A flock of little swans fly in the sky over the Donggu Lake wetland of the Quyuan administration area in Yueyang City, central China's Hunan Province, Nov. 27, 2021. About 3,000 little swans have arrived at the Donggu Lake wetland of the Quyuan administration area in Yueyang for wintering. (Photo by Cao Zhengping/Xinhua)

Little swans are seen at the Donggu Lake wetland of the Quyuan administration area in Yueyang City, central China's Hunan Province, Nov. 27, 2021. About 3,000 little swans have arrived at the Donggu Lake wetland of the Quyuan administration area in Yueyang for wintering. (Photo by Cao Zhengping/Xinhua)

Little swans are seen at the Donggu Lake wetland of the Quyuan administration area in Yueyang City, central China's Hunan Province, Nov. 26, 2021. About 3,000 little swans have arrived at the Donggu Lake wetland of the Quyuan administration area in Yueyang for wintering. (Photo by Cao Zhengping/Xinhua)

Little swans are seen at the Donggu Lake wetland of the Quyuan administration area in Yueyang City, central China's Hunan Province, Nov. 27, 2021. About 3,000 little swans have arrived at the Donggu Lake wetland of the Quyuan administration area in Yueyang for wintering. (Photo by Cao Zhengping/Xinhua)

Little swans are seen at the Donggu Lake wetland of the Quyuan administration area in Yueyang City, central China's Hunan Province, Nov. 27, 2021. About 3,000 little swans have arrived at the Donggu Lake wetland of the Quyuan administration area in Yueyang for wintering. (Photo by Cao Zhengping/Xinhua)

Source: Xinhua