Drake wood duck (Aix sponsa)
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Abundant “wild duck” (Anas platyrhynchos, family Anatidae) of the Northern Hemisphere, ancestor of most domestic ducks. The mallard is a typical dabbling duck in its general habits and courtship display. The drake of the common mallard (subspecies A. p. platyrhynchos) has a metallic green or purplish head, reddish breast, and light-gray body; the hen is mottled yellowish brown. Both sexes have a yellow bill and a purplish blue, white-bordered wing mark. Males and females of the Greenland mallard (A. p. conboschas) also differ markedly in plumage. In the other subspecies, both sexes resemble the female common mallard. Mallards are found throughout most of Asia, Europe, and northern North America.
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Monotreme amphibious mammal (Ornithorhynchus anatinus) of lakes and streams in eastern Australia and Tasmania. About 23 in. (60 cm) long, the squat-bodied platypus has a ducklike snout, short legs, webbed feet, and a beaverlike tail. Each day it eats nearly its own weight in crustaceans, fishes, frogs, mollusks, tadpoles, and earthworms; lacking teeth, it crushes its food with ridges in the bill. The female lays one to three eggs in a nest in a long twisting passage above the waterline. The young are weaned about four months after hatching. The male's heel bears a spur connected to a poison-secreting gland. Large fishes and perhaps snakes prey on platypuses. Formerly trapped for their dense, soft fur, they are now protected by law.
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Peregrine falcon (Falco peregrinus).
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Any of various relatively small, short-necked, large-billed waterfowl (several genera in subfamily Anatinae, family Anatidae). The legs of true ducks (Anatinae) are placed rearward (as are those of swans), resulting in a waddling gait. Most true ducks differ from swans and true geese (see goose) in that male ducks 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 differences between sexes in plumage and in call. All true ducks except shelducks and sea ducks (see diving duck) mature in the first year and pair only for the season. They are generally divided into three groups: perching ducks, dabbling ducks, and diving ducks. The whistling duck species, also called tree ducks, are not true ducks but are more closely related to geese and swans.
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Any duck that obtains its food by diving to the bottom in deep water rather than by dabbling in shallows (see dabbling duck). Diving ducks prefer marine environments and are popularly called either bay ducks or sea ducks. Bay ducks (tribe Aythyini, family Anatidae), including canvasback, redhead, scaup, and allied species, are found more frequently in estuaries and tidal lagoons than on the open sea. Sea ducks (20 species in tribes Mergini and Somateriini) include the bufflehead, eiders, goldeneye, mergansers, oldsquaw, and scoters; some are also or mainly found on inland waters.
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Common, or northern, pintail (Anas acuta).
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The word duck (from Anglo-Saxon dūce), meaning the bird, came from the verb "to duck" (from Anglo-Saxon supposed *dūcan) meaning "to bend down low as if to get under something" or "to dive", because of the way many species in the dabbling duck group feed by upending (compare Dutch duiken, German tauchen = "to dive").
This happened because the older Anglo-Saxon words ened (= "duck") and ende (= "end") came to be pronounced the same: other Germanic languages still have similar words for "duck" and "end": for example, Dutch eend = "duck", eind = "end", German Ente = "duck", Ende = "end"; this similarity goes back to Indo-European: compare Latin anas (stem anat-) = "duck", Lithuanian antis = "duck", Ancient Greek νησσα, νηττα (nēssa, nētta) = "duck"; Sanskrit anta = "end".
Some people use "duck" specifically for adult females and "drake" for adult males, for the species described here; others use "hen" and "drake", respectively.
A duckling is a young duck in downy plumage or baby duck.; but in the food trade young adult ducks ready for roasting are sometimes labelled "duckling".
The drakes of northern species often have extravagant plumage, but that is moulted in summer to give a more female-like appearance, the "eclipse" plumage. Southern resident species typically show less sexual dimorphism, although there are exceptions like the Paradise Shelduck of New Zealand which is both strikingly sexually dimorphic and where the female's plumage is brighter than that of the male. The plumage of juvenile birds generally resembles that of the female.
Dabbling ducks feed on the surface of water or on land, or as deep as they can reach by up-ending without completely submerging. Along the inside of the beak they have tiny rows of plates called lamellae like a whale's baleen. These let them filter water out of the side of their beaks and keep food inside.
A common urban legend claims that duck quacks do not echo; however, this has been shown to be false. This myth was first debunked by the Acoustics Research Centre at the University of Salford in 2003 as part of the British Association's Festival of Science. It was also debunked in one of the earlier episodes of the popular Discovery Channel television show MythBusters.
Some duck species, mainly those breeding in the temperate and Arctic Northern Hemisphere, are migratory; those in the tropics, however, are generally not. Some ducks, particularly in Australia where rainfall is patchy and erratic, are nomadic, seeking out the temporary lakes and pools that form after localised heavy rain.
Ducks have become an accepted presence in populated areas. Migration patterns have changed such that many species remain in an area during the winter months. In spring and early summer ducks sometimes influence human activity through their nesting; sometimes a duck pair nests well away from water, needing a long trek to water for the hatchlings: this sometimes causes an urgent wildlife rescue operation (e.g. by the RSPCA) if the duck nested somewhere unsuitable like in a small enclosed courtyard.
Adult ducks are fast fliers, but may be caught on the water by large aquatic predators. This can includes fish such as the North American muskie and the European pike. In flight, ducks are safe from all but a few predators such as humans and the Peregrine Falcon, which regularly uses its speed and strength to catch ducks.
Ducks have many economic uses, being farmed for their meat, eggs, feathers, (particularly their down). They are also kept and bred by aviculturists and often displayed in zoos. All domestic ducks are descended from the wild Mallard Anas platyrhynchos, except the Muscovy Duck . Many domestic breeds have become much larger than their wild ancestor, with a "hull length" (from base of neck to base of tail) of 30 cm (12 inches) or more and routinely able to swallow an adult British Common Frog Rana temporaria whole.
A duck test is a form of inductive reasoning, which can be phrased as follows: "If a bird looks like a duck, swims like a duck and quacks like a duck, then it probably is a duck." The test implies that a person can figure out the true nature of an unknown subject by observing this subject's readily identifiable traits. It is sometimes used to counter abstruse arguments that something is not what it appears to be.