Scientists interested in standards for anthropogenic noise impacts on marine
mammals may wish to consider the default standards that may be established by
the Environmental Impact Statement for the US Navy's Undersea Warfare Training
Range, the Draft of which is currently open for public comment until 30
January 2006. The outcome of this process is likely to influence the broader
acoustic criteria now being developed by the National Marine Fisheries Service.
190 dB re 1 µPa²-s is considered the threshold of significant behavioral
disturbance for all cetaceans (DEIS page 4.3-24). This impact threshold was
derived from subjective observations of "altered behavior" during Temporary
Threshold Shift (TTS) experiments with captive dolphins and belugas at the US
SPAWAR lab, and is used to define Marine Mammal Protection Act Level B
harassment. All dB values are as received, and include a factor for duration of
190 dB re 1 µPa²-s is the received level at which beaked whales are
considered behaviorally disturbed, and as a special case, considered
injured, MMPA Level A Harassment. This value is defined as receiving a single
ping, is based on selective data, and is considered conservative (4.3-30
through 32). Do you agree with the DEIS discussion of various theories and data
relating to induced behaviors leading to injury in beaked whales? Do you know
additional references and data that might apply?
195 dB re 1 µPa²-s is defined as the onset of TTS in all cetaceans, and
establishes MMPA Level B physiological harassment. The single value onset-TTS
all cetaceans was derived from very few experiments with highly conditioned
captive bottlenose dolphins and belugas (4.3-6. and 12+).
215 dB re 1 µPa²-s is the threshold for Permanent Threshold Shift (PTS), the
onset of injury for all cetaceans (expect beaked whales), and MMPA Level A
Harassment. PTS was extrapolated from the onset-TTS assumptions and research on
terrestrial mammals including humans (4.3-15 to 18).
Comments on the DEIS for the Undersea Warfare Training Range must be
postmarked by 30 January 2006. Comments must be sent to: Naval Facilities
Command Atlantic, Attn: Mr. Keith Jenkins (Code EV21KJ), 6506 Hampton
Boulevard, Norfolk, VA 23508, Fax: 757-322-4894. The USWTR DEIS may be
Please consider whatever time you can give to this as a gift to whales.
William W. Rossiter
Cetacean Society International
P.O.Box 953, Georgetown, CT 06829 USA
ph 203-770-8615, fx 860-561-0187