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Sperm Whale Seismic
Study (SWSS) Chronicle 2
Special Reports from the SWSS Scientists
June 6, 2005
Prepared by Deborah Epperson
Chris Wingard
Senior Faculty Research Assistant
College of Oceanic and
Atmospheric Sciences
Oregon State University
Corvallis, Oregon
Chris is responsible
for the Simrad-60 fishery echosounder system that allows us to log
backscatter. Backscatter is an acoustic echo that results when the
echosounder sends out a sound pulse and then listens for a return.
The strength of the return indicates the size of the “target.”
Targets can be small organisms like shrimp, squid or small fish up
to something as large as a whale. Using the echosounder enables us
to determine if there are prey fields (targets) in areas where sperm
whales are also found.
 By combining these observations with
information from the visual sightings and acoustic contacts, it may
enable us to better understand sperm whale feeding behavior in the
Gulf of Mexico. Little is known about the food habits of sperm
whales in the Gulf and this technique may provide clues to both prey
size and location.
The display from the echosounder illustrates a backscatter layer at
approximately 500 meters and a backscatter trace of what we presume to
be a sperm whale under the vessel. |
