Bat Functional Diversity along the Chobe River Floodplain, Botswana

Abstract

Insectivorous bats are vital components of tropical and subtropical ecosystems in Africa. However, they are not only threatened by habitat fragmentation, agriculture and urbanization but are also difficult animals to study. During 2014, we used acoustic monitoring to assess the activity and relative abundance of three functional guilds of insectivorous bats at eight sites along the Chobe River floodplain, Botswana. The activity of clutter and clutter-edge foragers was significantly higher in the dry season than in the wet season. By contrast, open-air foragers, which typically forage above or away from vegetation, were more active in the wet season than in the dry season. We believe that the availability of natural vegetation and the variability in the detection of the three bat functional guilds by our acoustic detectors likely explain our results. Although bats are volant animals, our study points towards the importance of conserving important structural vegetation elements along the Chobe River floodplain landscape. Large river systems in Africa, such as the Chobe River, are vital for insectivorous bat persistence, and the provision of the ecosystem services they provide. As such, conservation of riparian corridors along rivers is crucial for maintaining intact and diverse bat communities.