97. THE COMB-DUCK.
Sarcidiornis melanonota, (PENNANT).
Primaries uniformly black. Axillaries black. Head and neck white, mottled with black.
MALE: Lower back grey; rump black; wing about 15.
FEMALE : Lower back and rump grey; wing under 12.
VERNACULAR NAMES :—Nukta, Hind.; Nakwa, Chutia Nagpur; Naki hansa, Uriya ; Jutu chilluwa, Telugu ; Dod sarle haki, Canarese ; Neer koli, Coimbatore ; Tau-bay, Burmese.; Bowkbang, Karen.
THE Comb-Duck, Nukta, or the Black-backed goose of Dr. Jerdon, is found as a permanent resident over almost the entire Indian Empire.
On the north-west, its limits are the Ravi and Indus rivers. On the north, it is found to the foot of the Himalayas, but it does not appear to enter the valleys. From the Himalayas, this species extends down to Ceylon, being rare or absent from some of the tracks of country which are very dry and naturally unsuited to its habits.
This Duck extends throughout Assam and thence southwards to the southern limits of Pegu. To the east its range spreads out to the Southern Shan States, where, as Major G. Rippon informs me, it is common as far as Mone at least. It has not been procured in Tenasserim.
It is not a common bird in Upper Burma, and none of my friends appear to have met with it, except Captain F. T. Williams, who informs me that this Duck occurs on the Chindwin river, and Major J. H. Sewell, who tells us in the pages of the Journal of the Bombay Natural History Society that he shot it near Kyoukse, and that it is common at Yamethin, where it also breeds.
The Comb-Duck of India is identical with the Comb-Duck which is found over a considerable portion of Africa and in Madagascar.
The Comb-Duck occurs chiefly in the plains, but in suitable localities it may be found up to an elevation of 2000 feet or upwards. It affects tanks and swamps which arc covered with weeds and are surrounded by jungle, and it is comparatively seldom seen on large streams. It does not, however, avoid the smaller streams if these have a sluggish current and run through jungle. These Ducks may be generally observed in pairs, but when at rest during the day I have seen as many as twenty or thirty together. They are heavy, clumsy birds, but, when once on the wing, they fly well. They are not particularly wary, and I have seldom found any difficulty in approaching a flock. They seem to feed mostly in the mornings and evenings, and they spend the hotter part of the day resting on banks or perched on some big bough of a tree. This Duck feeds almost entirely on the water, eating water-plants and the various small forms of animal life found in water. At times it appears to be partial to young rice and grass. As an article of food, the flesh of the Comb-Duck is not comparable with the flesh of many of the migratory Ducks, but it is very palatable when fairly young, and not to be despised even in the case of the older birds. The note of this Duck is seldom heard, and has been variously described as a low guttural quack-like sound, and as a loud cry more like that of a goose than of a duck. According to Mr. Stuart Baker it also utters loud trumpet-calls. When wounded this species dives well and is very difficult to catch.
The Comb-Duck breeds in the rainy season from the end of June to September, according to locality and rainfall, but in Ceylon it appears to breed in February and March.
The nest is almost invariably built in a natural hollow of a large tree, or on a fork formed by three or four large branches. It is sometimes, however, placed in holes of old ruined forts, and sometimes the Comb-Duck appropriates the deserted nest of some large bird of prey. Mr. Hume once found a nest in a regular swamp at one end of a jhil, in amongst a thick growth of sedge and rush. Mr. E. H. Aitken once found the nest in a hole in a bank of a stream, as recorded in the Journal of the Bombay Natural History Society. I reproduce a portion of Mr. Aitken's note. He says :—
" On the 30th of August, eighteen years ago, I was wandering about with my gun on the banks of a small brackish stream, near Kharagora, when a female Comb-Duck got up and went off. I fired and missed her. She flew on for some distance, then turned and came back straight for me, and I killed her. She was handed over to the cook, and in the course of the day he came to say that he had found an egg in her. It was ready to be laid, and there was no appearance of any more, so I concluded that the bird had made its nest and laid all its eggs but one when it had the misfortune to fall in my way. Next day I took two men with me to the place, and began a systematic search for the nest. There were scarcely any trees in the neighbourhood, but many patches of rank rushes, and among these I hunted long without success. At last one of my men, who was on the other side of the stream, signalled to me and pointed to a hole in the bank, which at that part was quite perpendicular. I crossed, and, looking into the hole, found sixteen eggs which exactly matched the one taken out of the body of the bird. They were lying on a bed of twigs and quill feathers of some large bird, with a little lining of down and some fragments of a snake's skin. The hole was about five feet from the ground and two feet deep, the entrance being about nine inches wide by six deep. The hole went into the bank quite horizontally, and there was nothing in the way of a ledge to alight on at the entrance, so the bird must have popped in as a pigeon does."
The nest is generally composed of dead leaves and grass on a foundation of a few sticks. The eggs vary in number from eight to fifteen or twenty, and, in one remarkable instance mentioned by the late Mr. A. Anderson, they numbered forty. In shape many of the eggs are regular ellipses, others are slightly more pointed at one end than at the other. They are remarkably smooth, and they have a large amount of gloss when first laid. In colour they are creamy white. They measure from 2.2 to 2.6 in length, and from 1 .65 to 1.8 in breadth.
The male has the head and neck white, mottled with black, but more thickly on the crown than elsewhere. The mantle and the whole lower plumage are white, each feather, for some time after the autumn moult, having a narrow black margin. The sides of the body are pale grey; the axillaries black; the under wing-coverts black, with some of the central feathers margined with white. The upper back, the scapulars, the lesser coverts, and the inner secondaries are glossy blue-black. The primaries are plain black; the secondaries are dark brown on the inner web, metallic bronze-green on the outer. The greater wing-coverts are entirely bronze-green. The lower part of the back is grey; the rump, upper tail-coverts and tail black. The black of the upper part of the back is produced as a broad crescentic band on either side of the upper breast.
The female bears a close general re¬semblance to the male, but is much smaller, and differs also in having the metallic black portions of the plumage less glossy; the rump of the same grey colour as the lower back; the mantle brown with whitish margins; the under wing-coverts entirely black; and the sides of the body brown.
Many birds have the white lower plumage suffused with ferruginous.
Young birds, after the first moult, are brownish above and dingy white below.
Male : length about 30; wing 15 ; tail nearly 6. Female: length about 27; wing about 11 1/2; tail rather more than 4. In both sexes, the bill is black; the irides dark brown; the legs and feet dark plumbeous. The comb of the male is black. Weight up to 5 3/4 lb.