Ecology of small mammals in tropical forest habitats of southern India

Five species of rodent (Rattus rattus wroughtoni, Mus platythrix, Funambulus tristriatus, Cremnomys blanfordi and Golunda ellioti) were live-trapped over a period of eight months in three different habitat types (moist evergreen forest, moist deciduous forest and teak plantation) in Anaimalais Wildlife Sanctuary, Tamil Nadu, India. Small mammal densities ranged between 16.3 individuals ha(-1) and 20.7 ha(-1) for the natural forest sites and were 10.4 ha(-1) in the teak plantation. Moist deciduous forest had the highest species richness and diversity scores. Although the teak plantation site had the same mammal species richness as the moist evergreen forest, numbers of individuals and overall small mammal biomass in the plantation was far lower than on the natural forest sites. Compared to moist deciduous forest, species richness and diversity were significantly lower on the teak plantation. R. r. wroughtoni and M. platythrix were the two most common species captured on all three sites. R. r, wroughtoni was the most common small mammal species captured, reaching densities of 14.5 ha(-1) in moist evergreen forest. G, ellioti was the least common species, present only in moist deciduous forest. Demographic patterns and microhabitat selection were examined for R. r. wroughtoni, M. platythrix, and F. tristriatus. Only M. platythrix appeared to show any distinct seasonality in reproduction, with an increase in capture of breeding individuals towards the end of the wet season. Discriminant analysis did not reveal any distinct microhabitat preferences for any of the species. However, R. r. wroughtoni showed a significant association with bamboo, and F. tristriatus was associated with areas of higher canopy height and density in moist deciduous forest.