Medium small. Graceful, long forked tail, with streamers extending well beyond wings when at rest. Slender bill. Sexes alike.
Adults: Breeding: Cap, black. Eye, dark brown. Back, most of wings, whitish-pearl grey. Outer primaries have black outer web and line on inner web next to shaft, trailing edge of primaries, white. Tail, whitish-pearl grey, the outer tail feathers white. Underparts, underwing, white with rose wash on breast and belly. Bill, red or red with a black tip or all black. Legs, orange-red. Non-breeding: Similar to breeding plumage but forehead and forecrown, white. Outermost three primaries blackish around shaft forming a dark leading edge to wing. Tail is shorter.
Immatures: Forehead, whitish. Remainder of cap, blackish-brown. Back, brownish-grey, feathers have distinct dark brown bars. Wings, pale grey with buff edges to feathers. Shoulder, blackish. Flight feathers dark brown, tipped white forming a distinct white trailing edge to wing.
Other Names (World)
Roseate Tern, Graceful Tern, Dougall's Tern
Derivation
Stern'-a - N.L., a gull: dougallii - Dr. Peter MacDougall of Glasgow (1777 - 1814), Scottish physician and naturalist who first observed this tern on islets in the Firth of Clyde in 1812
Habitat
Marine, visiting sand-cays, coral reefs and off-shore islands.
Anguilla (B), Antigua and Barbuda, Aruba (B) (NB), Australia (B), Bahamas, Belize (B), Brazil (NB), Canada (B), China (mainland) (B), Cuba (B) (NB), Dominica, Dominican Republic, France (B) (P), Ghana, Grenada, Guadeloupe (B), Guatemala (NB), Haiti, India (B), Indonesia (B), Ireland (B) (P), Japan, Kenya (B), Madagascar (B), Martinique, Mauritius (B), Mexico, Montserrat, Netherlands Antilles (NB), New Caledonia (B) (NB), Oman (B) (NB), Papua New Guinea (B) (NB), Portugal (B) (P), Puerto Rico (B) (NB), Seychelles (B), Solomon Islands (B) (NB), Somalia (B), South Africa (B), Spain (B) (NB), St Kitts and Nevis (B), St Lucia, St Vincent and The Grenadines, Taiwan (China) (B), Tanzania [United Republic of] (B), Trinidad and Tobago (B) (NB), Turks and Caicos Islands (B) (NB), United Kingdom (B), USA (B), Venezuela (B) (NB), Virgin Islands (British) (B), Virgin Islands (U.S.) (B).
Vagrant to Austria, Bahrain, Barbados, Belgium, Brunei Darussalam, Colombia, Denmark, Egypt, Gambia, Germany, Gibraltar, Israel, Libyan Arab Jamahiriya, Malta, Myanmar, Netherlands, Norway, Poland, St Pierre and Miquelon (NB), Sweden, Switzerland, United Arab Emirates, Vanuatu, Vietnam, Yemen.
Population
Estimated population is 70,000 - 82,000 (2010).
Roseate Tern (Sterna dougallii) [XC831862]
by Ricardo Hevia from Ortegal (near Cari\u00f1o), A Coru\u00f1a, Galicia, Spain (nocturnal flight call)
Roseate Tern (Sterna dougallii) [XC741005]
by Irish Wildlife Sounds from Carne, Wexford, County Wexford, Ireland (flight call)
Nest
A slight depression in sand or on a ridge of dead coral, sometimes lined with fine pieces of coral or shells. In colonies.
Eggs (Guide)
1 or 2; pale green, spotted and blotched umber, sepia and grey; ellipsoidal; about 38 x 29 mm. Incubation: 21 - 26 days; by both sexes but mainly female.
Young
Precocial, semi-nidifugous. Fledge in 22 - 30 days.
Subspecies
In some respects intermediate between Sterna and Thalasseus. Internal taxonomy in need of revision, as subspecific boundaries confused. Subspecies allocation of birds breeding on islets off eastern Africa requires study, perhaps closer to bangsi than to dougallii, although included in latter. Subspecies arideensis may not be distinct from bangsi. The variation of nominate dougallii encompasses almost entire range of variation of species.
The following 5 subspecies are recognised:
dougallii Montagu, 1813 - Nova Scotia to New York and Florida, south through Gulf of Honduras and West Indies to islands off northern Venezuela, and also Azores, north-western Europe, and eastern and southern Africa from southern Somalia to Tanzania and in southern Cape Province; American populations may winter mainly in mid-Atlantic, eastern Atlantic birds winter on coasts of tropical western Africa.
arideensis Mathews, 1912 - Seychelles south to Madagascar and east to Rodrigues I.
korustes (Hume, 1874) - Sri Lanka, Andaman Is and Mergui Archipelago (south-western Myanmar).
bangsi Mathews, 1912 - Arabian Sea, Ryukyu Is, coastal China and Taiwan south to Greater Sundas and east to southern New Guinea, Solomons, New Caledonia and possibly Fiji; presumably this subspecies on Cocos (Keeling) Is.
gracilis Gould, 1845 - Moluccas and Australia.
Similar Species
Common Tern (Sterna hirundo)
Larger. Upperparts greyer. Trailing edge to primaries are dark. Legs are black. Bill is black. Bill is not as fine. Tail streamers do not extend beyond wings at rest.
Arctic Tern (Sterna paradisaea)
Similar size. Breeding with breeding and non-breeding with non-breeding. Has shorter, bill, legs and tail. Has a dark trailing edge to primaries and a dark edge to outer tail-streamers.
Compare Images
The Field Guide to the Birds of Australia Pizzey, G., and Knight, E., 1997, Angus & Robertson, Sydney ISBN 0 207 19691 5
Field Guide to Australian Birds Morecombe, M., 2000, Steve Parish Publishing Pty Ltd. ISBN 1 876282 10 X
Field Guide to the Birds of Australia Simpson, K., and Day, N., 1999, 6th Edition, Viking ISBN 0 670 87918 5
Reader's Digest Complete Book of Australian Birds 1988, 2nd Edition, Reader's Digest ISBN 0 949819 99 9
What Bird is That? 1984, Revised Edition, Angus & Robertson, Sydney ISBN 0 207 14846 5
Handbook of Australian, New Zealand & Antarctic Birds 1990 - , Oxford University Press, Melbourne ISBN 0 19 553244 9