Oriental darter | |
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Sunning on a perch | |
Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Suliformes |
Family: | Anhingidae |
Genus: | Anhinga |
Species: | A. melanogaster |
Binomial name | |
Anhinga melanogaster | |
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Distribution map | |
Synonyms | |
Plotus melanogaster |
The Oriental darter (Anhinga melanogaster) is a water bird of tropical South Asia and Southeast Asia. It has a long and slender neck with a straight, pointed bill and, like the cormorant, it hunts for fish while its body is submerged in water. It spears a fish underwater, bringing it above the surface, tossing and juggling it before swallowing the fish head first. The body remains submerged as it swims, and the slender neck alone is visible above the water, which accounts for the colloquial name of snakebird. Like the cormorants, it has wettable feathers and it is often found perched on a rock or branch with its wings held open to dry.
The Oriental darter is like all other anhingas, a cormorant-like species that has a very long neck. The structure of the neck is as in other species of darter with strongly developed muscles about a kink in the neck at the 8th and 9th vertebrae that allows it to be flexed and darted forward with rapid force to stab fish underwater. The edges of the commissures of the mandible tips have minute inward pointing serrations that hold impaled fish. [4] [5]
The adult plumage above is black and the wing coverts and tertials having silvery streaks along the shaft. The crown and neck are brown shading to black towards the back of the neck. The underparts are blackish brown. A pale line over the eye and throat and a line running along the sides of the neck gives it a striped appearance. The iris is white with a yellow ring (brighter yellow in breeding birds) around it. The tip of the upper mandible is dark while the base is pale brown bill while the lower mandible is yellowish. The legs and webbing on the foot are yellow in immatures and non-breeding birds while breeding birds have darker grey tarsi and toes with yellow webbing. [6] The sexes are not easily distinguishable but males tend to have black speckles that coalesce on the white throat. [7] Adult females have a shorter bill and tend to have the black at the base of neck and chest separated from the hind neck by a wide buff band that ends at the shoulder. This pattern however is also found in immatures whose neck is lighter and lack the long pointed scapulars. [8] In flight the long and slender neck, wide wing and wedge shaped tail make it distinctive. [9] [10] Young birds have a pale brown neck and appear whitish on the underside and lack the white streak along the side of the neck. The inner secondaries or tertials and the central tail feathers appear wavy or corrugated. [11] The tail is long and made up of twelve stiff feathers which are dragged along the ground when the bird attempts to walk or hop on land. [12]
The Oriental darter is a member of the darter family, Anhingidae, and is closely related to American (Anhinga anhinga), African (Anhinga rufa, with vulsini of Madagascar as a subspecies), and Australasian (Anhinga novaehollandiae) darters. These were for sometime treated as subspecies of Anhinga melanogaster. [13] The Oriental darter differs in appearance from American darters most recognisably by its white lateral neck stripe. [6]
The Oriental darter is found mainly in freshwater lakes and streams. They usually forage singly, with the entire body submerged, swimming slowly forward using their webbed feet while the head and neck is moved jerkily above the water. It darts its neck to impale fish and then brings them out of water, tossing them into the air before swallowing the fish head first. They may sometimes be found along with cormorants which share the habit of spreading out their wings to dry when perched on a waterside rock or tree. They sometimes soar on thermals during the warm part of the day but will alternate flapping and gliding in normal flight. [14]
They nest in mixed species heronries where they build a stick platform on the nest tree which is usually surrounded by water. Several pairs may nest close to each other. [15] The branch is flattened by the birds prior to the placement of the sticks that form the nest platform. The nest sites are defended from other birds with posturing and thrusts of the neck. The breeding season is June to August (during the rainy season) in northern India, April–May in southwestern India and in winter in southeastern India (during the northeast monsoon). [16] The usual clutch consists of three to six spindle shaped bluish-green eggs with a white chalky covering that gets soiled over time. Both parents incubate the eggs, beginning after the first egg is laid which leads to asynchronous hatching of the young. The newly hatched chicks are bare and covered with some down on the head. As they grow, they become covered in white down. The chicks feed by thrusting their heads down the throat of their parents. [14]
Adults go through a synchronous moult of their flight feathers after the breeding season, resulting in the loss of flying ability for a brief period. When disturbed from their perches during this period, they dive into the water below and attempt to escape underwater. [14] This escape behaviour is also employed by chicks at the nest. [17] [18] They are very silent except at the nest where they produce grunts and croaks and a disyllabic chigi-chigi-chigi. Chicks are noisy when begging for food. [14] Adults roost communally in trees close to or over water. [19]
Chicks, especially those more than half grown are sometimes preyed on by raptors such as Pallas's fish eagle (Haliaetus leucoryphus). [14] The long scapular feathers were once popular for use in decorating hats. [20] A number of parasites have been recorded from adult birds including Schwartzitrema anhingi (Trematoda), [21] Petasiger nicolli, [22] Mesorchis pendulus, [23] and Echinorhynchotaenia tritesticulata (Cestoda:Dilepididae). [24]
Measurements | |||
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India [14] | |||
Culmen | 74–90 mm (2.9–3.5 in) | ||
Wing | 331–357 mm (13.0–14.1 in) | ||
Tail | 202–240 mm (8.0–9.4 in) | ||
Tarsus | 42–47 mm (1.7–1.9 in) | ||
Weight | 1,160–1,500 g (40.9–52.9 oz) |
In some parts of northeastern India, darters were (or are) used by tribals to capture fish from streams. [14] A ring is tied around the neck to prevent them from swallowing the prey just as is done with cormorant fishing in parts of Southeast Asia. [25]
The darters, anhingas, or snakebirds are mainly tropical waterbirds in the family Anhingidae, which contains a single genus, Anhinga. There are four living species, three of which are very common and widespread while the fourth is rarer and classified as near-threatened by the IUCN. The term snakebird is usually used without any additions to signify whichever of the completely allopatric species occurs in any one region. It refers to their long thin neck, which has a snake-like appearance when they swim with their bodies submerged, or when mated pairs twist it during their bonding displays. "Darter" is used with a geographical term when referring to particular species. It alludes to their manner of procuring food, as they impale fishes with their thin, pointed beak. The American darter is more commonly known as the anhinga. It is sometimes called "water turkey" in the southern United States; though the anhinga is quite unrelated to the wild turkey, they are both large, blackish birds with long tails that are sometimes hunted for food.
The Indian spot-billed duck is a species of large dabbling duck that is a non-migratory breeding duck throughout freshwater wetlands in the Indian subcontinent. The name is derived from the red spot at the base of the bill that is found in the mainland Indian population. When in water it can be recognized from a long distance by the white tertials that form a stripe on the side, and in flight it is distinguished by the green speculum with a broad white band at the base. This species and the eastern spot-billed duck were formerly considered conspecific, together called the spot-billed duck.
The lesser whistling duck, also known as Indian whistling duck or lesser whistling teal, is a species of whistling duck that breeds in the Indian subcontinent and Southeast Asia. They are nocturnal feeders that during the day may be found in flocks around lakes and wet paddy fields. They can perch on trees and sometimes build their nest in the hollow of a tree. This brown and long-necked duck has broad wings that are visible in flight and produces a loud two-note wheezy call. It has a chestnut rump, differentiating it from its larger relative, the fulvous whistling duck, which has a creamy white rump.
The western reef heron, also called the western reef egret, is a medium-sized heron found in southern Europe, Africa and parts of Asia. It has a mainly coastal distribution and occurs in several plumage forms: a slaty-grey plumage in which it can only be confused with the rather uncommon dark morph of the Little egret ; a white form which can look very similar to the little egret although the bill tends to be paler and larger and the black form with white throat E. g. gularis of West Africa. There are also differences in size, structure and foraging behaviour. There have been suggestions that the species hybridizes with the Little Egret, and based on this, some authors treat schistacea and gularis as subspecies of Egretta garzetta. Works that consider the Western Reef Heron as a valid species include the nominate gularis and schistacea as subspecies.
The pheasant-tailed jacana is a jacana in the monotypic genus Hydrophasianus. Like all other jacanas, they have elongated toes and nails that enable them to walk on floating vegetation in shallow lakes, their preferred habitat. They may also swim or wade in water reaching their body while foraging mainly for invertebrate prey. They are found in tropical Asia from Yemen in the west to the Philippines in the east and move seasonally in parts of their range. They are the only jacanas that migrate long distances and have different non-breeding and breeding plumages. The pheasant-tailed jacana forages by swimming or by walking on aquatic vegetation. Females are larger than males and are polyandrous, laying several clutches that are raised by different males in their harem.
The black-necked stork is a tall long-necked wading bird in the stork family. It is a resident species across the Indian Subcontinent and Southeast Asia with a disjunct population in Australia. It lives in wetland habitats and near fields of certain crops such as rice and wheat where it forages for a wide range of animal prey. Adult birds of both sexes have a heavy bill and are patterned in white and irridescent blacks, but the sexes differ in the colour of the iris with females sporting yellow irises and males having dark-coloured irises. In Australia, it is known as a jabiru although that name refers to a stork species found in the Americas. It is one of the few storks that are strongly territorial when feeding and breeding.
The common tailorbird is a songbird found across tropical Asia. Popular for its nest made of leaves "sewn" together and immortalized by Rudyard Kipling as Darzee in his Jungle Book, it is a common resident in urban gardens. Although shy birds that are usually hidden within vegetation, their loud calls are familiar and give away their presence. They are distinctive in having a long upright tail, greenish upper body plumage and rust coloured forehead and crown. This passerine bird is typically found in open farmland, scrub, forest edges and gardens. Tailorbirds get their name from the way their nest is constructed. The edges of a large leaf are pierced and sewn together with plant fibre or spider silk to make a cradle in which the actual nest is built. Punjab tailor birds produce shiny red eggs, but became extinct around 1975 due to laying their eggs in fields used to grow fodder crops.
The spot-billed pelican or gray pelican is a member of the pelican family. It breeds in southern Asia from southern Iran across India east to Indonesia. It is a bird of large inland and coastal waters, especially large lakes. At a distance they are difficult to differentiate from other pelicans in the region although it is smaller but at close range the spots on the upper mandible, the lack of bright colours and the greyer plumage are distinctive. In some areas these birds nest in large colonies close to human habitations.
The Indian cormorant or Indian shag is a member of the cormorant family. It is found mainly along the inland waters of the Indian Subcontinent but extends west to Sind and east to Thailand and Cambodia. It is a gregarious species that can be easily distinguished from the similar sized little cormorant by its blue eyes, small head with a sloping forehead and a long narrow bill ending in a hooked tip.
The little cormorant is a member of the cormorant family of seabirds. Slightly smaller than the Indian cormorant it lacks a peaked head and has a shorter beak. It is widely distributed across the Indian Subcontinent and extends east to Java, where it is sometimes called the Javanese cormorant. It forages singly or sometimes in loose groups in lowland freshwater bodies, including small ponds, large lakes, streams and sometimes coastal estuaries. Like other cormorants, it is often found perched on a waterside rock with its wings spread out after coming out of the water. The entire body is black in the breeding season but the plumage is brownish, and the throat has a small whitish patch in the non-breeding season. These birds breed gregariously in trees, often joining other waterbirds at heronries.
The painted stork is a large wader in the stork family. It is found in the wetlands of the plains of tropical Asia south of the Himalayas in the Indian Subcontinent and extending into Southeast Asia. Their distinctive pink tertial feathers of the adults give them their name. They forage in flocks in shallow waters along rivers or lakes. They immerse their half open beaks in water and sweep them from side to side and snap up their prey of small fish that are sensed by touch. As they wade along they also stir the water with their feet to flush hiding fish. They nest colonially in trees, often along with other waterbirds. The only sounds they produce are weak moans or bill clattering at the nest. They are not migratory and only make short-distance movements in some parts of their range in response to changes in weather or food availability or for breeding. Like other storks, they are often seen soaring on thermals.
The Asian openbill or Asian openbill stork is a large wading bird in the stork family Ciconiidae. This distinctive stork is found mainly in the Indian subcontinent and Southeast Asia. It is greyish or white with glossy black wings and tail and the adults have a gap between the arched upper mandible and recurved lower mandible. Young birds are born without this gap which is thought to be an adaptation that aids in the handling of snails, their main prey. Although resident within their range, they make long distance movements in response to weather and food availability.
The purple sunbird is a small bird in the sunbird family found mainly in South and Southeast Asia but extending west into parts of the Arabian peninsula. Like other sunbirds they feed mainly on nectar, although they will also take insects, especially when feeding young. They have a fast and direct flight and can take nectar by hovering like a hummingbird but often perch at the base of flowers. The males can appear all black in harsh sunlight but the purple iridescence is visible on closer observation or under good light conditions. Females are olive above and yellowish below.
The African darter (Anhinga rufa), sometimes called the snakebird, is a water bird of sub-Saharan Africa and Iraq.
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The blue-winged parakeet, also known as the Malabar parakeet is a species of parakeet endemic to the Western Ghats of southern India. Found in small flocks, they fly rapidly in forest clearings while making screeching calls that differ from those of other parakeet species within their distribution range. Their long blue tails tipped in yellow and the dark wings with blue contrast with the dull grey of their head and body. Adult males and females can be easily told apart from the colour of their beak.
The large gray babbler is a member of the family Leiothrichidae found across India and far western Nepal. They are locally common in the scrub, open forest and gardenland. They are usually seen in small groups and are easily distinguished from other babblers in the region by their nasal call and the whitish outer feathers to their long tail. It is one of the largest babblers in the region.
The bank myna is a myna found in the northern parts of South Asia. It is smaller but similar in colouration to the common myna, only differing in having brick-red naked skin behind the eyes instead of yellow. It is greyer on the underside and in this and in the presence of a slight tuft of feathers bears some resemblance to the jungle myna. They are found in flocks on the plains of northern and central India, often within towns and cities. Their range appears to be extending southwards into India. The name is derived from their habit of nesting almost exclusively in the earthen banks of rivers, where they excavate burrows and breed in large colonies.
The Australasian darter or Australian darter is a species of bird in the darter family, Anhingidae. It is found in Australia, Indonesia, and Papua New Guinea. It weighs around 2.6 kg and spans 86–94 cm (34–37 in) in length.
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