Conserving the endemic birds on the Comoro Islands, I: general considerations on survival prospects

Abstract

SummaryThe status of the Comoro endemic birds is briefly reviewed. Field data were gathered during expeditions in 1981, 1983, 1985 and 1989.Some native birds (Cyanolanius madagascarinus, Dicrurus fuscipennis on Ngazidja, Treron australis on Mwali, Accipiter francesae, Otus rutilus, Leptosomus discolor on Ndzuani, Dicrurus waldenii on Maore) are so rare that they are certainly highly endangered. The altitudinal stenotopy of a few other species makes them also very vulnerable, e.g. Zosterops mouroniensis in the tree-heath zone on Mount Karthala above 1,750 m. A preliminary analysis of habitat preference on Ngazidja suggests a relatively large flexibility of most forest species between different types of forest, including those with altered vegetation structure, but demonstrated their absence in plantations without large trees and/or natural shrubs. Comparison of density of species in Ngazidja and Mwali and an overview of the avifaunal composition on all four islands are the basis for a discussion on colonization history (with possible extinctions), historical change in avifaunal composition, the suitability of each island for the different species and the completeness of their avifauna. The results are checked for possible threats and necessary actions for conservation. Competition by introduced species does not yet seem to be a problem. But importation of foreign animals must be banned and hunting must be regulated (especially for pigeons). Habitat loss (overexploitation of the forest) will soon become a serious problem for the stenotopie forest birds. A suggestion is made for delimiting a national park on Ngazidja and Mwali. Most controversial is the development of tourism. For long-lasting results, education of local people is necessary, together with full liaison with the authorities.