Sterna Terns

A large group of about 32 species of which the members can be found all over the world. Some species, such as the Caspian Tern are monotypic cosmopolitan birds, other are confined to restricted areas. Many species are split up in several subspecies. All of them have in common a narrow pointed bill, varying in color form black to bright red and yellow, sometimes with a white or blackish point. The Caspian is the largest with a large bill almost of the size of a Herring Gull, the smallest is the Little or Least Tern measuring hardly bigger than a Starling. Many species are very migratory. The Arctic Tern for instance migrates from the high Arctic where it breeds to the Antarctic pack ice during the southern summer.

Genus Sterna

Caspian Tern
Sterna caspia
St. Louis, Senegal
Culmen: 78.6 mm; total: 151.0 mm.
Unsexed adult

  • Caspian Tern Sterna caspia. Almost cosmopolitan.
  • Indian River Tern Sterna aurantia. Asiatic inland species.
  • South American Tern Sterna hirundinacea. Both South American coasts.
  • Common Tern Sterna hirundo. Three subspecies throughout northern temperate zone, moving to Southern Hemisphere in  winter.:
    • S. h. hirundo. Eastern and central North America, Europe, Middle East to Siberia.
    • S. h. longipennis, Breeding Northeast Asia.
    • S. h. tibetana, Breeding Kashmir, Tibet, Mongolia and China.

Common Tern
Sterna hirundo hirundo
The Netherlands
Culmen: ca. 38 mm, total: 81.5 mm.
Unsexed adult.

Arctic Tern
Sterna paradisea
Terschelling, The Netherlands
Culmen: 31.2 mm, total: 69.4 mm.
Adult female.

  • Arctic Tern Sterna paradisea. Circumpolar in Arctic and subarctic region, dispersing to Antarctic region.
  • Antarctic Tern Sterna vittata. Four subspecies, almost circumpolar in the South:
    • S. v. vittata. Breeding islands southern Indian Ocean.
    • S. v. tristanensis, Breeding Tristan dan Cunha group.
    • S. v. georgiae. Breeding South Georgia.
    • S. v. bethunei. Breeding subantarctic islands off New Zealand.
  • Forster's Tern Sterna forsteri, confined to North America.
  • Trudeau's Tern or Snowy-crowned Tern Sterna trudeaui, confined to southern South America.

Dougall's Tern
Sterna dougalli
Praia Islet, Graciosa, Azores 1)
Culmen: 38.4 mm, total: 78.5 mm.
Unsexed adult

White-fronted Tern
Sterna striata
Kaikoura, SI, New Zealand
Culmen: ca. 39 mm, total: 84.3 mm.
Unsexed adult

  • Roseate or Dougall's Tern Sterna dougallii. Widespread in the Old World, five subspecies:
    • S. d. dougallii. Eastern North America to Caribbean, Europe and Africa.
    • S. d. ariidensis. East Africa, Seychelles
    • S. d. bangsi. Arabian Sea to Far East.
    • S. d. gracilis. Australia and New Caledonia.
    • S. d. korustes. Bay of Bengal from India to Burma, Sri Lanka.
  • White-fronted Tern Sterna striata. New Zealand and south-east Australia.
  • White-cheeked Tern Sterna repressa. North-east Indian Ocean.
  • Black-naped Tern Sterna sumatrana. Two subspecies in tropical Indian and Pacific Ocean.
    • S. s. sumatrana. Malay region, Japan, north-east Australia to Samoa.
    • S. s. mathewsi. Madagascar, Seychelles and Chagos Is., wandering to South Africa.
  • Black-bellied Tern Sterna melanogastra, fresh water species from India to Indochina.
  • Aleutian Tern Sterna aleutica, eastern Siberia and Alaska.
  • Grey-backed Tern or Spectacled Tern Sterna lunata, central Pacific Ocean.
  • Bridled Tern or Brown-winged Tern Sterna anaethetus. Widespread in tropical oceans, four subspecies:
    • S. a. anaethetus. Eastern Indian Ocean.
    • S. a. melanoptera, Caribbean to West Africa.
    • S. a. antarctica. Western Indian Ocean.
    • S. a. nelsoni. Pacific Coast of Mexico and Central America.

Sooty Tern
Sterna fuscata fuscata

  • Sooty Tern or Wideawake Sterna fuscata. Seven subspecies in tropical belt:
    • S. f. fuscata. Caribbean to West Africa.
    • S. f. oahuensis. Tropical North Pacific.
    • S. f. crissalis. West Mexican islands to Galapagos Archipelago.
    • S. f. luctuosa. Islands off Chilean coast.
    • S. f. serrata. West and North Australia, Pacific to Easter Island.
    • S. f. kermadeci. Kermadec Islands.
    • S. f. nubilosa. Arabian Peninsula, Indian Ocean to Japan
  • Fairy tern or Nereis Tern Sterna nereis. Australasian region, four subspecies:
    • S. n. nereis, southern Australia, Tasmania.
    • S. n. honi, West Australia.
    • S. n. exsul, New Caledonia.
    • S. n. davisae, Northland, New Zealand.
  • Black-fronted Tern Sterna albostriata. Confined to New Zealand.
  • Amazon Tern or Yellow-billed Tern Sterna supercilliaris. Confined to eastern South America.
  • Damara Tern Sterna balearum. West coast of southern Africa.
  • Peruvian Tern or Chilean Tern Sterna lorata. Restricted to desert coasts of western South America.

Little Tern
Sterna albiforns albifrons
Location unknown

  • Little Tern Sterna albifrons. Cosmopolitan, five subspecies:
    • S. a. albifrons. Europe, Mediterranean to India.
    • S. a. mexicana. Mexico.
    • S. a. staebleri. Mexico.
    • S. a. guineae. West and Central Africa.
    • S. a. sinensis. Southeast and East Asia to Australia and Tasmania.
  • Least Tern Sterna antillarum. Caribbean area. Three subspecies:
    • S. a. antillarum. Eastern North America.
    • S. a. browni,  Mexico, Pacific USA
    • S. a. athalossos. Inland USA, Missisippi basin North America.
  • Saunder's Tern Sterna saundersi, former subspecies of S. albifrons, Red Sea, Seychelles, Madagascar.
  • (Great) Crested Tern or Swift Tern Sterna bergii. Five subspecies:
    • S. b. bergii. South Africa and Namibia.
    • S. b. enigma. Mozambique.
    • S. b. velox. Red and Arabian Sea to Somalia and Malay Peninsula.
    • S. b. cristata. Australia, Southwest Asia to Japan.
    • S. b. thalassina. East Africa, islands off East Africa and Indian Ocean.

Swift or Crested Tern
Sterna bergii
Culmen: 62.3 mm; total: 117.8 mm.
Unsexed adult

Royal Tern
Sterna maxima albidorsalis
Morocco, 1996
Culmen; 65.1 mm; total: 124.2 mm
Unsexed adult

  • Royal Tern Sterna maxima. Two subspecies:
    • S. m. maxima. Southern North America and Central America.
    • S. m. albidorsalis. West Africa.
  • Lesser Crested Tern Sterna bengalensis. Three subspecies and intermediate forms in Asia minor:
    • S. b. bengalensis. Red Sea, East Africa to India and Sri Lanka.
    • S. b. torresi. (Persian Gulf, Pakistan intermediate forms), Indonesia,  Australia and New Guinea.
    • S. b. emigrata. Mediterranean Sea.
  • Chinese Crested Tern Sterna bernsteini, coast of China and Phillipines.
  • Elegant Tern Sterna elegans, Pacific coast of Mexico and California.
  • Cayenne Tern Sterna euygnatha, confined to eastern South America. Formerly subspecies of S. sandvicensis.
  • Cabot's Tern S. acuflavides. North America, Atlantic coast to the Gulf states, wintering down to Uruguay.
  • Sandwich Tern Sterna sandvicensis. Two subspecies:
    • S. s. sanvicensis. Eurasia, from Britain, Mediterranean to Caspian Sea. Wintering south to South Africa

Sandwich Tern
Sterna sandvicensis sandivicensis
Vlieland, The Netherlands
Culmen: 53.4 mm, total: 105.0 mm.
Adult female.