Agasthya 5.3 Small mammals of the rainforest

The forests of Kakachi are a heterogeneous and complex habitat matrix. There are primary forests with towering giants, secondary regenerating patches that resemble montane sholas and regions with only the economically important canopy trees removed. Patterns of vertical stratification and canopy utilization by non-volant small mammals were analysed across this habitat. In all, eight species were recorded of which three were mainly or exclusively arboreal. The community can be classified into three groups in relation to their vertical activity. Firstly, the terrestrial shrews, mice and rats, a second group comprising scansorial species of the genus Rattus that mainly use the ground and under storey and lastly, an arboreal group of squirrels and rodents. Community composition and relative abundance of species in the different vertical strata were dissimilar, with a general reduction of species in the upper layers. Results indicate that structural changes in rain forest habitat by selection-felling and clear-felling change community composition but they do not seem to alter greatly the specific patterns of vertical habitat utilization. The White-bellied wood rat dominated the community at ground level across all habitats and malabar spiny dormouse was most often found in the canopy. These two species are important seed predators and this differential habitat utilization could be a mechanism to avoid competition. Unlike the Neo-tropics and the Orient, the rainforests of the Western Ghats are similar to the African wet forests in being species poor for non-volant small mammals, which maybe due to geographic isolation and historic habitat disturbance and fragmentation.