Lesser crested tern | |
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A pair of Lesser crested terns Thalasseus bengalensis from Akshi Beach, Maharashtra, India | |
Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Charadriiformes |
Family: | Laridae |
Genus: | Thalasseus |
Species: | T. bengalensis |
Binomial name | |
Thalasseus bengalensis (Lesson, 1831) | |
Synonyms | |
Sterna bengalensisLesson, 1831 |
The lesser crested tern (Thalasseus bengalensis) [2] is a tern in the family Laridae.
The genus name is from Ancient Greek Thalasseus, "fisherman" from thalassa, "sea". The specific bengalensis means "of Bengal", the type locality, historically referring to much of northern India and Bangladesh. [3]
It breeds in subtropical coastal parts of the world mainly from the Red Sea across the Indian Ocean to the western Pacific, and Australia, with a significant population on the southern coast of the Mediterranean on two islands off the Libyan coast. Accidental breeding has also been reported in Italy and France. The Australian birds are probably sedentary, but other populations are migratory, wintering south to South Africa.
This bird has three geographical subspecies, differing mainly in size and minor plumage details: [4] [5]
The Mediterranean subspecies is a rare vagrant to Europe, and has bred in pure or mixed pairs (with Sandwich tern) in Italy, Spain and 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 T. b. emigratus at least) by nesting in the late summer when predatory yellow-legged gulls have finished breeding and departed from the nesting area. [6]
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 tern and 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. [7]
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. [7]
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 tern and 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 (AEWA) applies, and one of 10 marine bird species listed in Mediterranean marine birds Action Plan. [8]
In India the Lesser crested tern is protected in the PM Sayeed Marine Birds Conservation Reserve. [9]
Terns are seabirds in the family Laridae, subfamily Sterninae, that have a worldwide distribution and are normally found near the sea, rivers, or wetlands. Terns are treated in eleven genera in a subgroup of the family Laridae, which also includes several genera of gulls and the skimmers (Rynchops). They are slender, lightly built birds with long, forked tails, narrow wings, long bills, and relatively short legs. Most species are pale grey above and white below with a contrasting black cap to the head, but the marsh terns, the black-bellied tern, the Inca tern, and some noddies have dark body plumage for at least part of the year. The sexes are identical in appearance, but young birds are readily distinguishable from adults. Terns have a non-breeding plumage, which usually involves a white forehead and much-reduced black cap.
The common tern is a seabird in the family Laridae. This bird has a circumpolar distribution, its four subspecies breeding in temperate and subarctic regions of Europe, Asia and North America. It is strongly migratory, wintering in coastal tropical and subtropical regions. Breeding adults have light grey upperparts, white to very light grey underparts, a black cap, orange-red legs, and a narrow pointed bill. Depending on the subspecies, the bill may be mostly red with a black tip or all black. There are several similar species, including the partly sympatric Arctic tern, which can be separated on plumage details, leg and bill colour, or vocalisations.
The white-winged tern, or white-winged black tern, is a species of tern in the family Laridae. It is a small species generally found in or near bodies of fresh water across much of the world, including Europe, Africa, Asia, and Australia. The genus name is from Ancient Greek khelidonios, "swallow-like", from khelidon, "swallow".
The Sandwich tern is a tern in the family Laridae. It is very closely related to the lesser crested tern, Chinese crested tern, Cabot's tern, and elegant tern and has been known to interbreed with both elegant and lesser crested. It breeds in the Palearctic from Europe to the Caspian Sea and winters in South Africa, India, and Sri Lanka.
The roseate tern is a species of tern in the family Laridae. The genus name Sterna is derived from Old English "stearn", "tern", and the specific dougallii refers to Scottish physician and collector Dr Peter McDougall (1777–1814). "Roseate" refers to the bird's pink breast in breeding plumage.
The gull-billed tern, formerly Sterna nilotica, is a tern in the family Laridae. It is widely distributed and breeds in scattered localities in Europe, Asia, northwest Africa, and the Americas. The Australian gull-billed tern was previously considered a subspecies.
The royal tern is a tern in the family Laridae. The species is endemic to the Americas, though vagrants have been identified in Europe.
The elegant tern is a tern in the family Laridae. It breeds on the Pacific coasts of the southern United States and Mexico and winters south to Peru, Ecuador and Chile.
The Chinese crested tern is a tern in the family Laridae. It is the county bird of Lienchiang County, Fuchien.
The greater crested tern, also called crested tern, swift tern, or great crested tern, is a tern in the family Laridae that nests in dense colonies on coastlines and islands in the tropical and subtropical Old World. Its five subspecies breed in the area from South Africa around the Indian Ocean to the central Pacific and Australia, all populations dispersing widely from the breeding range after nesting. This large tern is closely related to the royal and lesser crested terns, but can be distinguished by its size and bill colour.
Orange-billed tern is a name applied to a group of three large terns in the genus Thalasseus with orange bills, which are quite similar in appearance and often considered difficult to identify, namely:
Thalasseus, the crested terns, is a genus of eight species of medium-large to large terns in the family Laridae.
Cabot's tern is a species of bird in subfamily Sterninae of the family Laridae, the gulls, terns, and skimmers. It is found in the eastern U.S. and Middle America, the Caribbean, Trinidad and Tobago, and in every mainland South American country except Bolivia and Paraguay.
The West African crested tern is a bird species in the family Laridae. Until 2020 it was considered a subspecies of the New World royal tern, Thalasseus maximus.