File photo taken on July 12, 2010 shows a Siberian tiger climbing up a tree to catch a chicken during a wildlife training in the Siberian tiger preservation park in Mudanjiang, northeast China's Helongjiang Province. It is estimated that there are merely 50-60 wild tigers surviving in China. More tigers are artificially bred in captivity. The wildness of those tigers raised in captivity has degenerated, thus leading to difficulties for their natural mating and wild living. They have become too familiar with humans and lost their natural wildness. [Xinhua]