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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: 1316

Consumption of fungal sporocarps by Yellowstone grizzly bears Consumption of fungal sporocarps by Yellowstone grizzly bears

Sign of grizzly bears (Ursus arctos horribilis) consuming fungal sporocarps (mushrooms and truffles) was observed on 68 occasions during a study of radiomarked bears in the Yellowstone region, 1977–96. Sporocarps also were detected in 96 grizzly bear feces. Most fungi consumedby Yellowstone's grizzlybearsweremembersofthe Boletaceae(Suillus spp.), Russulaceae (Russula spp. and Lactarius...
Authors
David J. Mattson, Shannon Podruzny, Mark A. Haroldson

Genetic structure of Columbia River redband trout populations in the Kootenai River drainage, Montana, revealed by microsatellite and allozyme loci Genetic structure of Columbia River redband trout populations in the Kootenai River drainage, Montana, revealed by microsatellite and allozyme loci

We describe the genetic divergence among 10 populations of redband trout Oncorhynchus mykiss gairdneri from the upper Columbia River drainage. Resident redband trout from two watersheds in the Kootenai River drainage and hatchery stocks of migratory Kamloops redband trout from Kootenay Lake, British Columbia, were analyzed using allele frequency data from microsatellite and allozyme loci...
Authors
Kathy L. Knudsen, Clint C. Muhlfeld, George K. Sage, Robb F. Leary

Perspectives from the Aldo Leopold Wilderness Research Institute: Amphibians and wilderness Perspectives from the Aldo Leopold Wilderness Research Institute: Amphibians and wilderness

The decline of amphibian species has emerged as a major global conservation issue in the last decade. Last year, the Department of the Interior (DOI) initiated a major national initiative to detect trends in amphibian populations and research the causes of declines. The program, conducted principally by the U.S. Geological Survey (USGS), emphasizes lands managed by DOI, but collaboration...
Authors
Paul Stephen Corn

Freshwater forcing of abrupt climate change during the last glaciation Freshwater forcing of abrupt climate change during the last glaciation

Large millennial-scale fluctuations of the southern margin of the North American Laurentide Ice Sheet occurred during the last deglaciation, when the margin was located between about 43° and 49°N. Fluctuations of the ice margin triggered episodic increases in the flux of freshwater to the North Atlantic by rerouting continental runoff from the Mississippi River drainage to the Hudson or...
Authors
Peter U. Clark, Shawn J. Marshall, Garry K. C. Clarke, Steven W. Hostetler, Joseph M. Licciardi, James T. Teller

Distribution of grizzly bears in the Greater Yellowstone Ecosystem, 1990-2000 Distribution of grizzly bears in the Greater Yellowstone Ecosystem, 1990-2000

The Yellowstone grizzly bear (Ursus arctos horribilis) has been expanding its range during the past 2 decades and now occupies historic habitats that had been vacant. A current understanding of the distribution of grizzly bears within the ecosystem is useful in the recovery process and to help guide the state and federal land management agencies and state wildlife agencies of Idaho...
Authors
Charles C. Schwartz, Mark A. Haroldson, Kerry A. Gunther, D. Moody

Fall and winter habitat use and movement by Columbia River redband trout in a small stream in Montana Fall and winter habitat use and movement by Columbia River redband trout in a small stream in Montana

We used radiotelemetry to quantify the movements and habitat use of resident adult Columbia River redband trout Oncorhynchus mykiss gairdneri (hereafter, redband trout) from October to December 1997 in South Fork Callahan Creek, a third‐order tributary to Callahan Creek in the Kootenai River drainage in northwestern Montana. All redband trout (N = 23) were consistently relocated in a...
Authors
Clint C. Muhlfeld, David H. Bennett, B. Marotz

Negative binomial models for abundance estimation of multiple closed populations Negative binomial models for abundance estimation of multiple closed populations

Counts of uniquely identified individuals in a population offer opportunities to estimate abundance. However, for various reasons such counts may be burdened by heterogeneity in the probability of being detected. Theoretical arguments and empirical evidence demonstrate that the negative binomial distribution (NBD) is a useful characterization for counts from biological populations with
Authors
Mark S. Boyce, Darry I. MacKenzie, Bryan F.J. Manly, Mark A. Haroldson, David W. Moody

Cosmogenic 3He and 10Be chronologies of the late Pinedale northern Yellowstone ice cap, Montana, USA Cosmogenic 3He and 10Be chronologies of the late Pinedale northern Yellowstone ice cap, Montana, USA

Cosmogenic 3He and 10Be ages measured on surface boulders from the moraine sequence deposited by the northern outlet glacier of the Yellowstone ice cap indicate that the outlet glacier reached its terminal position at 16.5 ± 0.4 3He ka and 16.2 ± 0.3 10Be ka, respectively. Concordance of these ages supports the scaled production rates used for 3He (118.6 ± 6.6 atoms · g−1 · yr−1) and...
Authors
Joseph M. Licciardi, P.U. Clark, Edward J. Brook, Kenneth L. Pierce, Mark D. Kurz, David Elmore, Pankaj Sharma

The introduction of nonnative fish into wilderness lakes: Good intentions, conflicting mandates, and unintended consequences The introduction of nonnative fish into wilderness lakes: Good intentions, conflicting mandates, and unintended consequences

Because they have the potential to provide the best remaining standards of relatively unmodified landscapes, protected areas in North America (such as wilderness areas and national parks) have tremendous ecological and scientific value (Cole and Landres 1996). Although the montane ecosystems of western North America are particularly well represented in this complex of protected lands...
Authors
Roland A. Knapp, Paul Stephen Corn, Daniel E. Schindler

Florida panther Florida panther

No abstract available.
Authors
Joseph D. Clark

Dispersal ecology of lodgepole pine (Pinus contorta Dougl.) in its native environment as related to Swedish forestry Dispersal ecology of lodgepole pine (Pinus contorta Dougl.) in its native environment as related to Swedish forestry

Lodgepole pine (Pinus contorta Dougl.) covers extensive areas of the mountains of western North America. It has evolved into four subspecies, each adapted to slightly different environmental conditions. All are adapted to reproduce following fire. Subspecies latifolia is the most extensive and economically important in North America. Serotiny is common in this subspecies, but trees...
Authors
Don G. Despain
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