Abstract:
Typical habitats of the dipper Cinclus cinclus are rapid brooks and small rivers of the mountains, characterized by a steady noise of the fast-flowing water. This background level has a masking effect on the dipper song. At a distance of 5m the average SPL of the dipper song decreases to the 60 dB level produced by the water, and the song is getting increasingly masked. To compare the frequency spectra 1/3 octave analyses were carried out on dipper song and background noise. The spectrum of dipper song does at least somewhat contrast with that of water noise. The songs are not suitable for long-range communication but rather seem to serve pair-bondage.