SWSS Chronicles Special Reports from the SWSS Scientists
Chronicle
3 - 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
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).
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).
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.
