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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: 1197

Rub tree use and selection by American black bears and grizzly bears in northern Yellowstone National Park

Several of the world's bear species exhibit tree-rubbing behavior, which is thought to be a form of scent-marking communication. Many aspects of this behavior remain unexplored, including differences in rub tree selection between sympatric bear species. We compiled rub tree data collected on Yellowstone National Park's Northern Range (USA) and compared rub tree selection of sympatric American blac
Authors
Nathaniel R. Bowersock, H. Okada, Andrea R. Litt, Kerry A. Gunther, Frank T. van Manen

Streamflow reconstructions from tree rings and variability in drought and surface water supply for the Milk and St. Mary River basins

The Milk and St. Mary Rivers are international waterways straddling the United States and Canada and traversing four Tribal Nations before draining into the Missouri and South Saskatchewan Rivers respectively. Management of water resources in the region is challenged by the complexity of stakeholder interests, the limitations of existing management infrastructure, and by a limited characterization
Authors
Justin Martin, Gregory T. Pederson

Using structured decision making to evaluate potential management responses to detection of dreissenid mussel (Dreissena spp.) environmental DNA

Environmental (e)DNA tools are sensitive and cost-effective for early detection of invasive species. However, the uncertainty associated with the interpretation of positive eDNA detections makes it challenging to determine appropriate natural resource management responses. Multiple sources of error can give rise to positive detections of eDNA in a sample when individuals of that species are not pr
Authors
Adam J. Sepulveda, David R. Smith, Katherine M O'Donnell, Nathan Owens, Brittany White, Catherine A. Richter, Christopher M. Merkes, Skylar Wolf, Mike Rau, Matthew Neilson, Wesley Daniel, Christine E. Dumoulin, Margaret Hunter

Stream size, temperature, and density explain body sizes of freshwater salmonids across a range of climate conditions

Climate change and anthropogenic activities are altering the body sizes of fishes, yet our understanding of factors influencing body size for many taxa remains incomplete. We evaluated the relationships between climate, environmental, and landscape attributes and the body size of different taxa of freshwater trout (Salmonidae) in the USA. Hierarchical spatial modeling across a gradient of habitats
Authors
Robert K. Al-Chokhachy, Benjamin Letcher, Clint C. Muhlfeld, Jason B. Dunham, Timothy Joseph Cline, Nathaniel P. Hitt, James Roberts, David Schmetterling

Status and trends of North American bats: Summer occupancy analysis 2010-2019

• We developed an analytical pipeline supported by web-based infrastructure for integrating continental scale bat monitoring data (stationary acoustic, mobile acoustic, and capture records) to estimate summer (May 1–Aug 31) occupancy probabilities and changes in occupancy over time for 12 North American bat species. This serves as one of multiple lines of evidence that inform the status and trends

Authors
Bradley James Udell, Bethany Straw, Tina L. Cheng, Kyle Enns, Winifred F. Frick, Benjamin Gotthold, Kathryn Irvine, Cori Lausen, Susan Loeb, Jonathan D. Reichard, Thomas J. Rodhouse, Dane Smith, Christian Stratton, Wayne E. Thogmartin, Brian Reichert

A framework to integrate innovations in invasion science for proactive management

Invasive alien species (IAS) are a rising threat to biodiversity, national security, and regional economies, with impacts in the hundreds of billions of U.S. dollars annually. Proactive or predictive approaches guided by scientific knowledge are essential to keeping pace with growing impacts of invasions under climate change. Although the rapid development of diverse technologies and approaches ha
Authors
Charles B. van Rees, Brian K. Hand, Sean C. Carter, Charles Bargeron, Timothy Joseph Cline, Wesley Daniel, Jason A. Ferrante, Keith Gaddis, Margaret E. Hunter, Catherine S. Jarnevich, Melodie A. McGeoch, Jeffrey T. Morisette, Matthew E. Neilson, Helen E. Roy, Mary Ann Rozance, Adam J. Sepulveda, Rebekah D. Wallace, Diane Whited, Taylor Wilcox, John S. Kimball, Gordon Luikart

Climate and landscape controls on old-growth western juniper demography in the northern Great Basin, USA

Western juniper (Juniperus occidentalis Hook.) woodlands have persisted for millennia in semiarid parts of the northern Great Basin, USA, providing critical habitat for plant and animal species. Historical records suggest that the establishment of western juniper is strongly associated with regional climatic variability. For example, the abundance of western juniper pollen and macrofossils measure
Authors
Rachel A. Loehman, Emily K. Heyerdahl, Gregory T. Pederson, David B. McWethy

Water availability drives instream conditions and life-history of an imperiled desert fish: A case study to inform water management

In arid ecosystems, available water is a critical, yet limited resource for human consumption, agricultural use, and ecosystem processes—highlighting the importance of developing management strategies to meet the needs of multiple users. Here, we evaluated how water availability influences stream thermal regimes and life-history expressions of Lahontan cutthroat trout (Oncorhynchus clarkii henshaw
Authors
Robert K. Al-Chokhachy, Roger Peka, Erik Horgen, Daniel J. Kaus, Tim Loux, Lisa Heki

Using physiological conditions to assess current and future habitat use of a Subarctic frog

Species with especially close dependence on the environment to meet physiological requirements, such as ectotherms, are highly susceptible to the impacts of climate change. Climate change is occurring rapidly in the Subarctic and Arctic, but there is limited knowledge on ectotherm physiology in these landscapes. We investigated how environmental conditions and habitat characteristics influence the
Authors
T. Hastings, Blake R. Hossack, L. Fishback, J. M. Davenport

Importance of local weather and environmental gradients on demography of a broadly distributed temperate frog

Amphibian populations are sensitive to environmental temperatures and moisture, which vary with local weather conditions and may reach new norms and extremes as contemporary climate change progresses. Using long-term (11–16 years) mark-recapture data from 10 populations of the Columbia spotted frog (Rana luteiventris) from across its U.S. range, we addressed hypotheses about how demographic relati
Authors
David Pilliod, Rebecca McCaffery, Robert Arkle, Rick D. Scherer, Jacqueline B. Cupples, Lisa A. Eby, Blake R. Hossack, Hallie Lingo, Kristin N. Lohr, Bryce A. Maxell, Megan J. McGuire, Chad Mellison, Marisa K. Meyer, James C. Munger, Teri Slatauski, Rachel Van Horne

Precision and bias of spatial capture–recapture estimates: A multi-site, multi-year Utah black bear case study

Spatial capture–recapture (SCR) models are powerful analytical tools that have become the standard for estimating abundance and density of wild animal populations. When sampling populations to implement SCR, the number of unique individuals detected, total recaptures, and unique spatial relocations can be highly variable. These sample sizes influence the precision and accuracy of model parameter e
Authors
Greta M Schmidt, Tabitha Graves, Jordan C Pederson, Sarah L Carroll