Species-area curves and populations of large mammals in African savanna reserves

Abstract

Insular species-area relations were found to apply to the number of species of large herbivores occurring in populations of ⩾100, ⩾250 and ⩾1000 in 17 African savanna reserves. A similar relation was found for the number of large carnivore species occurring in populations of ⩾25 in seven reserves. Assuming that the minimum viable populations of large mammals exceed 100 for herbivores and 25 for carnivores, these findings imply that very large reserves (> 10 000 km 2) are necessary to ensure the survival of the diverse large mammal communities characteristic of the African savannas. Small reserves, which often support higher population densities of large mammals than large reserves, play an important role in the conservation of individual species and may also retain diverse large mammal communities where modern wildlife management technique are practised.