Released crested ibises, an endangered bird species once believed to be extinct in China, fly to see caged ibises at a base of re-wilding training in Tongchuan City, northwest China's Shaanxi Province, Dec. 23, 2014. The crested ibis, also known as the Japanese crested ibis, is large with white plumage, and before the 1930s had thrived in Japan, China, Russia and the Korean peninsula. But its population was sharply reduced due to wars, natural disasters, hunting and other human activities. (Xinhua/Ding Haitao)