Adam S. Frankel
Dept. of Oceanogr., Univ. of Hawaii, 1000 Pope Rd., Honolulu, HI 96822
Christopher W. Clark
Cornell Bioacoust. Res. Prog., Ithaca, NY 14850
Studies to determine the effects of various acoustic stimuli on whales are reviewed, with an emphasis on those studies that quantified sound level. Most of these studies have tested the effects of anthropogenic sound on bowhead and gray whales, with some work on other species. The variables used to measure the whales' response to sound typically include course deviations and changes in rates of respiration and other behaviors. Examples include the relationship of received level with the probability of avoidance of the sound source [Malme et al., MMS Rep. (1983, 1984)] and changes in respiration rate after the beginning of a sound playback [Richardson et al., Mar. Environ. Res. 29, 135--160 (1990)]. Response thresholds for continuous sounds have typically been measured at 110--124 dB, with responses to orca ``screams'' near 0 dB S/N ratio [Malme et al., MMS Rep. (1983)]. These studies have led to the use of the 120-dB level as a regulatory criterion for cetacean disturbance. The results of these studies will be presented considering which variables may be important for determining or predicting a whale's response to sound.