Wildlife and Terrestrial Species

This project improves our understanding of the ecology of reptiles in California and evaluates methods of managing landscapes and these imperiled species. In particular, Dr. Brian Halstead examines the distribution and demography of reptiles to understand factors that affect where they are found and how populations change. He further explores the relationships of reptiles with their abiotic and...

Amphibian populations have declined in many areas around the world. Initially, there was skepticism as to whether the observed declines were merely minor population fluctuations, but it has become increasingly clear that many declines are both real and sustained. At the request of the U.S. Department of the Interior, USGS Western Ecological Research Center (WERC) scientists are supporting the...

Desert landscapes are rapidly changing due to increases in invasive plant species, frequency of wildfires, urban and energy development, recreational use, military training, and climate variation. Dr. Todd Esque, USGS researchers, and collaborators are working together to investigate these changes and provide managers with key information that can be used to manage natural resources more...

WERC's Dr. Amy Vandergast and colleagues merge genetic data with mapping and modeling tools to inform biodiversity conservation efforts. They define evolutionary significant units within species, reveal evolutionary mechanisms responsible for diversification, and identify regions with high genetic diversity for protection.

The primary goal of this bat research program is to develop projects that increase our understanding of basic ecology and natural history of western bat species, while simultaneously providing needed data to inform conservation measures and management decisions in the West. Dr. Brian Halstead, together with Gabriel Reyes, studies the habitat and resource selection, movement ecology, demography...

Western U.S. wetlands provide critical habitat for wintering and breeding waterfowl in California. WERC's Dr. Josh Ackerman is working toward collecting data to understand factors influencing duck nest success, to improve and restore breeding habitat for resident duck populations in California, and understand composition of predator communities. To learn more about how USGS WERC is implementing...

The California Sea Otter Stranding Network is part of the USGS effort to monitor southern sea otters (Enhydra lutris nereis) and provide data to the U.S. Fish and Wildlife Service. WERC's sea otter team works with multiple institutions and partners to report, recover, and examine stranded sea otters. In addition, instructions on how to report a stranded sea otter are included in this webpage.

At the population level, Dr. Amy Vandergast and her team estimates important population parameters such as effective migration (or gene flow) and the number of breeding adults (or effective population size), and quantify the impacts of landscape changes and disturbance on these parameters. This work informs individual species management.

California’s Central Valley and San Francisco Bay Estuary have a long history of mercury contamination from past mercury mining and gold extraction. Waterbirds are particularly susceptible to mercury because of their use of wetland habitats where methylmercury (the most toxic and biologically available form) is produced and relatively low methylmercury exposure can reduce reproductive success...

The desert tortoise is listed as “threatened” under the Endangered Species Act. USGS WERC scientists, along with project partners have been conducting long-term analyses on how changes in the southwestern deserts of the United States can affect desert tortoise populations. Dr. Todd Esque and his team are investigating how habitat disturbances and restoration projects influence tortoise populations...

The coastal California Gnatcatcher ( Polioptila californica californica), a federally threatened species, is considered a flagship species for southern California conservation planning. Dr. Barbara Kus collaborates with Dr. Amy Vandergast and local agencies to provide information to managers that can be used to conserve this species and its habitat.

This project improves our understanding of the ecology of amphibians in northern California and evaluates methods of managing landscapes and these imperiled species. In particular, Dr. Brian Halstead examines the distribution and demography of amphibians to understand factors that affect where amphibians are found and how populations change. He further explores the relationships of amphibians with...