Egrets fly in south China's Guangxi Zhuang Autonomous Region, Dec. 4, 2018. Ecological protection in Beibu Gulf has created a friendly environment for marine products, which attract thousands of egrets to nest and reproduce here every year. (Xinhua/Zhang Ailin)

　　Egrets search for food in a pond in Kangxiling Town of Qinzhou City, south China's Guangxi Zhuang Autonomous Region, Nov. 26, 2018. Ecological protection in Beibu Gulf has created a friendly environment for marine products, which attract thousands of egrets to nest and reproduce here every year. (Xinhua/Zhang Ailin)

　　Egrets fly in sunset in south China's Guangxi Zhuang Autonomous Region, Dec. 5, 2018. Ecological protection in Beibu Gulf has created a friendly environment for marine products, which attract thousands of egrets to nest and reproduce here every year. (Xinhua/Zhang Ailin)

　　Egrets search for food in a pond in Kangxiling Town of Qinzhou City, south China's Guangxi Zhuang Autonomous Region, Nov. 26, 2018. Ecological protection in Beibu Gulf has created a friendly environment for marine products, which attract thousands of egrets to nest and reproduce here every year. (Xinhua/Zhang Ailin)

　　Egrets fly to search for food in south China's Guangxi Zhuang Autonomous Region, Dec. 4, 2018. Ecological protection in Beibu Gulf has created a friendly environment for marine products in Guangxi, which attract thousands of egrets to nest and reproduce here every year. (Xinhua/Zhang Ailin)

　　Egrets fly on sea in south China's Guangxi Zhuang Autonomous Region, Dec. 7, 2018. Ecological protection in Beibu Gulf has created a friendly environment for marine products, which attract thousands of egrets to nest and reproduce here every year. (Xinhua/Zhang Ailin)

　　Egrets rest at a pond in Kangxiling Town of Qinzhou City, south China's Guangxi Zhuang Autonomous Region, Nov. 26, 2018. Ecological protection in Beibu Gulf has created a friendly environment for marine products, which attract thousands of egrets to nest and reproduce here every year. (Xinhua/Zhang Ailin)

　　An egret rests on a pole in south China's Guangxi Zhuang Autonomous Region, Dec. 4, 2018. Ecological protection in Beibu Gulf has created a friendly environment for marine products, which attract thousands of egrets to nest and reproduce here every year. (Xinhua/Zhang Ailin)

　　Egrets search for food in a pond in Hepu County of Beihai City, south China's Guangxi Zhuang Autonomous Region, Nov. 26, 2018. Ecological protection in Beibu Gulf has created a friendly environment for marine products, which attract thousands of egrets to nest and reproduce here every year. (Xinhua/Zhang Ailin)

　　Egrets rest on seashore in south China's Guangxi Zhuang Autonomous Region, Dec. 5, 2018. Ecological protection in Beibu Gulf has created a friendly environment for marine products, which attract thousands of egrets to nest and reproduce here every year. (Xinhua/Zhang Ailin)

　　Photo taken on Dec. 5, 2018 shows a habitat of egrets, south China's Guangxi Zhuang Autonomous Region. Ecological protection in Beibu Gulf has created a friendly environment for marine products, which attract thousands of egrets to nest and reproduce here every year. (Xinhua/Zhang Ailin)

　　Egrets search for food in a pond in Hepu County of Beihai City, south China's Guangxi Zhuang Autonomous Region, Nov. 26, 2018. Ecological protection in Beibu Gulf has created a friendly environment for marine products, which attract thousands of egrets to nest and reproduce here every year. (Xinhua/Zhang Ailin)

　　Egrets search for food in a pond, south China's Guangxi Zhuang Autonomous Region, Nov. 26, 2018. Ecological protection in Beibu Gulf has created a friendly environment for marine products, which attract thousands of egrets to nest and reproduce here every year. (Xinhua/Zhang Ailin)