Very remote, high altitude haven proving a saviour for wild yak

Wild yaks at the edge of a glacier on the Tibetan plateau. Joel Berger/WCS/University of Montana

January 2013. A team of American and Chinese conservationists from the Wildlife Conservation Society and University of Montana recently counted nearly 1,000 wild yaks in a remote area of the Tibetan-Qinghai Plateau. The finding may indicate a comeback for this species, which was decimated by overhunting in the mid-20th century.

990 yaks in Hoh Xil National Nature Reserve
The team counted 990 yaks in a rugged area called Hoh Xil - a national nature reserve nearly the size of West Virginia but devoid of people. The remote region lies in the mid-eastern Tibetan-Himalayan highlands, home to some 17,000 glaciers - an area sometimes called the "3rd pole" due to its Arctic-like conditions.

Third largest mammal in Asia
Wild yaks are the third largest mammal in Asia, second only to elephants and rhinos. Adults are estimated to be the size of bison, but - because the area where they occur is so isolated - wild yaks have never been officially weighed. Fifty years ago, the Tibetan steppe was dotted with wild yak much in the way that bison once stretched across vast North American prairies. Like bison, wild yaks were slaughtered. Yak skulls still litter high elevation haunts up to 17,500 feet.

Wild yak population estimates across the Tibetan-Qinghai Plateau are unknown, though conservationists believe they may be making a comeback due to conservation efforts by Chinese park officials and provincial governments. Recently, the Qinghai provincial government has launched several conservation related policies and regional projects in order to develop a sound basis for wildlife and environmental conservation in this region.

"Wild yaks are icons for the remote, untamed, high-elevation roof of the world," said Joel Berger who led the expedition for WCS and the University of Montana. "While polar bears represent a sad disclaimer for a warming Arctic, the recent count of almost 1000 wild yaks offers hope for the persistence of free-roaming large animals at the virtual limits of high-altitude wildlife."

Hybridization
Berger and his colleagues found greater yak densities near glaciers, which often support adjacent food-rich alpine meadow habitats. Less than one percent of the yaks observed showed colour variation, a good indication that hybridization with their more colourful domestic yak cousins is less frequent here than in more peopled regions on the Tibetan Plateau.

Very little is known about wild yak biology, including how often they reproduce, infant mortality rates, and the role wolves may play on population dynamics.

The team's next steps will be to process data to understand more about climate change impacts on this high elevation ecosystem, and to unravel more about human-wildlife conflict in this fragile and little-known part of the world.

Joe Walston WCS Executive Director of Asia Programs, said: "For millennia, yaks have sustained human life in this part of Asia, it would be a cruel irony if their reward is extinction in the wild. Thankfully, we have a chance now to secure their future and give back a little of what they have provided us."

The expedition was sponsored by the National Geographic Society, WCS, and the University of Montana. Hoh Xil National Nature Reserve and Qinghai Provincial Forestry Bureau of China provided invaluable support to make it happen.

Wild yak on the Tibetan plateau. Photo credit Joel Berger/WCS/University of Montana