South East Island (Rangatira) is the most important reserve for oceanic and terrestrial bird life in the Chatham Islands, and one of the largest islands free of mammalian predators in the New Zealand region. The avifauna consists of 66 species: there are confirmed records of breeding or attempted breeding for 33 of these. The rest are either vagrants or forage in adjacent waters. Two species, Shore Plover Thinornis novaeseelandiae and Chatham Petrel Pterodroma axillaris breed only on this island. A further six species are endemic to the Chathams, but are rare elsewhere in the group; five of them are abundant. Historical and contemporary records are covered. During the past 150 years, the vegetation of the island has been altered substantially, by fire and grazing. The changes have influenced the fauna greatly, and its original composition and character are unclear.