File photo shows some bird eggs in the artificial nest built by Luo Kang, a PhD candidate of Chinese Academy of Sciences, in the Ailao Mountains, southwest China’s Yunnan Province. (Photos: IC)

File photo shows newly hatched birds in the artificial nest built by Luo Kang, a PhD candidate of Chinese Academy of Sciences, in the Ailao Mountains, southwest China’s Yunnan Province.

Undated photo shows Luo Kang, a PhD candidate of Chinese Academy of Sciences, working in the AilaoMountains, southwest China’s Yunnan Province.

Undated photo shows Luo Kang, a PhD candidate of Chinese Academy of Sciences, working in the AilaoMountains, southwest China’s Yunnan Province.

Undated photo shows Luo Kang, a PhD candidate of Chinese Academy of Sciences, working in the AilaoMountains, southwest China’s Yunnan Province.