Island Voices
Navy's sonar program is safe
By Joseph S. Johnson
Environmental impact statement program manager for the Navy's LFA project
The Navy can safely and effectively manage low-frequency active sonar without hurting the environment, top marine biologists say.
There is an immediate and fundamental national security need for this LFA sonar: the detection and tracking of quieter, more sophisticated foreign submarines that may threaten national security.
Currently there are 224 submarines operated by non-allied nations and approximately 500 non-U.S. submarines worldwide. LFA is the only system capable of providing reliable and dependable long-range detection.
Because marine animals can also hear low-frequency sound over long ranges and because there was little information available in 1996 to estimate how marine mammals would react to LFA signals, the Navy commissioned a study by a team of distinguished marine biologists and bio-acousticians. This effort involved complex data collection with the marine mammals considered to be most susceptible to low-frequency sound: baleen whales.
Specifically, the scientific goal was to determine whether marine mammals exposed to LFA signals would exhibit biologically significant behavioral responses. The blue, fin, gray and humpback whales studied were selected as indicator species and used scientifically to extrapolate the results to other species of lower low-frequency sensitivity.
Contrary to accusations made recently in these pages, LFA sonar has not been involved in any marine mammal strandings or injuries, and certainly not any deaths. Specifically:
• Allegations regarding incidents in Greece and the Bahamas implicate mid-frequency sonars and not LFA. In fact, during those periods, the only LFA sonar ship was in the Pacific Ocean conducting passive-only operations.
• Whales did not leave the area prior to their normal departure period. This was validated by aerial surveys conducted by a research scientist from the University of Hawai'i.
• A scientific team conducting research off the Big Island did investigate allegations of abnormal marine mammal behavior and an injury to a snorkler. The local National Marine Fisheries Service representative and a UH scientist also assisted the Navy team. The reported diver injury is contradictory to medical evidence developed during a four-year diver research program.
The reported LFA signal is similar in exposure level and sound to the songs produced from nearby male humpback whales. To our knowledge, no one has ever been injured from exposure to a humpback whale song, regardless of the proximity or level.
Several other anti-LFA proponents also claimed to be injured by emissions from LFA on March 8, 1998. Interesting, because the LFA system was not transmitting that day.
The Navy recognizes that the potential impact of man-made sound in the ocean is of public and scientific concern. The Navy cares about the ocean habitat, and its efforts are directed toward that goal. The environmentally responsible deployment of the LFA sonar system is an important Navy priority.
The final environmental impact statement supports a position that LFA sonar can be operated safely relative to both human and marine life by restricting where and when it operates and by using validated mitigation measures.
The Navy has relied on a group of independent scientists from respected institutions such as Woods Hole Oceanographic Institution and Cornell University. These are internationally recognized experts in bio-acoustics and animal behavior. Their reputations are based on many years of impeccable research and personal scientific integrity. They are truly interested in scientific fact, not emotional clamor.
The facts demonstrate that LFA sonar can be safely used in our oceans.
