Photo taken on June 15, 2018 shows a golden monkey at a nature reserve in Longnan City, northwest China's Gansu Province. After adopting measures to protect the eco-environment and wild life, the number of golden monkeys here has seen remarkable increase. (Xinhua/Zhang Meng)

Photo taken on June 15, 2018 shows a visitor feeding a golden monkey at a nature reserve in Longnan City, northwest China's Gansu Province. After adopting measures to protect the eco-environment and wild life, the number of golden monkeys here has seen remarkable increase. (Xinhua/Zhang Meng)

Photo taken on June 15, 2018 shows a golden monkey at a nature reserve in Longnan City, northwest China's Gansu Province. After adopting measures to protect the eco-environment and wild life, the number of golden monkeys here has seen remarkable increase. (Xinhua/Zhang Meng)

Photo taken on June 15, 2018 shows golden monkeys at a nature reserve in Longnan City, northwest China's Gansu Province. After adopting measures to protect the eco-environment and wild life, the number of golden monkeys here has seen remarkable increase. (Xinhua/Zhang Meng)

Photo taken on June 15, 2018 shows a golden monkey at a nature reserve in Longnan City, northwest China's Gansu Province. After adopting measures to protect the eco-environment and wild life, the number of golden monkeys here has seen remarkable increase. (Xinhua/Zhang Meng)

Photo taken on June 15, 2018 shows a visitor feeding a golden monkey at a nature reserve in Longnan City, northwest China's Gansu Province. After adopting measures to protect the eco-environment and wild life, the number of golden monkeys here has seen remarkable increase. (Xinhua/Zhang Meng)

Photo taken on June 15, 2018 shows a golden monkey at a nature reserve in Longnan City, northwest China's Gansu Province. After adopting measures to protect the eco-environment and wild life, the number of golden monkeys here has seen remarkable increase. (Xinhua/Zhang Meng)

Photo taken on June 15, 2018 shows a golden monkey at a nature reserve in Longnan City, northwest China's Gansu Province. After adopting measures to protect the eco-environment and wild life, the number of golden monkeys here has seen remarkable increase. (Xinhua/Zhang Meng)