Siberian tigers play during a rewilding training in Siberian Tiger Park in Harbin, capital of northeast China's Heilongjiang Province, Jan. 28, 2018. In winter, staff members brought captive tigers to the outdoor environment to train their preying skills at the world's largest breeding center for Siberian tigers. China has been trying to save the species through captive breeding programs. When the center opened in 1986, it had only eight tigers, now it is home to more than 1,000. (Xinhua/Wang Zhaobo)