Northern Rocky Mountain Science Center

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: 1,023
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Year Published: 1985

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...

Knight, Richard R.; Eberhardt, L.L.
Population dynamics of Yellowstone grizzly bears; 1985; Article; Journal; Ecology; Knight, Richard R.; Eberhardt, L. L.

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Year Published: 1983

Late Wisconsin mountain glaciation in the western United States

No abstract available.

Porter, S.C.; Pierce, Kenneth L.; Hamilton, T. D.

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Year Published: 1983

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...

Worley, David E.; Greer, Kenneth R.; Palmisciano, Daniel A.

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Year Published: 1983

Grizzly bear: habitat relationships in the Yellowstone area

Habitat use by grizzly bears (Ursus arctos) was studied from 1977 through 1979 in a 20,000-km2 area with Yellowstone National Park in the center. Of 1826 aerial radio locations of 46 instrumental grizzlies, 90% were in timber. Three-fourths of the locations were 100 m or less from an edge between timber and an opening. Timber over 3 m tall with a...

Blanchard, Bonnie M.
Grizzly bear: habitat relationships in the Yellowstone area; 1983; Article; Journal; Bears: Their Biology and Management; Blanchard, Bonnie M.

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Year Published: 1983

The relationship between parental age and reproductive effort in the California gull (Larus californicus)

Pugesek, B.H.
The relationship between parental age and reproductive effort in the California gull (Larus californicus); 1983; Article; Journal; Behavioral Ecology and Sociobiology; Pugesek, B. H.

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Year Published: 1980

Time-lapse cameras as an aid in studying grizzly bears in northwest Wyoming

Time-lapse cameras were effective for gathering limited distribution and population data on grizzly bears (Ursus arctos) and black bears (Ursus americanus) in northwest Wyoming. Thirty-six stations, each consisting of a camera and a lure, were monitored for 551 camera-days; 83 rolls of film were exposed. Five different lures were tested. Thirty-...

Ball, Ronald E.

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Year Published: 1980

Factors influencing human-grizzly bear interactions in a backcountry setting

Interactins between humans and 7 species of wildlife, including grizzly bears (Ursus arctos horribilis), were investigated in backcountry areas of the Gallatin Range, Yellowstone National Park, during the summers of 1973 and 1974. Grizzly bear distribution, movements, and behavior and human behavior were examined. Because grizzlies utilized areas...

Chester, James M.

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Year Published: 1980

Biological considerations in the delineation of critical habitat

Grizzly bears (Ursus arctos) require large areas to satisfy their needs for food, cover, and space. They thrive best where disturbance by man is minimal. It is not a coincidence that the two major grizzly bear populations in the lower 48 states exist in large wilderness systems closely associated with two large national parks and a relatively...

Knight, Richard R.

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Year Published: 1980

Movements of radio-instrumented grizzly bears within the Yellowstone area

Grizzly bear (Ursus arctos horribilis) movement patterns were studied with the aid of 18 radio-instrumented grizzly bears in 1975 and 1976. Five bears gave minimal information because of death, transmitter failure, or loss of transmitters. Seasonal home range information is presented for 13 bears. Two bears, trapped inside Yellowstone National...

Judd, Steven L.; Knight, Richard R.

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Year Published: 1980

The natural food habits of grizzly bears in Yellowstone National Park, 1973-74

 The natural food habits of grizzly bears (Ursus arctos horribilis Ord) in Yellowstone National Park were investigated in 1973-74 to identify the grizzly's energy sources and trophic level(s), nutrient use, and distribution. Food consumption was determined by scat analysis and field observations. Food quality and digestibility were estimated...

Mealey, Stephen Patrick

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Year Published: 1978

Climate and reproduction of grizzly bears in Yellowstone National Park

Controversy surrounds the conflicts between the requirements of human safety and the preservation of grizzly bears (Ursus arctos horribilis) in western North America. It has been difficult to separate the effect of factors such as the closure of garbage dumps from that of the climate. It has also proved difficult to relate climatic data to...

Picton, Harold D.