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Publications

Below is a list of available NOROCK peer reviewed and published science. If you are in search of a specific publication and cannot find it below or through a search, please contact twojtowicz@usgs.gov.

Filter Total Items: 1211

Bear use of cutthroat trout spawning streams in Yellowstone National Park

Grizzly bears (Ursus arctos) and black bears (U. americanus) prey on spawning cutthroat trout (Oncorhynchus clarki, formerly known as Salmo clarki) in tributary streams of Yellowstone Lake. These tributary streams were surveyed from 1985 to 1987 to determine the presence and level of trout spawning activity and bear use. Indices were developed to enumerate spawner density and levels of bear use. O
Authors
Daniel P. Reinhart, D.J. Mattson

Predatory behavior of grizzly bears feeding on elk calves in Yellowstone National Park

Grizzly bears (Ursus arctos horribilis) were observed preying on elk calves (Cervus elaphus) on 60 occasions in Yellowstone National Park, with 29 confirmed kills. Some bears were deliberate predators and effectively preyed on elk calves for short periods each spring, killing up to 1 calf daily. Primary hunting techniques were searching and chasing although some bears used a variety of techniques
Authors
Steven P. French, Marilynn G. French

Fluctuating asymmetry and testing isolation of Montana grizzly bear populations

Fluctuating asymmetry of adult skulls was used to test he genetic isolation of the Yellowstone grizzly bear population from its nearest neighbor. An overall summary statistic was used in addition to 16 other parameters. Tests found the males of the Yellowstone populaion to be more vaiable than those of the North Conitinental Divide Exosystem. Evidence for precipitaiton effects is also included. Th
Authors
Harold D. Picton, Daniel A. Palmisciano, Gerald Nelson

Mortality patterns and population sinks for Yellowstone grizzly bears, 1973-1985

No abstract available.
Authors
R. R. Knight, B.M. Blanchard, L. L. Eberhardt

Arkansas black bear hunter survey

Questionnaires were mailed to black bear (Ursus americanus) hunters in Arkansas following the 1980-84 bear seasons to determine participation, hunter success, and number of bears observed by hunters. Man-days of hunting to harvest a bear ranged from 148 to 671 and hunter success ranged from 0.4% to 2.2%. With the exception of 1980, number of permits issued, man-days of bear hunting, and bears harv
Authors
Larry D. Pharris, Joseph D. Clark

Glacial sequence near McCall, Idaho: Weathering rinds, soil development, morphology, and other relative-age criteria

The sequence of glacial deposits near McCall, Idaho, previously assigned to the Pinedale and Bull Lake glaciations, contains deposits of four different ages. These ages are defined by multiple relative-age criteria, including weathering rinds, soil development, surface-rock weathering, morainal morphology, and loess stratigraphy. The thickness of weathering rinds on basaltic clasts is statisticall
Authors
S.M. Colman, Kenneth L. Pierce

Population dynamics of Yellowstone grizzly bears

Data on the population of grizzly bears in the environs of Yellowstone National Park suggest that the population has not recovered from the reductions following closure of garbage dumps in 1970 and 1971, and may continue to decline. A computer simulation model indicates that the risk of extirpation over the next 30 yr is small, if the present population parameters continue to prevail. A review and
Authors
Richard R. Knight, L. L. Eberhardt

Late Wisconsin mountain glaciation in the western United States

No abstract available.
Authors
S.C. Porter, Kenneth L. Pierce, T. D. Hamilton

Possible relationships between trichinellosis and abnormal behavior in bears

Data compiled from parasite studies of grizzly bears (Ursus arctos) and black bears (U. americanus) in the Yellowstone and Glacier National Park populations and surrounding areas of Montana and Wyoming during 1969-79 are reviewed with reference to the possible influence of infection with the muscleworm Trichinella sp. on bear behavior. In grizzly bears, the high prevalence of this parasite (61% of
Authors
David E. Worley, Kenneth R. Greer, Daniel A. Palmisciano