Publications
USGS research activities relevant to Alaska have yielded more than 9400 historical publications. This page features some of the most recent newsworthy research findings.
Filter Total Items: 3091
Variation in the response of an Arctic top predator experiencing habitat loss: Feeding and reproductive ecology of two polar bear populations Variation in the response of an Arctic top predator experiencing habitat loss: Feeding and reproductive ecology of two polar bear populations
Polar bears (Ursus maritimus) have experienced substantial changes in the seasonal availability of sea ice habitat in parts of their range, including the Beaufort, Chukchi, and Bering Seas. In this study, we compared the body size, condition, and recruitment of polar bears captured in the Chukchi and Bering Seas (CS) between two periods (1986–1994 and 2008–2011) when declines in sea ice...
Authors
Karyn D. Rode, Eric V. Regehr, David C. Douglas, George M. Durner, Andrew E. Derocher, Gregory W. Thiemann, Suzanne M. Budge
Two flysch belts having distinctly different provenance suggest no stratigraphic link between the Wrangellia composite terrane and the paleo-Alaskan margin Two flysch belts having distinctly different provenance suggest no stratigraphic link between the Wrangellia composite terrane and the paleo-Alaskan margin
The provenance of Jurassic to Cretaceous flysch along the northern boundary of the allochthonous Wrangellia composite terrane, exposed from the Lake Clark region of southwest Alaska to the Nutzotin Mountains in eastern Alaska, suggests that the flysch can be divided into two belts having different sources. On the north, the Kahiltna flysch and Kuskokwim Group overlie and were derived...
Authors
Chad P. Hults, Frederic H. Wilson, Raymond A. Donelick, Paul B. O'Sullivan
Brant (Branta bernnicla) Brant (Branta bernnicla)
The Brant (called Brent Goose in Europe) is a small dark goose that occurs throughout much of the northern hemisphere. In contrast to other goose species, Brant are characterized by their extensive use of native coastal habitats outside the breeding season. Three to four subspecies are recognized (see Systematics), mainly on the basis of plumage characteristics. The two/three North...
Authors
David H. Ward, Dirk V. Derksen, A. Reed, J.S. Sedinger
Recent lake ice-out phenology within and among lake districts of Alaska, U.S.A. Recent lake ice-out phenology within and among lake districts of Alaska, U.S.A.
The timing of ice-out in high latitudes is a fundamental threshold for lake ecosystems and an indicator of climate change. In lake-rich regions, the loss of ice cover also plays a key role in landscape and climatic processes. Thus, there is a need to understand lake ice phenology at multiple scales. In this study, we observed ice-out timing on 55 large lakes in 11 lake districts across...
Authors
Christopher D. Arp, Benjamin M. Jones, Guido Grosse
Genetics, recruitment, and migration patterns of Arctic Cisco (Coregonus autumnalis) in the Colville River, Alaska and Mackenzie River, Canada Genetics, recruitment, and migration patterns of Arctic Cisco (Coregonus autumnalis) in the Colville River, Alaska and Mackenzie River, Canada
Arctic cisco Coregonus autumnalis have a complex anadromous life history, many aspects of which remain poorly understood. Some life history traits of Arctic cisco from the Colville River, Alaska, and Mackenzie River basin, Canada, were investigated using molecular genetics, harvest data, and otolith microchemistry. The Mackenzie hypothesis, which suggests that Arctic cisco found in...
Authors
Christian E. Zimmerman, Andrew M. Ramey, S. Turner, Franz J. Mueter, S. Murphy, Jennifer L. Nielsen
Forest ecosystems: Vegetation, disturbance, and economics Forest ecosystems: Vegetation, disturbance, and economics
Forests cover about 47% of the Northwest (NW–Washington, Oregon, and Idaho) (Smith et al. 2009, fig. 5.1, table 5.1). The impacts of current and future climate change on NW forest ecosystems are a product of the sensitivities of ecosystem processes to climate and the degree to which humans depend on and interact with those systems. Forest ecosystem structure and function, particularly in
Authors
Jeremy S. Littell, Jeffrey A. Hicke, Sarah L. Shafer, Susan M. Capalbo, Laurie L. Houston, Patty Glick
Abdominally implanted satellite transmitters affect reproduction and survival rather than migration of large shorebirds Abdominally implanted satellite transmitters affect reproduction and survival rather than migration of large shorebirds
Satellite telemetry has become a common technique to investigate avian life-histories, but whether such tagging will affect fitness is a critical unknown. In this study, we evaluate multi-year effects of implanted transmitters on migratory timing and reproductive performance in shorebirds. Shorebirds increasingly are recognized as good models in ecology and evolution. That many of them...
Authors
Jos C. E. W. Hooijmeijer, Robert E. Gill, Daniel M. Mulcahy, T. Lee Tibbitts, Rosemarie Kentie, Gerrit J. Gerritsen, Leo W. Bruinzeel, David C. Tijssen, Christopher M. Harwood, Theunis Piersma
Simulated tsunami inundation for a range of Cascadia megathrust earthquake scenarios at Bandon, Oregon, USA Simulated tsunami inundation for a range of Cascadia megathrust earthquake scenarios at Bandon, Oregon, USA
Characterizations of tsunami hazards along the Cascadia subduction zone hinge on uncertainties in megathrust rupture models used for simulating tsunami inundation. To explore these uncertainties, we constructed 15 megathrust earthquake scenarios using rupture models that supply the initial conditions for tsunami simulations at Bandon, Oregon. Tsunami inundation varies with the amount and
Authors
Robert C. Witter, Yinglong J. Zhang, Kelin Wang, George R. Priest, Chris Goldfinger, Laura Stimely, John T. English, Paul A. Ferro
Migration and wintering areas of American Bitterns (Botaurus lentiginosus) that summer in central North America as determined by satellite and radio telemetry, 1998-2003 Migration and wintering areas of American Bitterns (Botaurus lentiginosus) that summer in central North America as determined by satellite and radio telemetry, 1998-2003
Twenty adult male American Bitterns (Botaurus lentiginosus) were marked on summer range in central North America with satellite tracking Platform Transmitter Terminals (PTTs) to document migration routes and wintering range. Nineteen complete fall migration routes were documented for 17 individuals. Of the successful migrations, 63% (n = 12) went to southern Florida, 32% (n = 6) to...
Authors
Guy Huschle, John E. Toepfer, David C. Douglas
Classification of freshwater ice conditions on the Alaskan Arctic Coastal Plain using ground penetrating radar and TerraSAR-X satellite data Classification of freshwater ice conditions on the Alaskan Arctic Coastal Plain using ground penetrating radar and TerraSAR-X satellite data
Arctic freshwater ecosystems have responded rapidly to climatic changes over the last half century. Lakes and rivers are experiencing a thinning of the seasonal ice cover, which may increase potential over-wintering freshwater habitat, winter water supply for industrial withdrawal, and permafrost degradation. Here, we combined the use of ground penetrating radar (GPR) and high-resolution...
Authors
Benjamin M. Jones, Alessio Gusmeroli, Christopher D. Arp, Tazio Strozzi, Guido Grosse, Benjamin V. Gaglioti, Matthew S. Whitman
A multilocus evaluation of ermine (Mustela erminea) across the Holarctic, testing hypotheses of Pleistocene diversification in response to climate change A multilocus evaluation of ermine (Mustela erminea) across the Holarctic, testing hypotheses of Pleistocene diversification in response to climate change
Aim: We examined data for ermine (Mustela erminea) to test two sets of diversification hypotheses concerning the number and location of late Pleistocene refugia, the timing and mode of diversification, and the evolutionary influence of insularization. Location: Temperate and sub-Arctic Northern Hemisphere. Methods: We used up to two mitochondrial and four nuclear loci from 237 specimens...
Authors
Natalie G. Dawson, Andrew G. Hope, Sandra L. Talbot, Joseph A. Cook
Analysis of a GRACE global mascon solution for Gulf of Alaska glaciers Analysis of a GRACE global mascon solution for Gulf of Alaska glaciers
We present a high-resolution Gravity Recovery and Climate Experiment (GRACE) mascon solution for Gulf of Alaska (GOA) glaciers and compare this with in situ glaciological, climate and other remote-sensing observations. Our GRACE solution yields a GOA glacier mass balance of –65 ± 11 Gt a–1 for the period December 2003 to December 2010, with summer balances driving the interannual...
Authors
Anthony Arendt, Scott Luthcke, Alex Gardner, Shad O’Neel, David Hill, Geir Moholdt, Waleed Abdalati