Dramatic decline of the threatened Ili pika Ochotona iliensis (Lagomorpha: Ochotonidae) in Xinjiang, China

Abstract

The Vulnerable Ili pika Ochotona iliensis (Lagomorpha: Ochotonidae) is a poorly known mammal species that inhabits a restricted geographic range in the Tian Shan Mountains, Xinjiang Uygur Autonomous Region, China. It was discovered in 1983, described in 1986, and subsequently investigated over the following decade. As no studies were conducted on this pika during the next 10 years, a comprehensive census was undertaken in the summers of 2002 and 2003, including all sites where it had previously been observed. Evidence of the Ili pika was found at only 6 of 14 sites censused, and was extinct in two of six regions, including the type and paratype localities (Jilimalale Mountain). Ili pika populations appear to have declined in three of six regions, and in only one region did the population appear to be comparable to a decade earlier. Like all rock-dwelling pikas, the Ili pika has a low population density and rate of reproduction. Additionally, populations on its preferred habitat of cliff faces are highly fragmented. Increased temperatures, possibly due to global warming, and increased grazing pressure may have interacted with the normal population dynamics of the Ili pika to contribute to its recent dramatic decline. We recommend that the Ili pika's Red List status be changed from Vulnerable to Endangered.