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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: 2891

Double-stocking for overcoming damage to conifer seedlings by pocket gophers

A 5-yr study was conducted on national forests in Idaho and Oregon to evaluate how doubling the seedling stocking rate of lodgepole pine (Pinus contorta) would relate to 5-year survival and the uniformity of distribution of seedlings in the presence of northern pocket gopher (Thomomys talpoides) damage. Either 4 or 8 seedlings were planted in 40-m2 subplots (1000 or 2000 seedlings/ha) and monitore
Authors
Richard M. Engeman, Richard M. Anthony, Victor G. Barnes, Heather W. Krupa, James Evans

Electrocardiographic consequences of a peripatetic lifestyle in gray wolves (Canis lupus)

Cardiac chamber enlargement and hypertrophy are normal physiologic responses to repetitive endurance exercise activity in human beings and domestic dogs. Whether similar changes occur in wild animals as a consequence of increased activity is unknown. We found that free-ranging gray wolves (Canis lupus, n=11), the archetypical endurance athlete, have electrocardiographic evidence of cardiac chamber
Authors
Peter Constable, Ken Hinchcliff, Nick Demma, Margaret Callahan, Bruce W. Dale, Kevin Fox, Layne G. Adams, Ray Wack, Lynn Kramer

Certainty of paternity and paternal investment in eastern bluebirds and tree swallows

Extra-pair paternity is common in many socially monogamous passerine birds with biparental care. Thus, males often invest in offspring to which they are not related. Models of optimal parental investment predict that, under certain assumptions, males should lower their investment in response to reduced certainty of paternity. We attempted to reduce certainty of paternity experimentally in two spec
Authors
Bart Kempenaers, Richard B. Lanctot, Raleigh J. Robertson

Male traits, mating tactics and reproductive success in the buff-breasted sandpiper, Tryngites subruficollis

Buff-breasted sandpipers use a variety of mating tactics to acquire mates, including remaining at a single lek for most of the breeding season, attending multiple leks during the season, displaying solitarily or displaying both on leks and solitarily. We found that differences in body size, body condition, fluctuating asymmetry scores, wing coloration, territory location and behaviour (attraction,
Authors
Richard B. Lanctot, Patrick J. Weatherhead, Bart Kempenaers, Kim T. Scribner

Chlorinated hydrocarbon contaminants in polar bears from eastern Russia, North America, Greenland, and Svalbard: Biomonitoring of Arctic pollution

Adipose tissue samples from polar bears (Ursus maritimus) were obtained by necropsy or biopsy between the spring of 1989 to the spring of 1993 from Wrangel Island in Russia, most of the range of the bear in North America, eastern Greenland, and Svalbard. Samples were divided into 16 regions corresponding as much as possible to known stocks or management zones. Concentrations of dieldrin (DIEL), 4,
Authors
R. J. Norstrom, Stanislav Belikov, E.W. Born, G.W. Garner, B. Malone, S. Olpinski, M.A. Ramsay, S. Schliebe, I. Stirling, M.S. Sitshov, M.K. Taylor, Øystein Wiig

Sedimentology, conodonts, structure, and correlation of Silurian and Devonian metasedimentary rocks in Denali National Park, Alaska: A section in Geologic studies in Alaska by the U.S. Geological Survey, 1996

A sequence of metasedimentary rocks in Denali National Park (Mt. McKinley and Healy quadrangles), previously mapped by Csejtey and others (1992) as unit DOs (Ordovician to Middle Devonian metasedimentary sequence) and correlated with rocks of the Nixon Fork terrane, contains both deep- and shallow-water facies that correlate best with rocks of the Dillinger and Mystic sequences (Farewell terrane),
Authors
Julie A. Dumoulin, Dwight Bradley, Anita G. Harris

Polar bears of the Severnaya Zemlya Archipelago of the Russian Arctic

No abstract available.
Authors
Stanislav Belikov, G.W. Garner, O. Wiig, Andrei N. Boltunov, Y.A. Gorbunov

Serum biochemistry of captive and free-ranging gray wolves (Canis lupus)

Normal serum biochemistry values are frequently obtained from studies of captive sedentary (zoo) or free-ranging (wild) animals. It is frequently assumed that values from these two populations are directly referable to each other. We tested this assumption using 20 captive gray wolves (Canis lupus) in Minnesota, USA, and 11 free-ranging gray wolves in Alaska, USA. Free-ranging wolves had significa
Authors
Peter Constable, Ken Hinchcliff, Nick Demma, Margaret Callahan, B.W. Dale, Kevin Fox, Layne G. Adams, Ray Wack, Lynn Kramer

Reproductive performance of female Alaskan caribou

We examined the reproductive performance of female caribou (Rangifer tarandus granti) in relation to age, physical condition, and reproductive experience for 9 consecutive years (1987-95) at Denali National Park, Alaska, during a period of wide variation in winter snowfall. Caribou in Denali differed from other cervid populations where reproductive performance has been investigated, because they o
Authors
Layne G. Adams, Bruce W. Dale

Flow-cytometric determination of genotoxic effects of exposure to petroleum in mink and sea otters

Three experiments were conducted to investigate the genotoxic effects of crude oil on mink and sea otters, In the first experiment, the effects on mink of chronic exposure to weathered Prudhoe Bay crude oil were studied, Female mink were fed a diet that included weathered crude oil for a period of 3 weeks prior to mating, during pregnancy and until weaning. Kits were exposed through lactation and
Authors
J. W. Bickham, J.A. Mazet, J. Blake, M.J. Smolen, Y. Lou, Brenda E. Ballachey

Timing and synchrony of parturition in Alaska caribou

Timing of parturition of caribou (Rangifer tarandus) varies within populations, but the relative influences of nutritional condition of females during the autumn breeding season and during gestation on that variation is not known. We determined timing of parturition of caribou in Denali National Park, Alaska, during 1984–1995, which had wide variation in snowfall that influenced nutritional condit
Authors
Layne G. Adams, Bruce W. Dale

Dinucleotide repeat polymorphisms in waterfowl (family Anatidae): Characterization of a sex-linked (Z-specific) and 14 autosomal loci

Canada goose (Branta Canadensis) and harlequin duck (Histrionicus histrionicus) DNAs were digested with Sau3AI, and size selected (300-700 bp) fragments were ligated into BamHI-digested pBluscriptII KS+. The enrichment protocol of Ostrander et al.1 was followed. The resulting libraries were screened using a [ƴ-32P]ATP end-labelled (CA)20 oligonucleotides as a hybridization probe. Positive clones w
Authors
W.G. Buchholz, John M. Pearce, Barbara J. Pierson, Kim T. Scribner