(2262) Tadorna tadorna.
Anas tadorna Linn., Syst. Nat., 10th ed., i, p. 122 (1758) (Sweden). Tadorna cornuta. Blanf. & Oates, iv, p. 427.
Vernacular names. Shah-chukwa, Safed-Surkhab, Rararia (Hind.); Thar-jo-niraji, Niraji (Sind).
Description. Head, upper neck and scapulars black, the first two richly glossed with green ; longer inner secondaries chestnut; a chestnut band including the back, the sides in front of the wing and across the breast; primaries blackish-brown; outer secondaries brown with a rich green speculum; a black or dark brown band along the centre of the breast and abdomen; under tail-coverts rufous; tip of tail black; the remainder of the plumage white.
Colours of soft parts. Iris brown ; bill deep fleshy-red to coral-red, the nail darker and brownish; legs and feet fleshy-pink to fleshy-red, claws black.
Measurements. Wing, 318 to 350 mm., 290 to 334 mm.; tail 108 to 125 mm.; tarsus about 50 to 58 mm.; culmen, 52 to 60 mm. with a large fleshy knob about 20 mm. high; 43 to 55 mm. with no knob.
Male in eclipse plumage has the head dull blackish with little gloss and pale exposed bases to the feathers; the feathers of the mantle are tawny with black tips; the black band upon the lower plumage has each feather tipped white.
Female similar to the male but duller and with the chestnut feathers edged with black vermiculations.
Young birds have the head and neck dull blackish, the feathers edged pale brown; interscapulars dark brown; there is no chestnut breast-band, though sometimes the sides are slightly suffused with chestnut.
Nestling. Above dark brown; the forehead, lores and obsolete supercilium white; a white patch on the interscapulars; below white, a brown patch on the thighs and a broad brown bar on the wings.
Distribution. Northern Europe to France and Spain; South Siberia and Central Asia. On migration South to Northern Africa, India, Burma, Japan, China and Formosa. In India it only occurs casually every Winter, very severe cold driving the birds further South than in mild seasons. It probably occurs every year in Sind, Punjab, North-West Provinces and Oude and more rarely South to Neemuch, Poona, Deccan etc, East it occurs in Assam and Eastern Begal and Behar. In Burma it is rare but has been obtained in Arrakan, Shan States etc.
Nidification. The Shelduck breeds during April and May, though a few may lay early in June. The eggs are deposited in a rabbit furrow or some similar hole and, where these are not available, in a natural crevice or hollow in banks and cliffs. The down is exceptionally luxuriant, forming a dense, soft white bed, wherever the site may be. The eggs number eight to sixteen and are a most beautiful pearly-white when first laid and, though as incubation proceeds they lose the wonderful lustre, they do not get so stained as do most ducks' eggs. The duck sits all day, the drake taking her place in the mornings and evenings when she feeds. The rabbit-holes selected are often in sand-banks with steep sides and the birds fly into these with wonderful dexterity, though, when the entrances are on flatter ground, they generally alight and walk into the holes. One hundred eggs average 65.7 X 47.3 mm.: maxima 70.0 X 47.3 and 69.0 x 50.0 mm.; minima 61.1 X 48.0 and 62.8 X 43.3 mm.
Habits. The Sheldrake is a sea duck rather than a bird of rivers and lakes and it is therefore only seen in India as it passes South to the sea-coasts. The few which do content themselves with fresh water frequent only such pieces as have large clean areas and sandy banks upon which they can walk and rest. They feed principally on small mollusca and Crustacea, water insects and such other animal food as they can pick up at low tide. They fly well, walk well and swim high and strongly but are poor divers. Their call is a loud, rather musical " kor-kor-korra," the duck's voice being more of a quack, though loud and resonant, whilst, in Spring, the male is said to have a low, clear whistle.