Article

During a survey of the birds of the Cook Islands from July-September 1973, the birds of the islands of Atiu, Mitiaro, Mauke and Mangaia were investigated for the first time. Series of seven land birds that apparently represent undescribed forms were collected. This paper gives descriptions of these forms, in advance of a fuller report on their biology and that of the other birds seen.

Since Elton highlighted the problem of biological invasions, numerous studies have established their importance in the structural evolution of natural communities, in particular insular communities. Because of their isolation, islands are regarded as natural evolution laboratories which are characteristically very fragile once the boundary is disturbed. This fragility is illustrated by the high proportion of species extinctions observed in islands: since 1600, more than 75% of monitored disappearances have been registered in islands.

The Kuramoo, or Blue Lorikeet (Vini peruviana), is listed by IUCN as threatened. Formerly, the species was widespread on the Society and Tuamotu ISlands, but it became extinct on Tahiti, Moorea and other large islands in the Society Group early this century and is now also extinct on many other islands on which it once occurred. Today, in French Polynesia, it apparently survives only on two small islands in the Society Group and several in the Tuamotu Group.

During a visit to the Cook Islands, my wife and I spent 5 days (30 August to 3 September 1980) on Aitutaki, where we made a concerted effort to determine the composition and status of the birdlife.

The role and nature of Tara taranaki are described. Its links to other species are considered; and the possible effects of possums on the species is discussed. It is likely that 1080 poison is highly toxic to amphipods, but no matter how poisonous it is to Tara taranaki, its use is likely to be far less damaging in the long term to this species than are the effects of an uncontrolled possum population.

Observations made during visits to Rarotonga in July and August 1976 are detailed, with particular reference to land birds and petrels, a group not previously recorded. The outstanding feature of the land bird ecology is the apparent total restriction of the native species except Long-tailed cuckoo to the central primitive forests and adjacent second growth. The native land bird fauna consists of only five species: Long-tailed Cuckoo, Pacific Pigeon, Rarotonga Fruit Dove, Rarotonga Flycatcher and the Rarotonga Starling, of which the last three are endemic.