For the first time in the 70-year history of the Takasakiyama Natural Zoological Garden in the Japanese island of Kyushu, a female macaque had risen to be the alpha female of a 677-strong troop of macaque monkeys.
Yakei, a 9-year-old macaque, got her start when she beat up her own mother in April. Two months later, she overthrew the reigning alpha male, a 31-year old male macaque named Sanchu who had been leader of the macaque troop for five years.
The surprised wardens at the nature reserve decided to confirm Yakei’s rise to power by conducting a “peanut test”. They put out peanuts for the macaque troop to eat and watched who ate first. Sanchu yielded to Yakei, giving her the first dibs on the treats thus confirming her alpha female status.
In an interview with The Guardian, nature reserve guide Satoshi Kimoto said:
“Since then, Yakei has been climbing trees and shaking them, which is an expression of power and a very rare behaviour in females … She has been walking around with her tail up, which is also very unusual for a female.”
Male macaque monkeys tend to be more aggressive, thus explaining why they tended to dominate the competition to become alpha. Eye contact signals a challenge, so visitors to the reserve are advised not to stare at the monkeys.
Takasakiyama was established as a home to 1,500 macaques in 1952. The forested mountain in the center of the reserve gave them freedom to roam and climb. Today, there are more than 100,000 wild macaques in Japan, spread across the islands of Kyushu, Honshu, and Shikoku.
Image credit: Takasakiyama Natural Zoological Garden