Not at all a familiar bird at home, the gadwall is, in the East, the most abundant of all the larger winter ducks, and holds much the same place in shooting in most districts as mallard in the west. , The female is very like the female mallard, having a similar mottled-brown plumage, but the bar on the wing is all white and there is generally a little chestnut in front of it. The drake is a very poor creature compared to the splendid mallard drake; his head is of a dull speckly brown and the pencilled grey of his body is dark and dull in tone, the only striking note of colour being the velvet-black stern. The white wing-bar is preceded by a patch of reddish-chocolate.
Plain as his plumage is, the gadwall drake yet changes it for female dress, like the mallard, in the summer; indeed he goes further and changes his black bill for the orange-edged one of the female, but the distinct chocolate patch on the wing remains to distinguish him. Young males have less of this.
Gadwall are finer-boned and more delicately framed ducks than mallards, and are not quite so large, although they have a plump appearance ; the drake seldom weighs over two pounds, and the duck does not reach that weight, and may be as little as one; they are generally in good condition, even when recently arrived, at which time ducks are apt to be poor after their exertions in the long flight.
Although they penetrate to most parts of the Empire, they are not so widely distributed as the pintail or even the humble shoveller, to say nothing of the teal, for they do not visit the extreme south of India nor Ceylon, to say nothing of the islands of the Bay. They come in about November and may stay on as late as May, though March is the more usual month for their departure. They are found in flocks of various sizes, and are not naturally remarkable either for shyness or its opposite, though after persecution they give trouble enough to the gunner. Like mallard they rise smartly, and their flight is more rapid, and somewhat teal-like both in style and sound. They sit rather high in the water, and swim and walk with ordinary ability, not infrequently coming ashore to feed; among the items there sought for Hume enumerates small moths and butterflies—rather ethereal diet for a duck one would think, especially as so few birds have been actually observed eating butterflies at all. Water-insects and shell-fish are also partaken of, but the gadwall is mainly a vegetarian feeder, especially appreciating wild rice and paddy, even when half ripe. It is almost always an excellent bird for the table.
Gadwall like a certain amount of cover in the water they frequent, but are not particular birds about their habitat; then visits to the rice-fields are made in the mornings and evenings, and by day they retire to the broader waters to rest. They seem confined to fresh water. Although not bad divers when urged by necessity, they do not seem to dive for food; this, of course, is what one would expect, but there exists an old statement to the effect' that the gadwall dived freely and frequently; this was probably founded on observation of some unusually gifted individual bird. The gadwall's quack is more shrill than that of the mallard, and weaker and sharper, and more often used, according to Hume. This presumably refers to the female; the male, which is pretty noisy towards spring, has a gruff, grunting quack, not at all like a mallard drake's note, or indeed like that of most male ducks, though the shoveller and clucking-teal have voices of somewhat the same type.
Gadwall are not only thought highly of by sportsmen, but seem to be popular in pond society ; they are found, according to Hume, in the company of all sorts of other ducks, and are even tolerated by geese, who usually maintain an attitude of disagreeable exclusiveness. The gadwall drake shows off to his mate in the same attitudes as the mallard, at which time the sudden exposure of his snow-white wing-bar has a curious flashing effect against the dull iron-grey plumage. In captivity he is a devoted mate, vigorously defending his chosen duck, and strictly refraining from aggression towards the mates of his neighbours, a virtue not so common among ducks of the mallard group as it might be. He is, in fact, the typical, good, steady, reliable bird of his tribe. Outside India the gadwall has the same wide range all round the northern parts of the world as the mallard, but it is not always equally common everywhere; it is not, for instance, abundant at the very far end of Asia any more than in Britain. The Bengali name is Being-hans, the Nepaulese Mail, the Sindhi Burd; while other appellations are the Hindustani Bhuar and Beykhur.