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: 3084
Change in abundance of Pacific brant wintering in Alaska: Evidence of a climate warming effect? Change in abundance of Pacific brant wintering in Alaska: Evidence of a climate warming effect?
Winter distribution of Pacific Flyway brant (Branta bernicla nigricans) has shifted northward from low-temperate areas to sub-Arctic areas over the last 42 years. We assessed the winter abundance and distribution of brant in Alaska to evaluate whether climate warming may be contributing to positive trends in the most northern of the wintering populations. Mean surface air temperatures...
Authors
David H. Ward, Christian P. Dau, T. Lee Tibbitts, James S. Sedinger, Betty A. Anderson, James E. Hines
Evaluating the validity of using unverified indices of body condition Evaluating the validity of using unverified indices of body condition
Condition indices are commonly used in an attempt to link body condition of birds to ecological variables of interest, including demographic attributes such as survival and reproduction. Most indices are based on body mass adjusted for structural body size, calculated as simple ratios or residuals from regressions. However, condition indices are often applied without confirming their...
Authors
J.L. Schamber, Daniel Esler, Paul L. Flint
Late Glacial-Holocene Pollen-Based Vegetation History from Pass Lake, Prince of Wales Island, Southeastern Alaska Late Glacial-Holocene Pollen-Based Vegetation History from Pass Lake, Prince of Wales Island, Southeastern Alaska
A radiocarbon-dated history of vegetation development since late Wisconsin deglaciation has been reconstructed from pollen evidence preserved in a sediment core from Pass Lake on Prince of Wales Island, southeastern Alaska. The shallow lake is in the south-central part of the island and occupies a low pass that was filled by glacial ice of local origin during the late Wisconsin...
Authors
Thomas A. Ager, Joseph G. Rosenbaum
Eruption of Alaska volcano breaks historic pattern Eruption of Alaska volcano breaks historic pattern
In the late morning of 12 July 2008, the Alaska Volcano Observatory (AVO) received an unexpected call from the U.S. Coast Guard, reporting an explosive volcanic eruption in the central Aleutians in the vicinity of Okmok volcano, a relatively young (~2000-year-old) caldera. The Coast Guard had received an emergency call requesting assistance from a family living at a cattle ranch on the...
Authors
Jessica Larsen, Christina A. Neal, Peter Webley, Jeff Freymueller, Matthew Haney, Stephen McNutt, David Schneider, Stephanie Prejean, Janet Schaefer, Rick L. Wessels
Rebuttal of "Polar bear population forecasts: a public-policy forecasting audit" Rebuttal of "Polar bear population forecasts: a public-policy forecasting audit"
Observed declines in the Arctic sea ice have resulted in a variety of negative effects on polar bears (Ursus maritimus). Projections for additional future declines in sea ice resulted in a proposal to list polar bears as a threatened species under the United States Endangered Species Act. To provide information for the Department of the Interior's listing-decision process, the US...
Authors
Steven C. Amstrup, Hal Caswell, Eric DeWeaver, Ian Stirling, David C. Douglas, Bruce G. Marcot, Christine M. Hunter
Linking marine and freshwater growth in western Alaska Chinook salmon Oncorhynchus tshawytscha Linking marine and freshwater growth in western Alaska Chinook salmon Oncorhynchus tshawytscha
The hypothesis that growth in Pacific salmon Oncorhynchus spp. is dependent on previous growth was tested using annual scale growth measurements of wild Chinook salmon Oncorhynchus tshawytscha returning to the Yukon and Kuskokwim Rivers, Alaska, from 1964 to 2004. First-year marine growth in individual O. tshawytscha was significantly correlated with growth in fresh water. Furthermore...
Authors
G.T. Ruggerone, J.L. Nielsen, B.A. Agler
Persistence rates and detection probabilities of bird carcasses on beaches of Unalaska Island, Alaska following the wreck of the M/V Selendang Ayu Persistence rates and detection probabilities of bird carcasses on beaches of Unalaska Island, Alaska following the wreck of the M/V Selendang Ayu
Mark–recapture techniques were used to estimate persistence rates and detection probabilities of bird carcasses associated with the oil spill following the wreck of the M/V Selendang Ayu at Unalaska Island, Alaska. Only 14.6% of carcasses placed on beaches remained after 24 hours, and all carcasses that remained had been scavenged to some degree. Daily persistence rates for scavenged...
Authors
G. Vernon Byrd, Joel H. Reynolds, Paul L. Flint
Modeling haul-out behavior of walruses in Bering Sea ice Modeling haul-out behavior of walruses in Bering Sea ice
Understanding haul-out behavior of ice-associated pinnipeds is essential for designing and interpreting popula-tion surveys and for assessing effects of potential changes in their ice environments. We used satellite-linked transmitters to obtain sequential information about location and haul-out state for Pacific walruses, Odobenus rosmarus divergens (Il-liger, 1815), in the Bering Sea...
Authors
Mark S. Udevitz, Chadwick V. Jay, Anthony S. Fischbach, J. L. Garlich-Miller
Emsian (late Early Devonian) sponges from west-central and south-central Alaska Emsian (late Early Devonian) sponges from west-central and south-central Alaska
Relatively common specimens of the hypercalcified agelasiid sponge Hormospongia labyrinthica Rigby and Blodgett, 1983 and specimens of associated species of Hormospongia have been previously reported from Emsian and Eifelian stratigraphic units at several localities in south-central and southeastern Alaska (Rigby and Blodgett, 1983). Those sponges were first described from the type...
Authors
J.K. Rigby, R. B. Blodgett, N.K. Anderson
Relationships between hepatic trace element concentrations, reproductive status, and body condition of female greater scaup Relationships between hepatic trace element concentrations, reproductive status, and body condition of female greater scaup
We collected female greater scaup (Aythya marila) on the Yukon–Kuskokwim Delta, Alaska during two breeding seasons to determine if concentrations of 18 trace elements in livers and eggs were elevated and if hepatic concentrations correlated with body condition or affected reproductive status. Fifty-six percent, 5%, and 42% of females, respectively, had elevated hepatic cadmium (Cd: >3 μg...
Authors
Shannon S. Badzinski, Paul L. Flint, Kristen B. Gorman, Scott A. Petrie
Movements of juvenile Gyrfalcons from western and interior Alaska following departure from their natal areas Movements of juvenile Gyrfalcons from western and interior Alaska following departure from their natal areas
Juvenile raptors often travel thousands of kilometers from the time they leave their natal areas to the time they enter a breeding population. Documenting movements and identifying areas used by raptors before they enter a breeding population is important for understanding the factors that influence their survival. In North America, juvenile Gyrfalcons (Falco rusticolus) are routinely...
Authors
Carol L. McIntyre, David C. Douglas, Layne G. Adams
[Book review] Fish Welfare, by E. J. Branson [Book review] Fish Welfare, by E. J. Branson
Review of: E.J. Branson (ed): Fish Welfare Blackwell Publishing, Oxford, 2008, xvi + 300 pp, Hardback, ISBN-13:978-1-4051-4629-6.
Authors
Daniel M. Mulcahy