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Publications

Filter Total Items: 1990

Wintering ecology of adult North American ospreys

North American Ospreys (Pandion haliaetus) typically migrate long distances to their wintering grounds in the tropics. Beyond the general distribution of their wintering range (i.e., the Caribbean, South America, and Central America), very little is known about the wintering ecology of these birds. We used satellite telemetry to determine the duration of wintering period, to examine the characteri
Authors
Brian E. Washburn, Mark S. Martell, Richard O. Bierregaard, Charles J. Henny, Brian S. Dorr, Thomas J. Olexa

Mount Rainier National Park

Natural Resource Condition Assessments (NRCAs) evaluate current conditions for a subset of natural resources and resource indicators in national parks. NRCAs also report on trends in resource condition (when possible), identify critical data gaps, and characterize a general level of confidence for study findings. The resources and indicators emphasized in a given project depend on the park’s resou
Authors
Robert Hoffman, Andrea Woodward, Patricia K. Haggerty, Kurt J. Jenkins, Paul C. Griffin, M. J. Adams, Joan Hagar, Tonnie Cummings, Dan Duriscoe, Karen Kopper, Jon Riedel, Barbara Samora, Lelaina Marin, Guillaume S. Mauger, Karen Bumbaco, Jeremy S. Littell

Pedological and geological relationships with soil lichen and moss distribution in the eastern Mojave Desert, CA, USA

Biological soil crusts (biocrusts) are ubiquitous in drylands globally. Lichens and mosses are essential biocrust components and provide a variety of ecosystem services, making their conservation and management of interest. Accordingly, understanding what factors are correlated with their distribution is important to land managers. We hypothesized that cover would be related to geologic and pedolo
Authors
Jayne Belnap, David M. Miller, David R. Bedford, Susan L. Phillips

Interactions between a group of Golden Eagles and a herd of North American elk

Raptors are generally considered solitary predators (Schoener 1969), but occasionally they interact socially (Brown and Amadon 1968). Certain raptor species (e.g., Swallow-tailed Kites [Elanoides forficatus] and Swainson's Hawks [Buteo swainsoni]) concentrate in aggregations in response to localized, abundant food sources (Ellis et al. 1993). Many raptor species engage in group hunting (Ellis et a
Authors
Matt P. O'Connell, Michael N. Kochert

Outplanting Wyoming big sagebrush following wldfire: stock performance and economics

Finding ecologically and economically effective ways to establish matrix species is often critical for restoration success. Wyoming big sagebrush (Artemisia tridentata subsp. wyomingensis) historically dominated large areas of western North America, but has been extirpated from many areas by large wildfires; its re-establishment in these areas often requires active management. We evaluated the per
Authors
Eva Dettweiler-Robinson, Jonathan D. Bakker, James R. Evans, Heidi Newsome, G. Matt Davies, Troy A. Wirth, David A. Pyke, Richard T. Easterly, Debra Salstrom, Peter W. Dunwiddle

Raptor nesting near oil and gas development: an overview of key findings and implications for management based on four reports by HawkWatch International

The project was undertaken because of a paucity of information about the possible effects of OG operations and resource management on nesting raptors. BLM raptor management has included stipulations that restricted human activity near raptor nests during the raptor nesting season. The BLM and the Department of Energy (DOE), which provided financial support for the study, seek information th
Authors
Mark R. Fuller

Bird-vegetation associations in thinned and unthinned young Douglas-fir forests 10 years after thinning

Quantitative associations between animals and vegetation have long been used as a basis for conservation and management, as well as in formulating predictions about the influence of resource management and climate change on populations. A fundamental assumption embedded in the use of such correlations is that they remain relatively consistent over time. However, this assumption of stationarity has
Authors
Svetlana Yegorova, Matthew G. Betts, Joan Hagar, Klaus J. Puettmann

Nutrient limitation of native and invasive N2-fixing plants in northwest prairies

Nutrient rich conditions often promote plant invasions, yet additions of non-nitrogen (N) nutrients may provide a novel approach for conserving native symbiotic N-fixing plants in otherwise N-limited ecosystems. Lupinus oreganus is a threatened N-fixing plant endemic to prairies in western Oregon and southwest Washington (USA). We tested the effect of non-N fertilizers on the growth, reproduction,
Authors
Andrea S. Thorpe, Steven S. Perakis, Christina Catricala, Thomas N. Kaye

Forest calcium depletion and biotic retention along a soil nitrogen gradient

High nitrogen (N) accumulation in terrestrial ecosystems can shift patterns of nutrient limitation and deficiency beyond N toward other nutrients, most notably phosphorus (P) and base cations (calcium [Ca], magnesium [Mg], and potassium [K]). We examined how naturally high N accumulation from a legacy of symbiotic N fixation shaped P and base cation cycling across a gradient of nine temperate coni
Authors
Steven S. Perakis, Emily R. Sinkhorn, Christina Catricala, Thomas D. Bullen, John A. Fitzpatrick, Justin D. Hynicka, Kermit Cromack

Performance of quantitative vegetation sampling methods across gradients of cover in Great Basin plant communities

Resource managers and scientists need efficient, reliable methods for quantifying vegetation to conduct basic research, evaluate land management actions, and monitor trends in habitat conditions. We examined three methods for quantifying vegetation in 1-ha plots among different plant communities in the northern Great Basin: photography-based grid-point intercept (GPI), line-point intercept (LPI),
Authors
David S. Pilliod, Robert S. Arkle

Comparison of electrofishing techniques to detect larval lampreys in wadeable streams in the Pacific Northwest

We evaluated the probability of detecting larval lampreys using different methods of backpack electrofishing in wadeable streams in the U.S. Pacific Northwest. Our primary objective was to compare capture of lampreys using electrofishing with standard settings for salmon and trout to settings specifically adapted for capture of lampreys. Field work consisted of removal sampling by means of backpac
Authors
Jason B. Dunham, Nathan D. Chelgren, Michael P. Heck, Steven M. Clark

Spatial ecological processes and local factors predict the distribution and abundance of spawning by steelhead (Oncorhynchus mykiss) across a complex riverscape

Processes that influence habitat selection in landscapes involve the interaction of habitat composition and configuration and are particularly important for species with complex life cycles. We assessed the relative influence of landscape spatial processes and local habitat characteristics on patterns in the distribution and abundance of spawning steelhead (Oncorhynchus mykiss), a threatened salmo
Authors
Jeffrey A. Falke, Jason B. Dunham, Christopher E. Jordan, Kris M. McNyset, Gordon H. Reeves