Black-naped Tern

The black-naped tern, Sterna sumatrana, is an oceanic tern found mostly in tropical and subtropical parts of the Indian Ocean and western Pacific Ocean, originally described from islands near Sumatra, and it is most closely related to the roseate tern and the white-fronted tern. It occurs in two subspecies, with S. s. sumatrana ranging from the eastern Indian Ocean through the western Pacific from Taiwan south to Queensland, Australia, and S. s. mathewsi confined to islands of the western Indian Ocean, and it favors rocky shores, migrating to oceanic islands to breed. The IUCN lists it as Least Concern. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/