Forster's tern

Forster's tern
Conservation status
Least Concern  (IUCN 3.1)[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Charadriiformes
Family:	Sternidae
Genus:	Sterna
Species:	S. forsteri
Binomial name
Sterna forsteri Nuttall, 1834

The Forster's tern (Sterna forsteri) is a member of the tern family, Sternidae. It breeds inland in North America and winters south to the Caribbean and northern South America.

This species is rare but annual in western Europe, and has wintered in Ireland and Great Britain on a number of occasions. No European tern winters so far north.

This species breeds in colonies in marshes. It nests in a ground scrape and lays three or more eggs. Like all white terns, it is fiercely defensive of its nest and young.

The Forster's tern feeds by plunge-diving for fish, but will also hawk for insects in its breeding marshes. It usually feeds from saline environments in winter, like most Sterna terns. It usually dives directly, and not from the "stepped-hover" favoured by the Arctic tern. The offering of fish by the male to the female is part of the courtship display.

This is a small tern, 33–36 cm (13–14 in) long with a 64–70 cm (25–28 in) wingspan. It is most similar to the common tern. It has pale grey upperparts and white underparts. Its legs are red and its bill is red, tipped with black. In winter, the forehead becomes white and a characteristic black eye mask remains. Juvenile Forster's terns are similar to the winter adult. The call is a harsh noise like a black-headed gull.

This species is unlikely to be confused with the common tern in winter because of the black eye mask, but is much more similar in breeding plumage. Forster's has a grey centre to its white tail, and the upperwings are pure white, without the darker primary wedge of the common tern.

This bird is named after the naturalist Johann Reinhold Forster.

Gallery

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  Breeding

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  Nonbreeding

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  Forster's tern fishing on Lake Mattamuskeet

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  ID composite

References

1. BirdLife International (2012). "Sterna forsteri". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.

• "National Geographic" Field Guide to the Birds of North America ISBN 0-7922-6877-6
• Seabirds by Harrison, ISBN 0-7099-1207-2
• Terns of Europe and North America by Olsen and Larsson, ISBN 0-7136-4056-1

External links

• Forster's Tern Species Account - Cornell Lab of Ornithology
• Forster's Tern - Sterna forsteri - USGS Patuxent Bird Identification InfoCenter
• Field Guide Page on Flickr
• Forster's Tern videos, photos, and sounds at the Internet Bird Collection
• Forster's Tern photo gallery at VIREO (Drexel University)
• Interactive range map of Sterna forsteri at IUCN Red List maps