Black-bellied tern

Last updated

Black-bellied tern
Black Bellied Tern.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Charadriiformes
Family: Laridae
Genus: Sterna
Species:
S. acuticauda
Binomial name
Sterna acuticauda
Gray, JE, 1831

The black-bellied tern (Sterna acuticauda) is a tern found near large rivers in the Indian subcontinent, its range extending from Pakistan, Nepal and India to Myanmar. It has become very scarce in the eastern part of its range and the International Union for Conservation of Nature has assessed its conservation status as being endangered.

Contents

They have a black belly in the summer and a deep forked tail. They can sometimes resemble whiskered terns (Chlidonias hybrida), but the deeper fork of the tail and the black on the lower belly distinguish them from the shallow fork and black closer to the breast on the whiskered tern. Considering that sequence analysis supports moving the similar black-fronted tern ("Sterna" albostriata) into Chlidonias, this species might also be better placed in that genus, but no research has yet been conducted. [2]

Description

The black-bellied tern grows to a length of 32 to 35 cm (13 to 14 in). In the breeding plumage, the crown and nape are black and the upper parts are pale grey. The throat is white and the breast pale grey, gradually darkening to a black belly. The wings are long, slender and pointed and the tail is deeply forked with sharply pointed tips. The bill and feet are yellow or orange and the iris is reddish brown. [3] [4] Outside the breeding season, the belly is whitish, the tail is reduced in length and the bill has a dark tip. [1]

Distribution and habitat

The species occurs mostly in Pakistan, Nepal, India and Bangladesh, with a separate range in Myanmar. Its typical habitat is lowland rivers and marshes, and sometimes ditches and pools, at altitudes of up to about 730 m (2,400 ft). It is an entirely inland species and is not found on the coast. [1]

Ecology

The black-bellied tern has long wings but its flight is slow, with much flapping. [3] It feeds on insects and small fish, skimming over the surface of the water and ground to pick up insects, and plunging obliquely into the water to feed on crustaceans, tadpoles and fish. [4] Breeding takes place from February to April, the nesting site usually being a flat sandy location near a river or lake, a sand spit or a sandy island. It does not nest colonially but may nest with other birds such as river terns (Sterna aurantia), pratincoles (Glareola spp.) and Indian skimmers (Rynchops albicollis). [4]

Status

S. acuticauda is classified as being endangered by the International Union for Conservation of Nature. [1] The rationale behind this is that the riverine habitats in which it breeds are under threat in much of southeastern Asia and, although it has an extensive range, it is believed to be extinct in southern China, Nepal, Thailand, Laos, Cambodia and Vietnam. Only in Pakistan, India and Bangladesh are there larger populations, and even in these countries, this bird is thought to be seriously declining, and there may be fewer than one thousand mature individuals in existence. [1] The threats it faces include the degradation of the islands and sandspits on which it breeds, the collection of eggs for food, predation of eggs and chicks by dogs, cats and crows, flooding of nesting sites by the construction of river dams, competition for fish by local fishermen, entanglement in nets, disturbance, extraction of water, sand and gravel dredging and pollution. [1]

Related Research Articles

<span class="mw-page-title-main">Tern</span> Family of seabirds

Terns are seabirds in the family Laridae that have a worldwide distribution and are normally found near the sea, rivers, or wetlands. Terns are treated as a subgroup of the family Laridae which includes gulls and skimmers and consists of eleven genera. 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 Inca tern, and some noddies have dark 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.

<span class="mw-page-title-main">Arctic tern</span> Bird that breeds in the Arctic and sub-Arctic and migrates to the Antarctic

The Arctic tern is a tern in the family Laridae. This bird has a circumpolar breeding distribution covering the Arctic and sub-Arctic regions of Europe, Asia, and North America. The species is strongly migratory, seeing two summers each year as it migrates along a convoluted route from its northern breeding grounds to the Antarctic coast for the southern summer and back again about six months later. Recent studies have shown average annual round-trip lengths of about 70,900 km (44,100 mi) for birds nesting in Iceland and Greenland and about 48,700 km (30,300 mi) for birds nesting in the Netherlands. These are by far the longest migrations known in the animal kingdom. The Arctic tern nests once every one to three years.

<span class="mw-page-title-main">Common tern</span> Migratory seabird in the family Laridae with circumpolar distribution

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.

<span class="mw-page-title-main">Little tern</span> Species of bird

The little tern is a seabird of the family Laridae. It was formerly placed into the genus Sterna, which now is restricted to the large white terns. The genus name is a diminutive of Sterna, 'tern'. The specific albifrons is from Latin albus, 'white', and frons, 'forehead'. The former North American and Red Sea S. a. saundersi subspecies are now considered to be separate species, the least tern and Saunders's tern.

<span class="mw-page-title-main">Black tern</span> Species of bird

The black tern is a small tern generally found in or near inland water in Europe, Western Asia and North America. As its name suggests, it has predominantly dark plumage. In some lights it can appear blue in the breeding season, hence the old English name "blue darr". The genus name is from Ancient Greek khelidonios, "swallow-like", from khelidon, "swallow": another old English name for the black tern is "carr swallow". The species name is from Latin niger "shining black".

<span class="mw-page-title-main">White-winged tern</span> Species of bird

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".

<span class="mw-page-title-main">Sandwich tern</span> Species of bird

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 the lesser crested. It breeds in the Palearctic from Europe to the Caspian Sea and winters in South Africa, India, and Sri Lanka.

<span class="mw-page-title-main">Roseate tern</span> Bird in the family Laridae

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.

<span class="mw-page-title-main">Whiskered tern</span> Species of bird

The whiskered tern is a tern in the family Laridae. The genus name is from Ancient Greek khelidonios, "swallow-like", from khelidon, "swallow". The specific hybridus is Latin for hybrid; Peter Simon Pallas thought it might be a hybrid of white-winged black tern and common tern, writing "Sterna fissipes [Chlidonias leucopterus] et Hirundine [Sterna hirundo] natam".

<span class="mw-page-title-main">Lesser crested tern</span> Species of bird

The lesser crested tern is a tern in the family Laridae.

<span class="mw-page-title-main">Forster's tern</span> Species of bird

Forster's tern is a tern in the family Laridae. The genus name Sterna is derived from Old English "stearn", "tern", and forsteri commemorates the naturalist Johann Reinhold Forster.

<span class="mw-page-title-main">Aleutian tern</span> Species of bird

The Aleutian tern is a migratory bird living in the subarctic region of the globe most of the year. It is frequently associated with the Arctic tern, which it closely resembles. While both species have a black cap, the Aleutian tern may be distinguished by its white forehead. During breeding season, the Arctic terns have bright red bills, feet, and legs while those of the Aleutian terns are black.

<span class="mw-page-title-main">Greater crested tern</span> Seabird in the family Laridae

The greater crested tern, also called crested tern or swift 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.

<span class="mw-page-title-main">White-fronted tern</span> Species of bird

The white-fronted tern, also known as tara, sea swallow, black-billed tern, kahawai bird, southern tern, or swallow tail, was first described by Johann Friedrich Gmelin in 1789. A medium-sized tern with an all-white body including underwing and forked tail, with grey hues on the over the upper side of the wing. In breeding adults a striking black cap covers the head from forehead to nape, leaving a small white strip above the black bill.

<span class="mw-page-title-main">Marsh tern</span> Genus of birds

The name marsh tern refers to terns of the genus Chlidonias, which are typically found in freshwater marshes, rather than coastal locations. The genus name Chlidonias is from Ancient Greek khelidonios, "swallow-like", from khelidon, "swallow".

<span class="mw-page-title-main">River tern</span> Species of bird

The Indian river tern or just river tern is a tern in the family Laridae. It is a resident breeder along inland rivers from Iran east into the Indian Subcontinent and further to Myanmar to Thailand, where it is uncommon. Unlike most Sterna terns, it is almost exclusively found on freshwater, rarely venturing even to tidal creeks.

<span class="mw-page-title-main">Antarctic tern</span> Species of bird

The Antarctic tern is a seabird in the family Laridae. It ranges throughout the southern oceans and is found on small islands around Antarctica as well as on the shores of the mainland. Its diet consists primarily of small fish and crustaceans. It is very similar in appearance to the closely related Arctic tern, but it is stockier, and it is in its breeding plumage in the southern summer, when the Arctic tern has shed old feathers to get its non-breeding plumage. The Antarctic tern does not migrate like the Arctic tern does, but it can still be found on a very large range. This tern species is actually more closely related to the South American tern.

<span class="mw-page-title-main">Black-fronted tern</span> Species of bird

The black-fronted tern, also known as sea martin, ploughboy, inland tern, riverbed tern or tarapiroe, is a small tern generally found in or near bodies of fresh water in New Zealand, where it forages for freshwater fish, arthropods and worms. It has a predominantly grey plumage. Restricted to breeding in the eastern regions of the South Island, it is declining and threatened by introduced mammals and birds. It is rated as endangered on the International Union for Conservation of Nature (IUCN)'s Red List of Threatened Species.

<span class="mw-page-title-main">South American tern</span> Species of bird

The South American tern is a species of tern found in coastal regions of southern South America, including the Falkland Islands, ranging north to Peru and Brazil. It is generally the most common tern in its range. The smaller, highly migratory common tern closely resembles it. The specific epithet refers to the "swallow-like" forked tail feathering.

<span class="mw-page-title-main">Snowy-crowned tern</span> Species of bird

The snowy-crowned tern, also known as Trudeau's tern, is a species of bird in subfamily Sterninae of the family Laridae, the gulls, terns, and skimmers. It is native to Argentina, Brazil, Chile, Uruguay, and possibly Paraguay, and also vagrant in Peru and the Falkland Islands.

References

  1. 1 2 3 4 5 6 BirdLife International (2017). "Sterna acuticauda". IUCN Red List of Threatened Species . 2017: e.T22694711A110488626. doi: 10.2305/IUCN.UK.2017-1.RLTS.T22694711A110488626.en . Retrieved 19 November 2021.
  2. 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 (2): 459–469. doi:10.1016/j.ympev.2004.12.010. PMID   15804415.
  3. 1 2 Journal of the Asiatic Society of Bengal. Asiatic Society of Bengal. 1834. p. 649.
  4. 1 2 3 Gochfeld, M.; Burger, J.; de Juana, E. (2015). "Black-bellied Tern (Sterna acuticauda)". Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. Retrieved 16 December 2015.