Caspian Terns on Island at NWR

Caspian terns (Hydroprogne caspia) on Island 11 in Pond A16, Don Edwards San Francisco Bay National Wildlife Refuge, California. USGS biologists, at the request of the U.S. Army Corps of Engineers and U.S. Fish and Wildlife Service, used lifelike models of Caspian terns to attract these waterbirds to newly-constructed habitat in the Bay.