In bats, vision plays a role in various contexts, particularly for long distance orientation and the detection of food. However, the extent to which vision is used is still poorly known. Here we test whether conspicuous visual cues increase the performance of the brown long-eared bat
Plecotus auritus in an experimental paradigm based on tree hole discovery by bats. We used experimental logs with bark 'stripped off' (conspicuous bright area around entrance) and with bark 'not stripped off' to investigate whether there were differences in effectiveness of finding
the entrances with or without light. Results indicate that the bats' effectiveness in finding the stripped entrances increased when light was provided. We suggest that the entrance was more visible due to high contrast between bark and wood. Our results indicate that visual cues could play
a role in preselection of roost sites for this species.