Duck
I |
Duck, name collectively applied to numerous species of a family of waterfowl. Ducks differ from geese (see goose) and swans of the same family by their shorter necks and legs, and other anatomical features. They inhabit all continents except Antarctica , and some of the world’s islands. The legs of most ducks are placed far apart and towards the rear, making them clumsy walkers but efficient swimmers. The underplumage (down), which is buoyant and insulating, is kept water-resistant by frequent preening with oil from the uropygial, or preen, gland at the base of the tail feathers. Ducks, with the exception of mergansers, have spatulate bills lined with bony notches, or lamellae, for straining plant and animal matter from water.
Some island species have lost the power of flight, but most ducks of northern continents are highly migratory. In a few species, the sexes are alike in colour, but in most the males (drakes) are brighter and more boldly patterned.
II | COURTSHIP AND REPRODUCTION |
Ducks have elaborate courtship displays, each unique to its species. Pair formation in most Northern-hemisphere ducks takes place in winter; hence—unlike most birds with seasonal plumage—males wear their bright plumage in winter, and briefly assume a female-like “eclipse” plumage during the summer. Nests of most species are on the ground, containing from 4 to 12 eggs, surrounded by down feathers plucked from the female’s breast and belly. Ducklings are able to swim and feed themselves soon after they hatch. Some species, such as the wood duck of North America , nest in holes in trees and will make use of artificial nest boxes. Their ducklings can jump from the nests without injury, and take to the water soon afterwards. They learn to fly in five to eight weeks.
III | MIGRATION |
Distances covered by migrating ducks vary with the species. One Arctic duck, the spectacled eider, winters at sea off Alaska . Long-distance champion among European ducks is the garganey, which nests in most of northern Europe and winters in tropical Africa .
IV | TYPES OF DUCKS |
Experts disagree about the classification of ducks into subfamilies and tribes, but the hundred or so species include a number of obvious groups. Most familiar are the dabbling or surface-feeding ducks, which include the mallard, ancestor of most domestic ducks. Members of this group live primarily on fresh water, where they glean plants and small aquatic animals from the surface or from the bottoms of shallow waters that they can reach without diving. The pochards, including the canvasback, nest by fresh water, but winter—often in very large flocks—on inland lakes and along the coasts; they feed by diving. Another group of diving ducks, including the goldeneyes and the bufflehead, nest in holes in trees. The mergansers are specialized for catching fish; the edges of their bills have sharp, tooth-like serrations for holding slippery prey. Of the European ducks the most marine are the eiders and scoters, which nest in the far north and winter predominantly at sea.
V | DOMESTIC DUCKS |
All except one breed of domestic duck are derived from the mallard, originally tamed in Eurasia . The exception is the muscovy duck, a large species of the American tropics. Wild muscovies are mostly black, but the commonest domestic variety is white, with knobby, naked red skin around the face and bill. It and the turkey are the only domestic birds that originated in the Americas .
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