Almost 40 years ago, the last wild Arabian oryx (Oryx leucoryx), a large, cream-colored antelope with striking black horns, met its end in the deserts of Oman—shot by a hunter. But this week, conservationists announced that the oryx, which may have led to the legend of the unicorn, has been successfully restored to its native habitat on the Arabian Peninsula. It's the first time scientists have achieved such a remarkable turn-around for a species once declared extinct in the wild. The International Union for Conservation of Nature (IUCN) has moved the oryx from "endangered" to "vulnerable" on the organization's latest red list of threatened species.
"Certainly, this is a milestone, and a wonderful success story for captive breeding and reintroduction programs," says Kris Hundertmark, a wildlife ecologist, and former member of the IUCN's Antelope Specialist Group, now at the University of Alaska, Fairbanks. IUCN's categories are "based on measurable standards," he adds—meaning the oryx's new classification is the result of solid observations, not just a hunch.
Today, about 1000 wild oryx roam the deserts of Saudi Arabia, Israel, the United Arab Emirates, Oman, and Jordan. The population is not connected, however, nor are there corridors yet to link the scattered herds, some of which number less than 40 animals.
Unregulated hunting and poaching led to the animals' original decline. "To the extent [that illegal hunting] is controlled, the population should grow fairly rapidly," says Michael Hutchins, executive director of The Wildlife Society in Bethesda, Maryland. "Oryx are not difficult to breed in captivity or to reintroduce."
But even as the IUCN scientists celebrated the oryx's success, they noted that other species continue to decline, some drastically. The Siau Island tarsier, a primate living on Siau Island in Indonesia, and eight species of amphibians in other countries have been listed as critically endangered on the IUCN's new Red List. Overall, an estimated 41% of amphibian species worldwide are at risk of extinction. And so little is known about the populations of some other species, including one-third of all 248 lobster species, that IUCN specialists can offer no assessment of their status, and have called for more surveys.
Still, Simon Stuart, the chair of the IUCN's species survival commission says the Red List serves its purpose, bringing attention to species in critical need of help—as the oryx once was.