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: 1216
Second chance for the plains bison
Before European settlement the plains bison (Bison bison bison) numbered in the tens of millions across most of the temperate region of North America. Within the span of a few decades during the mid- to late-1800s its numbers were reduced by hunting and other factors to a few hundred. The plight of the plains bison led to one of the first major movements in North America to save an endangered spec
Authors
Curtis H. Freese, K. Aune, D. Boyd, James N. Derr, Steven C. Forrest, C. Cormack Gates, Peter J. Gogan, Shaun M. Grassel, Natalie D. Halbert, Kyran Kunkel, Kent Redford
A simple solar radiation index for wildlife habitat studies
Solar radiation is a potentially important covariate in many wildlife habitat studies, but it is typically addressed only indirectly, using problematic surrogates like aspect or hillshade. We devised a simple solar radiation index (SRI) that combines readily available information about aspect, slope, and latitude. Our SRI is proportional to the amount of extraterrestrial solar radiation theoretica
Authors
Kim A. Keating, Peter J. Gogan, John N. Vore, Lynn R. Irby
The art and science of weed mapping
Land managers need cost-effective and informative tools for non-native plant species management. Many local, state, and federal agencies adopted mapping systems designed to collect comparable data for the early detection and monitoring of non-native species. We compared mapping information to statistically rigorous, plot-based methods to better understand the benefits and compatibility of the two
Authors
David T. Barnett, Thomas J. Stohlgren, Catherine S. Jarnevich, Geneva W. Chong, Jenny A. Ericson, Tracy R. Davern, Sara E. Simonson
Evaluating estimators for numbers of females with cubs-of-the-year in the Yellowstone grizzly bear population
Current management of the grizzly bear (Ursus arctos) population in Yellowstone National Park and surrounding areas requires annual estimation of the number of adult female bears with cubs-of-the-year. We examined the performance of nine estimators of population size via simulation. Data were simulated using two methods for different combinations of population size, sample size, and coefficient of
Authors
S. Cherry, G.C. White, K.A. Keating, Mark A. Haroldson, Charles C. Schwartz
Spatial population structure of Yellowstone bison
Increases in Yellowstone National Park, USA, bison (Bison bison) numbers and shifts in seasonal distribution have resulted in more frequent movements of bison beyond park boundaries and development of an interagency management plan for the Yellowstone bison population. Implementation of the plan under the adaptive management paradigm requires an understanding of the spatial and temporal structure
Authors
Edward M. Olexa, Peter J. Gogan
Identifying sites for elk restoration in Arkansas
We used spatial data to identify potential areas for elk (Cervus elaphus) restoration in Arkansas. To assess habitat, we used locations of 239 elk groups collected from helicopter surveys in the Buffalo National River area of northwestern Arkansas, USA, from 1992 to 2002. We calculated the Mahalanobis distance (D2) statistic based on the relationship between those elk-group locations and a suite o
Authors
R.L. Telesco, F.T. Van Manen, J. D. Clark, Michael E. Cartwright
Alpine ecosystem dynamics and change: A view from the heights
No abstract available.
Authors
G.P. Malanson, D.R. Butler, Daniel B. Fagre
Modeling and monitoring biophysical dynamics and change
No abstract available.
Authors
Daniel B. Fagre
Response of western mountain ecosystems to climatic variability and change: The Western Mountain Initiative
Mountain ecosystems within our national parks and other protected areas provide valuable goods and services such as clean water, biodiversity conservation, and recreational opportunities, but their potential responses to expected climatic changes are inadequately understood. The Western Mountain Initiative (WMI) is a collaboration of scientists whose research focuses on understanding and predictin
Authors
Nathan L. Stephenson, David A. Peterson, Daniel B. Fagre, Craig D. Allen, Donald McKenzie, Jill Baron, K. O'Brien
Uncertainty management, spatial and temporal reasoning, and validation of intelligent environmental decision support systems
There are inherent open problems arising when developing and running Intelligent Environmental
Decision Support Systems (IEDSS). During daily operation of IEDSS several open challenge problems
appear. The uncertainty of data being processed is intrinsic to the environmental system, which is being
monitored by several on-line sensors and off-line data. Thus, anomalous data values at data gatheri
Authors
Miquel Sànchez-Marrè, Karina Gilbert, Rick S. Sojda, Jean Philippe Steyer, Peter Struss, Ignasi Rodríguez-Roda