When we talk about changing clothes around this time of year, it's about switching from summer clothes to autumn and winter clothes. It's still quite hot, so we can't put away short sleeves anytime soon, but the ducks being raised at Inokashira Park Zoo branch are making progress with their change of clothes.

However, they don't wear clothes like humans do. Their feathers are replaced through a process called "molting." Females hardly change their markings between summer and winter plumage, but males are considerably larger, and some species show significant changes in color and design.

Among them, the mandarin duck stands Mandarin Duck. The Mandarin Duck duck, often seen in field guides, has very colorful feathers all over its body, and its orange, fan-shaped feathers, in particular, resemble the shape of a ginkgo leaf and are therefore called "ginkgo feathers." This is seasonal and can only be seen during the breeding season; at other times of the year, the male has the same plain grayish-brown plumage as the female.
The male birds in the exhibit had rather plain plumage until recently, but since early September, they have gradually started to grow colorful feathers.

In addition, the male Mallard have begun to develop a glossy deep green color from their heads to their necks. This deep green can appear ultramarine depending on the angle. A white ring has also appeared at the border between their neck and chest, and their chests are brown, giving them a striking coloration, though not as striking as that of Mandarin Duck ducks.

Molting varies in timing depending on the species and individual, but it is mostly finished by November, and there will be more colorful male ducks than females. Please come and see them!

Top photo: (left) Mandarin Duck duck that has molted with colorful feathers, and (right) a male with still plain plumage.
Photo below: (left) a Mallard with dark green feathers and (right) a male mallard molting.

[Misaki Kawate, Animal Care and Exhibition Staff, Inokashira Park Zoo Aquatic Life House]

(September 23, 2011)