Administrator He Shengshan tracks giant pandas in Wolong Tiantai Mountain Wild Training Fields for giant pandas, southwest China's Sichuan Province, Aug. 29, 2016. With the increasing number of giant pandas bred and kept in captivity, China started sending captive-bred pandas into the wild in 2006 in an effort to improve the genetic diversity and quality of the species. (Xinhua/Xue Yubin)