Tern (Little) Sternula albifrons

Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Charadriiformes
Family: Sternidae
Genus: Sternula
Species: S. albifrons
Binomial name: Sternula albifrons
Synonyms: Sterna albifrons
Common name: Little tern

Sternula albifrons is a little migrating tern of which there are three subspecies spread through Europe, Africa, Asia and Australia. The birds seen in New Zealand come from two different populations; most of them are northern hemisphere migrants that spend their non-breeding season in New Zealand but a few are from the population breeding in Australia and they can be recognised by having a moult cycle that is six months different. The Australian visitors are of the subspecies Sternula albifro sinensis.
Their habits are coastal environments, including beaches, sheltered inlets, estuaries, and harbours, especially where exposed sandbanks occur.

The Little tern is very similar in size, shape and plumage to the rare NZ fairy tern (Sternula nereis davisae). The tail is moderately long and forked and is slightly shorter than the wing-tips when the bird is at rest. They are a very light pale grey on the back and upper wings and white on the rump, tail and underparts. A black cap is separated from the bill by an extensive white forehead. The black eyes are in a narrow black wedge that terminates at the base of the bill. Their body length is 25cm (bill tip to tail) and its wingspan is 45-55 cm and weighs 50 gm. The yellow bill is thin and sharp and it has a black tip. The legs are yellow. Like most other white terns, the little tern feeds by plunge-diving for fish, usually from saline environments.

Sternula albifrons.jpg  

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