 The islands are one of the most important breeding sites for tropical seabirds in Australia and have been identified by BirdLife International as an Important Bird Area (IBA).They contain by far the largest colonies of wedge-tailed shearwater in the eastern Indian Ocean, with over a million breeding pairs recorded there in 1994.They also contain Western Australia's only breeding colonies of the lesser noddy, and the largest colonies in Western Australia of the little shearwater, white-faced storm petrel, common noddy, Caspian tern, crested tern, roseate tern and fairy tern.