USGS partners at the U.S. Fish and Wildlife Service, U.S. Army Corps of Engineers and U.S. Bureau of Reclamation modified recently-constructed islands to provide nesting habitat for Caspian terns (pictured) at the Don Edwards San Francisco Bay National Wildlife Refuge. This is part of an effort to move nesting Caspian terns out of the Columbia River Basin, where they prey on salmon listed under the Endangered Species Act.  

But how to encourage Caspian terns to relocate to the islands? Biologists from the USGS Western Ecological Research Center placed lifelike models (in foreground) of Caspian terns on the islands, along with electronic systems that played recordings of tern calls. From 2015 to 2017, the team monitored the size, productivity, and growth of these new Caspian tern colonies.

Over the space of three years, these efforts resulted in more than 1,300 nests and more than 500 fledglings produced on these islands. The success of this “social attraction” study can help other scientists and resource managers invite more wildlife to recovering habitat in the Bay.

Link to the new study: https://go.usa.gov/xUudY

Link to the project webpage: https://go.usa.gov/xUud4