The California Coastal Commission, concerned that the U.S. Navy's use of sonar poses potential dangers to whales, dolphins and other sea creatures, voted Wednesday to allow the military to continue its training exercises in Southern California but imposed strict controls to protect marine life.

The commissioners, before an 8-1 vote, said they believed the Navy could train personnel if it took precautions with high-powered sonar, explosives, mine drops and missile launches from ships, submarines, helicopters, airplanes and amphibious vehicles.

At the meeting, Navy Adm. Lyn Hering said he couldn't agree to the state's imposed conditions without approval of the secretary of the Navy.

The Navy can agree to the state's action or inform the state that it chooses not to meet some of the conditions. The state could then argue in court that the military was threatening resources protected by state law. If the state wins, the Navy could get relief only from the president.

For decades the Navy has trained at San Clemente Island, the most southern of the Channel Islands, and at Camp Pendleton. The military probably has been using the midfrequency active sonar technology for about 50 years.

Naval officials have said that they don't intend to intensify their activities.

Sonar, the underwater equivalent of radar, uses sound to locate an object and determine the speed at which it's traveling. Scientists believe marine mammals depend on sound to navigate, find food, locate mates, avoid predators and communicate. Flooding their habitat with man-made, high-intensity noise interferes with their lives in the ocean, experts say.

Wednesday's vote was the result of the first major review by the commission of environmental effects of the Navy's military training, which occurs in the region offshore of San Diego. The federal Coastal Zone Management Act allows states to decide if federal activities are consistent with state laws.

The Navy has promised to conduct most of its sonar activities 80 miles offshore, and said it would limit explosive charges to 5 pounds in near-shore waters.

The commission, however, voted unanimously in December to ask the Navy to do more to limit potential harm to wildlife. Gray, blue and humpback whales, dolphins and porpoises live in California waters.

The commission members had concerns over midfrequency active sonar because there have been several stranded whales in the Bahamas, Puget Sound, Alaska and Hawaii at the time of naval training activities over the past six years.

Commissioners Sara Wan and Meg Caldwell, along with underwater acoustic scientists, as well as the nonprofit Natural Resources Defense Council, pressed for strong protections at the meeting in Long Beach.

"I believe that the Navy could go ahead with its exercises and do these mitigations. Most are taken from things, in one way or another, that the Navy has done,'' Wan said.

Some of the conditions placed on the Navy include:

-- Ensuring that midfrequency active sonar won't reach whales and other marine species at levels higher than 154 decibels, a precautionary number recommended by Woods Hole Oceanographic Institution, unless the Navy could show in what cases it wouldn't be possible. The Navy wanted to use the benchmark of 190 decibels but had agreed to the National Marine Fisheries Service recommendation of 173 decibels.

-- Avoiding, where possible, effects on gray whales, which travel twice a year close to the coast between their winter habitat in Baja California and summer habitat in the Bering Sea and Arctic region.

-- Staying away from natural underwater configurations such as seamounts that support sea life.

-- Dedicating two observers trained by the National Oceanic and Atmospheric Administration to monitor the use of sonar.

-- Protecting loggerhead shrikes, island night lizards and snowy plovers on land during amphibious landing activities at San Clemente Island and other activities at Camp Pendleton.

• San Francisco Chronicle

• Re: Strict rules for Navy's use of sonar off coast Mike 05:56:52 01/12/07 (0)