Environmental Stressors

In 2017, the Western Ecological Research Center's seabird studies team developed a framework for quantifying seabird species vulnerability to offshore wind energy infrastructure in the Pacific Outer Continental Shelf portion of the California Current region. This tool supports marine resource-use planning by identifying sites where seabirds are most vulnerable and predicts how different species...

The Seabird Studies Team at the USGS Western Ecological Research Center is conducting aerial photographic surveys of the ocean off central and southern California to create comprehensive maps of seabird and marine mammal distributions. The project is supported by the Bureau of Ocean Energy Management and will inform planning in advance of potential offshore wind energy development along the...

We will examine evidence of heat stress in Yukon River Chinook salmon (Oncorhynchus tshawytscha) using heat shock proteins and gene expression.

Waterbirds such as shorebirds, waders, and ducks depend on healthy and productive estuaries to “fuel up” for long distance migrations along the Pacific Flyway. Estuarine ecosystems include a mosaic of managed, natural, and restoring wetlands, and provide critical stop-over and wintering areas for federally protected migratory bird species. USGS WERC’s Dr. Susan De La Cruz works with federal, state...

In 2012, scientists noticed that nearly a third of polar bears sampled in a study in Alaska were suffering from hair loss and poor health. Drs. Lizabeth Bowen and A. Keith Miles of WERC used new technology to track down and identify the factors responsible for driving disease in Alaskan polar bears.

With sea level rise, how will the coastal habitats of the San Francisco Bay Estuary change over the next 100 years? Mapping and modeling studies by Dr. Karen Thorne, WERC scientists, and partners have produced scenarios for this important coastal ecosystem.

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...

Fuel conditions and fire regimes in western forests and deserts have been altered due to past land management, biological invasions, and recent extreme weather events and climate shifts. These changes have created extreme fire risk to local and regional communities, threatening their economic health related to wildland recreation, forest production, livestock operations, and other uses of public...

Riparian woodlands are highly productive ecosystems that support a disproportionately high fraction of regional biodiversity. They are also one of the most endangered terrestrial systems in temperate North America, and have been reduced to just 5% of their former extent in California and throughout the American southwest. These losses have been accompanied by steep declines in numerous plant and...

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...

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 southwestern desert region is home to many sensitive species. Species are at-risk due to past, present, and future changes to the landscape. WERC’s Dr. Todd Esque, field researchers, and collaborators are using models, monitoring plans, and decision-support tools to provide land managers with the resources they need to answer questions about how environmental change influences plants, animals...