Elegant Tern

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{{Taxobox | color = pink | name = Elegant Tern | status = Conservation status: Lower risk (nt) | regnum = Animalia | phylum = Chordata | classis = Aves | ordo = Charadriiformes | familia = Sternidae | genus = Sterna | species = S. elegans | binomial = Sterna elegans | binomial_authority = Gambel, 1849 }} The Elegant Tern (Sterna elegans or sometimes Thalasseus elegans) is a seabird of the tern family Sternidae. It breeds on the Pacific coasts of the southern USA and Mexico and winters south to Peru, Ecuador and Chile.

Surprisingly, this Pacific species has wandered to western Europe as a rare vagrant on a number of occasions, and has interbred with the Sandwich Tern in France.

This species breeds in very dense colonies on coasts and islands, and exceptionally inland on suitable large freshwater lakes close to the coast. It nests in a ground scrape and lays one to two eggs. Unlike some of the smaller white terns, it is not very aggressive toward potential predators, relying on the sheer density of the nests (often only 20-30cm apart) and nesting close to other more aggressive species such as Heermann's Gulls to avoid predation.

The Elegant Tern feeds by plunge-diving for fish, almost invariably from the sea, 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.

Identification

This is a medium-large tern, with a long, slender orange bill, pale grey upperparts and white underparts. Its legs are black. In winter, the forehead becomes white. Juvenile Elegant Terns have a scalier pale grey back. The call is a characteristic loud grating noise like a Sandwich Tern.

This bird could be confused with the Royal Tern, but the latter species is larger and thicker-billed and shows more white on the forehead in winter. Out of range, it can also be easily confused with the Lesser Crested Tern. Here are some useful point to separate it from other terns in the group:
- It is marginally paler above than the Lesser Crested Tern with a white (not grey) rump.
- It a slightly longer, more slender bill and the curve of the bill is different to Lesser Crested tern.
- The black of the crest the comes down from the crown extends through the eye, creating a small black "smudge" in front of the eye. On Lesser Crested and Royal terns, the black crest stops at the eye.
- The crest is more shaggy than in Lesser Crested Tern

There is a Wikipedia article on seperating Terns in the "Orange-billed Tern" group. http://en.wikipedia.org/wiki/Orange-billed_tern
For a nice discussion on Elegant Tern identification with regards a bird sighted in Ireland, follow this link: http://www.irishbirding.com/kerrytern.html

This species created great excitement when it was discovered at Strandfontien water treatment work in Cape Town, South Africa in January 2006. This was not only the first record for Southern Africa, but also for the African Continent.

For images of this species, you can visit http://www.zestforbirds.co.za/rarities.html

References

Http://www.irishbirding.com/kerrytern.html - Comments on identification of a Tern seen in Ireland.

See also Orange-billed tern.