Testing the Waters (continued)
April 30, 1999
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The Navy's 36-ton LFAS system is a 57-meter block of 18 speakers. It can potentially assault hundreds of thousands of square miles of ocean with sound. It transmits LFAS signals approximately four billion times louder than the volume scientists already know whales will swerve to avoid. And because LFAS is specifically designed to maintain its force over a great distance, it can be audible from thousands of miles away.
In 1996, facing the threat of litigation by the NRDC, the Navy agreed to prepare an Environmental Impact Statement (EIS) before going ahead with the deployment. It is the first EIS the Navy has ever prepared for a new technology system of any kind, according to the NRDC. This landmark document is now complete, and the Navy expects to publish a draft for public comment within the next eight weeks.
Although publication of the EIS will be a symbolic victory, over at the NRDC there is no champagne on ice. With many of the study's findings already published or leaked, it is no secret that the Navy will publicly conclude that it can "safely" deploy LFAS. Naturally, opponents are skeptical. They say the Navy's tests were grossly inadequate. Of particular concern is the long-term effect of LFAS on marine mammals, which even the EIS researchers admit they haven't studied.
Nevertheless, LFAS opponents will have their work cut out for them challenging the integrity of the EIS. The Navy hired some of the world's leading experts on marine mammals and sound to conduct the research. Dr. Christopher Clark of Cornell University and Dr. Peter Tyack of Woods Hole Oceanographic Institute lead the team.
The team conducted three phases of research from September 1997 through March 1998 off the coasts of California and the Hawaiian islands. The team watched each area's whale population for any signs of strange behavior in reaction to LFAS sounds from 120 decibels, a level previous studies have shown whales avoid, to 155 decibels, the maximum level to which researchers felt they could safely expose the whales. While acknowledging that some whales did react to LFAS by changing direction or temporarily ceasing to sing, the team didn't think these responses indicated harm being done. Neither did they observe "significant biological impact" on any key activities, such as breeding, nursing, or feeding. Tyack did say, however, that disruption of whale singing can possibly affect breeding.
"We did see detectable changes. We did find animals in that region [that] stop[ped] singing," says Tyack, "But within half an hour they would adjust." He felt LFAS wasn't any more of a disruption than other human-made sounds, such as those of passing motor boats.
