Click Structure in the Porpoise, Phocoena phocoena

Abstract

The phonation of Phocoena phocoena consists of low intensity, narrow-band clicks usually near 2 kilohertz, produced singly or in bursts at repetition-rates as great as about 1000 per second. the higher repetition-rates show as harmonic bands in spectral analysis when relatively narrow analyzing filters are used. Many clicks contain variable emphasis at discrete higher frequencies. the correct name of this species is discussed. We found no evidence of regional variation in phonation (“local accent”) in either P . phocoena or any of several other cetacean species.