Zookeepers Finally Solve Mystery Of Female Monkey Who Got Pregnant While Alone In Her Cage

Zookeepers have finally cracked the puzzling case of how a female monkey became pregnant despite living in complete isolation in her cage.

Momo, a 12-year-old white-handed gibbon, was reportedly kept alone in her enclosure with no known access to a male of her species.

The unexpected pregnancy, first discovered in 2021 at the Kujukushima Zoo and Botanical Garden in Nagasaki, left staff scratching their heads.

Initially, zoo officials were at a loss.

On social media, they admitted they had no idea who the father was and explained that DNA testing couldn’t be done immediately because Momo was fiercely protective of her newborn.

A post from the zoo read: “Just so everyone wants to know ‘who’s the dad’ hasn’t been found out yet because we haven’t done DNA testing, but we found out the gender is male.”

Years later, the mystery was finally unraveled.

Zookeepers have finally cracked the puzzling case of how an isolated female gibbon named Momo became pregnant. Credit: Kujukushima Zoo and Botanical Garden
The zoo’s superintendent, Jun Yamano, explained the long delay: “It took us two years to figure it out because we couldn’t get close enough to collect samples – she was very protective of her child.”

When DNA testing was eventually completed, the results pointed to a surprising father: a 34-year-old male gibbon named Itō, housed in a neighboring enclosure.

But how did Momo and Itō manage to mate if they were kept in separate cages?

As it turns out, the answer lay in a seemingly insignificant detail.
An update on the male baby gibbon revealed he is ‘growing healthily.’ Credit: Kujukushima Zoo and Botanical Garden
Zoo staff uncovered a tiny, nine-millimeter hole in the steel plate that divided their enclosures during the investigation, CNN reports.

While neither zoo personnel nor surveillance captured any mating activity, they now believe that Momo and Itō found a way to engage through this gap when they were rotated into adjacent display areas.

Yamano told Vice that such an event was unprecedented at their facility, as the zoo typically introduces gibbons to each other in a controlled and intentional setting.

Following the revelation, the zoo has since repaired the hole and plans to allow Momo, Itō, and their baby to share the same enclosure going forward.

According to Hideki Hisano, the zoo’s deputy director, the male baby reportedly continued ‘growing healthily.’

“It is a precious life born into the world, we will continue to take good care of him and hope that he will live a healthy long life,” Hisano said.

Gibbons, known for their agile movements and loud, complex vocalizations, are native to Asia and are classified as endangered, largely due to habitat destruction.