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.
Fish are first speared and the snake-like neck emerges above the water to toss and swallow the fish head-first
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]
Taxonomyedit
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]
Behaviour and ecologyedit
Prey that has been speared is first brought above the surface.
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]
The feathers of the scapulars and tail have wavy or corrugated webbing.
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]
A darter taking off from water.
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]
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]
Referencesedit
^BirdLife International (2016). "Anhinga melanogaster". IUCN Red List of Threatened Species. 2016: e.T22696712A93582012. doi:10.2305/IUCN.UK.2016-3.RLTS.T22696712A93582012.en. Retrieved 11 November 2021.
^Pennant, T. (1790). "Anhinga melanogaster The Black-bellied Anhinga". Indian Zoology (Second ed.). London: Henry Hughs. p. 53.
^Mayr, E.; Cottrell, G.W. (1979). Check-list of birds of the world. Vol. Volume 1 (Second ed.). Cambridge, Massachusetts: Museum of Comparative Zoology. pp. 180–181.
^Forbes, WA (1882). "On some Points in the Anatomy of the Indian Darter (Plotus melanogaster), and on the Mechanism of the Neck in the Darters (Plotus), in connexion with their Habits". Proceedings of the Zoological Society of London. 50 (1): 208–212. doi:10.1111/j.1096-3642.1882.tb02736.x.
^Beddard, Frank E. (1892). "Notes on the Anatomy and Osteology of the Indian Darter (Plotus melanogaster)". Proceedings of the Zoological Society of London. 60 (2): 291–296. doi:10.1111/j.1469-7998.1892.tb06831.x.
^ abSchodde, R; Guy M. Kirway; Richard Porter (2012). "Morphological differentiation and speciation among darters (Anhinga)". Bulletin of the British Ornithologists' Club. 132 (4): 283–294.
^Rasmussen, PC & JC Anderton (2005). Birds of South Asia. The Ripley Guide. Volume 2. Washington DC and Barcelona: Smithsonian Institution and Lynx Edicions. p. 53.
^Sharpe, RB & W R Ogilvie-Grant (1898). Catalogue of the birds in the British Museum. Volume 26. London: British Museum. pp. 414–417.
^Whistler, Hugh (1949). Popular handbook of Indian birds (4th ed.). London: Gurney and Jackson. pp. 493–495.
^Blanford, WT (1898). The Fauna of British India, Including Ceylon and Burma. Birds. Volume 4. London: Taylor and Francis. pp. 344–345.
^Sinclair, WF (1899). "Plumage of the Snake-bird Plotus melanogaster". J. Bombay Nat. Hist. Soc. 12 (4): 784.
^Baker, ECS (1929). The Fauna of British India, Including Ceylon and Burma. Birds. Volume 6 (2nd ed.). London: Taylor and Francis. pp. 282–283.
^Harrison, CJO (1978). "Osteological differences in the leg bones of two forms of Anhinga" (PDF). Emu. 78 (4): 230–231. doi:10.1071/MU9780230.
^ abcdefgAli, Salim; Ripley, S.D. (1978). Handbook of the birds of India and Pakistan. Volume 1 (2nd ed.). Oxford University Press. pp. 43–46.
^Pathak, B. J.; Vijayan, S. & Pati, B. P. (2004). "Observations on chick mortality in Darter Anhinga melanogaster in Gir forest". J. Bombay Nat. Hist. Soc. 101 (2): 310.
^Neginhal, SG (1982). "The birds of Ranganathittu". J. Bombay Nat. Hist. Soc. 79 (3): 581–593.
^Abdulali, Humayun (1948). "Peculiar behaviour of the Darter (Anhinga melanogaster Pennant)". J. Bombay Nat. Hist. Soc. 47 (3): 549.
^Bates, R.S.P. (1949). "Peculiar behaviour of the Darter (Anhinga melanogaster Pennant)". J. Bombay Nat. Hist. Soc. 48 (4): 810–811.
^"Keswal (1886). "Notes on the waters of Western India. Part 1-British Deccan and Khadesh". J. Bombay Nat. Hist. Soc. 1: 97–123.
^Gupta, Ramesh (1964). "Schwartzitrema anhingi sp. nov. from the Iodian Darter, Anhinga melanogaster Pennant, with a remark on the taxonomic position of the genus Schwartzitrema (Vigueras, 1940) Vigueras, 1941 (Trematoda:Strigeidae)" (PDF). Rev. Biol Trop. 12 (1): 75–79.
^Pande, B. P. (1939). "Two new species of trematodes from Anhinga melanogaster, the Indian darter or snake-bird". Proceedings of the National Academy of Sciences, India. 9: 22–28.
^Gupta, PD (1979). "Trematode fauna of Rajasthan, India. Part 2. Families Cathaemasiidae, Echinostomatidae and Paramphistomidae". Records of the Zoological Survey of India. 75: 203–208.
^Siddiqi, AH (1962). "On Echinorhynchotaenia tritesticulata Fuhrmann, 1909 (Cestoda: Dilepididae), with remarks on its relationship". Parasitology Research. 21 (3): 207–211. doi:10.1007/BF00260232. PMID 13912530. S2CID 3221945.
^Stonor, CR (1948). "Fishing with the Indian Darter (Anhinga melanogaster) in Assam". J. Bombay Nat. Hist. Soc. 47 (4): 746–747.
External linksedit
Wikispecies has information related to Anhinga melanogaster.
Wikimedia Commons has media related to Anhinga melanogaster.
Sounds
Images and videos on the Internet Bird Collection
Darter - Species text in The Atlas of Southern African Birds.
February 15, 2024
oriental, darter, anhinga, melanogaster, water, bird, tropical, south, asia, southeast, asia, long, slender, neck, with, straight, pointed, bill, like, cormorant, hunts, fish, while, body, submerged, water, spears, fish, underwater, bringing, above, surface, t. 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 Oriental darterSunning on a perchConservation statusNear Threatened IUCN 3 1 1 Scientific classificationDomain EukaryotaKingdom AnimaliaPhylum ChordataClass AvesOrder SuliformesFamily AnhingidaeGenus AnhingaSpecies A melanogasterBinomial nameAnhinga melanogasterPennant 1769 2 3 Distribution mapSynonymsPlotus melanogaster Contents 1 Description 2 Taxonomy 3 Behaviour and ecology 4 References 5 External linksDescription edit nbsp Fish are first speared and the snake like neck emerges above the water to toss and swallow the fish head firstThe 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 Taxonomy editThe 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 Behaviour and ecology edit nbsp Prey that has been speared is first brought above the surface 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 nbsp The feathers of the scapulars and tail have wavy or corrugated webbing 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 nbsp A darter taking off from water 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 MeasurementsIndia 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 References edit BirdLife International 2016 Anhinga melanogaster IUCN Red List of Threatened Species 2016 e T22696712A93582012 doi 10 2305 IUCN UK 2016 3 RLTS T22696712A93582012 en Retrieved 11 November 2021 Pennant T 1790 Anhinga melanogaster The Black bellied Anhinga Indian Zoology Second ed London Henry Hughs p 53 Mayr E Cottrell G W 1979 Check list of birds of the world Vol Volume 1 Second ed Cambridge Massachusetts Museum of Comparative Zoology pp 180 181 Forbes WA 1882 On some Points in the Anatomy of the Indian Darter Plotus melanogaster and on the Mechanism of the Neck in the Darters Plotus in connexion with their Habits Proceedings of the Zoological Society of London 50 1 208 212 doi 10 1111 j 1096 3642 1882 tb02736 x Beddard Frank E 1892 Notes on the Anatomy and Osteology of the Indian Darter Plotus melanogaster Proceedings of the Zoological Society of London 60 2 291 296 doi 10 1111 j 1469 7998 1892 tb06831 x a b Schodde R Guy M Kirway Richard Porter 2012 Morphological differentiation and speciation among darters Anhinga Bulletin of the British Ornithologists Club 132 4 283 294 Rasmussen PC amp JC Anderton 2005 Birds of South Asia The Ripley Guide Volume 2 Washington DC and Barcelona Smithsonian Institution and Lynx Edicions p 53 Sharpe RB amp W R Ogilvie Grant 1898 Catalogue of the birds in the British Museum Volume 26 London British Museum pp 414 417 Whistler Hugh 1949 Popular handbook of Indian birds 4th ed London Gurney and Jackson pp 493 495 Blanford WT 1898 The Fauna of British India Including Ceylon and Burma Birds Volume 4 London Taylor and Francis pp 344 345 Sinclair WF 1899 Plumage of the Snake bird Plotus melanogaster J Bombay Nat Hist Soc 12 4 784 Baker ECS 1929 The Fauna of British India Including Ceylon and Burma Birds Volume 6 2nd ed London Taylor and Francis pp 282 283 Harrison CJO 1978 Osteological differences in the leg bones of two forms of Anhinga PDF Emu 78 4 230 231 doi 10 1071 MU9780230 a b c d e f g Ali Salim Ripley S D 1978 Handbook of the birds of India and Pakistan Volume 1 2nd ed Oxford University Press pp 43 46 Pathak B J Vijayan S amp Pati B P 2004 Observations on chick mortality in Darter Anhinga melanogaster in Gir forest J Bombay Nat Hist Soc 101 2 310 Neginhal SG 1982 The birds of Ranganathittu J Bombay Nat Hist Soc 79 3 581 593 Abdulali Humayun 1948 Peculiar behaviour of the Darter Anhinga melanogaster Pennant J Bombay Nat Hist Soc 47 3 549 Bates R S P 1949 Peculiar behaviour of the Darter Anhinga melanogaster Pennant J Bombay Nat Hist Soc 48 4 810 811 Neelakantan KK 1976 Where do Darters sleep Newsletter for Birdwatchers 16 6 9 Keswal 1886 Notes on the waters of Western India Part 1 British Deccan and Khadesh J Bombay Nat Hist Soc 1 97 123 Gupta Ramesh 1964 Schwartzitrema anhingi sp nov from the Iodian Darter Anhinga melanogaster Pennant with a remark on the taxonomic position of the genus Schwartzitrema Vigueras 1940 Vigueras 1941 Trematoda Strigeidae PDF Rev Biol Trop 12 1 75 79 Pande B P 1939 Two new species of trematodes from Anhinga melanogaster the Indian darter or snake bird Proceedings of the National Academy of Sciences India 9 22 28 Gupta PD 1979 Trematode fauna of Rajasthan India Part 2 Families Cathaemasiidae Echinostomatidae and Paramphistomidae Records of the Zoological Survey of India 75 203 208 Siddiqi AH 1962 On Echinorhynchotaenia tritesticulata Fuhrmann 1909 Cestoda Dilepididae with remarks on its relationship Parasitology Research 21 3 207 211 doi 10 1007 BF00260232 PMID 13912530 S2CID 3221945 Stonor CR 1948 Fishing with the Indian Darter Anhinga melanogaster in Assam J Bombay Nat Hist Soc 47 4 746 747 External links edit nbsp Wikispecies has information related to Anhinga melanogaster nbsp Wikimedia Commons has media related to Anhinga melanogaster Sounds Images and videos on the Internet Bird Collection Darter Species text in The Atlas of Southern African Birds Retrieved from https en wikipedia org w index php title Oriental darter amp oldid 1169772719, wikipedia, wiki, book, books, library,
