The Mandarin duck (Aix galericulata), or just Mandarin, is a perching duck species found in East Asia. It is medium-sized, at 41–49 cm long with a 65–75 cm wingspan. As the other member of the genus Aix, it is closely related to the North American wood duck.
The adult male is a striking and unmistakable bird. It has a red bill, large white crescent above the eye and reddish face and "whiskers". The breast is purple with two vertical white bars, and the flanks ruddy, with two orange "sails" at the back. The female is similar to female wood duck, with a white eye-ring and stripe running back from the eye, but is paler below, has a small white flank stripe, and a pale tip to its bill.
Mandarin ducklings are almost identical in look to wood ducklings, and appear very similar to mallard ducklings. The ducklings can be distinguished from mallard ducklings because the eye-stripe of Mandarin ducklings (and wood ducklings) stops at the eye, while in mallard ducklings it reaches all the way to the bill.
The species was once widespread in East Asia, but large-scale exports and the destruction of its forest habitat have reduced populations in eastern Russia and in China to below 1,000 pairs in each country; Japan, however, is thought to still hold some 5,000 pairs. The Asian populations are migratory, overwintering in lowland eastern China and southern Japan.
Specimens frequently escape from collections, and in the 20th century a large feral population was established in Great Britain; more recently small numbers have bred in Ireland, concentrated in the parks of Dublin. There are now about 7,000 in Britain, and other populations on the European continent, the largest in the region of Berlin. Isolated populations exist in the United States. The town of Black Mountain, North Carolina has a limited population, and there is a free-flying feral population of several hundred mandarins in Sonoma County, California. This population is the result of several Mandarin ducks escaping from captivity, then going on to reproduce in the wild.
In the wild, Mandarin ducks breed in densely wooded areas near shallow lakes, marshes or ponds. They nest in cavities in trees close to water and during the spring, the females lay their eggs in the tree's cavity after mating. A single clutch of nine to twelve eggs is laid in April or May. Although the male may defend the brooding female and his eggs during incubation, he himself does not incubate the eggs and leaves before they hatch. Shortly after the ducklings hatch, their mother flies to the ground and coaxes the ducklings to leap from the nest. After all of the ducklings are out of the tree, they will follow their mother to a nearby body of water.
