The ‘Ata IBA comprises the whole of the 2.3 sq.km. volcanic island of ‘Ata, the southernmost island of the Tongan archipelago. The island is mostly forested and is currently uninhabited and very rarely visited by people. ’Ata has some of the largest seabird colonies in Tonga especially wedge-tailed shearwaters, masked, red-footed and brown booby, and black and brown boobies. Together these are believed to number over 50,000 birds.
‘Ata is renowned for its seabird colonies but these remain very poorly documented. Apart from the collectors of the Whitney South Sea Expedition who visited the island 13-14 July 1925, only Rinke (1991) has published ornithological observations. The apparent loss of the Pacific harrier and the exotic European starling between the visits of the WSSE and Dieter Rinke’s visit is of great interest. The island indubitably supports over 10,000 pairs of seabirds (A4iii), probably comprising 15 species. Whilst the breeding populations of the three species of booby and the two species of noddy both fulfill IBA criteria (A4ii). In addition, the Polynesian starling is a ‘central polynesian’ restricted range species (A2).
Non-bird biodiversity: Rinke (1991) records the abundance of Ficus spp.in the forest on the plateau, as well as the presence of Inocarpus edulis and coconuts and pawpaw. Other species noted include Wedelia biflora thickets, Pisonia grandis, Hibiscus tiliaceus and Casuarina equisetifolia. He confirmed the presence of the Polynesian rat Rattus exulans and three skinks. Emoia cyanura, E.pheonura and Cryptoblepharus eximius.
BirdLife International (2020) Important Bird Areas factsheet: 'Ata Island. Downloaded from http://www.birdlife.org on 17/02/2020.