The largest animals the earth has ever known, blue whales, are endangered, mysterious and legally protected. So when the 73-foot-long body of one washed ashore near Fort Bragg last month, scientific and media attention focused on the massive carcass, overshadowing the question of just what caused the whale's death.

"What I've been told," says California Coastal Conservancy and Ocean Protection Council staffer Shelia Semans, "is that when blue whales are feeding, their throats expand to nearly twice the size of their body, and when they're surfacing with their mouths completely full of water and krill and small fish, they don't see well and they're not agile. So if they come up at the back of the boat where the propeller is, there's a good chance they wouldn't even see it."

Semans manages the seafloor mapping project on which the Pacific Star was working when it hit the whale Oct. 19. The 176-foot survey vessel—much larger than has been widely reported—was moving slowly, around five knots, and "did not hit the whale," Semans stresses. "All the impact was in the back where the propeller was."

After examining the fatal wound, she says the investigators concluded that "the whale came up into the prop, and the propeller severed the whale's spinal cord," causing it to bleed to death. "It was very clear what the injury was."

But other questions remain: How and why could that have happened? And who should be held accountable?

"There are massive penalties, both civil and potentially criminal, that apply for killing a protected marine mammal," says Brent Planer, executive director of San Francisco's Wild Equity Fund. But, he adds, enforcement of those sanctions depends on the National Marine Fisheries Service, which is now investigating the incident.

Alternately, legal proceedings "could originate with some of the citizen groups that are understandably upset about the death of this whale," says Andrea Treece, a senior attorney with the Center for Biological Diversity.

But such a suit would hinge on evidence that the Pacific Star was in some way negligent or otherwise liable. In their desire to find such evidence, some outraged coastal denizens have focused on the vessel's Geophysical Survey Permit from the California State Lands Commission.

The Pacific Star "was surveying in California waters for a month without a permit" charges Steve Sullivan, vice president of Sea Surveyor Incorporated, a Benicia-based company that also does seafloor mapping. "Their permit expired Sept. 30. And the State Lands Commission did not renew [it] until Oct. 22, which was three days after the whale was impacted."

That's literally true, but not technically correct.

Fugro-Pelagos, the company that hired the Pacific Star for the survey project, applied to renew its permit last July. But "because of state budget cuts or furloughs or something," says Semans, that application "got bumped off the August agenda, the September State Lands Committee meeting was cancelled, and when it was finally approved on the October agenda, it was backdated to Oct. 1. So technically they were covered during the period during which the whale was hit."

The whale's death comes at a time when emotions are already running high around two other overlapping concerns. The National Resources Defense Council and other environmental groups have been fighting the U.S. Navy over its use of high-intensity sonar in antisubmarine training exercises in California coastal waters, arguing that the midfrequency sounds harm whales' and other protected marine mammals' hearing and ability to navigate, mate and find food.

Concurrently, the Marine Life Protection Act has aroused fierce antipathy along the North Coast, with charges of cronyism, indifference to local economic impacts and a lack of public transparency.

The Pacific Star was using sonar to map the topography of the ocean floor, collecting data for use in defining the MLPA zones where fishing and other recreational uses of the ocean waters could be banned.

"None of those biologists follow the legal guidelines for conducting sonar surveys in the ocean," Steve Sullivan charges. "They're out there surveying away without obeying the rules that govern their use."

All sonar is not created equal. The powerful sonic blasts used for naval exercises or identifying the geological strata beneath seafloor are much different than the sonar employed in mapping the surface of the ocean bottom, Semans explains. "That's off the shelf, commercial hardware, at the same frequency range as any depth finder that's on any recreational commercial boat.

"Baleen whales don't hear that sonar," she asserts, "so they wouldn't even hear the boat operating."

Sullivan remains unswayed. "There has never been a survey vessel that has impacted and killed a whale until now," he says. "I don't want to say I told you so, but at the next meeting of the Ocean Protection Committee, that's exactly what I'm going to stand up and say."

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