There are now just three northern white rhinos on Earth, after the passing of 41-year-old Nola at the San Diego Zoo this weekend. The elderly female rhino was euthanized following a long battle with arthritis and, more recently, an infection in her hip. Zoo officials said in a statement that Nola had surgery on November 13 to drain an abscess from the bacterial infection, and her condition deteriorated in the days following the procedure. Nola is survived by three other elderly rhinos, all living on a preserve in Kenya.

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Less than three months ago, there were five of the rare rhinos in the world when Nabire, a 31-year-old female living at a zoo in the Czech Republic, died following complications with uterine cysts. The last three rhinos on the planet are Sudan, a 42-year-old male, and two females named Najin and Fatu. All three are unable to reproduce.

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Poaching is the primary reason the subspecies has dwindled to the point of extinction. Rhino horns still fetch high rewards in parts of Asia where they are believed to possess medicinal properties. The horns are ground into a powder and used to treat a wide variety of ailments.

Researchers have been looking for ways to resurrect the subspecies. Currently, their best hope is to use eggs harvested from Nabire and implanted in a southern white rhino female using in vitro fertilization. The San Diego Zoo, Nola’s home until her passing, acquired six female southern white rhinos this month from South Africa, and those rhinos will become surrogate mothers as soon as fertilized embryos are ready for implantation.

Via The Guardian

Images via Wikipedia (1, 2)