INTERSPECIFIC DIFFERENCES IN WHISTLES PRODUCED BY INSHORE DOLPHINS INMORETON BAY, QUEENSLAND, AUSTRALIA

The sounds produced by bottlenose dolphins, Tursiops truncatus, and In do-Pacific humpback dolphins, Sousa chinensis, were recorded on 11 day s from 3 April to 13 August 1990 in Moreton Bay, eastern Australia. Tw elve hours and 34 minutes of sound were recorded. The physical structu re of whistles was described using a variable for duration and seven v ariables for frequency. Data were subjected to principal components an alysis (PCA) and canonical discriminant analysis (CDA). PCA demonstrat ed the range of whistle contours recorded. CDA demonstrated difference s in the whistles between species. Humpback dolphin whistles differed in shape (frequency modulation) and were generally of shorter duration and higher overall frequency than those of bottlenose dolphin whistle s.