Microgeographic variation and songs in the underwater vocalisation repertoire of the Weddell seal (Leptonychotes weddellii) from the Vestfold Hills, Antarctica

Abstract

Recordings of underwater vocalisations of the Weddell seal (Leptonychotes weddellii) were made in fjords of the Vestfold Hills near Davis Station, Antarctica. The repertoire was examined for the presence of microgeographic variation. Recordings covered the period from the end of mating to the beginning of the moult in the 1989/1990 breeding season. The repertoire was classified into 44 vocalisation types using a classification method based on objective parameters. Unique vocalisations were identified at each site, with 48% exclusive to Long Fjord and 41% to Tryne Fjord. A small percentage (11%) of the repertoire was common to both fjords reflecting the limited, observed interchange of individuals between these populations due to their strong breeding site fidelity. Seven male songs are described in the present study and possibly function to maintain underwater territories.