Two young Bornean orangutan siblings in a Hokkaido zoo have started sharing a home in a rare attempt to have the brother bring up his younger sister following their mother's death.

Morito, 11, and his sister Moka, 4, began living together in Asahiyama Zoo from late May, and can be seen playing chase and sharing bananas.

Orangutans usually live independently after being raised by their mothers up until the age of 6 to 9, according to the zoo. Moka had been looked after by her mother Liang, until Liang died suddenly in March of a subarachnoid hemorrhage.

For two months after Liang's death, Moka was raised alone. But zoo keeper Tomohiro Sahashi, 35, said he worried about her, especially thinking ahead to when she becomes a mother herself.

[Video by The Hokkaido Shimbun Press]

"With only the memory of being parented until 4 years old, she might abandon her child, not knowing how to take care of it," he said.

Then the zoo keepers came up with the idea of having Morito try looking after his sister. With Morito's gentle character, the zoo keepers expected him to support Moka emotionally, even though he could not be an exact replacement for their mother. The siblings started living together from May 20.

From day one, Morito took good care of Moka, sleeping with her in his arms and carrying her on his back when she almost fell from a height. By copying Morito, Moka is learning new things daily, from eating to playing with ropes.

Orangutans spend most of their life in trees and do not form groups. It is difficult to have adult orangutans live together, especially males, even if they are from the same family, because they see each other as rivals.

"Had it been two years later, it would have been too late for them to live together," Sahashi said.

There is no other case of orangutan siblings living together in Japan, according to the zoo. "I hope Moka grows up healthy and becomes a mom," Sahashi said.

The Hokkaido Shimbun Press


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