This recovery was primarily documented on the Yukon-Kuskokwim Delta in western Alaska, where an estimated 80% – 90% of the world’s Emperor Goose population breeds. However, the size and status of their population on the Seward Peninsula, Alaska, which is their only other significant breeding area in North America, remains almost completely unknown. Therefore, to better inform population and harvest management of Emperor Geese in western Alaska, we conducted extensive aerial surveys of Emperor Geese along the northern coast of the Seward Peninsula during the breeding season. During the summer of 2018, we surveyed 150 transects totaling 351 km2, for a total sampled fraction of 7.2% of the 4853 km2 survey area. Using a double-observer technique that accounted for detection probability, we estimated a population of 1226 (95% CI: 792 – 1660) Emperor Geese on the Seward Peninsula, of which 614 (95% CI: 416 – 811) were considered breeding birds based on their observed status as singles or pairs. Most Emperor Geese (61%) were found on barrier islands, even though these islands accounted for just 3.5% of the total survey area; the remaining geese were found in lowland coastal habitats (23%) or upland tundra (16%). Overall, our surveys indicate a small breeding population of Emperor Geese on the Seward Peninsula, which raises some conservation concern. Further reductions or extinction of this small population would leave Emperor Geese with only one significant breeding area in North America. Because Emperor Geese typically display high breeding site fidelity and female natal philopatry, any future growth of this small population will likely to need to come from within.
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Riedel, Ralf, Lucille M. Caskey, and Stuart H. Hurlbert. "Length-weight relations and growth rates of dominant fishes of the Salton Sea: implications for predation by fish-eating birds." Lake and Reservoir Management 23, no. 5 (December 2007): 528–35. http://dx.doi.org/10.1080/07438140709354036.
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