The California Least Tern, Sterna antillarum browni, is the country's smallest tern, and is listed by the U.S. Government as an endangered, migratory species. Because it nests in sand dunes along beaches and bays and because 90% of California's coastal wetlands have been destroyed by development, it has only limited nesting areas, some of which have been set aside in the San Diego area. Humans and other destructive forces are excluded from such preserves. These terns may frequently be seen hovering above their prey and then plunge-diving into the bay or ocean to catch a meal of small fish. Least terns migrate from the San Diego area in the late fall, although a number of first-year birds may be seen feeding throughout the winter and are mature enough to care for themselves.