Children gather at a camp in Qingdao Haichang Polar Ocean Park in Qingdao, a coastal city in east China's Shandong Province, May 19, 2018. Children would stay at the ocean park all night to make close contact with marine animals. (Xinhua/Li Ziheng)

Children gather at a camp in Qingdao Haichang Polar Ocean Park in Qingdao, a coastal city in east China's Shandong Province, May 19, 2018. Children would stay at the ocean park all night to make close contact with marine animals. (Xinhua/Li Ziheng)

Children gather at a camp in Qingdao Haichang Polar Ocean Park in Qingdao, a coastal city in east China's Shandong Province, May 19, 2018. Children would stay at the ocean park all night to make close contact with marine animals. (Xinhua/Li Ziheng)

A little girl stays at a camp in Qingdao Haichang Polar Ocean Park in Qingdao, a coastal city in east China's Shandong Province, May 19, 2018. Children would stay at the ocean park all night to make close contact with marine animals. (Xinhua/Li Ziheng)

Children view a shark as joining in a camp in Qingdao Haichang Polar Ocean Park in Qingdao, a coastal city in east China's Shandong Province, May 19, 2018. Children would stay at the ocean park all night to make close contact with marine animals. (Xinhua/Li Ziheng)