Simultaneous acoustic tag and seafloor acoustic recorder detection of right whale calls in the Bay of Fundy.

Abstract

Passive acoustic monitoring is playing a growing role in marine mammal detection. Determining the range of detection for calls of a particular species in a particular location is important to assess the regional coverage provided by individual recording units. This study describes the comparison of right whale calls recorded by digital acoustic recording tags (Dtags) attached with suction cups to North Atlantic right whales and the detection of the same calls using a dispersed seafloor array of autonomous recorders. The seafloor array consisted of 5 units, spaced 6–10 km apart, continuously recording from July 29– August 17, 2005. Dtags were attached to a total of 14 individual right whales during this time period and 7 of these individuals produced a total of 88 tonal calls during tag attachment. The tag and related tracking of the whale provided information on call type, and the timing, depth, and approximate location of the whale producing the call. Tagged whale calls were audible on the seafloor array, and whale-recorder distances provided estimates of the acoustic detection range for right whales in the Bay of Fundy, Canada.