Differences in echolocation click patterns of the beluga (<i>D</i> <i>e</i> <i>l</i> <i>p</i> <i>h</i> <i>i</i> <i>n</i> <i>a</i> <i>p</i> <i>t</i> <i>e</i> <i>r</i> <i>u</i> <i>s</i> <i>l</i> <i>e</i> <i>u</i> <i>c</i> <i>a</i> <i>s</i>) and the bottlenose dolphin (<i>T</i> <i>u</i> <i>r</i> <i>s</i> <i>i</i> <i>o</i> <i>p</i> <i>s</i> <i>t</i> <i>r</i> <i>u</i> <i>n</i> <i>c</i> <i>a</i> <i>t</i> <i>u</i> <i>s</i>)

Abstract

In an echolocation experiment, the target detection performance of a beluga and a bottlenose dolphin were similar, but each produced different patterns of echolocation click trains. The beluga emitted three different patterns of echolocation clicks. A pattern I click train started with low-amplitude clicks, followed by packets of clicks. A packet contained several clicks with interclick intervals less than the two-way travel time to the target; the interpacket intervals were greater than the two-way travel time. A pattern II click train consisted of a combination of individual clicks, some with intervals less than and some greater than the two-way travel time. This pattern did not contain packets. The third pattern of click trains consisted of individual clicks with interclick intervals less than the two-way travel time. However, the bottlenose dolphin always emitted clicks with interclick intervals greater than the two-way travel time. These differences in click patterns suggest that the beluga has a different echolocation strategy than the bottlenose dolphin.