The mandarin duck (Aix galericulata) is a perching duck species native to the East Palearctic. It is medium-sized, at long with a wingspan. It is closely related to the North American wood duck, the only other member of the genus Aix. is an Ancient Greek word which was used by Aristotle to refer to an unknown diving bird, and is the Latin for a wig, derived from , a cap or bonnet. Outside of its native range, the mandarin duck has a large introduced population in the British Isles and Western Europe, with additional smaller introductions in North America. Description The adult male has a red bill, large white crescent above the eye and reddish face and "whiskers". The male's breast is purple with two vertical white bars, the flanks ruddy, and he has two orange feathers at the back (large feathers that stick up similar to boat sails). The female is similar to the 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. Both the males and females have crests, but the purple crest is more pronounced on the male. Like many other species of ducks, the male undergoes a moult after the mating season into eclipse plumage. When in eclipse plumage, the male looks similar to the female, but can be told apart by its bright yellow-orange or red beak, lack of any crest, and a less-pronounced eye-stripe. Mandarin ducklings are almost identical in appearance to wood ducklings, and 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. Mutations Various mutations of the mandarin duck are found in captivity. The most common is the white mandarin duck. Although the origin of this mutation is unknown, the constant pairing of related birds and selective breeding is presumed to have led to recessive gene combinations, leading in turn to genetic conditions including leucism. Distribution and habitat 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