The island is presently home to four endemic land bird species – the Henderson fruit dove, Henderson lorikeet, Henderson reed warbler and the flightless Henderson crake. Three species of the family Columbidae were formerly endemic to the island. They became extinct when the Polynesians arrived around 1000 CE. Of the fifteen non-endemic seabird species found, nine or more probably breed on the island. Breeding colonies of the globally endangered Henderson petrel formerly existed on Ducie but were wiped out by invasive rats by 1922. It is believed to now nest uniquely on Henderson island.