Loud Impulse Sounds in Odontocete Predation and Social Behavior

Abstract

Norris and Møhl (1983) presented the hypothesis that odontocete cetaceans might be able to debilitate prey with intense sound and presented evidence to stimulate observation and experiment on this topic. This paper outlines our research on the hypothesis since its original proposal and extends the hypothesis by suggesting that dolphins can produce loud impulse sounds of low median frequency and long duration which might disorient prey. Sounds of 500 Hz to 5 kHz fall into the range of hearing or labyrinth sensitivity of prey species and the long duration (to 200 ms) could cause overloading of the unprotected fish ear.