Flocks of migratory birds fly over the wetland of the Wuxing white crane conservation area by the Poyang Lake in Nanchang, east China's Jiangxi Province, Dec. 21, 2020. Numerous migratory birds including white cranes and swans have arrived in the wetland by the Poyang Lake, taking it as their winter habitat. (Xinhua/Wan Xiang)

White cranes fly over the wetland of the Wuxing white crane conservation area by the Poyang Lake in Nanchang, east China's Jiangxi Province, Dec. 21, 2020. Numerous migratory birds including white cranes and swans have arrived in the wetland by the Poyang Lake, taking it as their winter habitat. (Xinhua/Wan Xiang)

White cranes are seen in the wetland of the Wuxing white crane conservation area by the Poyang Lake in Nanchang, east China's Jiangxi Province, Dec. 21, 2020. Numerous migratory birds including white cranes and swans have arrived in the wetland by the Poyang Lake, taking it as their winter habitat. (Xinhua/Wan Xiang)

A migratory bird forages in the wetland of the Wuxing white crane conservation area by the Poyang Lake in Nanchang, east China's Jiangxi Province, Dec. 21, 2020. Numerous migratory birds including white cranes and swans have arrived in the wetland by the Poyang Lake, taking it as their winter habitat. (Xinhua/Wan Xiang)

Flocks of migratory birds forage in the wetland of the Wuxing white crane conservation area by the Poyang Lake in Nanchang, east China's Jiangxi Province, Dec. 21, 2020. Numerous migratory birds including white cranes and swans have arrived in the wetland by the Poyang Lake, taking it as their winter habitat. (Xinhua/Wan Xiang)