Photo taken on Sept. 21, 2016 shows two Siberian tiger cubs in the Harbin Base of the Hengdaohezi Felid Breeding Center in Harbin, northeast China's Heilongjiang Province. Over 100 tiger cubs have been born in the center by the end of mid-September this year. The peak season for the breeding of Siberian tigers is in May and June. The cubs will be sent to a semi-wild environment to learn running and hunting when they grow up. The center was established in 1986 for better protection of the species. (Xinhua/Wang Jianwei)