Aleutian tern

Aleutian tern
Conservation status
Least Concern (IUCN 3.1)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Charadriiformes
Family:	Sternidae
Genus:	Onychoprion
Species:	O. aleuticus
Binomial name
Onychoprion aleuticus (Baird, 1869)
Synonyms
Onychoprion aleutica (lapsus) Sterna aleutica Baird, 1869

The Aleutian tern (Onychoprion aleuticus, formerly Sterna aleutica - see Bridge et al., 2005) is a seabird of the tern family, Sternidae.

This species breeds in colonies on coasts and islands in Alaska and easternmost Siberia. It is strongly migratory, wintering off Indonesia and Malaysia. Large numbers appear off China during passage periods.

It is a very rare vagrant to western Europe, with just one record, on the Farne Islands off Northumberland, England on 28–29 May 1979.

It lays 2–3 eggs in a ground scrape. It sometimes nests among Arctic terns, which, like most white terns, are fiercely defensive of their nest and young and will attack large predators.

Like most other terns, the Aleutian tern feeds by plunge-diving for fish, usually from saline environments. The offering of fish by the male to the female is part of the courtship display.

This is a medium-sized tern, with a short, pointed bill and a long, deeply forked tail. It has a black cap with a white forehead, dark gray mantle and underparts and a mostly pale underwing with a dark secondary bar. It has a white rump and tail, black legs and a black bill.

The call is a musical whee-hee-hee.

References

• Bridge, E. S.; Jones, A. W. & Baker, A. J. (2005). A phylogenetic framework for the terns (Sternini) inferred from mtDNA sequences: implications for taxonomy and plumage evolution. Molecular Phylogenetics and Evolution 35: 459–469. PDF fulltext
• Collinson, M. (2006). Splitting headaches? Recent taxonomic changes affecting the British and Western Palaearctic lists. British Birds 99(6): 306-323.
• del Hoyo, J.; Elliott, A. & Sargatal, J. (editors) (1996). Handbook of birds of the world, Volume 3: Hoatzin to Auks. Lynx Edicions, Barcelona. ISBN 84-87334-22-9
• Harrison, Peter (1988). Seabirds (2nd edition). Christopher Helm, London ISBN 0-7470-1410-8
• National Geographic Society (2002). Field Guide to the Birds of North America. National Geographic, Washington DC. ISBN 0-7922-6877-6
• Sibley, David Allen (2000). The Sibley Guide to Birds. Alfred A. Knopf, New York. ISBN 0-679-45122-6