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Publications

Filter Total Items: 1990

Region-wide ecological responses of arid Wyoming big sagebrush communities to fuel treatments

If arid sagebrush ecosystems lack resilience to disturbances or resistance to annual invasives, then alternative successional states dominated by annual invasives, especially cheatgrass (Bromus tectorum L.), are likely after fuel treatments. We identified six Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis Beetle & Young) locations (152–381 mm precipitation) that we believed had suff
Authors
David A. Pyke, Scott E. Shaff, Andrew I. Lindgren, Eugene W. Schupp, Paul S. Doescher, Jeanne C. Chambers, Jeffrey S. Burnham, Manuela M. Huso

Successes and challenges from formation to implementation of eleven broad-extent conservation programs

Integration of conservation partnerships across geographic, biological, and administrative boundaries is increasingly relevant because drivers of change, such as climate shifts, transcend these boundaries. We explored successes and challenges of established conservation programs that span multiple watersheds and consider both social and ecological concerns. We asked representatives from a diverse
Authors
Erik A. Beever, John B. Bradford, Matthew J. Germino, Brady J. Mattsson, Max Post van der Burg, Mark Brunson

Quantifying restoration effectiveness using multi-scale habitat models: implications for sage-grouse in the Great Basin

A recurrent challenge in the conservation of wide-ranging, imperiled species is understanding which habitats to protect and whether we are capable of restoring degraded landscapes. For Greater Sage-grouse (Centrocercus urophasianus), a species of conservation concern in the western United States, we approached this problem by developing multi-scale empirical models of occupancy in 211 randomly loc
Authors
Robert S. Arkle, David S. Pilliod, Steven E. Hanser, Matthew L. Brooks, Jeanne C. Chambers, James B. Grace, Kevin C. Knutson, David A. Pyke, Justin L. Welty

Accounting for unsearched areas in estimating wind turbine-caused fatality

With wind energy production expanding rapidly, concerns about turbine-induced bird and bat fatality have grown and the demand for accurate estimation of fatality is increasing. Estimation typically involves counting carcasses observed below turbines and adjusting counts by estimated detection probabilities. Three primary sources of imperfect detection are 1) carcasses fall into unsearched areas, 2
Authors
Manuela M.P. Huso, Dan Dalthorp

Herbivores and nutrients control grassland plant diversity via light limitation

Human alterations to nutrient cycles and herbivore communities are affecting global biodiversity dramatically. Ecological theory predicts these changes should be strongly counteractive: nutrient addition drives plant species loss through intensified competition for light, whereas herbivores prevent competitive exclusion by increasing ground-level light, particularly in productive systems. Here we
Authors
Elizabeth T. Borer, Eric W. Seabloom, Daniel S. Gruner, W. Stanley Harpole, Helmut Hillebrand, Eric M. Lind, Peter B. Alder, Juan Alberti, T. Michael Anderson, Jonathan D. Bakker, Lori Biederman, Dana Blumenthal, Cynthia S. Brown, Lars A. Brudvig, Yvonne M. Buckley, Marc Cadotte, Cheng-Jin Chu, Elsa E. Cleland, Michael J. Crawley, Pedro Daleo, Ellen Ingman Damschen, Kendi F. Davies, Nicole M. DeCrappeo, Guozhen Du, Jennifer Firn, Yann Hautier, Robert W. Heckman, Andy Hector, Janneke HilleRisLambers, Oscar Iribarne, Julia A. Klein, Johannes M.H. Knops, Kimberly J. La Pierre, Andrew D.B. Leakey, Wei Li, Andrew S. MacDougall, Rebecca L. McCulley, Brett A. Melbourne, Charles E. Mitchell, Joslin L. Moore, Brent Mortensen, Lydia R. O'Halloran, John L. Orrock, Jesús Pascual, Suzanne M. Prober, David A. Pyke, Anita C. Risch, Martin Schuetz, Melinda D. Smith, Carly J. Stevens, Lauren L. Sullivan, Ryan J. Williams, Peter D. Wragg, Justin P. Wright, Louie H. Yang

Modeling marbled murrelet (Brachyramphus marmoratus) habitat using LiDAR-derived canopy data

LiDAR (Light Detection And Ranging) is an emerging remote-sensing tool that can provide fine-scale data describing vertical complexity of vegetation relevant to species that are responsive to forest structure. We used LiDAR data to estimate occupancy probability for the federally threatened marbled murrelet (Brachyramphus marmoratus) in the Oregon Coast Range of the United States. Our goal was to
Authors
Joan C. Hagar, Bianca N.I. Eskelson, Patricia K. Haggerty, S. Kim Nelson, David G. Vesely

Vocal activity as a low cost and scalable index of seabird colony size

Although wildlife conservation actions have increased globally in number and complexity, the lack of scalable, cost-effective monitoring methods limits adaptive management and the evaluation of conservation efficacy. Automated sensors and computer-aided analyses provide a scalable and increasingly cost-effective tool for conservation monitoring. A key assumption of automated acoustic monitoring of
Authors
Abraham L. Borker, Matthew W. McKown, Joshua T. Ackerman, Collin A. Eagles-Smith, Bernie R. Tershy, Donald A. Croll

Mercury in fishes from 21 national parks in the Western United States: inter- and intra-park variation in concentrations and ecological risk

Mercury (Hg) is a global contaminant and human activities have increased atmospheric Hg concentrations 3- to 5-fold during the past 150 years. This increased release into the atmosphere has resulted in elevated loadings to aquatic habitats where biogeochemical processes promote the microbial conversion of inorganic Hg to methylmercury, the bioavailable form of Hg. The physicochemical properties of
Authors
Collin A. Eagles-Smith, James J. Willacker, Colleen M. Flanagan Pritz

Diffuse migratory connectivity in two species of shrubland birds: evidence from stable isotopes

Connecting seasonal ranges of migratory birds is important for understanding the annual template of stressors that influence their populations. Brewer’s sparrows (Spizella breweri) and sagebrush sparrows (Artemisiospiza nevadensis) share similar sagebrush (Artemisia spp.) habitats for breeding but have different population trends that might be related to winter location. To link breeding and winte
Authors
Steven T. Knick, Matthias Leu, John T. Rotenberry, Steven E. Hanser, Kurt Fesenmyer

An analysis of monthly home range size in the critically endangered California Condor Gymnogyps californianus

Condors and vultures comprise the only group of terrestrial vertebrates in the world that are obligate scavengers, and these species move widely to locate ephemeral, unpredictable, and patchily-distributed food resources. In this study, we used high-resolution GPS location data to quantify monthly home range size of the critically endangered California Condor Gymnogyps californianus throughout the
Authors
James W. Rivers, Matthew J. Johnson, Susan M. Haig, Carl J. Schwarz, Joseph Burnett, Joseph Brandt, Daniel George, Jesse Grantham

Semi-automated identification of leopard frogs

Principal component analysis is used to implement a semi-automatic recognition system to identify recaptured northern leopard frogs (Lithobates pipiens). Results of both open set and closed set experiments are given. The presented algorithm is shown to provide accurate identification of 209 individual leopard frogs from a total set of 1386 images.
Authors
Dijana Petrovska-Delacrétaz, Aaron Edwards, John Chiasson, Gérard Chollet, David S. Pilliod

Resource selection by the California condor (Gymnogyps californianus) relative to terrestrial-based habitats and meteorological conditions

Condors and vultures are distinct from most other terrestrial birds because they use extensive soaring flight for their daily movements. Therefore, assessing resource selection by these avian scavengers requires quantifying the availability of terrestrial-based habitats, as well as meteorological variables that influence atmospheric conditions necessary for soaring. In this study, we undertook the
Authors
J. Matthew Johnson, Susan M. Haig, Carl J. Schwarz, John W. Glendening, L. Joseph Burnett, Daniel George, Jesse Grantham