DUCK. Ducks are swimming birds, with short legs set far back and fully webbed feet, They are arranged in two groups or sub-families of the family Anatidre, which embraces also the mergansers, or shell-ducks, the geese and the swans. These constitute together the family coextensive with the order Anseres, whose distinctive feature is that the margins of the bill bear a series of transverse ridges, vary ing to a semblance to teeth in the mergansers, between which mud and water may be squeezed out by the closing of the bill, while the edible parts of the mouthful are retained. This crush ing-and-straining bill is usually broad and flat, often somewhat spoon-shaped, and contains a large, fleshy tongue with a horny tip. It is designed for crushing aquatic plants and other soft materials, for squeezing the nutrient out of mouthfuls of ooze and for picking up small, slippery animals.
Ducks spend most of their time on or about water, where they are powerful swimmers and so expert as divers that their name (i.e., the bird that ducks) refers to this characteristic. Cer tain species descend to considerable depths in search of food, but are not able to stay long nor move far under water. Many species habit ually sleep on the water, one foot dropped down and gently moving so as to keep the bird slowly turning about in nearly the same place. Adapted to this life, the plumage is exceedingly close, and is underlaid by a coat of down that pro tects the body from becoming wet or losing heat. In most species this plumage is different in the sexes, the male (or "drake") having as a rule richly colored dress—often of gaudy beauty — while the female (or "duck") is more soberly and protectively appareled. A distinc tive feature of the dress is the speculum, a patch of conspicuous color in the middle of the wing which is often brilliant in color but sometimes is pure white. Molting occurs twice annually, once in summer, when most ducks pluck the loosened down from their bodies and lay it on their nests as a covering for the eggs. This is so copious in the large eiders that it has become an article of commerce. The summer or "autumnal" molt is usually succeeded by a coat for winter wear which, in the drake at least, is far less gayly colored than his spring dress, acquired in his southern winter residence; and it renders him safer from his enemies. The quills of the wings and tail are molted in pairs (one from each side) at intervals, so that the power of flight is not lost.
All ducks are very strong and swift on the wing, and many of them make semi-annual migrations between the tropics and the shore of the Arctic Ocean, and their flight is known to attain a speed of 100 miles an 'hour for short distances in the case of certain species; yet a duck's wing is short and rounded.
Ducks naturally belong to all parts of the world except the Antarctic continent, and many kinds are very widely distributed. About 125 species are catalogued, of which 35 are to be found in North America, not counting the mer ganser, geese or swans. These fall into two groups distinguished less by structure than by habits and food. The first of these groups is that of the pond and river ducks (Anattnee), wherein no webbing connects the hind toe with the foot. The second group, in which the hind
toe has a lobe or web, is that of the sea-ducks and bay-ducks (Fuligulina).
The fresh-water or anatine ducks are better known than the others, for they visit or breed along rivers, lakes and ponds all over the country. They are not as expert divers as the sea-ducks, but prefer shallow and marshy waters, where they may pick up food from the bottom without serious diving, or gather it from the grassy margins. This food is chiefly vege table, consisting of seeds, grasses and roots, but they devour snails, aquatic insect-larva and any small, soft animal food met with. "The flavor of any duck's flesh ,l) remarks Grinnell, "de pends entirely on its food, and a bird of what ever kind which is killed after living for a month or two in a region where proper vege table food is to be found will prove delicious eating?' Reverse conditions will spoil the taste of species highly reputed. "Thus the fine feath ers of a canvas-back are not necessarily a guarantee that the bird wearing them possesses the table-qualities that have made the species famous." The river and pond ducks, of which about a dozen species are native to North America, are most familiar; and one of them, the mal lard (Alias' boschas) is the "wild" duck of popu lar speech, for it is well known throughout the whole northern hemisphere. Its head and throat are glossy green, varying to bluish black; a white ring surrounds the neck; the breast is chestnut; the belly grayish; back and tail brown to black; speculum rich purple edged by lines of white and black. The female has a much duller dress. The mallard is migratory, breeding from the northern United States to Alaska and Greenland, and wintering from the central United States southward. At these seasons it is found beside all the interior waters and for merly was extremely numerous; but the civiliza tion of the country, the draining of the marshes and wasteful shooting previous to the enactment of recent protective laws, have caused an alarm ing decrease of this handsome and valuable fowl. Its nesting is after the manner of its race, which is described as follows by Dr. F. M. Chapman: °All our Anatime except the wood-duck, nest on the ground, lining a slight hollow with grasses, leaves, moss or rootlets, and with more or less down from the breast of the incubating bird. . . . The nesting-site is usually near water. . . . The generally greenish, cream or buff eggs number from 6 to 14 and hatch within a surprisingly short time of each other. Incubation is performed by the female alone. . . . Few birds show more concern for the safety of their offspring than do the wild ducks. When danger threatens, the young, evidently acting under direction, scatter and seek cover in every direction, while the female gives a remarkable and courageous exhibition of partial helplessness." The mallard is the original stock from which most of the domestic races of ducks have been derived ; and wild pairs of these ducks are still used to breed their race in cap tivity in many parts of the United States and elsewhere. A considerable part of the market supply in eastern American cities comes from this source.