Skip to main content
U.S. flag

An official website of the United States government

Publications

Below is a list of WERC's peer-reviewed publications. If you are searching for a specific publication and cannot find it in this list, please contact werc_web@usgs.gov

Filter Total Items: 3617

Robust age estimation of southern sea otters from multiple morphometrics

Reliable age estimation is an essential tool to assess the status of wildlife populations and inform successful management. Aging methods, however, are often limited by too few data, skewed demographic representation, and by single or uncertain morphometric relationships. In this study, we synthesize age estimates in southern sea otters Enhydra lutris nereis from 761 individuals across 34 years of
Authors
Teri E. Nicholson, Karl A. Mayer, Michelle M. Staedler, Tyler O Gagne, Michael J. Murray, Marissa A Young, Joseph A. Tomoleoni, M. Tim Tinker, Kyle S. Van Houtan

A national-scale assessment of mercury bioaccumulation in United States National Parks using dragonfly larvae as biosentinels through a citizen-science framework

We conducted a national-scale assessment of mercury (Hg) bioaccumulation in aquatic ecosystems using dragonfly larvae as biosentinels, by developing a citizen science network to facilitate biological sampling. Implementing a carefully designed sampling methodology for citizen scientists, we developed an effective framework for landscape-level inquiry that might otherwise be resource limited. We as
Authors
Collin Eagles-Smith, James Willacker, Sarah J. Nelson, Collen M Flanagan Pritz, David P. Krabbenhoft, Celia Y. Chen, Joshua T. Ackerman, Evan H. Campbell Grant, David Pilliod

Height-related changes in forest composition, not tree vulnerability, explain increasing mortality with height during an extreme drought

Recently, Stovall et al.1 (hereafter SSY) showed that during an extreme drought, remotely sensed mortality of tall trees was more than double that of short trees. They interpreted this to be a consequence of inherently greater hydraulic vulnerability of tall trees, and suggested that tall-tree vulnerability should thus generalize more broadly. Here we reassess their conclusions using contemporan
Authors
Nathan L. Stephenson, Adrian Das

Gambel’s quail survey variability and implications for survey design in the Mohave Desert

Careful design of a wildlife population monitoring strategy is necessary to obtain accurate and precise results whether the purpose of the survey is development of habitat suitability models, to estimate abundance, or assess site occupancy. Important characteristics to consider in survey design are sources of elevated variability, particularly within‐subject variability, which increases the amount
Authors
Cory T. Overton, Michael L. Casazza, Daniel Connelley, Scott C. Gardner

A science business model for answering important questions

Perhaps the biggest question in science is how to do better science. Many ecologists, including this book’s editors and authors, have succeeded under the current science “business model” and, from our perspective, the status quo works well enough. But science business models are under increased scrutiny. For instance, since 2012, at least nine papers have critiqued government-sponsored biomedical
Authors
Kevin D. Lafferty

Changes in capture rates and body size among vertebrate species occupying an insular urban habitat reserve

Long‐term ecological monitoring provides valuable and objective scientific information to inform management and decision‐making. In this article, we analyze 22 years of herpetofauna monitoring data from the Point Loma Ecological Conservation Area (PLECA), an insular urban reserve near San Diego, CA. Our analysis showed that counts of individuals for one of the four most common terrestrial vertebra
Authors
Thomas Stanley, Rulon W. Clark, Robert N. Fisher, Carlton J. Rochester, Stephanie A Root, Keith J Lombardo, Stacey D Ostermann-Kelm

The Fire and Tree Mortality Database, for empirical modeling of individual tree mortality after fire

Wildland fires have a multitude of ecological effects in forests, woodlands, and savannas across the globe. A major focus of past research has been on tree mortality from fire, as trees provide a vast range of biological services. We assembled a database of individual-tree records from prescribed fires and wildfires in the United States. The Fire and Tree Mortality (FTM) database includes records
Authors
C. Alina Cansler, Sharon M. Hood, J. Morgan Varner, Phillip J. van Mantgem, Michelle C. Agne, Robert A. Andrus, Matthew P. Ayres, Bruce D. Ayres, Jonathan D. Bakker, Michael A. Battaglia, Barbara J. Bentz, Carolyn R. Breece, James K. Brown, Daniel R. Cluck, Tom W. Coleman, R. Gregory Corace, W. Wallace Covington, Douglas S. Cram, James B. Cronan, Joseph E. Crouse, Adrian Das, Ryan S. Davis, Darci M. Dickinson, Stephen A Fitzgerald, Peter Z. Fule, Lisa M. Ganio, Lindsay M. Grayson, Charles B. Halpern, Jim L. Hanula, Brian J. Harvey, J. Kevin Hiers, David W. Huffman, MaryBeth Keifer, Tara L. Keyser, Leda N. Kobziar, Thomas E. Kolb, Crystal A. Kolden, Karen E. Kopper, Jason R. Kreitler, Jesse K. Kreye, Andrew M. Latimer, Andrew P. Lerch, Maria J. Lombardero, Virginia L. McDaniel, Charles W. McHugh, Joel D. McMillin, Jason J. Moghaddas, Joseph J. O'Brien, Daniel D. B. Perrakis, David W. Peterson, Susan J. Pritchard, Robert A. Progar, Kenneth F. Raffa, Elizabeth D. Reinhardt, Joseph C. Restaino, John P. Roccaforte, Brendan M. Rogers, Kevin C. Ryan, Hugh D. Safford, Alyson E. Santoro, Timothy M. Shearman, Alice M. Shumate, Carolyn H. Sieg, Sheri L. Smith, Rebecca J. Smith, Nathan L. Stephenson, Mary Stuever, Jens Stevens, Michael T. Stoddard, Walter G. Thies, Nicole M. Vaillant, Shelby A. Weiss, Douglas J. Westlind, Travis J. Woolley, Micah C. Wright

Newly documented population extends geographic range and genetic diversity for the Leaf-toed Gecko (Phyllodactylus nocticolus) into the Transverse Ranges of southern California

Between 19 – 30 May 2018, one of us [AW] discovered a disjunct population of Peninsula leaf-toed geckos, Phyllodactylus nocticolus (Phyllodactylidae) on the northern edge of the Coachella Valley in the Little San Bernardino Mountains of the Transverse Ranges (Fig. 1a). The previously northernmost location for the species is Tahquitz Canyon, Riverside Co. (MVZ 212205) in the Peninsular Ranges 20 km
Authors
Dustin A. Wood, Alyssa Worrel-Black, Robert Black, Anna Mitelberg, Mark Fisher, Robert N. Fisher, A. G. Vandergast, Cameron W. Barrows

Historical museum collections and contemporary population studies implicate roads and introduced predatory bullfrogs in the decline of western pond turtles

The western pond turtle (WPT), recently separated into two paripatrically distributed species (Emys pallida and Emys marmorata), is experiencing significant reductions in its range and population size. In addition to habitat loss, two potential causes of decline are female-biased road mortality and high juvenile mortality from non-native predatory bullfrogs (Rana catesbeiana). However, quantitativ
Authors
E. Griffin Nicholson, Stephanie Manzo, Zachary Devereux, Thomas Morgan, Robert N. Fisher, Christopher W. Brown, Rosi Dagit, Peter A Scott, H. Bradley Shaffer

First recorded observations of conspecific egg and nestling consumption in common ravens (Corvus corax)

We observed cannibalism, the act of consuming a conspecific, of eggs and nestlings by Common Ravens (Corvus corax; hereafter “raven”) by video-monitoring nests in Nevada and California. Specifically, within the sagebrush steppe of Nevada, adult ravens killed and consumed raven chicks from an active nest. Additionally, on the coast of California, we observed adult ravens consume inviable eggs from
Authors
Joseph Atkinson, Peter S. Coates, Brianne E. Brussee, David J. Delehanty

Subspecies differentiation in an enigmatic chaparral shrub species

PremiseDelimiting biodiversity units is difficult in organisms in which differentiation is obscured by hybridization, plasticity, and other factors that blur phenotypic boundaries. Such work is more complicated when the focal units are subspecies, the definition of which has not been broadly explored in the era of modern genetic methods. Eastwood manzanita (Arctostaphylos glandulosa Eastw.) is a w
Authors
Yi Huang, Glen R. Morrison, Alan Brelsford, Janet Franklin, Diana D Jolles, Jon Keeley, V Thomas Parker, Natalie Saavedra, Andrew C Sanders, Thomas Stoughton, Gregory A. Wahlert, Amy Litt

Locality note for rubber boa

CHARINA BOTTAE BOTTAE (N. Rubber Boa), USA: CALIFORNIA: Monterey Co.: Landels-Hill Big Creek Reserve, east side of Hwy. 1, 80 km (50 miles) south of Carmel, Calif., (36.0719055 N 121.5991555 W) 19 June, 2009; (36.0703611 N 121.5982222 W) 06 July 2009; (36.9516666 N 121.5991944 W) 27 July 2009. In chronological order, photo vouchers MVZObs:Herp:26, MVZObs:Herp:27, MVZObs:Herp:28. Verified by
Authors
Joseph A. Tomoleoni, Richard F Hoyer