Description: The 20-Hz signals of finback whales are perhaps one of the better described whale calls in the Atlantic Ocean. Typically, these signals are short (< 1s) pulses that downsweep from about 23 Hz to 18 Hz. These pulses typically are produced in groups or "bouts"(Watkins et al. 1987). Pulse duration, frequency and bout length can vary with location.

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162K wav file(The recorded signal has been sped up 10 times)