Mallard

The mallard is a medium-large waterfowl species that is heavier than most other dabbling ducks. It is 50–65 cm (20–26 in) long, of which the body makes up around two-thirds, and has a wingspan of 81–98 cm (32–39 in); it weighs 0.7–1.6 kg (1.5–3.5 lb). Among standard measurements, the wing chord is 25.7 to 30.6 cm (10.1 to 12.0 in), the bill is 4.4 to 6.1 cm (1.7 to 2.4 in), and the tarsus is 4.1 to 4.8 cm (1.6 to 1.9 in).The breeding male mallard is unmistakable, with a glossy bottle-green head and a white collar that demarcates the head and neck from the purple-tinged brown breast, grey-brown wings, and a pale grey belly. The rear of the male is black, with white-bordered dark tail feathers. The bill of the male is a yellowish-orange tipped with black, with that of the female generally darker and ranging from black to mottled orange and brown. The female mallard is predominantly mottled, with each individual feather showing sharp contrast from buff to very dark brown, a coloration shared by most female dabbling ducks, and has buff cheeks, eyebrow, throat, and neck, with a darker crown and eye-stripe. Mallards, like other sexually-dimorphic birds, can sometimes go through spontaneous sex reversal, often caused by damaged or nonfunctioning sex organs, such as the ovaries. …

The mallard is widely distributed across the Northern and Southern Hemispheres; in North America its range extends from southern and central Alaska to Mexico, the Hawaiian Islands, across the Palearctic, from Iceland and southern Greenland and parts of Morocco (North Africa) in the west, Scandinavia and Britain to the north, and to Siberia, Japan, and South Korea. Also in the east, it ranges to south-eastern and south-western Australia and New Zealand in the Southern Hemisphere. It is strongly migratory in the northern parts of its breeding range, and winters farther south. For example, in North America, it winters south to the southern United States and northern Mexico, but also regularly strays into Central America and the Caribbean between September and May. A drake later named "Trevor" attracted media attention in 2018 when it turned up on the island of Niue, an atypical location for mallards. The mallard inhabits a wide range of habitats and climates, from the Arctic tundra to subtropical regions. It is found in both fresh- and salt-water wetlands, including parks, small ponds, rivers, lakes and estuaries, as well as shallow inlets and open sea within sight of the coastline. Water depths of less than 0.9 metres (3.0 ft) are preferred, with birds avoiding areas more than a few metres deep. They are attracted to bodies of water with aquatic vegetation.

The mallard is omnivorous and very flexible in its choice of food. Its diet may vary based on several factors, including the stage of the breeding cycle, short-term variations in available food, nutrient availability, and interspecific and intraspecific competition. The majority of the mallard's diet seems to be made up of gastropods, insects (including beetles, flies, lepidopterans, dragonflies, and caddisflies), crustaceans, other arthropods, worms, feces of other birds, many varieties of seeds and plant matter, and roots and tubers. During the breeding season, male birds were recorded to have eaten 37.6% animal matter and 62.4% plant matter, most notably the grass Echinochloa crus-galli, and nonlaying females ate 37.0% animal matter and 63.0% plant matter, while laying females ate 71.9% animal matter and only 28.1% plant matter. Plants generally make up the larger part of a bird's diet, especially during autumn migration and in the winter. The mallard usually feeds by dabbling for plant food or grazing; there are reports of it eating frogs, other amphibians, and fish, including carcasses. However, in 2017 a flock of mallards in Romania were observed hunting fledglings of small migratory birds when they land in the water, which included a grey wagtail and a black redstart. This was the first documented occasion they had been seen attacking and consuming large vertebrates. …

The mallard has been eaten as food since ancient times, with evidence they were eaten in Neolithic Greece. Usually, only the breast and thigh meat is eaten. It does not need to be hung before preparation, and is often braised or roasted, sometimes flavoured with bitter orange or with port.

The mallard was one of the many bird species originally described in the 1758 10th edition of Systema Naturae by Carl Linnaeus. He gave it two binomial names: Anas platyrhynchos and Anas boschas. The latter was generally preferred until 1906 when Einar Lönnberg established that A. platyrhynchos had priority, as it appeared on an earlier page in the text. The scientific name comes from Latin Anas, "duck" and Ancient Greek πλατυρυγχος, platyrhynchus, "broad-billed" (from πλατύς, platys, "broad" and ρυγχός, rhunkhos, "bill"). The genome of Anas platyrhynchos was sequenced in 2013. The name mallard originally referred to any wild drake, and it is sometimes still used this way. It was derived from the Old French malart or mallart for "wild drake" although its true derivation is unclear. It may be related to, or at least influenced by, an Old High German masculine proper name Madelhart, clues lying in the alternative English forms "maudelard" and "mawdelard". Masle (male) has also been proposed as an influence. Mallards frequently interbreed with their closest relatives in the genus Anas, such as the American black duck, and also with species more distantly related, such as the northern pintail, leading to various hybrids that may be fully fertile. …