Seasonal Food Habits of Five Sympatric Forest Microchiropterans in Western Madagascar

Abstract

We determined the foods habits of 5 species of microchiropteran bats (Hipposideros commersoni, Triaenops rufus, Triaenops furculus, Myotis goudoti, and Miniopterus manavi) in the austral winter and summer in a dry deciduous forest in western Madagascar using fecal analysis. We also assessed food availability and bat activity in 4 forest microhabitats. Despite overlap in dietary composition, H. commersoni consumed mainly Coleoptera; M. goudoti consumed mainly Hymenoptera, Neuroptera, and Araneae; M. manavi consumed mainly Hemiptera; and T. rufus and T. furculus consumed mainly Lepidoptera. Diptera were the most abundant insects in traps but were rarely encountered in feces. H. commersoni was not netted during the austral winter, but the other 4 species changed their diet according to seasonal availability, with lepidopterans the most important diet items in winter and coleopterans in summer. We consistently trapped a higher abundance of potential bat prey at the forest edge, whereas the forest interior was low in both food availability and bat activity. The 5 microchiropterans studied partitioned the available food mainly through dietary specialization, although spatial and temporal partitioning also may play a role. More research is needed to assess levels of dependency on forest by these bats, and to investigate the seasonal ecology of H. commersoni and interspecific competition between T. rufus and T. furculus.