In Central Asia, uncontrolled hunting of cheetahs and their prey, severe winters and conversion of grassland to areas used for agriculture contributed to the population's decline. By the early 20th century, the range in Central Asia had decreased significantly. By the 1930s, cheetahs were confined to the Ustyurt plateau and Mangyshlak Peninsula in Kazakhstan and Uzbekistan, and to the foothills of the Kopet Dag mountains and a region in the south of Turkmenistan bordering Iran and Afghanistan. The last known record in this area between the Tejen and Murghab Rivers dates to 1957, in the Ustyurt plateau to July 1983, and in the Kopet Dag to November 1984. Officers of the Badhyz State Nature Reserve did not sight a cheetah in this area until 2014; the border fence between Iran and Turkmenistan might impede dispersal.