Duck

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

Ducks
Bufflehead
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Anseriformes
Family:	Anatidae
Subfamilies
Dendrocygninae Oxyurinae Anatinae Aythyinae Merginae

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

Portrait of a female mallard duck

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".

Mallard ducklings.

File:Spottedduck001.JPG

A spotted duck.

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

Ducks have been known to perform duck-like acts in places such as rivers, ponds or lakes, so if you do come across a duck in such a location, do not be alarmed. On rare occasions, ducks may or may not perform armed robberies at their local banks. If you should happen to see a duck robbery in process, I urge you to call the national Criminal Duck Helpline on 0800 600 800. Thank you.

Feeding

Lamellae along the beak.

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

File:DSCF4687b.jpg

A Duck and her Ducklings, in a canal in Loughborough

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

Main article: Duck (food)

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

File:2004duck.PNG

Duck headcount in 2004

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 [1] 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

• 
  African Comb Duck
• 
  Mallard drake
• 
  Male Wood Duck in eclipse plumage
• Male Muscovy Duck
  Male Muscovy Duck
• 
  Male Mandarin Duck
• 
  Ringed Teal
• 
  Red-crested Pochard
• 
  A male Mallard flying.

See also

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

External links

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