Sudan, the world’s last male northern white rhino, grazes at the Ol Pejeta Conservancy in Kenya in May 2017. The 45-year-old rhino’s health started deteriorating in late February.

Sudan, the world’s last male northern white rhino, grazes at the Ol Pejeta Conservancy in Kenya in May 2017. The 45-year-old rhino’s health started deteriorating in late February.