Sandwich Tern | ||||||||||||||
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Scientific classification | ||||||||||||||
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Binomial name | ||||||||||||||
Sterna sandvicensis |
The Sandwich Tern, Sterna sandvicensis, is a seabird of the tern family Sternidae. This bird has three races.
S. s. sandvicensis breeds on the Atlantic and Mediterranean coasts of Europe, and winters off western Africa and Arabia. The smaller S. s. acuflavida breeds on Atlantic coasts of North America, wintering in the Caribbean and further south, and has wandered to western Europe. Yellow-billed S. s. eurygnatha breeds from the Caribbean southwards along Atlantic South America.
This species breeds in colonies on coasts and islands and often inland on suitable waters. It nests in a ground scrape and lays one to three eggs. Like all white terns, it is fiercely defensive of its nest and young and will attack humans and other large predators, usually attacking the back of the head.
Like all Sterna terns, Sandwich Tern feeds by plunge-diving for fish, usually from saline environments. It usually dives directly, and not from the "stepped-hover" favoured by Arctic Tern. The offering of fish by the male to the female is part of the courtship display.
This is a large-medium tern, unlikely to be confused within most of its range, although the Caribbean form could be confused with the Elegant Tern.
Its thin sharp bill is black with a yellow tip, except in the yellow or orange billed Caribbean race. Its short legs are black. Its upperwings are pale grey and its underparts white, and this tern looks very pale in flight, although the primary flight feathers darken during the summer. The call is a characteristic loud grating noise.
In winter, the forehead becomes white. Juvenile Sandwich Terns have a scaly appearance like juvenile Roseate Terns.