Egrets fly over the Yundang Lake in Xiamen, southeast China's Fujian Province, Sept. 20, 2020. The number of birds is on an upward trend in Xiamen as local ecological environment continues to improve. (Xinhua/Wei Peiquan)

An egret catches a fish on the Yundang Lake in Xiamen, southeast China's Fujian Province, Sept. 20, 2020. The number of birds is on an upward trend in Xiamen as local ecological environment continues to improve. (Xinhua/Wei Peiquan)

Egrets fly over the Yundang Lake in Xiamen, southeast China's Fujian Province, Sept. 20, 2020. The number of birds is on an upward trend in Xiamen as local ecological environment continues to improve. (Xinhua/Wei Peiquan)

An egret catches a fish on the Yundang Lake in Xiamen, southeast China's Fujian Province, Sept. 20, 2020. The number of birds is on an upward trend in Xiamen as local ecological environment continues to improve. (Xinhua/Wei Peiquan)