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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

Development of new information to inform fish passage decisions at the Yale and Merwin hydro projects on the Lewis River, Washington—Final report, 2018

The reintroduction of extirpated salmonids to historically occupied areas is becoming increasingly common as a conservation and recovery strategy. Often, reintroductions are implemented after the factors that originally led to species extirpation have been reduced, eliminated, or mitigated. For anadromous Oncorhynchus spp. (Pacific salmon) and O. mykiss (steelhead), addressing barriers to migratio
Authors
Robert K. Al-Chokhachy, Christopher L. Clark, Mark H. Sorel, David A. Beauchamp

Impacts of nonnative Brown Trout on Yellowstone Cutthroat Trout in a tributary stream

Nonnative trout are a considerable threat to native salmonids, yet our understanding of the mechanisms behind interspecific interactions remains limited. We evaluated the impacts of nonnative Brown Trout Salmo salar on a population of Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri in Montana. We contrasted diets, growth, and survival of Yellowstone Cutthroat Trout occurring in allopatry
Authors
Robert K. Al-Chokhachy, Adam J. Sepulveda

No flood effect on recruitment of a small Louisiana black bear population

A flood event in 2011 had minor impacts on apparent survival and movement probabilities of a small, isolated population of Louisiana black bears (Ursus americanus luteolus) in the Upper Atchafalaya River Basin, Louisiana, USA. However, the potential effects of the flood on recruitment of juveniles into the population, then listed as threatened under the United States Endangered Species Act, were n
Authors
Joseph D. Clark, Kaitlin C. O'Connell-Goode, Carrie L. Lowe, Sean M. Murphy, Sutton C. Maehr, Maria M. Davidson, Jared S. Laufenberg

Extreme value-based methods for modeling elk yearly movements

Species range shifts and the spread of diseases are both likely to be driven by extreme movements, but are difficult to statistically model due to their rarity. We propose a statistical approach for characterizing movement kernels that incorporate landscape covariates as well as the potential for heavy-tailed distributions. We used a spliced distribution for distance travelled paired with a resour
Authors
Dhanushi A. Wijeyakulasuriya, Ephraim M. Hanks, Benjamin A. Shaby, Paul C. Cross

Keeping the crown of the continent connected: An interagency US2 connectivity workshop report

At over 2.5 million acres, Glacier National Park and the Bob Marshall Wilderness complex form one of the largest protected areas in the continental United States. Straddling the Continental Divide, these two areas form a vital linkage between vast areas of public land to the south towards Yellowstone, and contiguous protected areas north of the US-Canada border. However, US Highway 2 (US2) and the
Authors
John S. Waller, Tabitha Graves

Change in dominance determines herbivore effects on plant biodiversity

Herbivores alter plant biodiversity (species richness) in many of the world’s ecosystems, but the magnitude and the direction of herbivore effects on biodiversity vary widely within and among ecosystems. One current theory predicts that herbivores enhance plant biodiversity at high productivity but have the opposite effect at low productivity. Yet, empirical support for the importance of site prod
Authors
Sally E. Koerner, Melinda D. Smith, Deron E. Burkepile, Niall P. Hanan, Meghan L. Avolio, Scott L. Collins, Alan K. Knapp, Nathan P. Lemoine, Elisabeth J. Forrestel, Stephanie Eby, Dave I. Thompson, Gerardo A. Aguado-Santacruz, John P. Anderson, T. Michael Anderson, Ayana Angassa, Sumanta Bagchi, Elisabeth S. Bakker, Gary Bastin, Lauren E. Baur, Karen H. Beard, Erik A. Beever, Patrick J. Bohlen, Elizabeth H. Boughton, Don Canestro, Ariela Cesa, Enrique Chaneton, Jimin Cheng, Carla M. D'Antonio, Claire Deleglise, Fadiala Dembélé, Josh Dorrough, David J. Eldridge, Barbara Fernandez-Going, Silvia Fernández-Lugo, Lauchlan H. Fraser, Bill Freedman, Gonzalo García-Salgado, Jacob R. Goheen, Liang Guo, Sean Husheer, Moussa Karembé, Johannes M. H. Knops, Tineke Kraaij, Andrew Kulmatiski, Minna-Maarit Kytöviita, Felipe Lezama, Gregory Loucougaray, Alejandro Loydi, Daniel G. Milchunas, Suzanne J. Milton, John W. Morgan, Claire Moxham, Kyle C. Nehring, Han Olff, Todd M. Palmer, Salvador Rebollo, Corinna Riginos, Anita C. Risch, Marta Rueda, Mahesh Sankaran, Takehiro Sasaki, Kathryn A. Schoenecker, Nick L. Schultz, Martin Schütz, Angelika Schwabe, Frances Siebert, Christian Smit, Karen A. Stahlheber, Christian Storm, Dustin J. Strong, Jishuai Su, Yadugiri V. Tiruvaimozhi, Claudia Tyler, James Val, Martijn L. Vandegehuchte, Kari E. Veblen, Lance Vermeire, David Ward, Jianshuang Wu, Truman P. Young, Qiang Yu, Tamara J. Zelikova

Estimating the risk of elk-to-livestock brucellosis transmission in Montana

Wildlife reservoirs of infectious disease are a major source of human-wildlife conflict because of the risk of potential spillover associated with commingling of wildlife and livestock. In Montana, the presence of brucellosis (Brucella abortus) in free-ranging elk (Cervus canadensis) populations is of significant management concern because of the risk of disease transmission from elk to livestock.
Authors
Nathaniel D. Rayl, Kelly Proffitt, Emily S. Almberg, Jennifer D. Jones, Jerod Merkle, Justin A. Gude, Paul C. Cross

Hidden cost of disease in a free‐ranging ungulate: brucellosis reduces mid‐winter pregnancy in elk

Demonstrating disease impacts on the vital rates of free‐ranging mammalian hosts typically requires intensive, long‐term study. Evidence for chronic pathogens affecting reproduction but not survival is rare, but has the potential for wide‐ranging effects. Accurately quantifying disease‐associated reductions in fecundity is important for advancing theory, generating accurate predictive models, and
Authors
Gavin G. Cotterill, Paul C. Cross, Arthur D. Middleton, Jared D. Rogerson, Brandon Scurlock, Johan T. Du Toit

Effects of climate-related stream factors on patterns of individual summer growth of Cutthroat Trout

Coldwater fishes are sensitive to abiotic and biotic stream factors, which can be influenced by climate. Distributions of inland salmonids in North America have declined significantly, with many of the current strongholds located in small headwater systems that may serve as important refugia as climate change progresses. We investigated the effects of discharge, stream temperature, trout biomass,
Authors
Patrick Uthe, Robert K. Al-Chokhachy, Bradley Shepard, Alexander V. Zale, Jeffrey L. Kershner

Estimating apparent survival of songbirds crossing the Gulf of Mexico during autumn migration

Many migratory bird species are declining, and the migratory period may limit populations because of the risk in traversing large geographical features during passage. Using automated radio-telemetry, we tracked 139 Swainson's thrushes (Catharus ustulatus) departing coastal Alabama, USA and crossing the Gulf of Mexico to arrive in the Yucatan Peninsula, Mexico during autumn. We estimated apparent
Authors
Michael P. Ward, Thomas J. Benson, JIll Deppe, Theodore J. Zenzal, Robert H. Diehl, Antonio Celis-Murillo, Rachel T Bolus, Frank R. Moore

Forecasting for dry and wet avalanches during mixed rain and snow storm events

Natural wet slab avalanches release when rain or melt water decreases snowpack strength, and natural dry slab avalanches release when an increased load overcomes snowpack strength. This study investigates avalanche activity resulting from mixed rain and snow falling on a faceted snowpack. This scenario produced an extensive slab avalanche cycle in March 2018 in the mountains near Ketchum, Idaho, w
Authors
Scott Savage, Erich Peitzsch, Simon Trautman, Benjamin VandenBos

Detecting snow depth change in avalanche path starting zones using uninhabited aerial systems and structure from motion photogrammetry

Understanding snow depth distribution and change is useful for avalanche forecasting and mitigation, runoff forecasting, and infrastructure planning. Advances in remote sensing are improving the ability to collect snow depth measurements. The development of structure from motion (SfM), a photogrammetry technique, combined with the use of uninhabited aerial systems (UASs) allows for high resolution
Authors
Erich H. Peitzsch, Daniel B. Fagre, Jordy Hendrikx, Karl W. Birkeland