duck, common name for wild and domestic waterfowl of the family Anatidae, which also includes geese and swans. It is hunted and bred for its meat, eggs, and feathers. Strictly speaking, duck refers to the female and drake to the male. Ducks are usually divided into three groups: the surface-feeding ducks—such as the mallard, wood duck, black duck, and teal—which frequent ponds, marshes, and other quiet waters; the diving ducks—such as the canvasback, scaup, scoter, eider, and redhead—found on bays, rivers, and lakes; and the fish-eating ducks, the mergansers, with slender, serrated bills, which also prefer open water. The surface feeders take wing straight up, while the divers patter along the water's surface in taking off. Ducks make long migratory flights. At the time of the postnuptial molt, the power of flight is temporarily lost, and most of the Northern Hemisphere drakes assume "eclipse" plumage similar to that of the female. The ancestor of all domestic breeds (see poultry), except the Muscovy of South American origin, is the mallard, Anas boscas, which is found in Europe, Asia, and North America. In the mallard drake a white ring separates the bright-green head and neck from the chestnut breast, the back is grayish brown, the tail white, and the wings have blue patches. The wood duck, Aix sponsa, smaller than the mallard, nests in hollow trees; the drake is a varicolored, iridescent ornament to lakes and ponds. The blue-winged, green-winged, and European teals (genus Querquedula) are small ducks that fly with great speed. The canvasback, Fuligula vallisneria, is hunted widely for its palatable flesh. It has a chestnut head and neck, black bill and chest, and whitish back and underparts. A swift flier, it is also an expert swimmer and diver. It breeds from the Dakotas and Minnesota north and winters on the coastal waters along the entire continent. In northern countries a portion of the down with which the eider ducks line their nests is systematically collected, as are some of the eggs; since the eiders lay throughout the season, these are soon replaced. The mergansers, genus Mergus, also called sheldrakes or sawbills, are usually crested. They include the goosander and the smaller red-breasted merganser, both circumpolar in distribution, and the North American hooded merganser, similar to the Old World smew. Because their fish diet gives their flesh a rank taste, they are called by sportsmen "trash ducks." Ducks are classified in the phylum Chordata, subphylum Vertebrata, class Aves, order Anseriformes, family Anatidae.

North American duck (Aix sponsa, family Anatidae); a popular game bird. Wood ducks, 17–21 in. (43–52 cm) long, nest in a tree cavity up to 50 ft (15 m) off the ground; they have long-clawed toes for perching. Both sexes have a head crest in winter. The beautifully coloured male has a purple and green head, red-brown breast flecked with white, and bronze sides; the female has a white eye ring and duller colouring. Ducklings eat aquatic insects and other small organisms; adults prefer acorns or other nuts. Hunted nearly to extinction for its flesh and feathers, it has been restored to healthy populations by strong conservation efforts.

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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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or duckbill

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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or duck hawk

Falcon species (Falco peregrinus) found worldwide but rare today because of bioaccumulation of pesticides. Peregrines are 13–19 in. (33–48 cm) long and gray above, with black-barred whitish underparts. They fly high and dive at tremendous speed (up to 175 mph, or 280 kph—the greatest speeds attained by any bird), striking with clenched talons and killing by impact. They usually nest in a scrape on a high cliff ledge near water, where bird prey is plentiful. Breeding programs have reintroduced the species into the wild and introduced it into urban areas, where it finds a clifflike habitat among skyscrapers and preys chiefly on the rock dove (see pigeon). Despite the programs' success, the species remains vulnerable.

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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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Any of about 43 species (tribe Anatini; including 38 species in genus Anas) of ducks found worldwide, chiefly on inland waters and most commonly in temperate regions of the Northern Hemisphere. Strongly migratory, dabbling ducks include some of the world's finest game birds: the black duck, the gadwall, the garganey, the mallard, the pintail (perhaps the world's most abundant waterfowl), the shoveler, the teals, and the wigeons. They feed mainly on water plants, which they obtain by tipping-up in shallows and infrequently by diving. They often forage near the shore for seeds and insects. They have a flat, broad bill, float high in the water, and are swift fliers. Males are slightly larger and more boldly coloured than females.

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For duck as a food, see Duck (food); for other meanings, see Duck (disambiguation).

Duck is the common name for a number of species in the Anatidae family of birds. The ducks are divided between several subfamilies listed in full in the Anatidae article. They do not represent a monophyletic group, but are instead the members of the family not otherwise considered swans and geese. Ducks are mostly aquatic birds, mostly smaller than the swans and geese, and may be found in both fresh water and sea water.

Ducks are sometimes confused with several types of unrelated water birds with similar forms, such as loons or divers, grebes, gallinules, and coots.

Etymology

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".

Morphology

The overall body plan of ducks is elongated and broad, and the ducks are also relatively long-necked, albeit not as long-necked as the geese and swans. The body shape of diving ducks varies somewhat from this in being more rounded. The bill is usually broad and contains serrated lamellae] which are particularly well defined in the filter-feeding species. In the case of some fishing species the bill is long and strongly serrated. The scaled legs are strong and well developed, and generally set far back on the body, more so in the highly aquatic species. The wings are very strong and are generally short and pointed, and the flight of ducks requires fast continuous strokes, requiring in turn strong wing muscles. Three species of steamer duck are almost flightless however. Many species of duck are temporarily flightless while moulting; they seek out protected habitat with good food supplies during this period. This moult typically precedes migration.

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.

Behaviour

Feeding

Ducks exploit a variety of food sources such as grasses, aquatic plants, fish, insects, small amphibians, worms, and small molluscs.

Diving ducks and sea ducks forage deep underwater. To be able to submerge more easily, the diving ducks are heavier than dabbling ducks, and therefore have more difficulty taking off to fly.

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 few specialized species such as the smew, goosander, and the mergansers are adapted to catch and swallow large fish.

Breeding

The ducks are generally monogamous, although these bonds generally last a single year only. Larger species and the more sedentary species (like fast river specialists) tend to have pair-bonds that last numerous years. Most duck species breed once a year, choosing to do so in favourable conditions (spring/summer or wet seasons).

Communication

Despite widespread misconceptions, most ducks other than female Mallards and domestic ducks do not "quack"; for example, the scaup makes a noise like "scaup", which its name came from. The ducks make a wide range of calls, ranging from whistles cooing, yodels and grunts. Calls may be loud displaying calls or quieter contact calls.

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.

Ecology

Distribution and habitat

The ducks have a cosmopolitan distribution occurring across most of the world except for Antarctica. A number of species manage to live on sub-Antarctic islands like South Georgia and the Auckland Islands. Numerous ducks have managed to establish themselves on oceanic islands such as Hawaii, New Zealand and Kerguelen, although many of these species and populations are threatened or have become extinct.

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.

Predators

Worldwide, ducks have many predators. Ducklings are particularly vulnerable, since their inability to fly makes them easy prey not only for avian hunters but also large fish like pike, crocodilians, and other aquatic hunters, including fish-eating birds such as herons. Ducks' nests are raided by land-based predators, and brooding females may be caught unaware on the nest by mammals such as foxes, or large birds, such as hawks or eagles.

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.

Relationship with humans

Culinary

As food, "duck" refers to the meat of several species of bird in the Anatidae family, found in fresh or salt water. Duck is eaten around the world.

Domestication

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.

FAO reports that China is the top duck market in 2004 followed by Vietnam and other South East Asian countries.

Hunting

In many areas, wild ducks of various species (including ducks farmed and released into the wild) are hunted for food or sport, by shooting, or formerly by decoys. Because an idle, floating duck or a duck squatted on land cannot react to fly or to move quickly, "a sitting duck" has come to mean "an easy target".

Cultural references

In 2002, psychologist Richard Wiseman and colleagues at the University of Hertfordshire, UK]]) finished a year-long LaughLab experiment, concluding that of all animals, ducks attract most the humor and silliness; he said "If you're going to tell a joke involving an animal, make it a duck." The word "duck" may have become an inherently funny word in many languages possibly because ducks are seen as silly in their looks or behavior. Of the many ducks in fiction, many are cartoon characters like Daffy Duck (see the New Scientist article mentioning humor in the word "duck").

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.

Gallery

See also

• Domesticated duck — ducks kept as pets or show animals and for meat and eggs and down
• List of fictional ducks
• Waterfowl hunting

References

External links

• Wild Ducks Info – More info regarding the wild ducks.
• Duck videos on the Internet Bird Collection
• list of books (useful looking abstracts)
• - A modern illustrated guide to identification of US waterfowl.
• Duck necrophilia Necrophilia among ducks ruffles research feathers