The Arabian oryx, a desert antelope that may have sparked the legend of the unicorn, has bounced back after being hunted almost to oblivion, the International Union for Conservation of Nature (IUCN) said on Thursday.
Native to the Arabian peninsula, Oryx leucoryx has two long slender horns that in profile look as one, which may have fuelled the myth of the unicorn, the IUCN said.
The last Arabian oryx in the wild was shot in 1972 but after a nearly 40-year effort in captive breeding, its population stands at 1,000 individuals, the IUCN said, trailing an update of its "Red List" of threatened species.
An oryx was successfully reintroduced to the wild in Oman in 1982 and other returns have taken place in Saudi Arabia, Israel, the United Arab Emirates and more recently in Jordan.
The oryx has now qualified for a move under the Red List from "endangered" category to "vulnerable," the first time that a species that had been extinct in the wild has improved by three categories.
"To have brought the Arabian oryx back from the brink of extinction is a major feat and a true conservation success story, one which we hope will be repeated many times over for other threatened species," the IUCN quoted Razan Khalifa Al Mubarak, head of Abu Dhabi's environment agency, as saying.
The Red List, an assessment of 59,508 plant and animal species, is a major guide to policymakers.
It is the biggest biodiversity compendium available, although it still covers only a fraction of the world's vast range of species.
The update says that 797 species are extinct and 64 are extinct in the wild.
Another 3,801 are "critically endangered" by global extinction; 5,566 are endangered and 9,898 are vulnerable to this threat.
A further 4,533 species are "near threatened" - meaning they are close to the "threatened" threshold - or are dependent on conservation efforts.
Of the remaining species, 25,853 fall into a category of "least concern" while there is insufficient data to judge the status of 8,996 others.
Those in this latter category include the Wallace's tarsier, a primate found last year in two small areas of forest in central Sulawesi, Indonesia.
The IUCN sounded the alarm for amphibians, saying that 41 percent of species were at risk of extinction as a result of habitat loss, pollution, disease and competition from invasive species.
The IUCN's methodology, and that used by the 2005 UN Millennium Ecosystem Assessment and the 2007 Intergovernmental Panel on Climate Change (IPCC) report, were questioned in a study published last month.
It agreed that biodiversity was under extreme pressure but said the true rate of extinctions, if based on the criteria of habitat loss, was less than half.
The IUCN's media officer, Borjana Pervan, said the agency had taken note of the study but was satisfied with its methods, including the uncertainties of calculating species threat.
"The actual number of threatened species is often uncertain because it is not known whether data-deficient species are actually threatened or not," the IUCN said.