Japan Zoo Discovers Male Resident Hippo Is Actually a Female After 7 Years

"We recognize the importance of reconfirming the sex of introduced animals, and will take precautions to ensure that this does not happen again," said the zoo

A zoo in Japan has learned a new critical detail about one of its resident hippos — its sex.

The Osaka Tennoji Zoo revealed on its website that Gen-chan, a hippo taken in as a male from Mexico's Africam Safari in 2017 at age 5, is actually a female.

According to the zoo, Mexican zoo officials told them Gen-chan was a male when they took him in, and "the documents required for import also indicated that it was a male."

While they initially had "no doubts" about Gen-chan's sex, they recalled noticing that the animal never displayed "male-specific behaviors" as it grew older.

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According to the San Diego Zoo Wildlife Alliance Library's website, typical behaviors of male hippos include "jaw-to-jaw sparring and yawning contests at adolescence" and being "territorial" in water.

Being that Gen-chan's reproductive organs are also not able to be "visually confirmed," the zoo opted for Gen-chan to undergo DNA testing by an outside institution.

"Based on this result, we recognize the importance of reconfirming the sex of introduced animals, and will take precautions to ensure that this does not happen again. We will continue to strive to provide a comfortable environment for Gen-chan, so we hope that you will continue to come and see Gen-chan," the zoo added.

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On the other side of the world, another beloved zoo also recently announced news about one of its resident hippos.

"We have some very sad and difficult news to share," Seattle's Woodland Park Zoo announced in a post on its website on Wednesday, April 24.

"We will soon say goodbye to our beloved hippopotamus Water Lily, who has experienced declining health and quality of life following a cancer diagnosis last month. Veterinarians and caretakers have made a difficult end-of-life decision for the 45-year-old hippo, affectionately known as Lily, who will be humanely euthanized early next week," the zoo wrote.

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Local community residents can visit the beloved mammal until Sunday, April 28, "after which time the pathway will be temporarily closed."

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