Heron birds perch on the tree at Petulu Gunung village in Gianyar district of Bali, Indonesia, on Dec. 11, 2019. (Photos: Xinhua)

A heron bird flies at Petulu Gunung village in Gianyar district of Bali, Indonesia, Dec. 11, 2019.

A heron bird flies over its colony at Petulu Gunung village in Gianyar district of Bali, Indonesia, on Dec. 11, 2019.