Habitat use and interspecific processes are key factors shaping regional distribution as well as local activity patterns of mammals. To assess the importance of differential habitat use and interspecific processes for the distribution of local activity in Eptesicus nilssonii, a critically endangered bat species in Germany, a bat detector transect survey was conducted in central Germany. One transect end was close to a maternity roost of E. nilssonii. We compared the bats' use of habitat types and the use of distance zones centred around this maternity roost. We arranged the 11 bat species detected into four foraging categories, E. nilssonii, Pipistrellus pipistrellus, larger open-space bats (Vespertilio murinus, Nyctalus noctula, Eptesicus serotinus) and narrow-space bats (Myotis species). General bat activity was highest in lake and lowest in agricultural habitats. We found significant differences in the use of habitats and distance zones between the foraging categories. However, these differences did not lead to inversed activity gradients for E. nilssonii, P. pipistrellus and narrow-space bats, and these bats were often seen to forage simultaneously at the same transect site. Open-space bats were rarely detected along our transect. We found indications that habitats and distance zones used by E. nilssonii were used considerably less by larger open-space bats. Moreover, bats of the latter foraging category were never seen to forage simultaneously with E. nilssonii. Our results provide a first indication that interspecific processes rather than habitat use may shape regional activity patterns of E. nilssonii. These interspecific processes are relevant for species conservation planning.