Small Mammal Inventories in the East and West Usambara Mountains, Tanzania. 1. Study Areas, Methodologies, and General Results

Abstract

The Eastern Arc Mountains of southeastern Kenya and Tanzania hold a rich and unique biodiversity. The most celebrated of these mountains are the East and West Usambaras. Although these massifs have been the subjects of biological study for over a century, little is known about the shrews, bats, and rodents occurring in the montane forests. Using pitfall buckets, small mammal traps, and mist-nets, between 1991 and 1993, we surveyed the small mammals in the Amani area in the East Usambara and Ambangulu area in the West Usambara to document the natural history of the local fauna. These surveys were conducted during the dry season annually between early July and early September.In this chapter, we outline the study sites, methodologies, capture rates, and other trapping details. A total of 18,563 sample-nights was accrued over the three-year study, and on these two massifs, we documented 12 crocidurine shrew, one macroscelidid elephant shrew, 19 bat, and 14 rodent species. Species accumulation curves suggest that additional trapping effort may be required in the East Usambara Mountains to have a more complete view of the local small mammal fauna. There was no significant difference in the number of individuals captured or measures of species diversity in the pitfall and trap lines that were installed in the same location during the course of this study, suggesting that repeated sampling did not negatively affect the small mammal fauna of the study areas.