The terrestrial small mammals of the Parc National de Masoala, northeastern Madagascar

The results of small mammal inventories at 11 sites ranging from sea level to 1000 m a.s.l. on the Masoala Peninsula in northeastern Madagascar are presented. The Rodentia and Lipotyphla (ex Insectivora) of this peninsula, that contain extensive areas of lowland rainforest and some montane habitat, were previously poorly known. Fifteen endemic (5 rodents and 10 tenrecs) and 2 introduced species Rattus rattus (Linnaeus, 1758) andSuncus murinus(Linnaeus, 1766)] were recorded. Species diversity in the lowland forests was reduced as typically found in other lowland sites in the eastern humid forest, while that of the lower montane zone was notably low as compared with other nearby large forested areas to the interior of the peninsula. Several ideas are presented to explain this difference, including the peninsula effect.