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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: 1302

Estimating total human-caused mortality from reported mortality using data from radio-instrumented grizzly bears Estimating total human-caused mortality from reported mortality using data from radio-instrumented grizzly bears

Tracking mortality of the Yellowstone grizzly bear (Ursus arctos horribilis) is an essential issue of the recovery process. Problem bears removed by agencies are well documented. Deaths of radiocollared bears are known or, in many cases, can be reliably inferred. Additionally, the public reports an unknown proportion of deaths of uncollared bears. Estimating the number of non-agency...
Authors
S. Cherry, M.A. Haroldson, J. Robison-Cox, C.C. Schwartz

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

A half century of change in alpine treeline patterns at Glacier National Park, Montana, U.S.A. A half century of change in alpine treeline patterns at Glacier National Park, Montana, U.S.A.

Using sequential aerial photography, we identified changes in the spatial distribution of subalpine fir (Abies lasiocarpa) habitat at the alpine treeline ecotone. Six 40-ha study sites in the McDonald Creek drainage of Glacier National Park contained subalpine fir forests that graded into alpine tundra. Over a 46-yr period, altitudinal changes in the location of alpine treeline ecotone...
Authors
F.L. Klasner, D.B. Fagre

An evaluation of long-term preservation methods for brown bear (Ursus arctos) faecal DNA samples An evaluation of long-term preservation methods for brown bear (Ursus arctos) faecal DNA samples

Relatively few large-scale faecal DNA studies have been initiated due to difficulties in amplifying low quality and quantity DNA template. To improve brown bear faecal DNA PCR amplification success rates and to determine post collection sample longevity, five preservation methods were evaluated: 90% ethanol, DETs buffer, silica-dried, oven-dried stored at room temperature, and oven-dried...
Authors
M.A. Murphy, L.P. Waits, K.C. Kendall, S.K. Wasser, J.A. Higbee, R. Bogden

Tolazoline reversal of xylazine in bison (Bison bison): Mitigation of adverse effects Tolazoline reversal of xylazine in bison (Bison bison): Mitigation of adverse effects

Tolazoline is a mixed alpha-1 and -2 adrenergic antagonist used to reverse the sedative, analgesic and muscle-relaxing effects of xylazine, a potent alpha adrenergic agonist. Tolazoline has been used in cattle and is superior to yohimbine, another alpha adrenergic antagonist, in this species. In white-tailed deer, tolazoline shortened recovery times and reversed xylazine-induced...
Authors
Thomas J. Roffe, Steven J. Sweeney

Establishing aquatic restoration priorities using a watershed approach Establishing aquatic restoration priorities using a watershed approach

Since the passage of the Clean Water Act in 1972, the United States has made great strides to reduce the threats to its rivers, lakes, and wetlands from pollution. However, despite our obvious successes, nearly half of the nation’s surface water resources remain incapable of supporting basic aquatic values or maintaining water quality adequate for recreational swimming. The Clean Water...
Authors
B. Bohn, J. L. Kershner

Hydrologic processes and nutrient dynamics in a pristine mountain catchment Hydrologic processes and nutrient dynamics in a pristine mountain catchment

Nutrient dynamics in watersheds have been used as an ecosystem-level indicator of overall ecosystem function or response to disturbance (e.g. Borman.N et al. 1974, WEBSTER et al. 1992). The examination of nutrients has been evaluated to determine responses to logging practices or other changes in watershed land use. Nutrient dynamics have been related to changing physical and biological
Authors
F. Richard Hauer, Daniel B. Fagre, Jack A. Stanford

Spawning characteristics of redband trout in a headwater stream in Montana Spawning characteristics of redband trout in a headwater stream in Montana

I investigated the spawning characteristics of redband trout Oncorhynchus mykiss gairdneri (a rainbow trout subspecies) during the spring of 1998 in Basin Creek, a third-order headwater stream located in the Kootenai River drainage in northwestern Montana. I examined the timing of spawning as related to discharge and water temperature and analyzed microhabitat selection of 30 completed...
Authors
Clint C. Muhlfeld

Evaluation of 2-soft-release techniques to reintroduce black bears Evaluation of 2-soft-release techniques to reintroduce black bears

Black bear (Ursus americanus) were extirpated from most of their range by the early 1900s by habitat destruction and unregulated hunting. Since then, bear habitat has recovered in many areas, but isolation may prevent natural recolonization. Black bear translocations often have limited success because of high mortality rates and low site fidelity. We tested 2 reintroduction techniques...
Authors
Rick Eastridge, Joseph D. Clark
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