Recordings made at the Domänetal near Kiel. Sampling and display curtesy of the Shareware Cooledit96.
The display shows the volume of the calls. The volume depends among others on distance and orientation of the bat (towards or away from recorder). The frequencies used by the bat cannot be reconstructed from these recordings.
At 2,2s the calls made by a bat to locate prey closeby can be heard (location call). On the other hand, orientation calls are as a rule regular, being co-ordinated with the wingbeat. (Recording made at appr. 44 kHz).
Download WAV-File (221k): zwerg.wav
Several N.n. are hunting in appr. 10 m (multiply by 3 for ft) above a lake. At 2,3s the call for locating prey closeby can be heard. Lower volumes from N.n. flying further away. (Recording taken at appr. 25 kHz).
Download WAV-File (163k): abend.wav
Several M.d., probably 4, hunting close above the lake. Wind may have driven insects flying above the lake to one end, causing the bats to follow their prey. (Recording at appr. 44 kHz).
Download WAV-File (170k): wasser.wav