Sooty Tern Field ID Keys

Shape & Size

A fairly big tern with long wings.

Colour Pattern

A black and white tern with sooty-black upperparts, including rump, tail and cap and with white underparts. Its legs and bill are also black. It shows a large white triangular patch on forehead extending to above eye but not back over it.

Behavior

It has a powerful flight and it often soars and wheels high into the air, diving down to pick up food from the surface but rarely plunge-dives.

Habitat

This tern is seen along tropical and subtropical waters and islands of the Indian, Pacific and Atlantic Oceans. It is a vagrant bird to West Europe breeding in offshore islands. In Madeira archipelago only a pair breeds in Selvagem Pequena. Outside breeding season is a pelagic bird.

Distinction from similar species

It is very similar to the smaller Bridled Tern and the main distinct feature will be the amount of white at the forehead which does not extend behind the eye on the Sooty Tern while on the Bridled Tern it forms a supercilium

Onychoprion fuscatus Biometrics

Wingspan: 86 - 94 cm (Harrison, 1985)
Total length: 43 - 45 cm (Harrison, 1985)

Other Bird Facts

Seasonality in Madeira: Summertime but not every year
Breeding: Its nests are simple, with unlined scrapes or in depressions on
sand or rock in offshore islets. On its single brood lays a single egg incubated by both adults for about one month.
Diet: As a pelagic bird it feed on small fish and crustaceans at the sea surface

Status

Madeira local status by Correia-Fagundes et al, 2021: Very Rare breeding bird
Madeira local status by Romano et al, 2010: Very Rare breeding bird
Madeira local status by Zino et al, 1995: Rare breeding bird
Conservation status by the IUCN Red List Categories, 2013: Least Concern ver 3.1

Name of this species in other languages

Madeiran:Garajau-escuro
Portuguese: Gaivina-de-dorso-preto, Andorinha-do-mar-escura, Trinta-réis-das-rocas
German: Rußseeschwalbe
Dutch: Bonte Stern
Swedish: Sottärna
Danish: Sodfarvet Terne
Finish: Nokitiira
Norwegian: Sotterne
Spanish: Charrán Sombrío
French: Sterne fuligineuse
Italian: Rondine di mare oscura
Polish: Rybitwa czarnogrzbieta
Slovak: Rybár čiernochrbtý
Czech: Rybák černohřbetý
English synonyms: Wideawake Tern
Latin synonyms: Sterna fuscata