The Aleutian Tern is a coastal, colonial nesting seabird of Alaska and e. Siberia, with known breeding colonies distributed sparsely over a wide range (Figure 1). Discovered in 1868 on Kodiak I., Alaska, this species has been little studied to date, although the limited quantity of original data available for it has been synthesized several times (e.g., Bent 1921 , Gabrielson and Lincoln 1959 , Harrison 1983b , Craig Harrison 1984c , Cramp 1985a , Haney et al. 1991a ).
On its breeding grounds, this tern frequently associates with Arctic Terns (Sterna paradisaea) in North America and Common Terns (S. hirundo longipennis) in Siberia. Its distribution and abundance, breeding phenology, and habitat use are fairly well known, but its behaviors are not well described, although the species seems to share behaviors common to most tern species. Its molts and plumages, migrations, patterns of survival and mortality, and winter ranges are largely unknown. This species was believed to winter in the North Pacific Ocean, but specimens from the Philippines (subadults collected in May 1984) and sightings in Hong Kong (adults in fall of 1992) support speculation that it winters in the South Pacific near Australia and the Philippines.
In Eurasia, the Aleutian Tern is known also as the Kamchatka Tern ( Portenko 1973 ) or the White-fronted Tern ( Dement'Ev and Gladkov 1951 ), the latter name proposed because the species was then unknown from the Aleutian Islands. Thus Craig Harrison ( Harrison 1984c ) listed “White-fronted Tern” as an alternate name for the Aleutian Tern. Nevertheless, this species should not be confused with the White-fronted Tern (S. striata) of southeastern Australia and New Zealand, a separate species (see Harrison 1983b ).