Figure 4
From: Fewer bat passes are detected during small, commercial drone flights
Visual comparison of signal detection range with ambient noise and UAV noise interference. Shading represents noise amplitude from low (green) to high (red). Panels inside the blue zones (A,C,E,G) represent samples taken under ambient noise interference, while panels inside the red zones (B,D,F,H) represent samples with UAV noise interference. Distance indicators represent the distance of the detector from the loudspeaker broadcasting ultrasounds. Bats present in our study area had calls typically between 25 and 80 Hz.
