The Mandarin Duck (Aix galericulata) is a perching duck species found in East Asia. It is medium-sized, at 41–49 cm (16–19 in) long with a 65–75 cm (26–30 in) wingspan. It is closely related to the North American wood duck, the only other member of the genus Aix. Aix is an Ancient Greek word used by Aristotle to refer to an unknown diving bird, and galericulata is the Latin for a wig, derived from galerum, a cap or bonnet.
The Mandarin duck breeds in eastern Siberia, China, and Japan and winters in southern China and Japan. There is a small free-flying population in Britain stemming from the release captive bred ducks.
The Mandarin lives in the forests of China and Japan. They prefer wooded ponds and fast flowing rocky streams to swim, wade, and feed in.
In full plumage, the male has a pair of "sail" feathers that are raised vertically above the back, a crest of orange and cream feathers, and a broad white eye-stripe that is bounded above and below by darker feathers. The female is duller in color and has an overall grey appearance marked by a curving white stripe behind the eye and a series of white blotches on the underparts. In flight, both sexes display a bluish-green iridescent speculum.
Mandarin courtship display is very impressive and includes mock-drinking and shaking. Pairs are formed at the beginning of the winter and may continue for many seasons. Although the female chooses the exact nesting site, the male accompanies the female on nest searches. Nest are alway in a hole in a tree and can be up to thirty feet from the ground. In preparation for egg laying, the female lines the nest is with down. Clutch sizes range from nine to twelve white oval eggs that are laid at daily intervals. Incubation is solely performed by the female and last between 28 and 30 days. When all the eggs are hatched (they hatch within a few hours of each other), the mother calls to the chicks from the ground. Each chick then crawls out of the hole and launches itself into a free fall. Amazingly, all the chicks land unhurt and are en route to the nearest feeding ground. Once the chicks are able to fly (after 40-45 days), they leave to join a new flock.
Justification (IUCN Red List)
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.