Swans are seen at a wetland in Shahe City, north China's Hebei Province, Dec. 9, 2020. (Xinhua/Mu Yu)
Swans are seen at a wetland in Shahe City, north China's Hebei Province, Dec. 9, 2020. (Xinhua/Mu Yu)
Swans are seen at a wetland in Shahe City, north China's Hebei Province, Dec. 9, 2020. (Xinhua/Mu Yu)
Swans fly over a wetland in Shahe City, north China's Hebei Province, Dec. 9, 2020. (Xinhua/Mu Yu)
Swans fly over a wetland in Shahe City, north China's Hebei Province, Dec. 9, 2020. (Xinhua/Mu Yu)
