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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: 1197

A model to predict the occurrence of surviving butternut trees in the southern Appalachian region: Chapter 43

No abstract available.
Authors
Frank T. van Manen, Joseph D. Clark, Scott E. Schlarbaum, Kristine D. Johnson, Glenn Taylor

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 designed to
Authors
Rick Eastridge, Joseph D. Clark

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 concentrated
Authors
Michael W. Janis, Joseph D. Clark

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 Act establi
Authors
B. Bohn, J. L. Kershner

Variable breeding phenology affects the exposure of amphibian embryos to ultraviolet radiation

Reduced water depth in dry years has been proposed to interact with ultraviolet- B (UV-B) radiation and a pathogenic fungus to cause episodes of high mortality of amphibian embryos. Observations of breeding phenology of boreal chorus frogs (Pseudacris maculata) in Colorado from 1986 to 2001 show that dry years result in earlier breeding. The earliest and latest dates of maximum calling activity by
Authors
P. S. Corn, E. Muths

Estimating the number of females with cubs-of-the-year in the Yellowstone grizzly bear population

No abstract available.
Authors
K.A. Keating, C.C. Schwartz, M.A. Haroldson, D. Moody

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 human-caused
Authors
S. Cherry, M.A. Haroldson, J. Robison-Cox, C.C. Schwartz

An application of queuing theory to waterfowl migration

There has always been great interest in the migration of waterfowl and other birds. We have applied queuing theory to modelling waterfowl migration, beginning with a prototype system for the Rocky Mountain Population of trumpeter swans (Cygnus buccinator) in Western North America. The queuing model can be classified as a D/BB/28 system, and we describe the input sources, service mechanism, and net
Authors
Richard S. Sojda, John E. Cornely, Leigh H. Fredrickson

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. The Kaml
Authors
Kathy L. Knudsen, Clint C. Muhlfeld, George K. Sage, Robb F. Leary

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 stored at
Authors
M.A. Murphy, L.P. Waits, K.C. Kendall, S.K. Wasser, J.A. Higbee, R. Bogden

Chronic Wasting Disease (CWD): Just the Facts

Chronic Wasting Disease (CWD) has appeared widely in the media lately, but has actually been around for a while. It was first recognized in Colorado in 1967, in a captive research herd of mule deer. Its rapid expansion, to include eight states and two provinces by the year 2002, has created a crisis.
Authors
Thomas J. Roffe, Dick Jachowski

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 civilization expan
Authors
C. C. Schwartz