A Comparison Among the Calls of Four Penguin Species

In this paper we analyze the calls of four penguin species (Aptenodytes patagonica, Eudyptes chrysolophus, Pygoscelis papua, P. antarctica) recorded in the Antarctic.　We analyze the sonogram and power spectrum of the calls and make a comparison among different species in call duration, maximum frequency, minimum frequency and peak frequency. When comparing the temporal and spectral characteristics of their calls we found out that these four species have obvious interspecific variation in the call structure, making it possible for different species to distinguish each other by vocalization. Our results also indicate that the structure of the calls of Aptenodytes patagonica — a non-nesting species, is more complex than that of the other three nesting species.