Rose-headed duck
| Rose-headed duck | ||||||||||||
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The rose-headed duck on a panel |
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| Systematics | ||||||||||||
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| Scientific name of the genus | ||||||||||||
| Rhodonessa | ||||||||||||
| Reichenbach , 1853 | ||||||||||||
| Scientific name of the species | ||||||||||||
| Rhodonessa caryophyllacea | ||||||||||||
| ( Latham , 1790) |
The rose- headed duck ( Rhodonessa caryophyllacea ), also known as the carnation duck , is a possibly extinct species of diving duck . According to a study published by Bradley C. Livezey in 1998, phylogenetic studies have shown that the rose-headed duck is closely related to the red-crested pochard ( Netta rufina ). The suggestion was made to place her in the genus Netta . However, this was rejected by other scientists because the rose-headed duck has numerous peculiarities that separate it from other species of duck .
description
The 60 cm long rose-headed duck is almost unmistakable under good observation conditions. The body and neck are relatively long. The wing length is 25 cm. The adult males have a somewhat tufted forelock and a peculiar stiff necked posture. They do not have a splendid dress, but have a chocolate-brown body all year round, which contrasts with a dark pink head and buttocks. The legs are long and reddish black.
The females and fledglings are paler and resemble a dark red-crested pochard with a pink-tinged head. Confusion with the male red-crested pochard comes mainly from observations of swimming birds, the latter species having a conspicuous fox-colored to orange head. The legs of the females are brown. The iris is brown-orange.
Female rose-headed ducks - in flight or viewed from a distance - again resemble the spotted duck ( Anas poecilorhyncha ). The two species can only be distinguished in flight under good observation conditions at the top of the wings. Those of the rose-headed duck have clearly prominent white arm covers and beige-pink colored arm wings. The arm-wings of the spotted duck show a dark green mirror .
There is insufficient data on the moulting process of this species. The small plumage was probably changed twice a year. The male's call is described as a gasping whistle. The sound repertoire also includes a soft, two-syllable call, which is onomatopoeically described as " wugh ". The calls of the female are described as croaking.
Habitat and way of life
The breeding grounds of the Pink-headed duck are in the lowland marshes and ponds in the elephant grass - jungle . The diurnal rose-headed duck prefers to search for food on the surface of the water, but is quite capable of diving short distances. They are gregarious birds that often come in flocks of 30 or more specimens.
The food of the omnivore consists mainly of mussels , small crustaceans and aquatic plants , which they graze upside down like the species of the genus Netta . The breeding season is between April and May. The approximately circular nest, which has a diameter of about two meters, is built in zones with dense grass vegetation on the pond bank. The clutch consists of five to ten spherical eggs, with an approximate diameter of four centimeters.
Reproduction
The rose-headed duck builds its nest at a maximum distance of 500 meters from the nearest body of water. The rounded nest is made of dry grass and some feathers. It measures 23 centimeters in diameter. The nesting trough is between 10 and 12.5 centimeters deep. It is built hidden in the tall grass. The eggs are gray-white. The eggs kept in the British Museum measure 45.9 × 42 millimeters. The full clutch comprises between five and ten eggs. No data are available for the duration of the incubation period. However, both parent birds were observed near the nest, so that it cannot be ruled out that the male may be near the nest during the breeding season. Insufficient data is available on the development of the downy chicks. It is likely that it takes two months for the young rose-headed ducks to fledge. Rose-headed ducks kept in captivity reached an age of more than twelve years.
status
This duck was previously found in eastern India , Bangladesh, and northern Myanmar . They were still numerous in at least the 18th century and mainly settled on the lower course of the Ganges and on the Brahmaputra. Today it may be extinct. The last secure evidence is from 1935. Unconfirmed reports continued into the early 1960s. Rory Nugent, an American bird watcher, and Shankar Barua from New Delhi claim to have spotted the species on the banks of the Brahmaputra in 1988 . The two ornithologists began their search at Saikhoa Ghat at the northeast end of the river on the Indian border side. After 29 days of sailing, Rory Nugent reported seeing the rose-headed duck in a congregation of other waterfowl. Nugent's and Barua's sighting was not enough, however, to remove the rose-headed duck from the list of extinct birds.
For decades there have been unconfirmed sightings of rose-headed ducks from the Mali Hka and Chindwin Myit depressions in northern Myanmar . The area is largely unexplored and searches have so far been unsuccessful. Confusion with the red-bellied and red-billed duck cannot be ruled out in most sightings of the rose-headed duck.
An expedition report from the Hu-Kaung valley in November 2003 (Nguyen, 2003) came to the reasonable assumption that the existence of the rose-headed duck in the Kachin state in Myanmar cannot be ruled out. There are large and almost impenetrable wetlands in Kachin State that provide retreats for a number of rare bird species. Among other things, the Malay duck, which is currently one of the most endangered species of duck, also occurs here. An extensive search operation on the Nat Kaung River between Kamaing and Shadusup in October 2005 was unsuccessful. However, a variety of other ducks, such as the spotted-billed duck and the sun duck ( Cairina scutulata ), could be observed.
The reason the rose-headed duck became extinct was possibly the destruction of their habitat. It is not known why it has always been considered rare. Insufficient recording of the species does not seem to be the reason, because its former habitat was often thinned by hunters in the colonial times.
The rose-headed duck was in great demand with hunters and later as a decorative bird mainly because of its unusual plumage. Probably the last specimen was shot in Dabhanga , Bihar , India in 1935 by CM Inglis, who did not even know what he had shot before his dog, a retriever , brought him the bird. The hunted specimen later reappeared in the Government Museum in Madras in southern India - almost 1,000 miles from the place where the rose-headed duck found its end. It was exhibited here until the 1980s at the latest. Sir David Ezra, a European who lived in what was then British India , kept some of these ducks in his bird park in Calcutta until 1945 . In the past, some specimens were also kept in zoos and wildlife parks, including by Oskar Heinroth in the Berlin Zoological Garden (a drake between 1907 and 1908), by Jean Théodore Delacour in Clères , France and by Alfred Ezra in Foxwarren Park near Cobham , Surrey , England (from 1926 to 1932). For reasons unknown, the rose-headed duck never brood in human care.
literature
- Dominic Couzens : Rare Birds - Survivors, Evolution Losers and the Lost. Haupt Verlag, Bern 2011, ISBN 978-3-258-07629-4 .
- James Greenway: Extinct and Vanishing Birds of the World. Dover Publications Inc. New York, 1967, ISBN 0-486-21869-4
- Errol Fuller: Extinct Birds. 2000, ISBN 0-8160-1833-2
- Tim Flannery, Peter Schouten: A Gap in Nature: Discovering the World's Extinct Animals. Atlantic Monthly Press, New York, 2001. ISBN 0-87113-797-6 .
- Janet Kear (Ed.): Ducks, Geese and Swans. Oxford University Press, 2005, ISBN 0-19-854645-9 .
- David Day (1981): The Doomsday Book of Animals. Ebury Press, London, ISBN 0-670-27987-0
- Heinz-Sigurd Raethel : water and water ornamental poultry. Oertel + Spörer Verlags GmbH & Co, Reutlingen 2003.
- Hartmut Kolbe: Die Entenvögel der Welt , 2nd edition, Neumann Verlag, Radebeul, 1981
- Tim Halliday: Vanishing Birds. Their Natural History and Conservation. , 1978
- John Latham: Index ornithologicus, sive Systema Ornithologiae; complectens avium divisionem in classes, ordines, genera, species, ipsarumque varietates: adjectis synonymis, locis, descriptionibus, & c. London: Leigh & Sotheby, 1790.
- Steve Madge , Hilary Burn: Wildfowl. an identification guide to the ducks, geese and swans of the world. Christopher Helm, London 1988, ISBN 0-7470-2201-1 .
- Rory Nugent: The Search for the Pink-Headed Duck: A Journey Into the Himalayas and Down the Brahmaputra. Boston, Houghton Mifflin, 1991.
- S. Theodore Baskaran: Yet Another Rediscovery. In: The Hindu , Sunday Supplement, August 27, 1989.
Web links
- BirdLife International: Species Factsheet - Rhodonessa caryophyllacea
- Rhodonessa caryophyllacea inthe IUCN Red List of Threatened Species 2018.2. Listed by: BirdLife International, 2016. Retrieved March 3, 2019.
Individual evidence
- ↑ Bradley C. Livezey: A phylogenetic analysis of modern pochards (Anatidae: Aythini). The Auk 113, 1998, pp. 74-93. PDF
- ↑ Nigel J. Collar, AV Andreev, S. Chan, MJ Crosby, S. Subramanya & JA Tobias (Eds.): Pink-headed Duck. In : Threatened Birds of Asia: The BirdLife International Red Data Book , 489–501. BirdLife International, 2001, ISBN 0-94688-844-2 full text ( page no longer available , search in web archives ) Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.
- ↑ Kear, p. 629
- ↑ Kear, p. 629
- ↑ Kear, p. 630
- ↑ Kear, p. 629
- ^ Couzon, p. 224
- ↑ Dang, Nguyen Hong Hanh (editor) (2005): Latest search fails to locate Pink-headed Duck. Babbler 16: 21-22. PDF, 1.85MB ( Memento from March 10, 2012 in the Internet Archive )
- ^ Nguyen, Thi Ngoc Ha (editor) (2003): Pink-headed Duck survey in the Hukaung Valley, Myanmar. Babbler 8: 6-7 ISSUU, 2.1MB
