Skip to main content
U.S. flag

An official website of the United States government

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

Snowpack signals in North American tree rings

Climate change has contributed to recent declines in mountain snowpack and earlier runoff, which in turn has intensified hydrological droughts in western North America. Climate model projections suggest that continued and severe snowpack reductions are expected over the 21st century, with profound consequences for ecosystems and human welfare. Yet the current understanding of trends and variabilit
Authors
Bethany L. Coulthard, Kevin J. Anchukaitis, Gregory T. Pederson, Edward R Cook, Jeremy Littell, Dan J. Smith

Upper Colorado River Basin 20th century droughts under 21st century warming: Plausible scenarios for the future

This study builds on a collaboration with a water resource management community of practice in the Upper Colorado River Basin to develop scenarios of future drought and assess impacts on water supply reliability. Water managers are concerned with the impacts of warming on water year streamflow, but uncertainties in projections of climate make the application of these projections to planning a chal
Authors
Connie A. Woodhouse, Rebecca M. Smith, Stephanie A. McAfee, Gregory T. Pederson, Gregory J. McCabe, W. Paul Miller, Adam Csank

High elevation ice patch documents Holocene climate variability in the northern Rocky Mountains

Paleoclimate records from ice cores generally are considered to be the most direct indicators of environmental change, but are rare from mid-latitude, continental regions such as the western United States. High-elevation ice patches are known to be important archaeological archives in alpine regions and potentially could provide records important for Earth System Model evaluation and to understand
Authors
Nathan J. Chellman, Gregory T. Pederson, Craig Lee, Dave McWethy, Kathryn Pusman, Jeffery R. Stone, Sabrina R. Brown, Joseph R. McConnell

The elephant in the lab (and field): Contamination in aquatic environmental DNA studies

The rapid evolution of environmental (e)DNA methods has resulted in knowledge gaps in smaller, yet critical details like proper use of negative controls to detect contamination. Detecting contamination is vital for confident use of eDNA results in decision-making. We conducted two literature reviews to summarize (a) the types of quality assurance measures taken to detect contamination of eDNA samp
Authors
Adam Sepulveda, Patrick R. Hutchins, Meghan Forstchen, Madeline Mckeefry, Anna M Swigris

Infectious diseases in Yellowstone’s wolves

No abstract available.
Authors
Ellen E. Brandell, Emily S. Almberg, Paul C. Cross, Andrew P Dobson, Douglas W. Smith, Peter J. Hudson

An evaluation of noninvasive sampling techniques for Malayan sun bears

Traditional mark–recapture studies to estimate abundance and trends of Malayan sun bear (Helarctos malayanus) populations are impeded by logistics of live-trapping wild individuals. The development of noninvasive sampling techniques for monitoring sun bear populations is therefore crucial for targeted conservation action. Sun bears have short fur, and conventional hair-snagging devices are ineffec
Authors
Thye Lim Tee, Wai Ling Lai, Terence Kok Ju Wei, Ooi Zhuan Shern, Frank T. van Manen, Stuart P. Sharp, Siew Te Wong, Jactty Chew, Shyamala Ratnayeke

Systematics, evolution, and genetics of bears

Molecular genetics are key to understanding current and historical relationships between isolated populations, including species’ colonizations during glacial–interglacial cycles, to determine viability of local populations, needs for habitat corridors, and other aspects of population management, especially where bears are harvested for sport, etc. As natural habitats shrink, some bear species wil
Authors
Andrew C Kitchener, Eva Bellemain, Xiang Ding, Alexander Kopatz, Verena Kutschera, Valentina Salomashkina, Manuel Ruiz-Garcia, Tabitha Graves, Yiling Hou, Lars Werdelin, Axel Janke

Post-fire vegetation response in a repeatedly burned low-elevation sagebrush steppe protected area provides insights about resilience and invasion resistance

Sagebrush steppe ecosystems are threatened by human land-use legacies, biological invasions, and altered fire and climate dynamics. Steppe protected areas are therefore of heightened conservation importance but are few and vulnerable to the same impacts broadly affecting sagebrush steppe. To address this problem, sagebrush steppe conservation science is increasingly emphasizing a focus on resilien
Authors
Tom Rodhouse, Kathryn M. Irvine, Lisa Bowersock

Influence of water temperature and biotic interactions on the distribution of westslope cutthroat trout (Oncorhynchus clarkii lewisi) in a population stronghold under climate change

Climate warming is expected to have substantial impacts on native trout across the Rocky Mountains, but there is little understanding of how these changes affect future distributions of co-occurring native fishes within population strongholds. We used mixed-effects logistic regression to investigate the role of abiotic (e.g., temperature) and biotic factors (bull trout presence, Salvelinus conflue
Authors
Kadie Heinle, Lisa A Eby, Clint C. Muhlfeld, Amber Steed, Leslie Jones, Vincent S. D'Angelo, Andrew R. Whiteley, Mark Hubblewhite

Evaluating wildlife translocations using genomics: A bighorn sheep case study

Wildlife restoration often involves translocation efforts to reintroduce species and supplement small, fragmented populations. We examined the genomic consequences of bighorn sheep (Ovis canadensis) translocations and population isolation to enhance understanding of evolutionary processes that affect population genetics and inform future restoration strategies. We conducted a population genomic an
Authors
Elizabeth P Flesch, Tabitha Graves, Jennifer Thomson, Kelly Proffitt, P.J. White, Thomas R Stephenson, Robert A. Garrott

It’s complicated…environmental DNA as a predictor of trout and char abundance in streams

The potential to provide inferences about fish abundance from environmental (e)DNA samples has generated great interest. However, the accuracy of these abundance estimates is often low and variable across species and space. A plausible refinement is the use of common aquatic habitat monitoring data to account for attributes that influence eDNA dynamics. We therefore evaluated the relationships bet
Authors
Adam Sepulveda, Robert Al-Chokhachy, Matthew Laramie, Kyle Crapster, Ladd Knotek, Brian T. Miller, Alexander V. Zale, David Pilliod

Hybridization alters growth and migratory life-history expression of native trout

Human-mediated hybridization threatens many native species, but the effects of introgressive hybridization on life-history expression are rarely quantified, especially in vertebrates. We quantified the effects of non-native rainbow trout admixture on important life-history traits including growth and partial migration behavior in three populations of westslope cutthroat trout over five years. Rain
Authors
Jeffrey Strait, Lisa A Eby, Ryan P. Kovach, Clint C. Muhlfeld, Matthew Boyer, Stephen J. Amish, Seth Smith, Winsor H. Lowe, Gordon Luikart