< Previous page

In other comments, Douglas Nowacek, an oceanographer at Florida State University, said it was better to have sonar exercises at one location than at unknown and unmonitored locations. He said the North Carolina site was a better choice than Florida.

But he said the Navy's conclusion -- that endangered right whales do not frequent the waters of the proposed range off North Carolina -- is unfounded.

Nowacek said the most worrisome conclusion in the study is the Navy's statement that whales could tolerate sounds up to 190 decibels before altering their behavior significantly.

"I believe 190 decibels ... is completely unprecedented and, more importantly, not supported by available data," Nowacek said. He said that he and other researchers had seen strong responses from whales at sound levels far below that.

Eye on Hawaii

Scientists suspect that sonar harms whales, but they do not know exactly why.

Additional evidence was revealed Thursday, when the federal Fisheries Service linked military sonar to an unusual stranding of more than 150 whales in a shallow Hawaiian bay two years ago.

The melon-headed whales, which require deep waters to feed, were discovered early July 3, 2004, in Hanalei Bay on the island of Kaua'i. U.S. and Japanese navy ships participating in the Rim of the Pacific Exercises had used sonar on and off for nine hours the day before.

A flotilla of more than 20 kayaks managed to herd the whales to safer waters July 4. Only one, a young calf, remained. It died.

Navy officials said Thursday that they were reviewing the fisheries report. But the Navy's position is that "it's extremely unlikely" sonar caused the Hawaii stranding, said Lt. William Marks, a spokesman based at the Pentagon.

For one, the stranding began about six hours after the Navy ships stopped using sonar, he said. It's not clear whether the animals, if close to the ships, could have reached the bay en masse by then.

Fisheries officials stressed Thursday that they could not prove sonar caused the trouble. But they found no other obvious explanation -- not dangerous weather, harmful algal blooms, illness or evidence of nearby predators.

"We're not convinced that sonar was the unequivocal or sole cause of the event. It's plausible, if not likely, it was a contributing factor," said Dr. Brandon Southall, director of the fisheries service's acoustics program.

This same agency last month announced that it was unable to determine whether sonar played a role in the stranding of more than 35 whales on North Carolina's Outer Banks in January 2005. U.S. Navy ships had used sonar days before.

It's not certain how the Hawaii findings will influence the National Oceanic and Atmospheric Administration's regulation of sonar use on the range the Navy wants to build off North Carolina.

Underwater geography and marine life differ in this state.

< Previous page