Fig S3. A boxplot showing the distribution of automatic
detections with increased number of singers per sound file. All examined sound
files with more than 15 detections per minute of effort, apart from one,
included two or more singers. If the detection rate exceeded 25 detections per
minute of effort the sound files included at least three singers while sound
files with more than 30 detections per minute of effort included 4 or more
singers.