Photo taken on March 30, 2019 shows a herd of wild yaks in the Altun Mountains National Nature Reserve in northwest China's Xinjiang Uygur Autonomous Region. Altun Mountain National Nature Reserve saw the number of three rare wild animals reach around 100,000, according to local researchers. The population of wild yak, Tibetan antelope and wild ass is recovering to the level of recorded data in the 1980s when the reserve was first set up, the results of the latest scientific investigation showed. The reserve suspended all mining activities within its 46,800-square-km parameter in 2018 in an effort to restore its environment. [Photo/Xinhua]