Some bat species are more likely to be found in cities than in the countryside. A scientific team from Freie Universität Berlin, the University of Greifswald, the Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) and the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) have now investigated which characteristics are typical for urban and rural bats. The team found that bat species with higher affinity to cities are characterized by relatively low frequencies and long durations of their echolocation calls, a small body size and flexibility in the choice of their daytime roost.