DUCK

(from Dutch doek, cloth), any of a broad range of strong, durable, plainwoven fabrics made originally from tow yarns and subsequently from either flax or cotton. Duck is lighter than canvas or sailcloth and differs from these in that it is almost invariably single in both warp and weft, or filling. The fabric, in its various qualities and colours, is used for an enormous variety of goods, including tents, wagon and motor hoods, light sails, belting, mailbags and other bags and pocketings, and clothing; the plural form is used colloquially for trousers made of the material. Russian duck is a fine white linen canvas. any of several genera of relatively small, short-necked, large-billed waterfowl that belong to the subfamily Anatinae, family Anatidae (q.v.), order Anseriformes. In true ducks, i.e., those classified in Anatinae, the legs are placed rearward, as in swans, resulting in a waddling gait. Most true ducks, including a few inaccurately called geese by reason of size and build, differ from swans and true geese in the following characteristics: males molt twice annually, females lay large clutches of smooth-shelled eggs, and both sexes have overlapping scales on the skin of the leg and exhibit some degree of sexual differentiation in plumage and in call. All true ducks, except those in the shelduck (q.v.) group and sea ducks, mature in the first year and pair only for the seasonunlike the late-maturing, life-mating true geese and swans. They are generally divided into three major groups, dabbling, diving, and perching ducks, based on their characteristic behaviours. The mallard (q.v.), a typical dabbling duck, is one of the most popular game birds and is the ancestor of most domestic ducks (see fowl). Perching ducks such as the muscovies have long claws and are the most arboreal of ducks, often roosting in trees. The diving ducks include the greatest number of marine species, such as the eider and the scoter (qq.v.), but also include the merganser (q.v.) group, most of which prefer freshwater areas. Members of the stifftail (q.v.) group, typified by the ruddy duck, are highly aquatic ducks, characterized by legs set far toward the rear of the body. The whistling duck (q.v.) species, also called tree ducks, are not true ducks but are more closely related to the geese and swans. See also dabbling duck; diving duck; perching duck.