Wintering whooper swans seen at Yellow River in NW China's Qinghai

Wintering whooper swans are seen at the Yellow River in Hualong Hui Autonomous County of Haidong City, northwest China's Qinghai Province, Dec. 23, 2022. (Xinhua/Wu Gang)

Wintering whooper swans are seen at the Yellow River in Hualong Hui Autonomous County of Haidong City, northwest China's Qinghai Province, Dec. 23, 2022. (Xinhua/Wu Gang)

Wintering whooper swans are seen at the Yellow River in Hualong Hui Autonomous County of Haidong City, northwest China's Qinghai Province, Dec. 23, 2022. (Xinhua/Wu Gang)

Wintering whooper swans are seen at the Yellow River in Hualong Hui Autonomous County of Haidong City, northwest China's Qinghai Province, Dec. 23, 2022. (Xinhua/Wu Gang)

Wintering whooper swans are seen at the Yellow River in Hualong Hui Autonomous County of Haidong City, northwest China's Qinghai Province, Dec. 23, 2022. (Xinhua/Wu Gang)

Wintering whooper swans are seen at the Yellow River in Hualong Hui Autonomous County of Haidong City, northwest China's Qinghai Province, Dec. 23, 2022. (Xinhua/Wu Gang)

Wintering whooper swans are seen at the Yellow River in Hualong Hui Autonomous County of Haidong City, northwest China's Qinghai Province, Dec. 23, 2022. (Xinhua/Wu Gang)

Wintering whooper swans are seen at the Yellow River in Hualong Hui Autonomous County of Haidong City, northwest China's Qinghai Province, Dec. 23, 2022. (Xinhua/Wu Gang)

Wintering whooper swans are seen at the Yellow River in Hualong Hui Autonomous County of Haidong City, northwest China's Qinghai Province, Dec. 23, 2022. (Xinhua/Wu Gang)

Wintering whooper swans are seen at the Yellow River in Hualong Hui Autonomous County of Haidong City, northwest China's Qinghai Province, Dec. 23, 2022. (Xinhua/Wu Gang)

Wintering whooper swans are seen at the Yellow River in Hualong Hui Autonomous County of Haidong City, northwest China's Qinghai Province, Dec. 23, 2022. (Xinhua/Wu Gang)