Blue-tailed bee eaters are seen in Haikou, south China's Hainan Province, May 7, 2020. Every year from spring to summer, bee eaters usually come to a fixed site for reproduction. Local authorities of Haikou has made full preparations for bee eaters to build a better habitat during their breeding season. (Xinhua/Yang Guanyu)

Blue-tailed bee eaters are seen in Haikou, south China's Hainan Province, May 7, 2020. Every year from spring to summer, bee eaters usually come to a fixed site for reproduction. Local authorities of Haikou has made full preparations for bee eaters to build a better habitat during their breeding season. (Xinhua/Yang Guanyu)

Blue-tailed bee eaters are seen in Haikou, south China's Hainan Province, May 7, 2020. Every year from spring to summer, bee eaters usually come to a fixed site for reproduction. Local authorities of Haikou has made full preparations for bee eaters to build a better habitat during their breeding season. (Xinhua/Yang Guanyu)

Blue-tailed bee eaters are seen in Haikou, south China's Hainan Province, May 8, 2020. Every year from spring to summer, bee eaters usually come to a fixed site for reproduction. Local authorities of Haikou has made full preparations for bee eaters to build a better habitat during their breeding season. (Xinhua/Yang Guanyu)

Blue-tailed bee eaters are seen in Haikou, south China's Hainan Province, May 7, 2020. Every year from spring to summer, bee eaters usually come to a fixed site for reproduction. Local authorities of Haikou has made full preparations for bee eaters to build a better habitat during their breeding season. (Xinhua/Yang Guanyu)