Have you ever heard the term "Mandarin Duck couple"?

The term "Mandarin Duck couple" refers to a happily married couple, but you may have heard that many Mandarin Duck change partners every year, so in reality, they are not really a "Mandarin Duck couple" at all.

During the breeding season, from around November to March, male wild Mandarin Duck ducks molt from the same brownish plumage as the females into their familiar colorful "breeding plumage." Breeding plumage often features bright colors and patterns, serving to attract females.


A male (right) whose feathers have been replaced with breeding feathers.
On the other hand, Mandarin Duck in zoos tend to molt into their breeding plumage a little earlier than wild Mandarin Duck, perhaps due to better nutrition. Mandarin Duck ducks at Inokashira Park Zoo 's aquatic life area also began molting around mid-August last year.

Normally, male birds that have molted into their breeding plumage will try to attract females by making low "gugugu" sounds or sticking out their chests, but the male featured here didn't bother with such leisurely actions.

On the morning of August 30, 2023, we discovered a male mandarin duck, whose feathers had not yet been replaced by breeding plumage by 70%, already paired with a female and moving around together. It was previously thought that Mandarin Duck ducks attracted females and found mates with their flashy appearance during the breeding season, but this was a new discovery suggesting that appearance may not be everything.

As a follow-up, the female of this pair never entered the nest box, and naturally, she never laid any eggs. When the breeding season ended, the two birds separated as if they had been given the command to "disperse!", and went their separate ways as if nothing had happened. What does this mean? Both birds are quite old, over 10 years old. Perhaps they paired up early so that they could spend their time peacefully without being caught up in the activities of other males and females during the breeding season? Only the two birds know the truth...

And then, coincidentally, on August 30th of this year, 2024, the two birds had paired up again, even though the male hadn't even grown his breeding plumage yet!


Mandarin Duck quickly formed a pair before their breeding plumage was fully developed (left: female, right: male).
Although they didn't breed last year, it's remarkable that these two found the same mates as last year before the other Mandarin Duck started moving around, and paired up at the same early stage as last year.

This pair might just be the epitome of a true "Mandarin Duck couple."

[Inokashira Park Zoo Aquatic Life House]

◎Related articles
・ Mandarin Duck (December 1, 2006)
・ The ducks have begun to change their coats. (September 23, 2011)

(October 3, 2024)