A chimpanzee feeds on a piece of frozen watermelon to cool off from summer heat waves at Chongqing Zoo in southwest China's Chongqing, July 13, 2018. (Photo: Xinhua)

A staff member feeds frozen food to giant pandas as a relief from summer heat waves at Chongqing Zoo in southwest China's Chongqing, July 13, 2018. (Photo: Xinhua)

Staff members shear a llama to help it cool off from summer heat waves at Chongqing Zoo in southwest China's Chongqing, July 13, 2018.(Photo: Xinhua)

Frozen food is offered to a common squirrel monkey to help it cool off from summer heat waves at Chongqing Zoo in southwest China's Chongqing, July 13, 2018. (Photo: Xinhua)

Giant pandas feed on frozen food to cool off from summer heat waves at Chongqing Zoo in southwest China's Chongqing, July 13, 2018. (Photo: Xinhua)

Two monkeys cool off in a pond in Hongshan Forest Park in Nanjing, east China's Jiangsu Province, July 13, 2018. Zoo authorities have taken measures to keep the animals cool in the summer around China. (Photo: Xinhua)

A giant panda cools off in a room equipped with air-conditioner in Hongshan Forest Park in Nanjing, east China's Jiangsu Province, July 13, 2018. Zoo authorities have taken measures to keep the animals cool in the summer around China. (Photo: Xinhua)