Sperm Whale Seismic Study (SWSS) Chronicle 3

Special Reports from the SWSS Scientists

June 9, 2005

Prepared by Dr. Deborah Epperson
Acoustic Team
Minerals Management Service
 

Dr. Aaron Thode, Associate Researcher
Scripps Institute of Oceanography
University of California - San Diego

Figure 1

Acoustic monitoring is a critical element of the SWSS program. Whales and dolphins rely heavily on sound for communication and sperm whales are no exception. Sperm whales produce intense clicks that may be used for communication or possibly echolocation and which likely assist the whales during feeding, socializing, and other important natural behaviors.  These "clicks" can be heard with a towed hydrophone array (See Figure 1).

Figure 2

On the R/V Gyre, we are towing 2 hydrophone arrays that are monitored 24 hours a day even in bad weather. By using computer programs it is possible to determine numbers of whales and their locations relative to the ship (See Figure 2).

Figure 3

These data are used by the acoustic team to pinpoint sperm whale locations. During daylight hours the acoustic data are communicated to the visual team on the flying bridge and used to direct the tag boat to the whales (See Figure 3).

At night the acoustic team is responsible for keeping the ship with the whales. Acoustic monitoring provides researchers with "ears" in an otherwise inaccessible environment.