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Publications

Filter Total Items: 1990

Response of aboveground carbon balance to long-term, experimental enhancements in precipitation seasonality is contingent on plant community type in cold-desert rangelands

Semi-arid rangelands are important carbon (C) pools at global scales. However, the degree of net C storage or release in water-limited systems is a function of precipitation amount and timing, as well as plant community composition. In northern latitudes of western North America, C storage in cold-desert ecosystems could increase with boosts in wintertime precipitation, in which climate models pre
Authors
Kathryn McAbee, Keith Reinhardt, Matthew J. Germino, Andrew Bosworth

Range-wide connectivity of priority areas for Greater Sage-Grouse: Implications for long-term conservation from graph theory

The delineation of priority areas in western North America for managing Greater Sage-Grouse (Centrocercus urophasianus) represents a broad-scale experiment in conservation biology. The strategy of limiting spatial disturbance and focusing conservation actions within delineated areas may benefit the greatest proportion of Greater Sage-Grouse. However, land use under normal restrictions outside prio
Authors
Michele R. Crist, Steven T. Knick, Steven E. Hanser

Riparian soil development linked to forest succession above and below dams along the Elwha River, Washington, USA

Riparian forest soils can be highly dynamic, due to frequent fluvial disturbance, erosion, and sediment deposition, but effects of dams on riparian soils are poorly understood. We examined soils along toposequences within three river segments located upstream, between, and downstream of two dams on the Elwha River to evaluate relationships between riparian soil development and forest age, successi
Authors
Laura G Perry, Patrick B. Shafroth, Steven Perakis

Mercury bioaccumulation in estuarine fishes: Novel insights from sulfur stable isotopes

Estuaries are transitional habitats characterized by complex biogeochemical and ecological gradients that result in substantial variation in fish total mercury concentrations (THg). We leveraged these gradients and used carbon (δ13C), nitrogen (δ15N), and sulfur (δ34S) stable isotopes to examine the ecological and biogeochemical processes underlying THg bioaccumulation in fishes from the San Franc
Authors
James J. Willacker, Collin A. Eagles-Smith, Joshua T. Ackerman

Spatial demographic models to inform conservation planning of golden eagles in renewable energy landscapes

Spatial demographic models can help guide monitoring and management activities targeting at-risk species, even in cases where baseline data are lacking. Here, we provide an example of how site-specific changes in land use and anthropogenic stressors can be incorporated into a spatial demographic model to investigate effects on population dynamics of Golden Eagles (Aquila chrysaetos). Our study foc
Authors
J. David Wiens, Nathan H. Schumaker, Richard D. Inman, Todd C. Esque, Kathleen M. Longshore, Kenneth E. Nussear

Warming and provenance limit tree recruitment across and beyond the elevation range of subalpine forest

Climate niche models project that subalpine forest ranges will extend upslope with climate warming. These projections assume that the climate suitable for adult trees will be adequate for forest regeneration, ignoring climate requirements for seedling recruitment, a potential demographic bottleneck. Moreover, local genetic adaptation is expected to facilitate range expansion, with tree populations
Authors
Lara M. Kueppers, Erin Conlisk, Cristina Castanha, Andrew B. Moyes, Matthew J. Germino, Perry de Valpine, Margaret S. Torn, Jeffry B. Mitton

Ground squirrel shooting and potential lead exposure in breeding avian scavengers

Recreational ground squirrel shooting is a popular activity throughout the western United States and serves as a tool for managing ground squirrel populations in agricultural regions. Belding’s ground squirrels (Spermophilus beldingi) are routinely shot in California, Nevada, and Oregon across habitats that overlap with breeding avian scavengers. Ground squirrels shot with lead (Pb)-based bullets
Authors
Garth Herring, Collin A. Eagles-Smith, Mason T. Wagner

Potential trophic cascades triggered by the barred owl range expansion

Recently, the barred owl (Strix varia) has expanded its range into the Pacific Northwest of the United States resulting in pronounced effects on the demography and behavior of the northern spotted owl (S. occidentalis caurina). The range expansion has brought together historically allopatric species, creating the potential for significant changes in the avian predator community with possible casca
Authors
Samantha R. Holm, Barry R. Noon, David Wiens, William J. Ripple

Use of noninvasive genetics to assess nest and space use by white-tailed eagles

Movement and space use are important components of animal interactions with the environment. However, for hard-to-monitor raptor species, there are substantial gaps in our understanding of these key determinants. We used noninvasive genetic tools to evaluate the details of space use over a 3-yr period by White-tailed Eagles (Haliaeetus albicilla) at the Naurzum Zapovednik in northern Kazakhstan. W
Authors
Zafer Bulut, Evgeny A. Bragin, J. Andrew DeWoody, Melissa A. Braham, Todd E. Katzner, Jacqueline M. Doyle

Interagency Pacific marten (Martes caurina) distribution study on the Olympic Peninsula, Washington

The objective of this study was to determine if the Pacific marten (Martes caurina) still occurs on the Olympic Peninsula in Washington State. We reviewed recent records of marten observations on the Olympic Peninsula since 1998, and conducted new surveys in undersampled regions of the Olympic Peninsula during summer, 2016. We reviewed evidence of fisher presence from 6 previously reported stud
Authors
Katie Moriarty, Betsy Howell, Connor Morozumi, Patti Happe, Kurt J. Jenkins, Keith B. Aubry

Using resilience and resistance concepts to manage threats to sagebrush ecosystems, Gunnison sage-grouse, and Greater sage-grouse in their eastern range: A strategic multi-scale approach

This report provides a strategic approach developed by a Western Association of Fish and Wildlife Agencies interagency working group for conservation of sagebrush ecosystems, Greater sage-grouse, and Gunnison sage-grouse. It uses information on (1) factors that influence sagebrush ecosystem resilience to disturbance and resistance to nonnative invasive annual grasses and (2) distribution and relat
Authors
Jeanne C. Chambers, Jeffrey L. Beck, Steve Campbell, John Carlson, Thomas J. Christiansen, Karen J. Clause, Jonathan B. Dinkins, Kevin E. Doherty, Kathleen A. Griffin, Douglas W. Havlina, Kenneth F. Mayer, Jacob D. Hennig, Laurie L. Kurth, Jeremy D. Maestas, Mary E. Manning, Brian A. Mealor, Clinton McCarthy, Marco A. Perea, David A. Pyke

Unusual clockwise loop migration lengthens travel distances and increases potential risks for a central Asian, long distance, trans-equatorial migrant, the Red-footed Falcon Falco vespertinus

Capsule: Red-footed Falcons Falco vespertinus migrating from northern Kazakhstan proceed west before heading south to Africa; their northbound travel follows a different route with passage close to shooting hotspots in the Mediterranean.Aim: To use tracking and ringing data to document for the first time the migration of globally threatened Red-footed Falcons from northern Kazakhstan.Methods: Ligh
Authors
Todd E. Katzner, Evgeny A. Bragin, Alexander E. Bragin, Michael J. McGrady, Tricia A. Miller, Keith L. Bildstein