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: 990
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Year Published: 1999

Predicting mountain lion activity using radiocollars equipped with mercury tip-sensors

Radiotelemetry collars with tip-sensors have long been used to monitor wildlife activity. However, comparatively few researchers have tested the reliability of the technique on the species being studied. To evaluate the efficacy of using tip-sensors to assess mountain lion (Puma concolor) activity, we radiocollared 2 hand-reared mountain lions and...

Janis, Michael W.; Clark, Joseph D.; Johnson, Craig

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Year Published: 1999

Role of brown bears (Ursus arctos) in the flow of marine nitrogen into a terrestrial ecosystem

We quantified the amount, spatial distribution, and importance of salmon (Oncorhynchus spp.)-derived nitrogen (N) by brown bears (Ursus arctos) on the Kenai Peninsula, Alaska. We tested and confirmed the hypothesis that the stable isotope signature (δ15N) of N in foliage of white spruce (Picea glauca) was inversely proportional to the...

Hilderbrand, Grant V.; Hanley, Thomas A.; Robbins, Charles T.; Schwartz, C.C.

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Year Published: 1999

Effects of sample size and sampling frequency on studies of brown bear home ranges and habitat use

We equipped 9 brown bears (Ursus arctos) on the Kenai Peninsula, Alaska, with collars containing both conventional very-high-frequency (VHF) transmitters and global positioning system (GPS) receivers programmed to determine an animal's position at 5.75-hr intervals. We calculated minimum convex polygon (MCP) and fixed and adaptive kernel home...

Arthur, Steve M.; Schwartz, Charles C.

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Year Published: 1999

Effect of seasonal differences in dietary meat intake on changes in body mass and composition in wild and captive brown bears

The influence of seasonal dietary meat intake on changes in body mass and composition in wild and captive brown bears (Ursus arctos) was investigated because the importance and availability of meat to brown bear populations is currently an important management consideration in several North American ecosystems. Adult female brown bears on the...

Hilderbrand, Grant V.; Jenkins, S.G.; Schwartz, C.C.; Hanley, Thomas A.; Robbins, C.T.

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Year Published: 1999

Radio-tracking large wilderness mammals: integration of GPS and Argos technologies

We tested 30 prototype global positioning system (GPS) radiocollars on brown bears (Ursus arctos) over a 3-year period on the Kenai Peninsula, Alaska. Collars were of 2 design types: GPS units with an Argos (Argos Data collection and Location System) satellite uplink (n = 19) and GPS units where the data were stored on board (n = 10) for retrieval...

Schwartz, Charles C.; Arthur, Steve M.

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Year Published: 1999

Yellowstone bears

No abstract available.

Clark, T.W.; Curlee, A.P.; Minta, S.C.; Kareiva, P.; Knight, R.R.; Blanchard, B.M.; Schullery, P.

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Year Published: 1999

Fire, red squirrels, whitebark pine, and Yellowstone grizzly bears

Whitebark pine (Pinus albicaulis) habitats are important to Yellowstone grizzly bears (Ursus arctos) as refugia and sources of food. Ecological relationships between whitebark pine, red squirrels (Tamiasciurus hudsonicus), and grizzly bear use of pine seeds on Mt. Washburn in Yellowstone National Park, Wyoming, were examined during 1984-86....

Podruzny, Shannon; Reinhart, Daniel P.; Mattson, David J.

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Year Published: 1999

Simulation of the potential responses of regional climate and surface processes in western North America to a canonical Heinrich event

No abstract available.

Clark, Peter U.; Webb, Robert S.; Keigwin, Lloyd D.; Hostetler, S. W.; Bartlein, P. J.

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Year Published: 1999

Radiotracking large wilderness mammals: Integration of GPS and Argos technology

We tested 30 prototype global positioning system (GPS) radiocollars on brown bears (Ursus arctos) over a 3-year period on the Kenai Peninsula, Alaska. Collars were of 2 design types: GPS with an Argos (Argos Data collection and Location System) satellite uplink (n=19) and GPS unites where the data were stored on board (n=10) for retrieval at a...

Schwartz, Charles C.; Arthur, Steve M.

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Year Published: 1999

Conservation endocrinology: A noninvasive tool to understand relationships between carnivore colonization and ecological carrying capacity

Reproductive technology, especially the diagnosis of pregnancy by radioimmunoassay of fecal steroid metabolites, is an important component of captive propagation, but its role in our understanding of ecological interactions and in situ biological restoration has been more limited. Where large herbivores have been 'released' from predation by the...

Berger, J.; Testa, J.W.; Roffe, T.; Monfort, S.L.
Conservation endocrinology: A noninvasive tool to understand relationships between carnivore colonization and ecological carrying capacity; 1999; Article; Journal; Conservation Biology; Berger, J.; Testa, J. W.; Roffe, T.; Monfort, S. L.

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Year Published: 1999

Exotic plant species invade hot spots of native plant diversity

Some theories and experimental studies suggest that areas of low plant species richness may be invaded more easily than areas of high plant species richness. We gathered nested-scale vegetation data on plant species richness, foliar cover, and frequency from 200 1-m2 subplots (20 1000-m2 modified-Whittaker plots) in the Colorado Rockies (USA), and...

Stohlgren, T.J.; Binkley, Dan; Chong, G.W.; Kalkhan, M.A.; Schell, L.D.; Bull, K.A.; Otsuki, Yuka; Newman, G.; Bashkin, Michael A.; Son, Y.
Exotic plant species invade hot spots of native plant diversity; 1999; Article; Journal; Ecological Monographs; Stohlgren, T. J.; Binkley, D.; Chong, G. W.; Kalkhan, M. A.; Schell, L. D.; Bull, K. A.; Otsuki, Y.; Newman, G.; Bashkin, M.; Son, Y.

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Year Published: 1999

Fire and aquatic ecosystems in forested biomes of North America

Gresswell, R.E.
Fire and aquatic ecosystems in forested biomes of North America; 1999; Article; Journal; Transactions of the American Fisheries Society; Gresswell, R. E.