Migrant birds rest at the wetland in Momoge National Nature Reserve in Zhenlai County, Baicheng City of northeast China's Jilin Province, Oct. 13, 2020. (Photos: Xinhua)

Migrant birds fly over the wetland in Momoge National Nature Reserve in Zhenlai County, Baicheng City of northeast China's Jilin Province, Oct. 13, 2020.

Migrant birds forage at the wetland in Momoge National Nature Reserve in Zhenlai County, Baicheng City of northeast China's Jilin Province, Oct. 13, 2020.

Migrant birds rest at the wetland in Momoge National Nature Reserve in Zhenlai County, Baicheng City of northeast China's Jilin Province, Oct. 13, 2020.

Migrant birds rest at the wetland in Momoge National Nature Reserve in Zhenlai County, Baicheng City of northeast China's Jilin Province, Oct. 13, 2020.

Migrant birds fly over the wetland in Momoge National Nature Reserve in Zhenlai County, Baicheng City of northeast China's Jilin Province, Oct. 13, 2020.

Migrant birds fly over the wetland in Momoge National Nature Reserve in Zhenlai County, Baicheng City of northeast China's Jilin Province, Oct. 13, 2020.

Migrant birds fly over the wetland in Momoge National Nature Reserve in Zhenlai County, Baicheng City of northeast China's Jilin Province, Oct. 13, 2020.