Yuan Xueshun greets swans with food at the wetland of the Swan Lake in Chengshan Town of Rongcheng City, east China's Shandong Province, Feb. 14, 2018. Yuan Xueshun, dubbed as "swan guard," has devoted himeself to the protection of swans for over 40 years. He has rescued more than 1,000 sick or wounded swans and succeeded in preventing more than 1,000 mu (66.67 hectares) of wetland from being destroyed since 1975. Thanks to the efforts made by people like Yuan, the Swan Lake in Rongcheng has become an ideal habitat for swans in winter. (Xinhua/Feng Jie)