WatchList Species Account for Aleutian Tern (Sterna aleutica)

Qualifies for the list as a Declining Yellow List Species


Aleutian Tern
Photo: Glen Tepke

The Aleutian Tern nests in loose colonies sparsely distributed along the coasts of southern and western Alaska, including the Copper River Delta, and eastern Siberia. It often nests with Arctic Terns in Alaska and Common Terns in Siberia. It sometimes nests near Mew Gull colonies. The tern now nests on eight islands in the Aleutians, probably due to removal of red and arctic foxes by the U.S. Fish and Wildlife Service. Its winter range is largely unknown, but it may winter at sea in the South Pacific near Australia and the Philippines.


Estimated population sizes are 9-12,000 birds breeding in Alaska and
7-13,000 birds in Siberia. Reproductive success at colonies can be very low due to heavy predation on eggs and chicks by a variety of mammals (besides foxes, these include coyotes, dogs, river otters, weasels, brown bears, and rats) and birds (including Bald Eagles, Parasitic Jaegers, Glaucous-winged and Mew Gulls, Short-eared Owls, Black-billed Magpies, Northwestern Crows, and Common Ravens).


Other threats to the nesting birds are human disturbance through egg harvest, through reindeer herding, and through spring burning of grasses.