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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: 1211

Size‐assortative choice and mate availability influences hybridization between red wolves (Canis rufus) and coyotes (Canis latrans)

Anthropogenic hybridization of historically isolated taxa has become a primary conservation challenge for many imperiled species. Indeed, hybridization between red wolves (Canis rufus) and coyotes (Canis latrans) poses a significant challenge to red wolf recovery. We considered seven hypotheses to assess factors influencing hybridization between red wolves and coyotes via pair‐bonding between the
Authors
Joseph W. Hinton, John L. Gittleman, Frank T. van Manen, Michael J. Chamberlain

Spatiotemporal heterogeneity in prey abundance and vulnerability shapes the foraging tactics of an omnivore

Prey abundance and prey vulnerability vary across space and time, but we know little about how they mediate predator–prey interactions and predator foraging tactics. To evaluate the interplay between prey abundance, prey vulnerability and predator space use, we examined patterns of black bear (Ursus americanus) predation of caribou (Rangifer tarandus) neonates in Newfoundland, Canada using data fr
Authors
Nathaniel D. Rayl, Guillaume Bastille-Rousseau, John F. Organ, Matthew Mumma, Shane P. Mahoney, Colleen Soulliere, Keith Lewis, Robert Otto, Dennis Murray, Lisette Waits, Todd Fuller

Long-term population dynamics and conservation risk of migratory bull trout in the upper Columbia River basin

We used redd count data from 88 bull trout (Salvelinus confluentus) populations in the upper Columbia River basin to quantify local and regional patterns in population dynamics, including adult abundance, long-term trend, and population synchrony. We further used this information to assess conservation risk of metapopulations using eight population dynamic metrics associated with persistence. Loca
Authors
Ryan Kovach, Jonathan Armstrong, David Schmetterling, Robert Al-Chokhachy, Clint C. Muhlfeld

Migratory hummingbirds make their own rules: The decision to resume migration along a barrier

Knowing how naïve migrants respond to intrinsic and extrinsic factors experienced en route will allow a more thorough understanding of the endogenous migratory programme. To understand how inexperienced individuals respond to ecological features, we tracked the migratory departures of juvenile ruby-throated hummingbirds, Archilochus colubris, one of the smallest (∼ 3 g) and least-studied migrants,
Authors
Theodore J. Zenzal, Frank R. Moore, Robert H. Diehl, Michael B. Ward, JIll Deppe

Winter feeding of elk in the Greater Yellowstone Ecosystem and its effects on disease dynamics

Providing food to wildlife during periods when natural food is limited results in aggregations that may facilitate disease transmission. This is exemplified in western Wyoming where institutional feeding over the past century has aimed to mitigate wildlife–livestock conflict and minimize winter mortality of elk (Cervus canadensis). Here we review research across 23 winter feedgrounds where the mos
Authors
Gavin G. Cotterill, Paul C. Cross, Eric Cole, Rebecca K. Fuda, Jared D. Rogerson, Brandon Scurlock, Johan T. du Toit

Fish response to contemporary timber harvest practices in a second-growth forest from the central Coast Range of Oregon

We used a paired-watershed approach to investigate the effects of contemporary logging practices on headwater populations of coastal cutthroat trout (Oncorhynchus clarkii clarkii) and juvenile coho salmon (Oncorhynchus kisutch) in a second-growth Douglas-fir forested catchment in Oregon. Stream habitat and fish population characteristics, including biomass, abundance, growth, size, and movement, w
Authors
Douglas S. Bateman, Robert E. Gresswell, Dana Warren, David Hockman-Wert, David W. Leer, Jeffrey T. Light, John D. Stednick

Oil and gas development footprint in the Piceance Basin, western Colorado

Understanding long-term implications of energy development on ecosystem functionrequires establishing regional datasets to quantify past development and determine relationships to predict future development. The Piceance Basin in western Colorado has a history of energy production and development is expected to continue into the foreseeable future due to abundant natural gas resources. To facilita
Authors
Cericia D. Martinez, Todd M. Preston

On the exchange of sensible and latent heat between the atmosphere and melting snow

The snow energy balance is difficult to measure during the snowmelt period, yet critical for predictions of water yield in regions characterized by snow cover. Robust simplifications of the snowmelt energy balance can aid our understanding of water resources in a changing climate. Research to date has demonstrated that the net turbulent flux (FT) between a melting snowpack and the atmosphere is ne
Authors
Paul C. Stoy, Erich H. Peitzsch, David J. A. Wood, Daniel Rottinghaus, Georg Wohlfahrt, Michael Goulden, Helen Ward

Annotated bibliography of scientific research on greater sage-grouse published since January 2015

The greater sage-grouse (Centrocercus urophasianus; hereafter GRSG) has been a focus of scientific investigation and management action for the past two decades. The 2015 U.S. Fish and Wildlife Service listing determination of “not warranted” was in part due to a large-scale collaborative effort to develop strategies to conserve GRSG populations and their habitat and to reduce threats to both. New
Authors
Sarah K. Carter, Daniel J. Manier, Robert S. Arkle, Aaron N. Johnston, Susan L. Phillips, Steven E. Hanser, Zachary H. Bowen

Occurrence of quiescence in free-ranging migratory songbirds

Quiescence is a period of inactivity that occurs before the onset of migratory activity in nocturnally migrating birds. This behavior has been observed in captive birds in migratory disposition, but its occurrence in free-ranging migratory birds has been documented only anecdotally, and causal factors and function(s), if any, are unknown. In this study, we documented and characterized quiescence i
Authors
Lynn N. Schofield, Jill L. Deppe, Robert H. Diehl, Michael P. Ward, Rachel T. Bolus, Theodore J. Zenzal, Jaclyn A. Smolinsky, Frank R. Moore

Vegetation responses to sagebrush-reduction treatments measured by satellites

Time series of vegetative indices derived from satellite imagery constitute tools to measure ecological effects of natural and management-induced disturbances to ecosystems. Over the past century, sagebrush-reduction treatments have been applied widely throughout western North America to increase herbaceous vegetation for livestock and wildlife. We used indices from satellite imagery to 1) quantif
Authors
Aaron N. Johnston, Erik A. Beever, Jerod Merkle, Geneva W. Chong

Demographic modelling reveals a history of divergence with gene flow for a glacially tied stonefly in a changing post-Pleistocene landscape

AimClimate warming is causing extensive loss of glaciers in mountainous regions, yet our understanding of how glacial recession influences evolutionary processes and genetic diversity is limited. Linking genetic structure with the influences shaping it can improve understanding of how species respond to environmental change. Here, we used genome-scale data and demographic modelling to resolve the
Authors
Scott Hotaling, Clint C. Muhlfeld, J. Joseph Giersch, Omar Ali, Steve Jordan, Michael R. Miller, Gordon Luikart, David W. Weisrock