The white-winged duck or white-winged wood duck (''Asarcornis scutulata'') is a large species of

duck Duck is the common name for numerous species of waterfowl in the family Anatidae. Ducks are generally smaller and shorter-necked than swans and geese, which are members of the same family. Divided among several subfamilies, they are a form ...

, formerly placed in the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

''Cairina'' with the

Muscovy duck The Muscovy duck (''Cairina moschata'') is a large duck native to the Americas, from the Rio Grande Valley of Texas and Mexico south to Argentina and Uruguay. Small wild and feral breeding populations have established themselves in the United St ...

(''Cairina moschata'') and allied with the dabbling ducks. However,

mtDNA Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, such as adenosine triphosphate (ATP). Mitochondrial DNA ...

cytochrome ''b'' and

NADH dehydrogenase NADH dehydrogenase is an enzyme that converts nicotinamide adenine dinucleotide (NAD) from its reduced form (NADH) to its oxidized form (NAD+). Members of the NADH dehydrogenase family and analogues are commonly systematically named using the for ...

subunit 2

sequence In mathematics, a sequence is an enumerated collection of objects in which repetitions are allowed and order matters. Like a set, it contains members (also called ''elements'', or ''terms''). The number of elements (possibly infinite) is calle ...

analysis indicate that the anatomical similarity to the Muscovy duck is deceiving and that the species is appropriately placed in a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...

genus, as ''Asarcornis scutulata'', which is evolutionarily closer to the

redhead Red hair (also known as orange hair and ginger hair) is a hair color found in one to two percent of the human population, appearing with greater frequency (two to six percent) among people of Northern or Northwestern European ancestry and ...

(''Aythya americana'', one of the

diving duck The diving ducks, commonly called pochards or scaups, are a category of duck which feed by diving beneath the surface of the water. They are part of Anatidae, the diverse and very large family that includes ducks, geese, and swans. The diving d ...

s).

Description

This is one of the largest living species of duck next only to the steamer ducks which are heavier. The Muscovy duck also attains sizes that nearly rival the white-winged duck, but may average a bit smaller in a wild state. Length is and wingspan is . Males weigh , while females weigh .''Cairina scutulata'' – White-winged duck
wildpro.twycrosszoo.org''CRC Handbook of Avian Body Masses, 2nd Edition'' by John B. Dunning Jr. (Editor). CRC Press (2008), . The most noticeable feature on adult birds, is the dark body contrasting with a whitish head and neck. Males have mostly dull yellowish bill, blackish mottling on the head and upper neck, white lesser median coverts and inner edges of tertials and bluish-grey secondaries. In flight, white wing-coverts contrast with the rest of the wings. Females are smaller and usually have more densely mottled head and upper neck. The juvenile is duller and browner.White-winged Duck ''Cairina scutulata''
Birdlife International. birdlife.org This secretive species is only known to feed at night. Its diet consists of seeds, aquatic plants, grain, rice, snails, small fish and insects. It inhabits stagnant or slow-flowing natural and artificial wetlands, within or adjacent to evergreen, deciduous or swamp forests, on which it depends for roosting and nesting, usually in tree holes. Although lowlands (below c.200 m) provide optimum habitat, it occurs up to 1,400 m of altitude, especially on plateaus supporting sluggish perennial rivers and pools. File:White-winged Duck RWD3.jpg, At Nameri National Park, Assam, India File:White-winged Wood Duck (Cairina scutulata) RWD.jpg File:Malaienente Cairina scutulata 0505054.jpg

Distribution and status

Historically, the white-winged duck was widely distributed from northeastern

India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...

and

Bangladesh Bangladesh (}, ), officially the People's Republic of Bangladesh, is a country in South Asia. It is the eighth-most populous country in the world, with a population exceeding 165 million people in an area of . Bangladesh is among the mos ...

, throughout

South East Asia Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia, South-eastern Asia or SEA, is the geographical south-eastern region of Asia, consisting of the regions that are situated south of mainland ...

Java Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's mos ...

and Sumatra. It is now extinct in Java. In India, the duck is found only in the northeastern part of the country, with the main concentration in eastern Assam and adjacent areas of Arunachal Pradesh. However, in 2002 it had a population of only 800, with about 200 in Laos,

Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is b ...

Vietnam Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making i ...

and Cambodia, 150 on Sumatra, notably in Way Kambas National Park and 450 in India, Bangladesh and

Burma Myanmar, ; UK pronunciations: US pronunciations incl. . Note: Wikipedia's IPA conventions require indicating /r/ even in British English although only some British English speakers pronounce r at the end of syllables. As John Wells explai ...

. In India, the key protected areas for the white-winged duck are Dibru-Saikhowa National Park, Dihing-Patkai Wildlife Sanctuary, Nameri National Park and Namdapha National Park. The white-winged duck occurs in dense tropical evergreen forests, near rivers and swamps. They tend to nest in tree cavities, and are threatened in part since the destruction of hollow trees is destroying their nesting localities. The draining of swamps and rivers and other forms of

habitat destruction Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...

is also destroying the habitat that they could survive in. Additional threats include loss of genetic variability, disturbance, hunting, and collection of eggs and chicks for food or pets. Due to ongoing habitat loss, a small population size, and because this duck is hunted for food, eggs and pets, the white-winged duck is evaluated as

Endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and in ...

on the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...

of Threatened Species. It is listed on Appendix I of

CITES CITES (shorter name for the Convention on International Trade in Endangered Species of Wild Fauna and Flora, also known as the Washington Convention) is a multilateral treaty to protect endangered plants and animals from the threats of interna ...

. The white-winged duck is also found in the central Sumatra province of Riau, specifically in the peatland '' Acacia'' plantations of a large pulp and paper company. The plantations, at least temporarily, provide suitable habitat between periodic harvests (once every 4–5 years). The ducks are frequently observed along canals where large and overhanging ''Acacia'' trees provide shade and cover from predators and a haven in which to feed and rest. The quiet and still water in the canals of the plantations provides an undisturbed and secluded location, away from local communities which may hunt the ducks or collect their eggs. Nearby, natural forest conservation areas and greenbelts also provide suitable nesting and roosting habitat in close proximity to the canals. It is the state bird of the Indian state of

Assam Assam (; ) is a state in northeastern India, south of the eastern Himalayas along the Brahmaputra and Barak River valleys. Assam covers an area of . The state is bordered by Bhutan and Arunachal Pradesh to the north; Nagaland and Manipur ...

. There have been efforts to preserve the population by breeding in captivity in England. It has been seen that they do well under shady, dimly-lit conditions, but there is also a higher chance for them to contract avian tuberculosis.

References

External links

* {{Taxonbar, from=Q25495361 white-winged duck white-winged duck Birds of Southeast Asia Birds of Northeast India Fauna of Assam white-winged duck Symbols of Assam