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Difference between revisions of "Elegant Tern" - BirdForum Opus

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'''Call''': a characteristic loud grating noise similar to a [[Sandwich Tern]].
 
'''Call''': a characteristic loud grating noise similar to a [[Sandwich Tern]].
 
==References==
 
==References==
#Dufour, P., et al. (2017). Multilocus barcoding confirms the occurrence of Elegant Terns in Western Europe. ''Journal of Ornithology'' 158 (2): 351–361 ([https://link.springer.com/article/10.1007/s10336-016-1380-0 abstract]).
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#Dufour, P., et al. (2017). Multilocus barcoding confirms the occurrence of Elegant Terns in Western Europe. ''Journal of Ornithology'' 158 (2): 351–361 ([https://link.springer.com/article/10.1007/s10336-016-1380-0 abstract], [http://www.digimages.info/stevoy/Elegant_Terns_Sterna_elegans_Europe.pdf pdf full text]).
 
#{{Ref-Clements6thAug17}}#Avibase
 
#{{Ref-Clements6thAug17}}#Avibase
 
# Howell & Webb, 1995. A guide to the birds of Mexico and northern Central America. Oxford University Press. ISBN 0198540124
 
# Howell & Webb, 1995. A guide to the birds of Mexico and northern Central America. Oxford University Press. ISBN 0198540124

Revision as of 14:23, 16 November 2017

Pair in full breeding plumage
Photo by tehag
Loreto, Baja California Sur, Mexico, April 2009
Thalasseus elegans

Sterna elegans

Identification

Photo by Doug Greenberg
Moss Landing, California, USA, August 2003

Length 39–43 cm (15¼-17 in), wingspan 76–81 cm, weight 200–300 g
Adult a medium-large tern with a shaggy crest

  • Pale grey upperparts
  • White underparts
  • Black legs
  • Long, slender, slightly downcurved orange bill, often with yellow at tip and more so in winter
  • Black crest is very long, reaching the nape in breeding plumage
  • White forehead in winter plumage (August to March)

Juveniles have a scalier pale grey back

Similar Species

Photo by Glen Tepke
Moss Landing, California, USA, August 2003

May be confused with the larger Royal Tern, which has a thicker bill and has more white on the forehead in winter. The bill of Royal Tern is often a darker orange with less yellow, but even more important is the difference in shape, with the Royal Tern's bill being straight, not downcurved. Royal Tern also loses its black forehead earlier in the summer, even as soon as breeding starts in May; in winter plumage, its black crest stops at the eye, whereas in Elegant, the black extends down through to a spot in front of the eye.

Vagrants in Europe can be confused very easily with Lesser Crested Tern, which is slightly darker above and has a grey rump. The bill is slightly shorter and thicker, and the crest is rather neater.

Distribution

The Americas: Breeds mainly in Baja California, Mexico, in the Gulf of Mexico, with a few also on the Pacific coast north to southern California. Post-breeding dispersal regular north to Oregon, with vagrants recorded north to British Columbia, and east to Texas and very rarely as far as Florida; very rare inland, apart from the near-coastal Salton Sea; one record from Tucson, Arizona, in June 2015. Winters off the Pacific coast of South America, mostly from Ecuador to Chile.

Old World: vagrants and even breeding pairs (recently verified by genetic analysis[1]) have been recorded in several western European countries from Britain and Ireland south to Spain; there are several records from France and recent records from Denmark and Britain. Some of these birds have also been seen wintering in South Africa. From the mid-1970s to mid-1980s an Elegant Tern was present each summer in a Sandwich Tern colony on the Banc d'Arguin on the western coast of France and paired with a Sandwich Tern. Another, or the same, individual was present from 1987 to at least 1996. In 1984 there were two mixed pairs and hybrid young have been produced. Recorded for the first time in Denmark in the summer of 2000, and in May 2002 the first for Britain (not yet formally accepted) was a bird at Dawlish Warren in Devon. The latter bird reappeared at the same site in July and later in Gwynedd, Wales.

Taxonomy

This is a monotypic species[2]. The one named subspecies T. e. ichlus is generally considered not to be distinct[3].

Like the other Thalasseus terns, this species was formerly often placed in the genus Sterna. Hybrids with Sandwich Tern have been recorded in western Europe.

Habitat

Breeds in sandy to rocky shores and islands with 95% of the population breeding on the rocky island Isla Rasa in the Gulf of Mexico off Baja California, Mexico. In winter will spend the night on sand or mudflats on the coast. Feeding is in the sea (but near the shore) and in coastal lagoons.

Behaviour

Diet

They feed by plunge-diving for fish. It usually dives directly, and not from the "stepped-hover" favoured by the Arctic Tern.

Breeding

Breeding season from early April to June. Breeds in colonies together with other species of terns and gulls. In courtship display the male offers a fish to the female. Lays one egg. The young grow rapidly and group together after about six days. Parental care continues until November.
Colonies suffer predation by Heermann's Gull, Western Gull and Yellow-footed Gull.

Vocalisation

Call: a characteristic loud grating noise similar to a Sandwich Tern.

References

  1. Dufour, P., et al. (2017). Multilocus barcoding confirms the occurrence of Elegant Terns in Western Europe. Journal of Ornithology 158 (2): 351–361 (abstract, pdf full text).
  2. Clements, J. F., T. S. Schulenberg, M. J. Iliff, D. Roberson, T. A. Fredericks, B. L. Sullivan, and C. L. Wood. 2017. The eBird/Clements checklist of birds of the world: v2017, with updates to August 2017. Downloaded from http://www.birds.cornell.edu/clementschecklist/download/
  3. Avibase
  4. Howell & Webb, 1995. A guide to the birds of Mexico and northern Central America. Oxford University Press. ISBN 0198540124
  5. Restall et al. 2006. Birds of Northern South America. Yale University Press. ISBN 9780300124156
  6. Alvaro Jaramillo. 2003. Birds of Chile. Princeton Field Guides. ISBN 0-691-11740-3
  7. Handbook of the Birds of the World Alive (retrieved October 2017)

Recommended Citation

External Links

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