Western Ecological Research Center

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: 2,957
Year Published: 2019

Distinguishing recent dispersal from historical genetic connectivity in the coastal California gnatcatcher

Habitat loss and fragmentation are primary threats to biodiversity worldwide. We studied the impacts of habitat loss and fragmentation on genetic connectivity and diversity among local aggregations of the California gnatcatcher (Polioptila californica californica) across its U.S. range. With a dataset of 268 individuals genotyped at 19...

Vandergast, Amy G.; Kus, Barbara E.; Preston, Kristine L.; Barr, Kelly R.

Year Published: 2019

Freshwater tidal forests and estuarine wetlands may confer early life growth advantages for delta-reared Chinook Salmon

Large river deltas are complex ecosystems that are believed to play a pivotal role in promoting the early marine growth and survival of threatened Chinook Salmon Oncorhynchus tshawytscha. We used a fish bioenergetics model to assess the functional role of multiple delta habitats across a gradient of salinities and vegetation types, where...

Davis, Melanie J.; Woo, Isa; Ellings, Christopher S.; Hodgson, Sayre; Beauchamp, David A.; Nakai, Glynnis; De La Cruz, Susan E. W.

Year Published: 2019

Mercury contamination in resident and migrant songbirds and potential effects on body condition

Methlymercury is a significant risk to environmental health globally. We examined the ecological drivers of methylmercury bioaccumulation in songbirds and its effect on body condition while experimentally removing the potentially confounding and predominant effects of site and habitat. We measured blood and...

Ackerman, Joshua T.; Hartman, Christopher; Herzog, Mark P.

Year Published: 2019

Early-warning signals of individual tree mortality based on annual radial growth

Tree mortality is a key driver of forest dynamics and its occurrence is projected to increase in the future due to climate change. Despite recent advances in our understanding of the physiological mechanisms leading to death, we still lack robust indicators of mortality risk that could be applied at the individual tree scale. Here, we build on a...

Cailleret, Maxime; Dakos, Vasilis; Jansen, Steven; Robert, Elisabeth M. R.; Aakala, Tuomas; Amoroso, Mariano M.; Antos, Joe A.; Bigler, Christof; Bugmann, Harald; Caccianaga, Marco; Camarero, Jesus-Julio; Cherubini, Paolo; Coyea, Marie R.; Cufar, Katarina; Das, Adrian J.; Davi, Hendrik; Gea-Izquierdo, Guillermo; Gillner, Sten; Haavik, Laurel J.; Hartmann, Henrik; Heres, Ana-Maria; Hultine, Kevin R.; Janda, Pavel; Kane, Jeffrey M.; Kharuk, Viachelsav I.; Kitzberger, Thomas; Klein, Tamir; Levanic, Tom; Linares, Juan-Carlos; Lombardi, Fabio; Makinen, Harri; Mészáros, Ilona; Metsaranta, Juha M.; Oberhuber, Walter; Papadopoulos, Andreas; Petritan, Any Mary; Rohner, Brigitte; Sanguesa-Barreda, Gabriel; Smith, Jeremy M.; Stan, Amanda B.; Stojanovic, Dejan B.; Suarez, Maria-Laura; Svoboda, Miroslav; Trotsiuk, Volodymyr; Villalba, Ricardo; Westwood, Alana R.; Wyckoff, Peter H.; Martinez-Vilalta, Jordi

Year Published: 2019

Effects of prescribed fire on San Francisco gartersnake survival and movement

The application of fire is prescribed for management of habitats for many plant and animal communities, but its effects on herpetofauna are diverse and remain poorly understood. To date no studies have examined the effects of prescribed fire on endangered San Francisco gartersnake (Thamnophis sirtalis tetrataenia) populations, despite a call for...

Halstead, Brian J.; Thompson, Michelle E.; Amarello, Melissa; Smith, Jeffrey J.; Wylie, Glenn D.; Routman, Eric J.; Casazza, Michael L.

Year Published: 2019

Movements of female Sage Grouse Centrocercus urophasianus during incubation recess

We combined GPS data‐loggers, VHF transmitters, and DVR video‐monitoring to measure fine‐scale movement patterns during daily incubation recesses by female Sage Grouse Centrocercus urophasianus, a species with uniparental incubation that has experienced widespread population decline and distributional contraction. Most (69.6%) Sage Grouse...

Dudko, Jonathan E.; Coates, Peter S.; Delehanty, David J.

Year Published: 2019

Assessing effects of nonnative crayfish on mosquito survival

Introductions of nonnative predators often reduce biodiversity and affect natural predator–prey relationships and may increase the abundance of potential disease vectors (e.g., mosquitoes) indirectly through competition or predation cascades. The Santa Monica Mountains (California, U.S.A.), situated in a global biodiversity hotspot, is an area of...

Bucciarelli, Gary M.; Suh, Daniel; Davis Lamb, Avery; Roberts, Dave; Sharpton, Debra; Shaffer, H. Bradley; Fisher, Robert N.; Kats, Lee B.

Year Published: 2019

Drivers of chaparral type conversion to herbaceous vegetation in coastal Southern California

AimIn Southern California, native woody shrublands known as chaparral support exceptional biodiversity. However, large‐scale conversion of chaparral into largely exotic herbaceous cover is a major ecological threat and serious conservation concern. Due to substantial uncertainty regarding the causes and extent of this vegetation change, we aimed...

Syphard, Alexandra D.; Brennan, Teresa J.; Keeley, Jon E.

Year Published: 2019

Vertical zonation and niche breadth of tidal marsh plants along the Northeast Pacific coast

The distribution patterns of sessile organisms in coastal intertidal habitats typically exhibit vertical zonation, but little is known about variability in zonation among sites or species at larger spatial scales. Data on such heterogeneity could inform mechanistic understanding of factors affecting species distributions as well as efforts to...

Janousek, Christopher N.; Thorne, Karen M.; Takekawa, John Y.

Year Published: 2018

Changes in aquatic prey resources in response to estuary restoration in Willapa Bay, southwestern Washington

Executive SummaryThe ongoing restoration of more than 200 hectares of estuarine habitat at Willapa National Wildlife Refuge, southwestern Washington, is expected to benefit a variety of species, including salmonids that use estuarine and tidal marshes as rearing and feeding areas as well as migratory waterbirds. During March–June 2014 and 2015, U....

Woo, Isa; Davis, Melanie J.; De La Cruz, Susan E. W.
Woo, I., Davis, M.J., and De La Cruz, S., 2018. Changes in aquatic prey resources in response to estuary restoration in Willapa Bay, southwestern Washington: U.S. Geological Survey Open-File Report 2018-1194, 32 p., https://doi.org/10.3133/ofr20181194.

Year Published: 2018

Time-to-detection occupancy modeling: An efficient method for analyzing the occurrence of amphibians and reptiles

Occupancy models provide a reliable method of estimating species distributions while accounting for imperfect detectability. The cost of accounting for false absences is that detection and nondetection surveys typically require repeated visits to a site or multiple-observer techniques. More efficient methods of collecting data to estimate...

Halstead, Brian J.; Kleeman, Patrick M.; Rose, Jonathan

Year Published: 2018

Wildlife underpass use and environmental impact assessment: A southern California case study

Environmental planners often rely on transportation structures (i.e., underpasses, bridges) to provide connectivity for animals across developed landscapes. Environmental assessments of predicted environmental impacts from proposed developments often rely on literature reviews or other indirect measures to establish the importance of wildlife...

Longcore, Travis; Almaleh, Lindsay; Chetty, Brittany; Francis, Kathryn; Freidin, Robert; Huang, Ching-Sheng; Pickett, Brooke; Schreck, Diane; Scruggs, Brooke; Shulman, Elise; Swauger, Alissa; Tashnek, Alison; Wright, Michael; Boydston, Erin E.