send their voice into the supporting medium of air. Whales send
their songs into ocean water. One particular song, a sort of
fluttering echo, or "boing," sound first heard by human listeners in
the North Pacific Ocean in the 1950s (and recorded by US Navy
submarines) baffled scientists. Where was it coming from? Only now
have the sounds been identified as coming from minke whales.
Shannon Rankin and Jay Barlow, scientists at the National Marine
Fisheries Service in La Jolla, California, have gathered hydrophone
data in the body of ocean between Mexico and Hawaii and combined
this with visual sightings of the marine mammals. Not only has the
source been traced to minke whales, but the songs seem to be
somewhat different on either side of a certain longitude.
east, the boing sound is issued at a frequency of about 92 Hz and an
average duration of 3.6 seconds. The west boing, by contrast,
consists of a 135-Hz vocalization with a duration of about 2.6
seconds. The acoustic trace is both frequency modulated (FM) and
amplitude modulated (AM).
Rankin and Barlow,
Journal of the Acoustical Society of America, November 2005
sounds, including the boing, can be accessed on this
NOAA Web page