Investigations on Cetacea (1970)


An audiogram has been obtained from the harbour porpoise, Ph.phocoena, in water from 1 to 150 kHz by using the operant conditioning technique. The highest sensitivity was measured between 8 and 32 kHz equal to about 10^-17 Watt/cm2 Between 140 and 150 kHz the sensitivity falls off 50 dB – equal to about 700 dB/octave. The audiogram plotted for this species agrees fairly well with the audiogram of the bottlenose dolphin, Tursiops truncatus.