2248. Asarcornis scutulatus

(2248) Asarcornis scutulatus.

The White-Winged Wood-Duck.

Anas scutulata Muller, Verb. Land- en Volk., p. 159 (1839-44) (Java). Asarcornis scutulatus. Blanf. & Oates, iv. p. 424.

Vernacular names. Deo-hans (Assam); Hagrani Daop7dantu (Cachari).

Description. - Male. Head and upper part of neck white, thickly spotted with black, the black spots usually more numerous on the upper part of the head and neck; lower part of the neck and mantle glossy black, the whole of the lower parts rich chestnut-brown, more or less mottled, when freshly moulted, with glossy black on the breast and abdomen ; back, rump and upper tad-coverts olive-brown, glossed with metallic-blue and green; scapulars olive-brown ; smaller upper wing-coverts white, the median ones a soft blue-grey, broadly tipped with black, which is highly glossed in old males; quilts olive-brown, the secondaries with the outer webs bluish-grey, forming a speculum; the -first inner secondary white on the outer web, whilst the quill next it has a large white patch on the same web; under wing-coverts and axillaries white, the former with a few brown feathers mixed; tail blackish, glossed with green in old males.

Colours of soft parts. The bill varies from lemon-yellow to deep orange, the base and tip black and with black mottlings everywhere, generally least numerous about the centre of the bill; gonys paler, as a rule, than the rest of the bill. During the breeding-season the base of the maxilla becomes considerably swollen, though it never becomes an actual comb, whilst the orange colour deepens to deep orange-red or light red. The legs and feet vary, like the bill, from lemon-yellow to a dull orange. The joints, toes and webs are almost invariably mottled with dull greenish, and patches of the same colour are to be found on the tarsus itself. The toes are always dark. Irides brown or blood-red in old birds.

Measurements. Length about 750 mm.; wing 363 to 401 mm.; tail 127 to 178 mm. (according to condition); culmen 58 to 66 mm.; tarsus 54 to 60 mm.

Weight 7 1/2 to 9 1/2 lbs. when in good condition. An old male in captivity and very fat weighed 9 3/4 lbs. but wild birds seldom weigh more than 8 1/2 lbs.

In old males all the spots and the black of the upper parts are glossed with green and the bird in life looks a brilliant metallic green when in the sun. The gloss is green at the tip of each feather with a subtip of purple. The colour of the lower parts varies very much, both in depth of colouring and in the extent of the black mottling. In birds freshly moulted the colour is usually a rich red-ochre brown, the black mottlings - confined more or less to the tips of the feathers - being rather extensive. In faded plumage the lower parts are a pale dull earth-brown, with but little tinge of red and practically no black at all.

In the same way, by about July or August, the whole of the upper plumage becomes bleached and the gloss almost or quite disappears.

I think very old males become more white about the head and neck, more especially round the eye. A very fine male which was in my possession for some years became quite white for a space all round the eye and down the front of the neck.

The female does not differ conspicuously from the male, and birds in their first plumage are hardly distinguishable; on the whole she is not so highly coloured or quite so highly glossed, and perhaps has less black on the lower parts. The difference is, however, one only of comparison and a duck in good plumage is far more highly glossed and coloured than a male whose colours have begun to fade.

Colours of soft parts. Similar to those of the male but paler and duller; the bill is usually of a pale dull lemon, very rarely with an orange tinge and never with this tinge at all strongly developed; the black mottlings resemble those on the bill of the drake and vary to the same extent. In both sexes I have seen bills the ground-colour of which was almost obliterated by the spots and others, again, in which there were only a few small spots near the tip and base. The base of the upper mandible in the female is never swollen or red in colour. Irides are brown, never red-brown and certainly never blood-red.

Measurements. "Wing 305 to 356 mm. Weight 4 3/4 to 6 3/4 lbs.

Distribution. Eastern Assam, Burma South to Tenasserim. It is rare in Western Assam but occurs occasionally on the North of the Brahmapootra in Kamrup, Goalpara and Tezpur. In Lakhimpur it is common and it straggles through to Sibsagar, Naogang and Cachar but is very rare anywhere South of the Brahmapootra. Outside Burma it extends down the Malay Peninsula to Java and Sumatra.

Nidification. The Wood-Duck probably breeds from June to August but the only egg known is the one in my collection taken on the 30th of June from a large nest of sticks and rubbish placed in a fork of a great tree where three boughs branched out from the main stem. The so-called " nest " may have been an accumulation of rubbish or the nest of some Raptore, or may have been made by the Duck. The single egg it contained was a pearly-white, intensely glossy and fine-shelled, measuring 65.0 x 48.2 mm. Birds in captivity mated in June but none of mine ever laid eggs.

Habits. This Wood-Duck is a bird of the densest forests, frequenting those which are intersected by small and large pools and swamps, and well away from human beings. As a rule they keep in small flocks of half a dozen or less but often are found singly or in pairs. They fly with considerable power and speed, swim and dive well and walk as well and more quickly than geese. Their food consists of grain, shoots and buds of land-plants, fish, frogs, worms etc. but I have never known them eat any water-weed and they will take no dead animal, fish or insect food. Their breeding-call is a very fine trumpet, audible at a great distance; in addition they have many conversational croaks and guttural noises besides making a loud hissing when annoyed. During the heat of the day they remain quiescent in the deepest shade they can find, either floating on the water or perched on the bough of a tree.

BookTitle: 
The Fauna Of British India, Including Ceylon And Burma-birds(second Edition)
Reference: 
Baker, EC S (1922–1930) The fauna of British India, including Ceylon and Burma. Second edition. vol.6 1929.
Title in Book: 
2248. Asarcornis scutulatus
Book Author: 
Edward Charles Stuart Baker
CatNo: 
2248
Year: 
1929
Page No: 
387
Common name: 
White Winged Wood Duck
M_ID: 
381
M_CN: 
White-winged Duck
M_SN: 
Asarcornis scutulata
Volume: 
Vol. 6
id: 
5235

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