Roost selection and home range of an African insectivorous bat Nycteris thebaica (Chiroptera, Nycteridae)

Abstract

Roost site selection, daily movement patterns and home range area of African bats are poorly known. We used radio-telemetry to investigate these parameters in the African bat Nycteris thebaica. The bats predominantly used antbear Orycteropus afer burrows or culverts as night roosts. Day roost sites included caves and antbear burrows. Individuals travelled an average of 1.1 km between day roosts and foraging areas, a distance similar to that predicted from a comparative study of aspect ratios. Foraging (home) ranges were relatively small and averaged 12.9 ha. The foraging range of each bat overlapped on average with the ranges of 4.3 neighbouring bats, and the area of overlap covered 49% of its foraging range. For a bat with low wingloading, N. thebaica is capable of large travelling distances, suggesting that it is a strong flyer. We suggest that antbear burrows are not limiting; however, it is likely that these bats travel beyond the foraging area for more optimal roosts such as caves.