ENDEMIC BUTTERFLIES ON GRANDE-COMORE - HABITAT PREFERENCES AND CONSERVATION PRIORITIES

The island of Grande Comore (Comoro Islands, western Indian Ocean) has an endemic butterfly fauna threatened by rapid habitat change. Transe ct counts were used to assess the abundance and species richness of bu tterflies in different habitats, and along an elevational gradient. Sp ecies richness of non-endemic butterflies was highest in low elevation , man-modified habitats. In contrast, most endemic butterflies were co nfined to forest habitats, which only remain above 500 m elevation. Ri chness and abundance of endemic butterflies were highest at the lower elevational limits of the remaining forest. Controlling for elevation, the richness of endemic butterflies was highest in mature forest wher e the gross structure of the forest remained intact, lower in scrubby secondary forest, and lowest in pioneer forest on old lava flows. The survival of the majority of the endemic butterflies may depend on fore st conservation measures in the rapidly diminishing areas of mature fo rest at mid elevations. (C) 1998 Elsevier Science Ltd. All rights rese rved.