LONG BEACH, Calif. – State coastal regulators voted Wednesday to impose restrictions on the U.S. Navy's use of sonar, which has been linked to harmful effects on whales and other marine mammals.
The Navy has been using sonar during training exercises off the California coast for decades, although this was the first time it sought approval for the practice from the California Coastal Commission.
The commission voted 8-1 to place restrictions on how the Navy conducts the training, including moving the exercises away from areas with high concentrations of marine mammals and lowering sonar levels when they are present.
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The Navy decided to seek the commission's consent because of new internal guidelines requiring it to ensure major exercises are environmentally compliant.
"We believe we've taken many steps to safeguard the environment, and we feel very confident the measures that we have in place protect the environment," said Matt Brown, spokesman for the Navy's southwest region.
The secretary of the Navy will respond after reviewing the commission's recommendations.
Environmentalists applauded the commission's vote.
"The commission fulfilled its mandate from the people of California to protect our coast," said Cara Horowitz, an attorney for the Natural Resources Defense Council, which filed a federal lawsuit in Los Angeles demanding the Navy develop a mitigation plan for the exercises.
The Navy conducts sonar-training runs in all its operational waters including the East Coast, the Gulf Coast, Hawaii and the Pacific Northwest.
Sonar, or pulses of sound, are used to track submerged objects — a key technology for finding enemy submarines.
The Navy's sonar exercises have been responsible for at least six cases of mass death and unusual behavior among whales in the past decade, a U.S. Congressional Research Service report found last year. Many of the beached or dead animals had damaged hearing organs.
In recent years, strandings have occurred in the Bahamas in 2000, the Canary Islands in 2004 and in North Carolina in 2005.
Sonar is also believed to affect other marine life including fish reproductive rates and the behavior of giant sea turtles.
Last July, a federal judge issued a temporary restraining order to block the Navy from using sonar during training in Hawaii. The NRDC, which sought the injunction, argued scientific evidence showed sonar can fatally harm marine mammals.
Both sides eventually settled, and the Navy agreed to stay away from certain sensitive marine habitats and increase whale monitoring in Hawaii.
Since then, however, the Navy has said the steps were often unnecessary, hindered training and in some cases weren't based on fact.