One of the world’s six remaining northern white rhinos died at the San Diego Zoo on Sunday, according to park officials.

Angalifu, 44, reportedly died of old age and had begun refusing to eat last week, reports the Los Angeles Times.

“Angalifu’s death is a tremendous loss to all of us,” said Rancy Reiches, curator of mammals at the zoo’s Safari Park.

Myriad attempts to breed Angalifu with the park’s only other northern white rhino failed. The species now faces complete extinction after decades of wide-scale poaching.

[LAT]

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