Long distance calls: Negligible information loss of little auk social vocalisations due to high frequency propagation losses
Fig 5
A sample classic call attenuated to mimic signal structure at 10 exponential distances in a range of 1–1000 m.
Notice that the signal remains very stable, and harmonics are only lost at extreme distances. Note that to improve readability, the spectrograms are not plotted on the same scale, and the colours should not be interpreted as comparable between the panels. Spectrograms plotted using the seewave package [12].