Species Status Assessments

Barrier islands provide numerous invaluable ecosystem goods and services including storm protection and erosion control for the mainland, habitat for fish and wildlife, salinity regulation in estuaries, carbon sequestration in marshes, recreation, and tourism. These islands are dynamic environments due to their position at the land-sea interface. Storms, wave energy, tides, currents, and relative...

Impact of UMESC Science This research aims to quantify spatial patterns of adult and juvenile (≤5 y of age) freshwater mussels across multiple scales based on systematic survey data from 4 reaches of the Upper Mississippi River (Navigation Pools 3, 5, 6, and 18). Resource managers can use this critical information about spatial structure to make informed river management decisions.

The Interagency Grizzly Bear Study Team (IGBST) is an interdisciplinary group of scientists and biologists responsible for long-term monitoring and research efforts on grizzly bears in the Greater Yellowstone Ecosystem (GYE). The team was formed by the Department of the Interior (DOI) in 1973 as a direct result of controversy surrounding the closure of open pit garbage dumps within Yellowstone...

Genetic and demographic analyses are key to understanding mechanisms of population and species declines and recovery potential. They are equally important to managers assessing risk of extinction relative to the provisions of the Endangered Species Act, and for establishing recovery goals and planning recovery actions. In addition to the methodologically and conceptually complex nature of these...

Special status species and habitats are often sentinels of accelerated ecosystem change and, by definition, are priorities for protection, restoration, or focused management.

Many species of amphibians and reptiles are declining or facing population threats in the West related to habitat loss, habitat alteration, introduction of non-native species, and other factors. Our work focuses on the status and trends of resident herpetofauna and how to better manage their habitats. Much of the effort is undertaken with cooperators, particularly with other agencies in the...

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...

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.

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.

Dr. Kathleen Longshore’s goal is to understand how predator/prey relationships, disease and human-caused disturbance work separately and synergistically to impact bighorn sheep populations under variable ecological stress. Information from this project will provide managers with an understanding of specific and regional impacting factors that contribute to impact variation in population trends.