Underwater vocalizations of leopard seals (Hydrurga leptonyx) and crabeater seals (Lobodon carcinophagus) near the South Shetland Islands, Antarctica

Four underwater vocalizations of leopard seals (Hydrurga leptonyx) and one from the crabeater seal (Lobodon carcinophagus), representing most of their vocal repertoires, are described quantitatively and illustrated with sound spectrographs. Most of the underwater vocalizations given by these seals can now be identified, which will facilitate future investigation of possible geographic variation. Coupled with further studies of diurnal and seasonal variations in seal vocalizations, underwater recording may be used to study sub-ice distribution and possibly relative abundance.