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A 44-year-old northern white rhino died of old age this week at the San Diego Zoo. This would be unremarkable, except that thousands of others have died unnaturally at the hands of poachers. Rhino horns are sold in Asia as a health tonic and status symbol. There are now five animals left of this subspecies called the northern white rhino. NPR's Gregory Warner reports why this animal is so hard to save.
GREGORY WARNER, BYLINE: Rhinos don't like to breed in zoos, so just before Christmas in 2009, four of the last northern white rhino on the planet were airlifted from a zoo in the Czech republic to a conservancy in Kenya called Ol Pejeta. They were placed in a heavily guarded, 600-acre enclosure designed to mimic their natural environment, and the half-a-million-dollar operation was called Last Chance to Survive.
The CEO of Ol Pejeta, Richard Vigne, says the rhinos soon regained wild habits like nocturnal feeding, though it took more than two years before the happy day when they were spotted mating.
RICHARD VIGNE: I don't think there was champagne on call, but I can tell you what there was, was daily visits to see if the female was getting fatter. And a lot of things were imagined. In other words, we were told repeatedly by the keepers who knew them very well that they were definitely pregnant. They were definitely changing their habits. So, you know, we convinced ourselves pretty well that this was working.
WARNER: It was a false alarm. There would be no pitter-patter of little hooves. Vigne wondered, maybe those years in a zoo cage had permanently knocked out their ability to reproduce. The conservancy is contemplating in vitro fertilization, but what's a ten-minute procedure in a dairy cow is expensive and experimental in a rhino.
VIGNE: You're dealing with a semi-wild - what? - two-ton animal, which is very different from dealing with completely domesticated cattle.
WARNER: If they are too wild to be artificially impregnated but too tame to naturally reproduce, northern white rhino might be fated to fall through the cracks of evolution. Yet another plan is being considered to extract a northern white rhino egg, fertilize it with frozen northern white rhino sperm, and implant it in the surrogate womb of a related subspecies, the southern white rhino. And the southerns have their own epic comeback story. At the turn of the last century they'd been hunted down to a mere 20 animals. They were collected, protected and bred to what is now more than 14,000.
JOHN HUME: My name is John Hume. I have bred over 700 rhinos. The southern white rhino is a relatively user-friendly animal. It wants to cooperate. It wants to breed. It does not want to go extinct.
WARNER: And John Hume breeds them the natural way, and he credits the southern white rhino's personality - its ability to adapt to survive in our human world, one difference from their northern cousins. Well, a hundred years ago when those twenty last rhino were collected and bred, they were taken straight from savannah, not from a zoo. Perhaps what's enabled the southern white rhino to breed and given them a chance to survive in this human world is that little bit of wildness that never left them.
Gregory Warner, NPR News, Nairobi.
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