LOCALIZATION OF INSECT CALLS BY THE BAT NYCTOPHILUS-GEOFFROYI (CHIROPTERA, VESPERTILIONIDAE) - A LABORATORY STUDY

Many insects use acoustic signals to attract mates but their calls may be exploited by predators. This laboratory study showed that the less er long-eared bat, Nyctophilus geoffroyi, was attracted to both (a) ca lling tettigoniids and (b) synthesised calls broadcast through loud-sp eakers. Playback experiments, using synthetic calls, demonstrated that bats were more attracted to calls of longer duration than to calls of short duration, while high calling rates and high call intensities ha d no special attraction. Two-speaker choruses appeared to be more attr active than a single speaker. These results are discussed in the conte xt of predation as a selective force on calling strategies.