Harteman Wildfowl | kvk 90846257 | ubn 6872294

White-winged wood duck

Asarcornis scutulata (Cairina scutulata)

Witvleugelboseend/ Malaienente/ Canard à ailes blanches


This White-winged Duck or White-winged Wood Duck is listed as Endangered by the IUCN because it has a very small and fragmented population which is undergoing a very rapid and continuing decline as a result of the loss of and disturbance to riverine habitats. The duck was historically widely distributed from north-eastern India and Bangladesh, through South-East Asia to Java and Sumatra, Indonesia.


The duck (Asarcornis scutulata) is a large species of duck, formerly placed in the genus Cairina and allied with the dabbling ducks. However, mtDNA cytochrome b and NADH dehydrogenase subunit 2 sequence analysis and the biogeographicalpattern of distribution indicate that the anatomical similarity to the Muscovy Duck is deceiving. Thus, this species might more appropriately be placed in a monotypic genus, as Asarcornis scutulata, which appears to be unrelated to the Muscovy Duck but closer to the diving ducks.


Variation in colour of underparts, at least in mainland populations, from chestnut-brown with black collar to all black, and in amount of iridescence on neck and mantle, suggested to be age-related (Wells, 1999). Indonesian populations reportedly smaller, with more extensive white in plumage; birds similar to continental “leucoptera” represent < 20% of individuals on Sumatra, while extent of white on body in birds on same island is apparently highly variable, but in specimens is generally more than that shown by mainland S Asian birds, and some in SE Sumatra are apparently almost entirely white but for the black primaries, secondaries, scapulars and rectrices; Sumatran birds also appear to have more rounded head, longer neck, smaller body and shorter, more curved bill than typical “leucoptera”, with perhaps redder bare parts (J. Kear, 2005). 




Above: male white-winged wood duck at Sylvan Heights Bird Park, USA (2009)


It has undergone a dramatic decline, such that its population is now estimated at c.1,000 individuals, comprising c.200 in LaosThailandVietnam and Cambodia, c.150 on Sumatra,Indonesia, c.450 in India (Choudhury 2000) and Bangladesh (A. Choudhury in litt. 2007) and in the "low hundreds" in Myanmar (J. C. Eames in litt. 2007) following the identification of a significant population numbering tens of individuals in the proposed Hukuang Tiger Reserve. It has also recently been recorded in Bhutan (Choudhury 2007). It continues to decline throughout its range, and is probably extinct in Malaysia and on Java. The only recent records from Vietnam are from watercourses in dry dipterocarp forest in Yok Don NP, where it is rare but probably under-recorded (Eames in litt. 2012). It is likely to be extirpated elsewhere due to widespread forest and wetland destruction. There are no confirmed recent records from Laos, however, a few birds probably survive in the Nam Theun catchment (W. Duckworth in litt. 2012). In Myanmar it is locally common on ox-bow lakes within the Chindwin basin (Tordoff et al. 2007). In India, it has been recorded from Arunachal Pradesh, Assam, Meghalaya, Nagaland and Manipur (no recent report), with unconfirmed reports from Tripura and Mizoram. Its current distribution is chiefly in the eastern lowlands of Assam and Arunachal Pradesh (A. Rahmani in litt. 2012). 


There has not been a comprehensive analysis of recent records, but estimates of c.450 in India (A. Choudhury in litt. 2007), low hundreds in Myanmar and c.100 in Cambodia (J. C. Eames in litt. 2007) combined with an earlier estimate of 150 in Indonesia suggest that the species's population may precautionarily be considered to lie within the band 250-999 mature individuals. This equates to 375-1,499 individuals in total, rounded here to 350-1,500 individuals.


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, especially on plateaux supporting sluggish perennial rivers and pools.


Its decline is largely attributable to the destruction, degradation and disturbance of riverine habitats including loss of riparian forest corridors. The resultant small, fragmented populations are vulnerable to extinction from stochastic environmental events, loss of genetic variability, disturbance, hunting and collection of eggs and chicks for food or pets. Hydro-power development, inappropriate forest management, and pollution are more localised threats. It may be particularly susceptible to loss of large trees with nesting holes (W. Duckworth in litt. 2006).


White-winged ducks from Moluccan islands

At the Natural History Museum at Tring two specimen (male and female) show very much white as you would expect from the Sumatran/ Javan population. These skins were labelled location MoluccasBased on current knowledge, these birds must have been collected in Sumatra or Java in the past. 


The specimens as mentioned above were received at NHM Tring  by G.A. Frank in 1864. Frank, who was a dealer in natural history objects in Amsterdam, sold specimens to museums. Frank himself did not go out to collect animals, but he bought them from people who did, and then sold them to collectors. He has also bought many "duplicates" from Leiden and sold them to other museums such as the English NHM. Because Frank did not collect himself, and therefore probably did not always know where the objects came from (had been collected), he would occasionally have made up something, or made mistakes, when it came to the origin. It is therefore quite possible that these two specimens originally came from Leiden, via Frank. Perhaps at that time Frank had many birds from Leiden which indeed came from the Moluccas, and therefore he thought these ducks should come from there. We will probably never know. For the time being it is the most safe to assume that the Moluccas mentioned on the labels are incorrect (Hein van Grouw, 2019). 


The duck is a resident species which does not venture far from its forest habitat other than to visit feeding waters; therefore it would seem most unlikely there has been a recent population south east of Sumatra, there having been no record of this duck on Borneo or the Celebes islands. The barrier would have been the sea journey - so even in the distant past when there was a land bridge from Malaysia to Sumatra/ Java there was no such bridge to Sulawesi and eastwards to New Guinea (M.J.S.Mackenzie, 2019)



Above: White-winged wood ducks (male on top, female on bottom), possibly collected in Sumatra/ Java, but mislabelled from the Moluccas, by G.A. Frank. 

Specimens from the Natural History Museum at Tring, UK (Harteman, 2019).



Above: White-winged wood ducks (close-up label), possibly collected in Sumatra/ Java, but mislabelled from the Moluccas, by G.A. Frank. 

Specimens from the Natural History Museum at Tring, UK  (Harteman, 2019).


Conservation actions
Conservation Actions Underway

CITES Appendix I. The Wildfowl and Wetlands Trust produced, and implements, an action plan for the species. In 1993, 21 protected areas were known to support populations. Dibru-Saikhowa National Park and Dihing-Patkai Wildlife Sanctuary, both in Assam, were established because of its importance for this species, while a significant population is in Nameri National Park (see Das and Deori 2011, A. Choudhury in litt. 2016). Sylvan Heights owns a number of captive breeding birds in the US however, few, if any, reintroduction attempts have been made (Kivi 2010, Sylvan Heights Bird Park). Captive breeding programmes have also taken place at Slimbridge (UK), Bardobi Tea Estate (Assam) and Miao Zoo (Arunachal Pradesh), but the eggs and chicks developed Tuberculosis and so no reintroduction took place (A. J. Green and H. Yahya in litt. 2016). Conservation awareness materials depicting it have been widely distributed in Laos and Cambodia.


Conservation Actions Proposed

Conduct further surveys to clarify its distribution and status. Instigate regular monitoring of selected key populations. Promote strict enforcement of hunting regulations and minimise encroachment, disturbance and habitat degradation in all protected areas supporting populations. Campaign for increased protection of peat-swamp forest in Sumatra and moist lowland forest in other range states (A. J. Green in litt. 2016), and provide more effective protection to reduce illegal activities in habitats where this species occurs (Yahya, 1994). Campaign against pesticide and oil pollution at key sites in north-east India. Promote more widespread conservation awareness campaigns in and around key protected areas. Rapidly introduce the measures outlined above in newly discovered strongholds, e.g. northern Myanmar. Ensure that captive breeding centres maintain healthy populations of this species, and ensure that diseased individuals are not able to escape and thus potentially spread disease in wild populations (Yahya, 1994).


More information: https://www.iucnredlist.org/species/22680064/110103586



Above: White-winged wood ducks at the Wildfowl & Wetlands Trust, Slimbridge, UK (2016)

Left male, right female.



A brief history of the first white-winged wood ducks known in captivity

From: A Natural History of the Ducks (1922, John C. Phillips), Volume I

Behaviour in Captivity. Baker kept many of these birds in confinement. They tamed very readily and did not attempt to fly off except at the approach of the breeding season. In fact, after having been thus tamed, they never made use of their wings, but walked long distances to and from the water, as much as half a mile in one case. Their gait, and their style of swimming according to Finn (1915) are different from those of the Comb ducks and sheldrakes, and resemble rather those of the true ducks. The swelling of the drake's bill in the spring is similar to what takes place in the common sheldrake. Baker's birds died very quickly when sent to the Calcutta Zoological Gardens and in his aviaries always kept out of the sun from 10 a.m. to 2 p.m. even in the cool weather. He found them very well behaved and never quarrelsome. Probably if Baker's birds had nested in confinement, they would have become more pugnacious. Some lesser whistling duck (Dendrocygna javanica) shared the same yard and never came to any harm. When not feeding, the White-winged wood ducks almost invariably sat on perches, but they kept their position chiefly by balance of the body, never by grasping of the feet. These caged birds very seldon called, except occasionally in April and May. One female which died in June contained eggs larger than those of a hen. The birds paired regularly in May, the base of the drake's bill becoming swollen and red, but the ducks never laid any eggs. 


Finn (1915) remarks that a single female in the London Zoological Gardens often made a spiritful grab at some smaller waterfowl. In 1851 the London Zoological Gardens received two specimens from Mr. Blyth, but there was none living in the Gardens in 1883 (Sclater, 1883). In 1905, five specimens arrived in England and were sold for twenty pounds the couple (Hubbard, 1907). So far as I know, no living specimens have been received in America (Phillips, 1922).


Mr. Blaauw tells me that he saw living specimens of this duck some years ago on the Duke of Bedford's estate in Engeland (Phillips, 1922), and that they did not live many years. He was much struck with the Muscovy-like appearance of the species. 


Domestication. There are various references to mottled or piebald specimens from Sumatra and Java, and these have been explained on the assumption that the birds were breeding in domestication. This, however, seems to me very impropable because the species has given no evidence of easy domestication. There are instances of considerable changes of plumage after many years of captivity which may account for these freak plumages. The possibility of a distinct southern race (leucoptera) of this species as suggested by Hume and Marshall (1879) still exists. 



From: The White-winged Wood Duck, M. J. S. Mackenzie and Janet Kear (Wildfowl 27, 1976, p5-17)

White-winged Wood Duck have never been common in captivity, although a pair was exhibited at the London Zoo as early as 1851 (Sclater 1880). Others were held from time to time in England, the Netherlands and in France. Baker (1908, 1921) kept many birds in confinement in Assam, and sent some to Calcutta Zoo. None bred until 1936 when the female of a pair, imported two years earlier to a waterfowl collection near Rotterdam, laid eggs from which five ducklings were hatched and reared. They had been kept in a small pen, measuring 15m x 15m, shaded by trees and long grass, and containing a small central pond (Schuyl, 1937). 

A shipment of ten Wood Duck to the Wildfowl Trust at Slimbridge, England, from Thailand was made in 1955 but none of these birds nested. Then in 1969, as part of World Wildlife Fund Project 406, M.J.S.Mackenzie sent five males and one female (hand-reared from wildcaught ducklings in Upper Assam) to the Wildfowl Trust, and these were joined by two more males and four females in 1970.

The second breeding in captivity occurred at Slimbridge in 1971 ; the first captive-bred female to lay did so at the Trust’s refuge at Peakirk in 1973, and in 1974 a pair, both members of which were second-generation captives, bred at Slimbridge. 

Production in England is shown in Table 1 below (Johnstone 1972; Lubbock 1975, 1976). 

Two ducklings have also been reared at Gauhati Zoo, Assam, from birds supplied by M.J.S.M. Captive adults are currently held at Gauhati (9 individuals), Koom song Tea Estate, Assam (5), by the Wildfowl Trust (three reserves holding 41 birds), at Bentley, Sussex (2), Jersey Zoo (2), Clères, France (6), Washington Zoo, USA (4), and the Botanic Gardens, Hong Kong (2), and so total about 70 individuals.

All captive birds outside India are related to the Slimbridge stock, and those in Assam come from the same wild area as the Slimbridge birds.




In captivity, the birds have always used boxes. Schuyl’s (1937) female laid in one set about 1 m from the ground. At Slimbridge a structure something like a dog kennel and measuring roughly 60 x 45 cm, with 16 cm sides was selected (Johnstone 1972), and a similar box has been used at Peakirk. Lubbock (1975) advocated boxes 60 cm in length, 30 cm wide and 30 cm high.




Of an original shipment of ten wild-caught birds from Thailand to Slimbridge in 1955, the last bird died during 1961 after six years in captivity. Six post-mortem reports are available: one bird died o f aspergillosis soon after arrival, and five others succumbed to avian tuberculosis. The oldest individual of the 1969 and 1970 shipments is now aged seven-and-a-half years. Twenty-three of these birds and their offspring have died aged six months or over, and all except three had tuberculosis. Two individuals developed lead poisoning after ingesting shot-gun pellets,three had Acuaria infestations (two as well as tuberculosis) and two also had aspergillosis.
Juveniles have died from Acuaria, tapeworms, nephritis, aspergillosis and pneumonia. One young female left with her parent in an aviary died, aged only 4j months, of a combination of tuberculosis and Acuaria. As sometimes happens with other neartropical waterfowl, some young reared by their mothers became stunted— growing slowly in comparison with the rest of the brood— and some of these runts developed rickets.


More information: Wildfowl 27, 1976, page 5-17 (PDF)



From: The Waterfowl of the World (1959, Peter Scott), Volume III

White winged wood ducks have always been scarce in captivity, although they came to the London Zoo as early as 1951. They usually arrive in a weak condition; once acclimatized, they live well and long. They eat grain, but also need some animal food, and they readily catch very small fish. They prove hardy, like Muscovies, but unlike the latter, they never molest other birds and do not fight between themselves if sufficient space is allowed them. They never nested at Clères, nor at Foxwarren, and the only record of breeding in captivity is that of D.G. Schuyl, in Holland, in 1936. A pair imported in 1934, placed in a pen of 50 x 50 feet, with some trees, long grass, and small pond in the middel, were first very shy, but later on became tame. In May, after two years, the female went into a box set about three feet above the ground and laid seven eggs, wich hatched under a domestic hen. M. Schuyl describes (L'Oiseau, 1936, pp. 171-172) the eggs as greenish yellow, rather long and relatively small. The incubation period was about thirty days, the eggs having been slightly incubated before removal. The chicks' first plumage is described as dark brown, the head and neck deeper than the body, the bill lead grey tinged with reddish brown, the legs very dark brown. They grey rapidly and at two months began to assume the dress of adults. Five were reared. There are, at present, few specimens living in the Wildfowl Trust collection.



Above: white-winged wood ducks as pictured in Siergevogelte (1941, C.S. th. van Gink).
This is probably Schuyl's breeding pair (1936) - world's first breeding pair described, or some of their offspring. 




Above: female White-winged wood duck at Sylvan Heights Bird Park, USA (2005)



Above: female White-winged wood duck at Sylvan Heights Bird Park, USA (2005)



Above: White-winged wood duck at Sylvan Heights Bird Park, USA (2005)



Above: White-winged wood duck at the Wildfowl & Wetlands Trust, Slimbridge, UK (2016)



Above: Group of White-winged wood ducks at a Dutch private collection of Peter Kooij (2012)



Above: The author and a female winged-winged wood duck female (2015)



Above: suitable nestboxes for white-winged wood ducks (at Sylvan Heights Bird Park, NC, USA, 2016)



Above: white-winged duckling (1 day old)



Above: white-winged duck female and ducklings at Harteman Wildfowl (2018)



Above: white-winged duck female and ducklings at Harteman Wildfowl (2018).



Above: white-winged duckling, one month old, at Harteman Wildfowl (2018).



Above: white-winged ducks at two months of age, at Harteman Wildfowl (2018). 


Above: white-winged wood duck preening and courtship


Above: footage of the white-winged duck breeding project in the USA (2016).


White-winged wood duck is hiding something... at Harteman Wildfowl (2018)

Powered by liveSite Get your free site!