Whales Vs. US Defense?
Navy wants to use special sonar to track submarines, but it may harm marine life.
HONOLULU — The sound and fury off the coast of Hawaii signifies everything to environmentalists and the United States Navy.
To the Navy, a sonar system designed to detect quiet submarines is a crucial link in America's protection against submarine-launched missiles. To environmentalists, however, the high-volume low-frequency sound waves that travel for long distances are a potentially deadly acoustic assault on sensitive marine animals.
It's an ecological donnybrook that pits whales' tolerance for loud noises against America's national defense. But it is only the latest chapter in an ongoing battle between environmental activists and researchers and the military over the effects of man-made ocean noises on marine life. What concerns environmentalists about new projects like this one is that they would create constant underwater noise - a barrage activists say will have disastrous long-term effects on animals that rely on their sense of hearing for everything from locating food to finding prospective mates.
The battle lines were first drawn in 1994 when scientists from the Scripps Institute of Oceanography in San Diego, Calif., announced a plan to broadcast loud sounds at regular intervals from speakers off the coast of Big Sur, Calif., and the Hawaiian island of Kauai. The project, called Acoustic Thermometry of Ocean Climate (ATOC), used sound waves to check ocean temperatures in an effort to track global warming.
Since then, the Navy has tested its sonar, known as Low Frequency Active (LFA) sonar, three times - most recently off Hawaii in February. (Previous phases tested the sonar's effect on gray whales, blue whales, and fin whales off the coast of California.)
Designed to study whale reactions to the LFA, the experimental series drew intense criticism many environmental groups. Several of them - including Greenpeace, Earth Island Institute, and the Ocean Mammal Institute - filed a lawsuit to stop the tests, claiming the Navy needed to file an Environmental Impact Statement and give more information about the tests. Civilian scientists involved in the project countered that the tests were designed not to harm whales and, in fact, would not expose whales to sounds louder than their own calls.
US federal courts on several occasions ruled in favor of the Navy, but protesters succeeded in shortening the experiments when they hurled themselves into the water near project vessels.
The tests' effect
While the tests are over for now, the effect on the whales is still unclear. Environmentalists claim that the LFA and ATOC tests have already had disastrous consequences, including four dead humpbacks sighted in California and Hawaii during the ATOC tests.
Meanwhile, during the Hawaii LFA tests, Greenpeace Hawaii claimed humpbacks fled the test area, forcing whalewatching tour boats on the Kona Coast to halt operations. And in a March letter to the respected science journal Nature, a team of Greek marine scientists claimed there was a link between whale beachings and LFA tests by NATO in the Mediterranean in May 1996.
Marsha Green, a marine scientist and environmental activist with the Ocean Mammal Institute, claims that at least one humpback calf was abandoned by its mother. "In my 10 years [of research] I have never seen a lone calf. No one I know has seen a lone calf," says Dr. Green, who notes that the researchers were being paid by the Navy. "More than 50 percent of marine-mammal funding in the US comes from the military," she adds. Furthermore, Green says the actual operational sonar will likely be louder than the 200 decibels used in the LFA tests - a fact acknowledged by the Navy.
But according to scientists involved in the experiments, there have been no reports of significant negative effects as a result of either ATOC or LFA tests. "We didn't see any reduction in calling rate by humpback whales, even when they were close to the source," says Kurt Fristrup, a bioacoustics researcher with Cornell University who was part of the civilian LFA scientific team.
Dr. Fristrup says he had reservations about the tests and is still waiting to see the final analysis of the data, but "we had singers that were calling actually approach the vessel and continue calling with their song." And Fristrup points out that, "in terms of overall human impact, LFA takes a back seat to shipping noise and marine exploration technologies."
New noise pollution
Indeed, modern developments like shipping traffic, oil exploration and drilling, and geophysical mapping efforts have made the deep far from silent - and in places downright noisy. Supertankers under steam emit sounds close to 200 decibels, almost as much as the sound of a revving jet engine. Other equipment used in oil exploration and ocean-bottom mapping make sounds even louder than that.
Despite these initial assurances of researchers, however, environmentalists are intent on stopping both future LFA tests and the system's deployment. "There is not enough knowledge to understand what the long-term impacts of the LFA system are going to be on marine life," says Donna Harvey of Earth Justice Legal Fund.
Regardless, the oceans will likely get noisier and noisier. Shipping traffic and other forms of man-made noise will increase in coming years as the world economy grows. The Scripps Institute team performing the ATOC tests is hoping to put boom boxes around the globe to expand the experiment. And the Navy is clearly moving ahead with deployment of LFA sonar.
For their part, the project scientists say the jury is still out on LFA, but they say experiments like the one off Hawaii are vital to making informed decisions. "I think the long-term consequences of ignorance would be much greater than the possible effects on animals in smaller scale experiments," says Fristrup.