A critically endangered species of rhinoceros has been born at an Indonesian sanctuary.

The Indonesian government announced Saturday that a male Sumatran rhino calf was born to his mother, 7-year-old Delilah, at the Sumatran Rhino Sanctuary at Way Kambas National Park in the Lampung province.

While Delilah gave birth on her 460th day of pregnancy, or about 10 days earlier than expected, both the mother and the calf are being monitored and are doing well. The calf, whose name has not been announced, is able to stand upright and walk.

The rhino calf is the first for Delilah and for his father Harapan, a male rhino born at the Cincinnati Zoo and Botanical Garden, and the last Sumatran rhino to be repatriated to Indonesia.

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Sumatran rhino population

According to the Indonesian government, there are no other Sumatran rhinos left outside of Indonesia.

Sumatran rhinos are the smallest of living rhinos, and are the only Asian rhinos with two horns. According to the World Wildlife Fund, they are covered with long hair, and are more closely related to the extinct woolly rhinos than other rhinoceros species today. They are also critically endangered, with around 40 left.

In the wild, Sumatran rhinos live in isolated fragments of forest in Sumatra and Borneo, according to Save the Rhino. The species rarely meets to breed and is struggling to increase their numbers.

The rhino calif is the result of a breeding program, and the Sumatran Rhino Sanctuary hopes to someday release them back into their natural habitat.

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