Migratory Birds

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 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.

The Ridgway’s rail is a federal and state listed endangered species that occurs in wetlands along the Pacific Coast and from the Lower Colorado River drainage to southern Baja California. Three subspecies of Ridgway’s rail are found within the United States: the California Ridgway’s Rail, Yuma Ridgway’s rail, and Light-footed Ridgway’s rail. All three subspecies have declined since 1900 as a...

Dr. Barbara Kus is a partner in an international bird-monitoring program to provide long-term data throughout North America. MAPS or “Monitoring Avian Productivity and Survivorship”, uses capture and banding data to compile basic demographic parameters of migratory species, many of which are imperiled regionally and even globally. Age- and sex-specific data on annual survival, reproduction, and...

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...

Seabirds are Department of the Interior (DOI) Trust Species and are protected under the Migratory Bird Treaty Act and the Endangered Species Act. To support science-based decision capacity and Marine Spatial Planning (MSP) among U.S. Government resource managers, Dr. Josh Adams and the WERC seabird team have partnered with the Bureau of Ocean Energy Management, U.S. Fish and Wildlife Service...

Dr. Josh Adams and his science team at WERC study seabird health and support adaptive management by quantifying abundance patterns and behaviors associated with habitats at sea, where seabirds spend the overwhelming majority of their lives. Adams’s team also employs conservation science to support resource managers on land, where seabirds are obligated to nest. His group provides scientific...

The San Francisco Bay is designated as a site of hemispheric importance to shorebirds and annually supports over one million waterbirds. Within the USGS WERC waterbird breeding ecology program, Dr. Josh Ackerman and partners are studying habitat selection, movements, and factors influencing waterbird nest success and chick growth and survival.

The Suisun Marsh and Central Valley in California offer some of the world’s most important wetland habitats for waterfowl in the Pacific Flyway. Mike Casazza and USGS WERC biologists are providing the science to support and evaluate waterfowl populations and habitat management in North America.

Federally-listed as threatened since 1986, the Atlantic Coast Piping Plover (Charadrius melodus) population comprises fewer than 2,000 breeding pairs, according to the most recent census data. These breeding pairs are the target of the U.S. Fish and Wildlife Service’s (USFWS) species recovery plan.

The Upper Mississippi River System (UMRS) is an important stopover point for waterfowl during early-spring and late-fall migrations, particularly portions of the river between the Navigation Pools 4 and 13.This part of the Upper Mississippi River contains large areas of aquatic vegetation that include preferred food sources such as Arrowhead and Wild Celery. In addition, many of these areas are...

Loss of wetlands, invasive plants, and non-native predators pushed Hawaii’s waterbirds to the brink of extinction by the early 1900s, although population numbers have improved somewhat in recent decades with conservation efforts. Nonetheless, all Hawaiian waterbirds have global population sizes estimated around or below below 2,000 individuals, making them still highly vulnerable to extinction...