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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: 1334

Grizzly bear denning chronology and movements in the Greater Yellowstone Ecosystem Grizzly bear denning chronology and movements in the Greater Yellowstone Ecosystem

Den entrance and emergence dates of grizzly bears (Ursus arctos) in the Greater Yellowstone Ecosystem are important to management agencies that wish to minimize impacts of human activities on bears. Current estimates for grizzly bear denning events use data that were collected from 1975–80. We update these estimates by including data obtained from 1981–99. We used aerial telemetry data...
Authors
Mark A. Haroldson, Mark A. Ternent, Kerry A. Gunther, Charles C. Schwartz

Effectiveness of Brucella abortus Strain 19 single calfhood vaccination in elk (Cervus elaphus) Effectiveness of Brucella abortus Strain 19 single calfhood vaccination in elk (Cervus elaphus)

Brucellosis in Greater Yellowstone Area (GYA) bison and elk has been a source of controversy and focus of the Greater Yellowstone Interagency Brucellosis Committee (GYIBC) for years. Brucellosis has been eradicated from cattle in the 3 states of Wyoming, Montana, and Idaho and all three states currently are classified as “brucellosis free” with regard to livestock. Yet free-ranging elk...
Authors
Thomas J. Roffe, Lee C. Jones, Kenneth Coffin, Steven J. Sweeney

Responses of Florida panthers to recreational deer and hog hunting Responses of Florida panthers to recreational deer and hog hunting

Big Cypress National Preserve constitutes approximately one-third of the range of the endangered Florida panther (Puma concolor coryi). Because recreational hunting is allowed in Big Cypress National Preserve, we examined 8 response variables (activity rates, movement rates, predation success, home-range size, home-range shifts, proximity to off-road vehicle trails, use of areas with...
Authors
Michael W. Janis, Joseph D. Clark

Aerial survey methodology for bison population estimation in Yellowstone National Park Aerial survey methodology for bison population estimation in Yellowstone National Park

I developed aerial survey methods for statistically rigorous bison population estimation in Yellowstone National Park to support sound resource management decisions and to understand bison ecology. Survey protocols, data recording procedures, a geographic framework, and seasonal stratifications were based on field observations from February 1998-September 2000. The reliability of this...
Authors
Steven C. Hess

The paradigm of grizzly bear restoration in North America The paradigm of grizzly bear restoration in North America

Grizzly bear restoration and recovery is a controversial, highly politicized process. By 1959, when the Craigheads began their pioneering work on Yellowstone grizzly bears, the species had been reduced to a remnant of its historic range. Prior to the colonization of North America by Europeans, the grizzly lived in relatively pristine habitats with aboriginal Native Americans. As...
Authors
C. C. Schwartz

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
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