PATTERNS OF DIVERSITY AND ENDEMISM IN EAST-AFRICAN LAND SNAILS, AND THE IMPLICATIONS FOR CONSERVATION

The east African region (Kenya, Tanzania and Uganda) is rich in land s nails but the great majority of species are confined to forest habitat s which occupy only 2-3% of land area and are under considerable press ure. Since most conservation efforts in the area focus on savannah eco systems, this concentration of mollusc species in forests means that t here must be some concern for the future of the region's molluscan bio diversity. Using field data obtained from 15 forests in 5 biogeographi cal zones throughout Tanzania and Kenya, this paper presents a prelimi nary analysis of the patterns of diversity and endemism in east Africa n land snails. Faunas from some areas, notably the Indian Ocean coasta l forests, are characterised by endemic species with very small ranges . Elsewhere, for example in western Kenya, range sizes appear to be mu ch larger The conservation implications of these patterns of endemism and diversity are discussed. The effects on molluscan biodiversity of further losses of already highly fragmented coastal forest habitats ar e assessed.