A method of independent time and frequency decomposition of bioacoustic signals: inter-individual recognition in four species of penguins.

The aim of this paper is to introduce a method for analyzing acoustic signals capable of assessing the potential for individual coding information. Signals are analysed both in the time domain (rhythm of emission of the song independent of its frequency content) and in the spectral domain (spectral content of the song independent of the rhythm of emission). The method is then applied to a comparative study of four penguin species, where the problem posed by inter-individual recognition differs from species to species. A direct relationship was shown between the potential of individual coding and the difficulty in partner identification.