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: 1222
Dispersal ecology of lodgepole pine (Pinus contorta Dougl.) in its native environment as related to Swedish forestry
Lodgepole pine (Pinus contorta Dougl.) covers extensive areas of the mountains of western North America. It has evolved into four subspecies, each adapted to slightly different environmental conditions. All are adapted to reproduce following fire. Subspecies latifolia is the most extensive and economically important in North America. Serotiny is common in this subspecies, but trees bearing nonsero
Authors
Don G. Despain
Field trials of line transect methods applied to estimation of desert tortoise abundance
We examine the degree to which field observers can meet the assumptions underlying line transect sampling to monitor populations of desert tortoises (Gopherus agassizii). We present the results of 2 field trials using artificial tortoise models in 3 size classes. The trials were conducted on 2 occasions on an area south of Las Vegas, Nevada, where the density of the test population was known. In t
Authors
David R. Anderson, Kenneth P. Burnham, Bruce C. Lubow, L. E. N. Thomas, Paul Stephen Corn, Philip A. Medica, R.W. Marlow
A framework for ecological decision support systems: Building the right systems and building the systems right
Workshops in the late 1990's launched the commitment of the U.S. Geological Survey's Biological Resources Division (BRD) to develop and implement decision support systems (DSS) applications. One of the primary goals of this framework document is to provide sufficient background and information for Department of the Interior (DOI) bureau stakeholders and other clients to determine the potential for
Authors
Frank D'Erchia, Carl E. Korschgen, M. Nyquist, Ralph Root, Richard S. Sojda, Peter Stine
Estimating numbers of females with cubs-of-the-year in the Yellowstone grizzly bear population
For grizzly bears (Ursus arctos horribilis) in the Greater Yellowstone Ecosystem (GYE), minimum population size and allowable numbers of human-caused mortalities have been calculated as a function of the number of unique females with cubs-of-the-year (FCUB) seen during a 3- year period. This approach underestimates the total number of FCUB, thereby biasing estimates of population size and sustaina
Authors
K.A. Keating, C.C. Schwartz, M.A. Haroldson, D. Moody
Spawning migration of lacustrine-adfluvial bull trout in a natural area
We investigated the spawning migration of lacustrine-adfluvial bull trout Salvelinus confluentus in the North Fork Skokomish River in Olympic National Park (Washington State) during 1996. Day-snorkeling and electrofishing were conducted to determine timing and duration of the migration and the distribution and abundance of bull trout. The primary spawning migration began in early October and was w
Authors
Samuel J. Brenkman, Gary L. Larson, Robert E. Gresswell
Experimental repatriation of boreal toad (Bufo boreas) eggs, metamorphs, and adults in Rocky Mountain National Park
The boreal toad (Bufo boreas) is an endangered species in Colorado and is considered a candidate species for federal listing by the United States Fish and Wildlife Service. Boreal toads are absent from many areas of suitable habitat in the Southern Rocky Mountains of Colorado presumably due to a combination of causes. We moved boreal toads from existing populations and from captive rearing facilit
Authors
E. Muths, T. L. Johnson, P. S. Corn
Florida panther habitat use response to prescribed fire
The Florida panther (Puma concolor coryi) is one of the most endangered mammals in the world, with only 30-50 adults surviving in and around Florida Panther National Wildlife Refuge and the adjacent Big Cypress National Preserve. Managers at these areas conduct annual prescribed burns in pine (Pinus sp.) as a cost-effective method of managing wildlife habitat. Our objectives were to determine if t
Authors
Catherine S. Dees, Joseph D. Clark, Frank T. van Manen
New approaches for sampling and modeling native and exotic plant species richness
No abstract available.
Authors
G.W. Chong, R.M. Reich, M. A. Kalkhan, T.J. Stohlgren
Evaluation of a GPS used in conjunction with aerial telemetry
We investigated the use of a non-correctable Global Positioning System (NGPS) in association with aerial telemetry to determine animal locations. Average error was determined for 3 components of the location process: use of a NGPS receiver on the ground, use of a NGPS receiver in a aircraft while flying over a visual marker, and use of the same receiver while flying over a location determined by s
Authors
E.M. Olexa, P.J.P. Gogan, K.M. Podruzny
Influence of basin and watershed characteristics on the nutrient chemistry of headwater streams in northern Idaho
No abstract available.
Authors
B. R. Hossack, S.M. Struhs, K. Lohman
Pathology of brucellosis in bison from Yellowstone National Park
Between February 1995 and June 1999, specimens from seven aborted bison (Bison bison) fetuses or stillborn calves and their placentas, two additional placentas, three dead neonates, one 2-wk-old calf, and 35 juvenile and adult female bison from Yellowstone National Park (USA) were submitted for bacteriologic and histopathologic examination. One adult animal with a retained placenta had recently ab
Authors
Jack C. Rhyan, T. Gidlewski, T.J. Roffe, K. Aune, L.M. Philo, D.R. Ewalt
On-line sulfur isotope analysis of organic material by direct combustion: Preliminary results and potential applications
Sulfur isotopes have received little attention in ecology studies because plant and animal materials typically have low sulfur concentrations (< 1 wt.%) necessitating labor-intensive chemical extraction prior to analysis. To address the potential of direct combustion of organic material in an elemental analyzer coupled with a mass spectrometer, we compared results obtained by direct combustion to
Authors
C.L. Kester, R. O. Rye, C.A. Johnson, C.H. Schwartz, C.H. Holmes