A study led by the Wildlife Conservation Society and Zoological Society or London assessed 14 desert species and found half of them are regionally extinct or confined to 1 percent or less of their historical range, a WCS release said Tuesday.
The causes of the declines are difficult to determine because of a chronic lack of studies across the region, due to past and ongoing insecurity, the study author said, although overhunting is likely to have played a role.
"The Sahara serves as an example of a wider historical neglect of deserts and the human communities who depend on them," study lead author Sarah Durant said. "The scientific community can make an important contribution to conservation in deserts by establishing baseline information on biodiversity and developing new approaches to sustainable management of desert species and ecosystems."
Some governments have begun to make commitments to protect the Sahara, the researchers noted.
Niger just established the 37,451-square-mile Termit and Tin Toumma National Nature Reserve, home to most of the world's 200 or so remaining wild addax, a type of antelope, and one of a handful of surviving populations of dama gazelle and Saharan cheetah.
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