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: 3095
Growth rate is negatively correlated with hatch date in Black Brant Growth rate is negatively correlated with hatch date in Black Brant
Arctic geese nest in a highly seasonal environment in which ungrazed plants reach peak nitrogen concentrations when goslings hatch (Sedinger and Raveling 1986). Grazing by geese prolongs peak nutrient concentrations but reduces food availability. This should cause nutrient availability to decline seasonally. Here, we test the hypothesis that late-hatching goslings of Black Brant (Branta...
Authors
James S. Sedinger, Paul L. Flint
Evidence for color phase effects on the breeding and life history of Northern Fulmars Evidence for color phase effects on the breeding and life history of Northern Fulmars
About 15% of Northern Fulmars (Fulmarus glacialis) breeding on the Semidi Islands in 1979 had light-phase plumage; the remainder were dark. Fulmars of different plumage types mated indiscriminantly, but the lighter member of a mixed pair was more likely to be male than female. Pairs that included at least one light-phase member had lower breeding success than dark/dark pairs in one of...
Authors
Scott A. Hatch
A comparison of aerial and boat-based surveys for marbled murrelets in southeast Alaska, July 23-28, 1991 A comparison of aerial and boat-based surveys for marbled murrelets in southeast Alaska, July 23-28, 1991
Aerial and boat-based surveys for Marbled Murrelets (Brachyramphus marmoratus) were conducted simultaneously over short transect distances (ca. 2 km) in three different areas of the Alexander Archipelago to assess the accuracy and variability of aerial counts compared to boat-based counts. Additional aerial surveys were conducted over a wider geographic area to assess temporal and...
Authors
John F. Piatt, Bruce Conant, Chris Iverson
Effects of wind-hardened snow on foraging by reindeer (Rangifer tarandus) Effects of wind-hardened snow on foraging by reindeer (Rangifer tarandus)
Various methods were investigated for assessing the relationship between wind-hardened snow (upsik) and forage availability to reindeer. Mean bottom area of individual craters was not a function of depth, hardness or integrated hardness. Individual crater area was partially dependent on specific cratering time (r2 = .60). Cratering time per active period increased with integrated snow...
Authors
W. B. Collins, T. S. Smith
Apparatus for precise regulation and chilling of water temperatures in laboratory studies Apparatus for precise regulation and chilling of water temperatures in laboratory studies
Laboratory simulation of water temperature regimes that occur in subarctic rivers through winter necessitates the ability to maintain near‐freezing conditions. A heat‐exchanging apparatus is described that provided a convenient means of simulating the range of temperatures (0.5–12°C) that incubating eggs of salmon (Oncorhynchus spp.) typically experience in south‐central Alaskan...
Authors
D.B. Wangaard, John P. McDonell, Carl V. Burger, R.L. Wilmot
Patterns of seabird and marine mammal carcass deposition along the central California coast, 1980-1986 Patterns of seabird and marine mammal carcass deposition along the central California coast, 1980-1986
At monthly intervals from February 1980 through December 1986, a 14.5-km section of central California coastline was systematically surveyed for beach-cast carcasses of marine birds and mammals. Five hundred and fifty-four bird carcasses and 194 marine mammal carcasses were found. Common murres, western grebes, and Brandt's cormorants composed 45% of the bird total. California sea lions...
Authors
James L. Bodkin, Ronald J. Jameson
Inter- and intraspecific mitochondrial DNA variation in North American bears (Ursus) Inter- and intraspecific mitochondrial DNA variation in North American bears (Ursus)
We assessed mitochondrial DNA variation in North American black bears (Ursus americanus), brown bears (Ursus arctos), and polar bears (Ursus maritimus). Divergent mitochondrial DNA haplotypes (0.05 base substitutions per nucleotide) were identified in populations of black bears from Montana and Oregon. In contrast, very similar haplotypes occur in black bears across North America. This...
Authors
Matthew A. Cronin, Steven C. Amstrup, Gerald W. Garner, Ernest R. Vyse
Extent, causes and timing of moose calves mortality in western interior Alaska Extent, causes and timing of moose calves mortality in western interior Alaska
We examined the causes and timing of moose (Alces alces) calf mortality during 1988 90 in 2 locations in western interior Alaska. Annual survival rates of all calves in 1988 (0.34, n = 42) and 1989 (0.29, n=47) on the Nowitna National Wildlife Refuge (NWR) and in 1990 (0.25, n = 62) on the Koyukuk NWR were not significantly different. Survival rates of male and female calves were not
Authors
Timothy O. Osbourne, Thomas F. Paragi, James L. Bodkin, Andre J. Loranger, W. N. Johnson
Nest-site selection by Emperor Geese and Cackling Canada Geese Nest-site selection by Emperor Geese and Cackling Canada Geese
Differences were found in habitat structure between nest sites of Emperor Geese (Chen canagicus) and Cackling Canada Geese (Branta canadensis minima) during a 5-year study (1982-1986) at Kokechik Bay, Alaska. Emperor Geese tended to select sites that afforded concealment from avian predators before incubation began. Cackling Canada Geese tended to select sites that enhanced avoidance of...
Authors
Margaret R. Petersen
Time allocation by northern fulmars during the breeding season Time allocation by northern fulmars during the breeding season
Averaged over the whole breeding cycle (pre-laying through mid-chick stage), breeding fulmars spent about 39% of their time at the breeding site and 61% of their time at sea. Annual means of site occupancy before egg-laying were positively correlated with breeding success, suggesting that time allocation was a sensitive indicator of food availability in different years. Nonbreeding site...
Authors
Scott A. Hatch
Identification of a herpes-like virus in sea otters during rehabilitation after the T/V Exxon Valdez oil spill Identification of a herpes-like virus in sea otters during rehabilitation after the T/V Exxon Valdez oil spill
During implantation of radiotelemetry devices in sea otters (Enhydra lutris) at the Seward Otter Rehabilitation Center, surgical team members noted ulcers in the oral cavity of each of five animals examined. Oral lesions were identified in 25 of 27 otters examined at the center. Histological evaluation of the lesions revealed focal areas of mucosal epithelial necrosis with associated...
Authors
R.K. Harris, R.B. Moeller, T.P. Lipscomb, J.M. Pletcher, R.J. Haebler, P.A. Tuomi, C.R. McCormick, Anthony R. DeGange, Daniel M. Mulcahy, T.D. Williams
Immediate impact of the 'Exxon Valdez' oil spill on marine birds Immediate impact of the 'Exxon Valdez' oil spill on marine birds
On 24 March 1989, the oil tanker 'Exxon Valdez' spilled 260,000 barrels of crude oil in Prince William Sound, Alaska. Oil eventually drifted over $30,000\ {\rm km}^{2}$ of coastal and offshore waters occupied by approximately one million marine birds. More than 30,000 dead birds of 90 species were retrieved from polluted areas by 1 August 1989. Of those identified, murres (74%), other...
Authors
John F. Piatt, Calvin J. Lensink, William Butler, Marshal Kendziorek, David R. Nysewander