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: 1357
Simulation of the potential responses of regional climate and surface processes in western North America to a canonical Heinrich event Simulation of the potential responses of regional climate and surface processes in western North America to a canonical Heinrich event
No abstract available.
Authors
S. W. Hostetler, P. J. Bartlein
Radiotracking large wilderness mammals: Integration of GPS and Argos technology 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 later date. All units also contained a...
Authors
Charles C. Schwartz, Steve M. Arthur
Conservation endocrinology: A noninvasive tool to understand relationships between carnivore colonization and ecological carrying capacity 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 extirpation of carnivores, controversy...
Authors
J. Berger, J.W. Testa, T. Roffe, S.L. Monfort
Species - and community- level responses to disturbance imposed by feral horse grazing and other management practices Species - and community- level responses to disturbance imposed by feral horse grazing and other management practices
No abstract available.
Authors
Erik A. Beever, Peter F. Advised by Brussard
Exotic plant species invade hot spots of native plant diversity 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 160 1-m2 subplots (16 1000-m2 plots) in...
Authors
T.J. Stohlgren, Dan Binkley, G.W. Chong, M. A. Kalkhan, L. D. Schell, K.A. Bull, Yuka Otsuki, G. Newman, Michael A. Bashkin, Y. Son
Predicting mountain lion activity using radiocollars equipped with mercury tip-sensors 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 simultaneously recorded their behavior...
Authors
Michael W. Janis, Joseph D. Clark, Craig Johnson
Estimating the effectiveness of further sampling inspecies inventories Estimating the effectiveness of further sampling inspecies inventories
Estimators of the number of additional species expected in the next Δn samples offer a potentially important tool for improving cost-effectiveness of species inventories but are largely untested. We used Monte Carlo methods to compare 11 such estimators, across a range of community structures and sampling regimes, and validated our results, where possible, using empirical data from...
Authors
Kim A. Keating, James F. Quinn, M.A. Ivie, L.L. Ivie
Assessing simulated ecosystem processes for climate variability research at Glacier National Park, USA Assessing simulated ecosystem processes for climate variability research at Glacier National Park, USA
Glacier National Park served as a test site for ecosystem analyses that involved a suite of integrated models embedded within a geographic information system. The goal of the exercise was to provide managers with maps that could illustrate probable shifts in vegetation, net primary production (NPP), and hydrologic responses associated with two selected climatic scenarios. The climatic...
Authors
Joseph D. White, Steven W. Running, Peter E. Thornton, Robert E. Keane, Kevin C. Ryan, Daniel B. Fagre, Carl H. Key
Management of a large carnivore: Black bear Management of a large carnivore: Black bear
No abstract available.
Authors
Joseph D. Clark, Michael R. Pelton
Estimating species richness: The Michaelis-Menten model revisited Estimating species richness: The Michaelis-Menten model revisited
The Michaelis-Menten model has been widely used to estimate the richness (S) of species pools, but is largely untested. We tested whether (1) species accumulation curves follow the form predicted by the model, (2) the model gives unbiased estimates (Ŝ and B̂, respectively) of S and of the sample size, B, needed to detect S/2 species, and (3) performance is robust to community structure...
Authors
K.A. Keating, J.F. Quinn
Browse Evaluation by Analysis of Growth Form Browse Evaluation by Analysis of Growth Form
Abstract has not been submitted
Authors
R.B. Keigley, M.R. Frisina
Species repatriation: Red wolf Species repatriation: Red wolf
No abstract available.
Authors
C. F. Lucash, B. A. Crawford, J. D. Clark