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: 1220
Fire effects on aquatic ecosystems: an assessment of the current state of the science
Fire is a prevalent feature of many landscapes and has numerous and complex effects on geological, hydrological, ecological, and economic systems. In some regions, the frequency and intensity of wildfire have increased in recent years and are projected to escalate with predicted climatic and landuse changes. In addition, prescribed burns continue to be used in many parts of the world to clear vege
Authors
Rebecca J. Bixby, Scott D. Cooper, Robert E. Gresswell, Lee E. Brown, Clifford N. Dahm, Clifford N. Dahm, Kathleen A. Dwire
Spawning and rearing behavior of bull trout in a headwater lake ecosystem
Numerous life histories have been documented for bull trout Salvelinus confluentus. Lacustrine-adfluvial bull trout populations that occupy small, headwater lake ecosystems and migrate short distances to natal tributaries to spawn are likely common; however, much of the research on potamodromous bull trout has focused on describing the spawning and rearing characteristics of bull trout populations
Authors
Lora B. Tennant, Robert E. Gresswell, Christopher S. Guy, Michael H. Meeuwig
Fat, weather, and date affect migratory songbirds’ departure decisions, routes, and time it takes to cross the Gulf of Mexico
Approximately two thirds of migratory songbirds in eastern North America negotiate the Gulf of Mexico (GOM), where inclement weather coupled with no refueling or resting opportunities can be lethal. However, decisions made when navigating such features and their consequences remain largely unknown due to technological limitations of tracking small animals over large areas. We used automated radio
Authors
Jill L. Deppe, Michael P. Ward, Rachel T. Bolus, Robert H. Diehl, A. Celis-Murillo, Theodore J. Zenzal, Frank R. Moore, Thomas J. Benson, Jaclyn A. Smolinsky, Lynn N. Schofield, David A. Enstrom, Eben H. Paxton, Gil Bohrer, Tara A. Beveroth, Arlo Raim, Renee L. Obringer, David Delaney, William W. Cochran
Density dependence, whitebark pine, and vital rates of grizzly bears
Understanding factors influencing changes in population trajectory is important for effective wildlife management, particularly for populations of conservation concern. Annual population growth of the grizzly bear (Ursus arctos) population in the Greater Yellowstone Ecosystem, USA has slowed from 4.2–7.6% during 1983–2001 to 0.3–2.2% during 2002–2011. Substantial changes in availability of a key f
Authors
Frank T. van Manen, Mark A. Haroldson, Daniel D. Bjornlie, Michael R. Ebinger, Daniel J. Thompson, Cecily M. Costello, Gary C. White
Multiple estimates of effective population size for monitoring a long-lived vertebrate: An application to Yellowstone grizzly bears
Effective population size (Ne) is a key parameter for monitoring the genetic health of threatened populations because it reflects a population's evolutionary potential and risk of extinction due to genetic stochasticity. However, its application to wildlife monitoring has been limited because it is difficult to measure in natural populations. The isolated and well-studied population of grizzly bea
Authors
Pauline L. Kamath, Mark A. Haroldson, Gordon Luikart, David Paetkau, Craig L. Whitman, Frank T. van Manen
Effects of hybridization between nonnative Rainbow Trout and native Westslope Cutthroat Trout on fitness-related traits
Hybridization between introduced and native fauna is a risk to native species and may threaten the long-term persistence of numerous taxa. Rainbow Trout Oncorhynchus mykiss has been one of the most widely introduced species around the globe and often hybridizes with native Cutthroat Trout O. clarkii in the Rocky Mountains. Previous work has shown that hybridization negatively affects reproductive
Authors
Daniel P. Drinan, Molly A. H. Webb, Kerry A. Naish, Steven T. Kalinowski, Matthew C. Boyer, Amber C. Steed, Bradley B. Shepard, Clint C. Muhlfeld
Long term changes in trout numbers following channel reconstruction, instream wood placement, and livestock removal from a spring creek in the Blackfoot Basin, Montana
To restore habitat for wild trout, Kleinschmidt Creek, a low-gradient, groundwater-dominated stream in the Blackfoot Basin, Montana, was reconstructed using natural channel design principles. Reconstruction increased stream sinuosity from a ratio of 1.1 to 1.6, decreased mean channel width from 14.5 to 2.8 m, and increased sediment transport capacity to reduce accumulations of fine instream sedime
Authors
Ron Pierce, Craig Podner, Leslie A. Jones
Spatial occupancy models for predicting metapopulation dynamics and viability following reintroduction
The reintroduction of a species into its historic range is a critical component of conservation programmes designed to restore extirpated metapopulations. However, many reintroduction efforts fail, and the lack of rigorous monitoring programmes and statistical models have prevented a general understanding of the factors affecting metapopulation viability following reintroduction.
Spatially explic
Authors
Richard B. Chandler, Erin L. Muths, Brent H. Sigafus, Cecil R. Schwalbe, Christopher J. Jarchow, Blake R. Hossack
Too hot to trot? evaluating the effects of wildfire on patterns of occupancy and abundance for a climate-sensitive habitat-specialist
Wildfires are increasing in frequency and severity as a result of climate change in many ecosystems; however, effects of altered disturbance regimes on wildlife remain poorly quantified. Here, we leverage an unexpected opportunity to investigate how fire affects the occupancy and abundance of a climate-sensitive habitat specialist, the American pika (Ochotona princeps). We determine the effects of
Authors
Johanna Varner, Mallory S. Lambert, Joshua J. Horns, Sean Laverty, Laurie Dizney, Erik A. Beever, M. Denise Dearing
Improving conservation outcomes with a new paradigm for understanding species’ fundamental and realized adaptive capacity
Worldwide, many species are responding to ongoing climate change with shifts in distribution, abundance, phenology, or behavior. Consequently, natural-resource managers face increasingly urgent conservation questions related to biodiversity loss, expansion of invasive species, and deteriorating ecosystem services. We argue that our ability to address these questions is hampered by the lack of expl
Authors
Erik A. Beever, John O’Leary, Claudia Mengelt, Jordan M. West, Susan Julius, Nancy Green, Dawn Magness, Laura E. Petes, Bruce A. Stein, Adrienne B Nicotra, Jessica J Hellmann, Amanda L Robertson, Michelle D. Staudinger, Andrew A. Rosenberg, Eleanora Babij, Jean Brennan, Gregor W. Schuurman, Gretchen E Hofmann
The climate space of fire regimes in north-western North America
Aim. Studies of fire activity along environmental gradients have been undertaken, but the results of such studies have yet to be integrated with fire-regime analysis. We characterize fire-regime components along climate gradients and a gradient of human influence. Location. We focus on a climatically diverse region of north-western North America extending from northern British Columbia, Canada, to
Authors
Ellen Whitman, Enric Batllori, Marc-André Parisien, Carol Miller, Jonathan D. Coop, Meg A. Krawchuk, Geneva W. Chong, Sandra L. Haire
Managing more than the mean: Using quantile regression to identify factors related to large elk groups
Summary
Animal group size distributions are often right-skewed, whereby most groups are small, but most individuals occur in larger groups that may also disproportionately affect ecology and policy. In this case, examining covariates associated with upper quantiles of the group size distribution could facilitate better understanding and management of large animal groups.
We studied wintering elk
Authors
Angela K. Brennan, Paul C. Cross, Scott Creely