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Publications

Filter Total Items: 1999

Sampling animal sign in heterogeneous environments: how much is enough?

Animal ecologists often use animal sign as a surrogate for direct observation of organisms, especially when species are secretive or difficult to observe. Spatial heterogeneity in arid environments makes it challenging to consistently detect and precisely characterize animal sign, which can bias estimates of animal abundance or habitat use. Piute ground squirrels (Urocitellus mollis) and Owyhee ha
Authors
Joseph D. Holbrook, Robert S. Arkle, Janet L. Rachlow, Kerri T. Vierling, David S. Pilliod

Estimation of occupancy, breeding success, and predicted abundance of golden eagles (Aquila chrysaetos) in the Diablo Range, California, 2014

We used a multistate occupancy sampling design to estimate occupancy, breeding success, and abundance of territorial pairs of golden eagles (Aquila chrysaetos) in the Diablo Range, California, in 2014. This method uses the spatial pattern of detections and non-detections over repeated visits to survey sites to estimate probabilities of occupancy and successful reproduction while accounting for imp
Authors
J. David Wiens, Patrick S. Kolar, Mark R. Fuller, W. Grainger Hunt, Teresa Hunt

Higher-order statistical moments and a procedure that detects potentially anomalous years as two alternative methods describing alterations in continuous environmental data

Statistics of central tendency and dispersion may not capture relevant or desired characteristics of the distribution of continuous phenomena and, thus, they may not adequately describe temporal patterns of change. Here, we present two methodological approaches that can help to identify temporal changes in environmental regimes. First, we use higher-order statistical moments (skewness and kurtosis
Authors
Ivan Arismendi, Sherri L. Johnson, Jason B. Dunham

Mitigation effectiveness for improving nesting success of greater sage-grouse influenced by energy development

Sagebrush Artemisia spp. habitats being developed for oil and gas reserves are inhabited by sagebrush obligate species — including the greater sage-grouse Centrocercus urophasianus (sage-grouse) that is currently being considered for protection under the U.S. Endangered Species Act. Numerous studies suggest increasing oil and gas development may exacerbate species extinction risks. Therefore, ther
Authors
Christopher P. Kirol, Andrew L. Sutphin, Laura S. Bond, Mark R. Fuller, Thomas L. Maechtle

Convergence of soil nitrogen isotopes across global climate gradients

Quantifying global patterns of terrestrial nitrogen (N) cycling is central to predicting future patterns of primary productivity, carbon sequestration, nutrient fluxes to aquatic systems, and climate forcing. With limited direct measures of soil N cycling at the global scale, syntheses of the 15 N: 14 N ratio of soil organic matter across climate gradients provide key insights into understanding g
Authors
Joseph M. Craine, Andrew J. Elmore, Lixin Wang, Laurent Augusto, W. Troy Baisden, E. N. J. Brookshire, Michael D. Cramer, Niles J. Hasselquist, Erik A. Hobbie, Ansgar Kahmen, Keisuke Koba, J. Marty Kranabetter, Michelle C. Mack, Erika Marin-Spiotta, Jordan R. Mayor, Kendra K. McLauchlan, Anders Michelsen, Gabriela B. Nardoto, Rafael S. Oliveira, Steven S. Perakis, Pablo L. Peri, Carlos A. Quesada, Andreas Richter, Louis A. Schipper, Bryan A. Stevenson, Benjamin L. Turner, Ricardo A. G. Viani, Wolfgang Wanek, Bernd Zeller

Long-term plant responses to climate are moderated by biophysical attributes in a North American desert

Recent elevated temperatures and prolonged droughts in many already water-limited regions throughout the world, including the southwestern U.S., are likely to intensify according to future climate-model projections. This warming and drying can negatively affect perennial vegetation and lead to the degradation of ecosystem properties. To better understand these detrimental effects, we formulate a
Authors
Seth M. Munson, Robert H. Webb, David C. Housman, Kari E. Veblen, Kenneth E. Nussear, Erik A. Beever, Kristine B. Hartney, Maria N. Miriti, Susan L. Phillips, Robert E. Fulton, Nita G. Tallent

Fire modulates climate change response of simulated aspen distribution across topoclimatic gradients in a semi-arid montane landscape

Content Changing aspen distribution in response to climate change and fire is a major focus of biodiversity conservation, yet little is known about the potential response of aspen to these two driving forces along topoclimatic gradients. Objective This study is set to evaluate how aspen distribution might shift in response to different climate-fire scenarios in a semi-arid montane landscape, and q
Authors
Jian Yang, Peter J. Weisberg, Douglas J. Shinneman, Thomas E. Dilts, Susan L. Earnst, Robert M Scheller

Characterizing the distribution of an endangered salmonid using environmental DNA analysis

Determining species distributions accurately is crucial to developing conservation and management strategies for imperiled species, but a challenging task for small populations. We evaluated the efficacy of environmental DNA (eDNA) analysis for improving detection and thus potentially refining the known distribution of Chinook salmon (Oncorhynchus tshawytscha) in the Methow and Okanogan Subbasins
Authors
Matthew B. Laramie, David S. Pilliod, Caren S. Goldberg

Intercontinental genetic structure and gene flow in Dunlin (Calidris alpina), a potential vector of avian influenza

Waterfowl (Anseriformes) and shorebirds (Charadriiformes) are the most common wild vectors of influenza A viruses. Due to their migratory behavior, some may transmit disease over long distances. Migratory connectivity studies can link breeding and nonbreeding grounds while illustrating potential interactions among populations that may spread diseases. We investigated Dunlin (Calidris alpina), a sh
Authors
Mark P. Miller, Susan M. Haig, Thomas D. Mullins, Luzhang Ruan, Bruce Casler, Alexei Dondua, H. River Gates, J. Matthew Johnson, Steven J. Kendall, Pavel S. Tomkovich, Diane Tracy, Olga P. Valchuk, Richard B. Lanctot

Mortality estimation from carcass searches using the R-package carcass: a tutorial

This article is a tutorial for the R-package carcass. It starts with a short overview of common methods used to estimate mortality based on carcass searches. Then, it guides step by step through a simple example. First, the proportion of animals that fall into the search area is estimated. Second, carcass persistence time is estimated based on experimental data. Third, searcher efficiency is estim
Authors
Fränzi Korner-Nievergelt, Oliver Behr, Robert Brinkmann, Matthew A. Etterson, Manuela M. P. Huso, Daniel Dalthorp, Pius Korner-Nievergelt, Tobias Roth, Ivo Niermann

Elk monitoring in Mount Rainier and Olympic national parks: 2008-2011 synthesis report

In 2008, the USGS collaborated with the NPS, the Muckleshoot and Puyallup Indian Tribes, and WDFW to develop a protocol tor monitor changes in abundance, population composition, and spatial distribution of elk on summer ranges in MORA and OLYM and winter ranges in OLYM. We developed double-observer sightability (DO-S) models that adjusted raw counts of elk as a function of factors influencing dete
Authors
Kurt J. Jenkins, Paul C. Griffin, Patricia J. Happe, Mason E. Reid, David J. Vales, Barbara J. Moeller, Michelle Tirhe, Scott McCorquodale, Katherine Beirne, John Boetsch, William Baccus, Bruce C. Lubow

Plant diversity predicts beta but not alpha diversity of soil microbes across grasslands worldwide

Aboveground–belowground interactions exert critical controls on the composition and function of terrestrial ecosystems, yet the fundamental relationships between plant diversity and soil microbial diversity remain elusive. Theory predicts predominantly positive associations but tests within single sites have shown variable relationships, and associations between plant and microbial diversity acros
Authors
Suzanne M. Prober, Jonathan W. Leff, Scott T. Bates, Elizabeth T. Borer, Jennifer Firn, W. Stanley Harpole, Eric M. Lind, Eric W. Seabloom, Peter B. Adler, Jonathan D. Bakker, Elsa E. Cleland, Nicole DeCrappeo, Elizabeth DeLorenze, Nicole Hagenah, Yann Hautier, Kirsten S. Hofmockel, Kevin P. Kirkman, Johannes M. H. Knops, Kimberly J. La Pierre, Andrew S. MacDougall, Rebecca L. McCulley, Charles E. Mitchell, Anita C. Risch, Martin Schuetz, Carly J. Stevens, Ryan J. Williams, Noah Fierer