- Lesser Crested Tern
name = Lesser Crested Tern
status = LC| status= LC | status_system = IUCN3.1
status_ref = [IUCN2006|assessors=
BirdLife International|year=2004|id=49254|title=Sterna bengalensis|downloaded=11 May 2006 Database entry includes justification for why this species is of least concern]
phylum = Chordata
genus = "
species = "T. bengalensis"
binomial = "Thalasseus bengalensis"
binomial_authority = (Lesson,
synonyms = "Sterna bengalensis" Lesson, 1831
The Lesser Crested Tern ("Thalasseus bengalensis", syn. "Sterna bengalensis" - see Bridge "et al.", 2005) is a
seabirdof the ternfamily Sternidae.
It breeds in subtropical coastal parts of the world mainly from the
Red Seaacross the Indian Oceanto the western Pacific, and Australia, with a significant population on the southern coast of the Mediterraneanon islands off the Libyan coast. The Australian birds are probably sedentary, but other populations are migratory, wintering south to South Africa.
birdhas a number of geographical subspecies, differing mainly in size and minor plumage details:
*"T. b. emigrata": breeding in the
Mediterraneanon islands off the coast of Libya, wintering West Africa. Pale grey above (only marginally darker than Sandwich Tern); slightly larger.
*"T. b. bengalensis": northern
Indian Ocean, wintering to South Africa. Medium-dark grey above; slightly smaller.
*"T. b. torresii":
Indonesiasouth to Queensland, Australia, wintering in the same area (birds breeding in the Persian Gulfare also often given as this race). Dark grey above; slightly larger.
The Mediterranean race is a rare vagrant to
Europe, and has bred in pure or mixed pairs (with Sandwich Tern) in Italy, Spainand England.
This species breeds in dense colonies on coasts and islands. It nests in a ground scrape and lays one to two (rarely three) eggs. Nesting behaviour is very similar to that of
Sandwich Terns, with predator avoidance by nesting in very dense colonies, and also (in race "emigrata" at least) by nesting in the late summer when predatory Yellow-legged Gulls have finished breeding and departed from the nesting area.
Like all "Thalasseus" terns, Lesser Crested 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 medium-large tern, very similar in size and general appearance to its three very close relatives Sandwich Tern, Elegant Ternand Chinese Crested Tern. The summer adult has a black cap, black legs and a long sharp orange bill. The upperwings, rump and central tail feathers are grey and the underparts white. The primary flight feathers darken during the summer. In winter, the forehead becomes white. The call is a loud grating noise like Sandwich Tern.
The grey rump is a useful flight identification feature distinguishing it from the related species. The Elegant Tern also differs in a slightly longer, slenderer bill, while Chinese Crested Tern differs in a black tip to the bill and Sandwich Tern a black bill with a yellow tip.
Juvenile Lesser Crested Terns resemble same-age Sandwich Terns, but with a yellow-orange bill, and paler overall, with only faint dark crescents on the mantle feathers.
There are two other orange-billed terns within the range of this species,
Royal Ternand Greater Crested Tern. Both are much larger and stouter-billed; Royal also has a white rump and tail, while Crested (which shares the grey rump) is darker overall above and has a yellower bill. See also Orange-billed tern.
"T. bengalensis" is one of the species to which the "Agreement on the Conservation of African-Eurasian Migratory Waterbirds" (
* Bridge, E. S.; Jones, A. W. & Baker, A. J. (2005): A phylogenetic framework for the terns (Sternini) inferred from mtDNA sequences: implications for taxonomy and plumage evolution. "Molecular Phylogenetics and Evolution" 35: 459–469. [http://www2.hawaii.edu/~khayes/Journal_Club/summer2006/Bridge_et_al_2005_MPE.pdf PDF fulltext]
* del Hoyo, J.; Elliott, A. & Sargatal, J. (editors) (1996): "Handbook of birds of the world, Volume 3: Hoatzin to Auks". Lynx Edicions, Barcelona. ISBN 84-87334-22-9
* Meininger, Peter L., Pim A. Wolf, Dan A. Hadoud and Mohamed F. A. Essghaier (1994) Rediscovery of Lesser Crested Tern breeding in Libya "British Birds" 87(4):160-170
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