Underwater recordings of Weddell seal calls recorded as a indication of male attributes, both inter and intra-sexual interactions during the breeding season in Weddell seals

To examine the call function, with respect to intra and inter sexual activities, under water playback and video monitoring techniques were used. Two playback experiments were conducted. 1) The responses of males and females to the playback of each major call type and a control sound (walrus) was examined by recording change in position relative to the underwater speaker, vocal responses, activities near the playback speaker and changes in the heart rate of tagged seals. 2) Male-male competition and inter-sexual call function was examined by overlapping the long trill call (overlapped, partially overlapped and preceded by the recorded long trill call of an unfamiliar male) of rival males and recording presence and response of both males and females occurring near the speakers.

Underwater cameras captured responses on video to playback for future analysis.