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: 1334
Influence of barriers to movement on within-watershed genetic variation of coastal cutthroat trout Influence of barriers to movement on within-watershed genetic variation of coastal cutthroat trout
Because human land use activities often result in increased fragmentation of aquatic and terrestrial habitats, a better understanding of the effects of fragmentation on the genetic heterogeneity of animal populations may be useful for effective management. We used eight microsatellites to examine the genetic structure of coastal cutthroat trout (Oncorhynchus clarki clarki) in Camp Creek...
Authors
John E. B. Wofford, Robert E. Gresswell, Michael A. Banks
Topography and vegetation as predictors of snow water equivalent across the alpine treeline ecotone at Lee Ridge, Glacier National Park, Montana, U.S.A. Topography and vegetation as predictors of snow water equivalent across the alpine treeline ecotone at Lee Ridge, Glacier National Park, Montana, U.S.A.
We derived and implemented two spatial models of May snow water equivalent (SWE) at Lee Ridge in Glacier National Park, Montana. We used the models to test the hypothesis that vegetation structure is a control on snow redistribution at the alpine treeline ecotone (ATE). The statistical models were derived using stepwise and “best” subsets regression techniques. The first model was...
Authors
C. A. Geddes, Daniel G. Brown, Daniel B. Fagre
Estimated ultraviolet radiation doses in wetlands in six national parks Estimated ultraviolet radiation doses in wetlands in six national parks
Ultraviolet-B radiation (UV-B, 280–320-nm wavelengths) doses were estimated for 1024 wetlands in six national parks: Acadia (Acadia), Glacier (Glacier), Great Smoky Mountains (Smoky), Olympic (Olympic), Rocky Mountain (Rocky), and Sequoia/Kings Canyon (Sequoia). Estimates were made using ground-based UV-B data (Brewer spectrophotometers), solar radiation models, GIS tools, field...
Authors
S. A. Diamond, P.C. Trenham, M. J. Adams, B. R. Hossack, R.A. Knapp, L. Stark, D. Bradford, P.S. Corn, K. Czarnowski, P. D. Brooks, D.B. Fagre, B. Breen, N.E. Dentenbeck, K. Tonnessen
High dispersal in a frog species suggests that it is vulnerable to habitat fragmentation High dispersal in a frog species suggests that it is vulnerable to habitat fragmentation
Global losses of amphibian populations are a major conservation concern and their causes have generated substantial debate. Habitat fragmentation is considered one important cause of amphibian decline. However, if fragmentation is to be invoked as a mechanism of amphibian decline, it must first be established that dispersal is prevalent among contiguous amphibian populations using formal...
Authors
W.C. Funk, A.E. Greene, P.S. Corn, F.W. Allendorf
National parks and protected areas: Appoaches for balancing social, economic, and ecological values National parks and protected areas: Appoaches for balancing social, economic, and ecological values
The balance of nature in any strict sense has been upset long ago…The only option we have is to create a new balance objectively determined for each area in accordance with the intended use of that area.” --Aldo Leopold, 1927, in a letter to the Superintendent of Glacier National Park The planning and management staff of state/national parks and protected areas face a complex set of...
Authors
Tony Prato, Daniel B. Fagre
Evaluating single-pass catch as a tool for identifying spatial pattern in fish distribution Evaluating single-pass catch as a tool for identifying spatial pattern in fish distribution
We evaluate the efficacy of single-pass electrofishing without blocknets as a tool for collecting spatially continuous fish distribution data in headwater streams. We compare spatial patterns in abundance, sampling effort, and length-frequency distributions from single-pass sampling of coastal cutthroat trout (Oncorhynchus clarki clarki) to data obtained from a more precise multiple-pass...
Authors
Douglas S. Bateman, Robert E. Gresswell, Christian E. Torgersen
Evaluating mixed samples as a source of error in non-invasive genetic studies using microsatellites Evaluating mixed samples as a source of error in non-invasive genetic studies using microsatellites
The use of noninvasive genetic sampling (NGS) for surveying wild populations is increasing rapidly. Currently, only a limited number of studies have evaluated potential biases associated with NGS. This paper evaluates the potential errors associated with analysing mixed samples drawn from multiple animals. Most NGS studies assume that mixed samples will be identified and removed during...
Authors
David A. Roon, M.E. Thomas, K.C. Kendall, L.P. Waits
Status of amphibians on the Continental Divide:Surveys on a transect from Montana to Colorado, USA Status of amphibians on the Continental Divide:Surveys on a transect from Montana to Colorado, USA
The Rocky Mountain Region of the United States Geological Survey's Amphibian Research and Monitoring Initiative is conducting monitoring of the status of amphibians on a transect that extends along the Continental Divide from Canada to Colorado and comprises four National Parks. Monitoring uses visual encounter surveys to determine site occupancy, with multiple visits to a subset of...
Authors
P.S. Corn, B. R. Hossack, E. Muths, D.A. Patla, C.R. Peterson, Alisa L. Gallant
Spatial and temporal variability in the amount and source of dissolved organic carbon: Implications for ultraviolet exposure in amphibian habitats Spatial and temporal variability in the amount and source of dissolved organic carbon: Implications for ultraviolet exposure in amphibian habitats
The amount, chemical composition, and source of dissolved organic carbon (DOC), together with in situ ultraviolet (UV-B) attenuation, were measured at 1–2 week intervals throughout the summers of 1999, 2000, and 2001 at four sites in Rocky Mountain National Park (Colorado). Eight additional sites, four in Sequoia and Kings Canyon National Park/John Muir Wilderness (California) and four...
Authors
P. D. Brooks, C. M. O’Reilly, S. A. Diamond, K. Campbell, R. Knapp, D. Bradford, P.S. Corn, B. Hossack, K. Tonnessen
Factors affecting settling, survival, and viability of black bears reintroduced to Felsenthal National Wildlife Refuge, Arkansas Factors affecting settling, survival, and viability of black bears reintroduced to Felsenthal National Wildlife Refuge, Arkansas
We used radiotelemetry and population modeling techniques to examine factors related to population establishment of black bears (Ursus americanus) reintroduced to Felsenthal National Wildlife Refuge (NWR), Arkansas. Our objectives were to determine whether settling (i.e., establishment of a home range at or near the release site), survival, recruitment, and population viability were...
Authors
B.J. Wear, R. Eastridge, J. D. Clark
Climate change and amphibians Climate change and amphibians
Amphibian life histories are exceedingly sensitive to temperature and precipitation, and there is good evidence that recent climate change has already resulted in a shift to breeding earlier in the year for some species. There are also suggestions that the recent increase in the occurrence of El Niño events has caused declines of anurans in Central America and is linked to elevated...
Authors
P.S. Corn
Short-term responses of desert soil and vegetation to removal of feral burros and domestic cattle (California) Short-term responses of desert soil and vegetation to removal of feral burros and domestic cattle (California)
No abstract available.
Authors
Erik A. Beever, David A. Pyke