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
Demography of Dall's sheep in northwestern Alaska Demography of Dall's sheep in northwestern Alaska
Dall’s sheep in northwestern Alaska declined in the early 1990s following the severe 1989-90 and 1990-91 winters. In the Baird Mountains of Noatak National Preserve, estimates of adult sheep declined by 50% from 800 in 1989 to under 400 in 1991. Population counts remained low throughout 1991 to 1996, reaching a minimum of 244 adult sheep in 1996. Few lambs were observed during annual...
Authors
Christopher Kleckner, Mark S. Udevitz, Layne G. Adams, Brad S. Shults
Living on the edge: Distribution of Dungeness crab Cancer magister in a recently deglaciated fjord Living on the edge: Distribution of Dungeness crab Cancer magister in a recently deglaciated fjord
Glacier Bay, Alaska, has supported a productive Dungeness crab fishery, although the area where the fishery occurred was small relative to the remainder of the Bay. We hypothesized that 1 or more abiotic limiting factors prevented crabs from surviving in the upper Bay. We tested this hypothesis by systematically sampling for relative abundance of Dungeness crabs from the mouth to the...
Authors
S. James Taggart, P.N. Hooge, Jennifer Mondragon, Elizabeth Ross Hooge, A.G. Andrews
Phylogeography of Canada Geese (Branta canadensis) in western North America Phylogeography of Canada Geese (Branta canadensis) in western North America
Using molecular genetic markers that differ in mode of inheritance and rate of evolution, we examined levels and partitioning of genetic variation for seven nominal subspecies (11 breeding populations) of Canada Geese (Branta canadensis) in western North America. Gene trees constructed from mtDNA control region sequence data show that subspecies of Canada Geese do not have distinct mtDNA...
Authors
Kim T. Scribner, Sandra L. Talbot, John M. Pearce, Barbara J. Pierson, K.S. Bollinger, Dirk V. Derksen
Winter habitat use by female caribou in relation to wildland fires in interior Alaska Winter habitat use by female caribou in relation to wildland fires in interior Alaska
The role of wildland fire in the winter habitat use of caribou (Rangifer tarandus) has long been debated. Fire has been viewed as detrimental to caribou because it destroys the slow-growing climax forage lichens that caribou utilize in winter. Other researchers argued that caribou were not reliant on lichens and that fire may be beneficial, even in the short term. We evaluated the...
Authors
Kyle Joly, Bruce W. Dale, William B. Collins, Layne G. Adams
Assessing chick growth from a single visit to a seabird colony Assessing chick growth from a single visit to a seabird colony
We tested an approach to the collection of seabird chick growth data that utilizes a one-time sampling of chick measurements obtained during a single visit to a seabird colony. We assessed the development of Black-legged Kittiwake Rissa tridactyla chicks from a sample of measurements made on a single day during six years and compared these results to linear growth rates (g/day)...
Authors
J. Benson, R.M. Suryan, John F. Piatt
Using the bootstrap and fast Fourier transform to estimate confidence intervals of 2D kernel densities Using the bootstrap and fast Fourier transform to estimate confidence intervals of 2D kernel densities
No abstract available.
Authors
John W. Kern, Trent L. McDonald, Steven C. Amstrup, George M. Durner, Wallace P. Erickson
Surgical implantation of transmitters into fish Surgical implantation of transmitters into fish
Although the Animal Welfare Act does not cover poikilotherms, individual institutions and policies and legal requirements other than the Animal Welfare Act (e.g., the US Public Health Service and the Interagency Research Animal Committee's Principles for the Utilization and Care of Vertebrate Animals Used in Testing, Research, and Training) require the review of projects involving fish...
Authors
Daniel M. Mulcahy
Body molt of male long-tailed ducks in the nearshore waters of the north slope, Alaska Body molt of male long-tailed ducks in the nearshore waters of the north slope, Alaska
We examined the timing and intensity of body molt in relation to stage of remige growth for postbreeding adult male Long-tailed Ducks (Clangula hyemalis) off the coast of northern Alaska. During this period, remige and rectrix feathers are molted simultaneously with body feathers during the prebasic molt, which results in a period of increased energetic and nutritional demands. We...
Authors
M.D. Howell, J.B. Grand, Paul L. Flint
Identification of linear and threshold responses in streams along a gradient of urbanization in Anchorage, Alaska Identification of linear and threshold responses in streams along a gradient of urbanization in Anchorage, Alaska
We examined biotic and physiochemical responses in urbanized Anchorage, Alaska, to the percent of impervious area within stream basins, as determined by high-resolution IKONOS satellite imagery and aerial photography. Eighteen of the 86 variables examined, including riparian and instream habitat, macroinvertebrate communities, and water/sediment chemistry, were significantly correlated...
Authors
Robert T. Ourso, S.A. Frenzel
Incubation behaviour of Greater Scaup Aythya marila on the Yukon-Kuskokwim Delta, Alaska Incubation behaviour of Greater Scaup Aythya marila on the Yukon-Kuskokwim Delta, Alaska
This study examined the incubation behaviour of Greater Scaup Aythya marila on the Yukon-Kuskokwim Delta, Alaska. The goals of the study were to describe the incubation behaviour of Greater Scaup in terms of incubation constancy, recess frequency and recess length. The use of endogenous reserves by Greater Scaup was examined by determining weight loss over the incubation period. Further
Authors
Paul L. Flint
Post-breeding distribution of Long-tailed Ducks Clangula hyemalis from the Yukon-Kuskokwim Delta, Alaska Post-breeding distribution of Long-tailed Ducks Clangula hyemalis from the Yukon-Kuskokwim Delta, Alaska
Breeding populations of Long-tailed Ducks Clangula hyemalis have declined in western Alaska, particularly on the Yukon-Kuskokwim (Y-K) Delta, and the species is currently considered a species of particular concern by the U.S. Fish & Wildlife Service in Alaska. Potential factors that may have contributed to this decline that occurred away from the breeding grounds could not be considered...
Authors
Margaret R. Petersen, B. J. McCaffery, Paul L. Flint
Correlates to survival of juvenile sea otters in Prince William Sound, Alaska, 1992-1993 Correlates to survival of juvenile sea otters in Prince William Sound, Alaska, 1992-1993
We estimated survival of sea otters (Enhydra lutris) for 1 year post weaning during 1992-1993 in Prince William Sound (PWS), location of the 1989 Exxon Valdez oil spill. We sampled 38 pups in eastern PWS (EPWS), an unoiled area occupied by sea otters for 25 years. We compared survival between areas, sexes, and condition groups. We also examined the relation of blood parameters to...
Authors
Brenda E. Ballachey, James L. Bodkin, S. Howlin, A. M. Doroff, A.H. Rebar