January 17, 2013
After Near Extinction, Tibet’s Wild Yaks Make A Dramatic Comeback
April Flowers for redOrbit.com - Your Universe Online
A multinational team of conservationists from the University of Montana and the Wildlife Conservation Society recently counted nearly 1,000 wild yaks in a remote area of the Tibetan-Qinghai Plateau. The species was nearly decimated in the mid-twentieth century by overhunting, and this find may indicate a significant comeback.
The team of Americans and Chinese counted 990 yaks in a rugged nature reserve called Hoh Xil. The reserve is about the size of West Virginia but is essentially empty of human inhabitants. Sometimes called the "3rd pole" due to its Arctic-like conditions, Hoh Xil lies in the mid-eastern Tibetan-Himalayan highlands — home to some 17,000 glaciers.
Coming in third behind elephants and rhinos, wild yaks are some of the largest mammals in Asia, with adults estimated to weight about the same as the American bison. Because the area where the yaks roam is so isolated, however, wild yaks have never been officially weighed. Like the bison of the North American prairies, 50 years ago the wild yak covered the Tibetan steppe. And like the bison, the yak were slaughtered en masse throughout the early twentieth century to the point where yak skulls still litter elevation sites up to 17,500 feet.
Population estimates for the wild yak of the Tibetan-Qinghai Plateau are unknown. However, due to efforts by the Chinese park officials and provincial governments, conservationists believe that the species is making a comeback. Special conservation related policies and regional projects recently launched by the Qinghai province government are helping to develop a sound basis for wildlife and environmental conservation in the area.
"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."
Berger and his team found more dense populations of yak near glaciers which often support adjacent food-rich alpine meadow habitats. There does not appear to be much hybridization with the more colorful domesticated yak, as only one percent of the wild yak observed showed any color variation. Hybridization is more common in areas of higher human population.
Because of the remoteness of the locations where they congregate, very little is known about wild yak biology, including how often they reproduce, infant mortality rates and the role wolves may play in their population dynamics.
For their next project, the team plans to process data to understand more about climate change impacts on high elevation ecosystem. They also want to unravel more about human-wildlife interactions and conflict in this little-studied region 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 National Geographic Society and the University of Montana provided funding for this study.