Jean-Michel Cousteau Speaks...
off on high power military sonars:
When diving with dolphins in the Caribbean Sea, I am always amazed by their excited "chatter" as they go about their business, working together hunting for fish. It is a privilege to experience this sound, emanating from a highly evolved sonar system these animals depend on for survival.
I've often been puzzled by why these highly evolved creatures, with this complex sensory system, strand ashore in certain locations around the world, especially over the last decade.
Sadly, the answer may be that certain artificial sounds, produced by humans to monitor and track covert military activity in the ocean are responsible for certain stranding incidents, proving to be deadly for several different whale species in specific locations such as the Bahamas. Mounting scientific evidence shows acoustic signals from high power military sonars can and do cause harm to ocean life - biological damage such as behavioral changes, brain injuries, and, in some cases, death.
On March 15, 2000 the Navy conducted a Low Frequency Active Sonar (LFA) exercise in the Bahamas, emitting high-energy, low frequency sonar at between 215 and 235dB, creating powerful sound and pressure waves through the water. Sound at 235dB produces a pressure wave 300,000 times more intense than a 180dB sound, and 100 billion times more intense than a 120dB sound, which is like a loud motorboat engine. LFA is one of several complex underwater sonar technologies tested by the Navy and NATO at various sites around the world to detect submarine activities of other nations.
that fateful day in March, four species of whales and
dolphins (at least 14 animals) stranded along shores of
the Northeast and Northwest Providence Channel, which is
between Nassau/Eleuthera and Grand Bahama/Abaco. At least
7 mortalities were confirmed on that day.
It is important for us to learn more about LFA and other far-ranging sonar systems being developed to protect our national security. We need to better understand the consequences of sonar testing on the marine environment and on cetaceans, whose very lives, ironically, depend on their own highly evolved sonar system. We need to consider the ethical implications of continuing to conduct this research in light of the fact that dead and dying whales have been found coincident with tests and exercises employing military sonars. And, we need to question the Navy's reasoning for using this technology when the welfare of marine mammals, some of which are endangered, is at stake.
The Bahamas stranding incident is now providing us clearer answers based on scientific data. An Natural Resources Defense Council (NRDC) report describes the Bahamas event as undeniable evidence indicating high-power military sonar systems can and do kill marine mammals.
"An investigative report released by the Navy and the National Oceanic and Atmospheric Administration has established with virtual certainty that the mass mortality was caused by a Navy battle group using mid-frequency range active sonar in the vicinity. Although active sonar has been suspected in previous whale beachings, prompt analysis in this case of the dead whales enabled scientists to confirm, for the first time, the lethal role of the sonar system."
Further intensive analysis on one of the stranded beaked dolphins, (including CAT-SCAN testing conducted at Harvard University) by Kenneth C. Balcomb, III with the Center for Whale Research, (on site during the Bahamas mass stranding documented) "the killing is largely due to injurious resonance phenomena created by the U.S. Naval sonar system in the whales' cranial airspaces, tearing apart delicate tissues around the brains and ears." The mass strandings in the Bahamas "conclusively demonstrated the lethality of high-powered sonars, and it provided the opportunity to understand how sonar has been killing whales in vast expanses of ocean around the world."
Balcomb, in his review of the Navy's Final Overseas Environmental Impact Statement and Environmental Impact statement for SURTASS LFA (January 2001) further stated that "resonance with LFA and sonar frequencies is a problem for beaked whales, the sound pressure level of 180 dB RL is demonstrably "dangerous", for other cetaceans (two minke whales and a bottlenose dolphin were involved in the Bahamas mass-strandings.) Aversion and/or physiological damage evidently and repeatedly occurs in beaked whales at levels somewhere between 150 and 180 dB RL (probably nearer the former) of either low frequency or mid frequency sonar signals in the whales' former habitat."
In other parts of the world, high power military sonar testing and exercises over the last decade are highly suspect in causing negative behavioral changes, stress and injuries to cetaceans in the vicinity of the deployment zone. Consider the following consequences following military sonar testing events:
· Sometimes whales fall silent. Sperm and pilot whales stopped "singing" (using their active sonar) altogether during a 220 decibel test in 1991, some of them for days, which meant they stopped eating during that time.
The U.S. Navy intends to operate this system over 80% of the world's oceans. Before LFA can be further tested in the waters off California, they must gain approval from both the California Coastal Commission and National Marine Fisheries Service. While I respect this military organization and their duty to protect the security of this great nation, I find the deployment of high power acoustic sonars morally and ethically unjustified. There is now conclusive scientific data that shows the current design of these sonars causes short-term effects proven lethal to whales and dolphins at a level far less intense (180dB) than that planned for a globally-deployed LFA sonar (up to 235dB). There is zero conclusive data on LFA's long-term effects on baleen whales, beaked dolphins, other cetacean species or entire marine ecosystems and their inhabitants.
I think anyone who spends time in the sea, swimming, snorkeling or diving, will agree with me that the sea is filled with fascinating natural sounds. They can be as familiar as one's own breathing, strange, as in the case of the crunching noise produced by tropical parrotfish dining on coral, or wild and exotic, as are the squeals and clicks from dolphins using echolocation to hunt for fish. These are natural sounds that belong in the undersea world. But, we must stop using harmful human-induced sound waves from high power sonars until their effects are better understood. We must act quickly for the sake of marine creatures that enrich the oceans and in turn, enrich our lives.
You can take action on the LFA issue by:
Learn more! Click here to review questions and answers about LFA and Marine mammals.
Click here for a list of references and resources with up-to-date information you can access to help you discover the effects of high power military sonar.
Join me in being a "voice for the ocean!" Click here to become an Ocean Futures member now - it's easy and it's free
Let your voice be heard now! Write the Secretary of the Navy your local Congressional representatives, the California Coastal Commission and the National Marine Fisheries Service. Ask them to end the Navy's Active Sonar program. Click here to send your ACTION E-LETTER now.
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Updated March 22, 2001