- The Washington Times - Monday, September 24, 2007

KAILUA-KONA, Hawaii (AP) — Robin Baird’s research team stares at the horizon for hours, searching for rarely seen beaked whales.

The small, gray marine mammals have been at the center of the dispute over the Navy’s use of high-intensity sonar ever since several washed ashore with bleeding around their brains and ears during naval exercises in the Bahamas seven years ago.

“They appear to be the most susceptible group of cetaceans to impacts from Navy sonars,” said Mr. Baird, a marine biologist based in Olympia, Wash., whose team recently spent three weeks off Hawaii’s Big Island studying whales.

Training sailors to use sonar is a top priority for the Navy as more nations, including China, have acquired quiet, hard-to-detect submarines. In many cases, the only way the Navy can find these stealthy ships is by using midfrequency active sonar, firing bursts of sound through the water and listening for an echo off a ship’s hull.

Environmentalists have filed lawsuits challenging the Navy’s plans for sonar training exercises, claiming the underwater noise harms whales and arguing that there is enough evidence to require the Navy to take more aggressive measures to protect the animals.

The Navy says it doesn’t want to deny its sailors the full spectrum of sonar training because of unproven theories.

Beaked whales are among the least understood marine mammals. To learn more, Mr. Baird’s research team headed off the Kona coast of the Big Island to attach time-depth recorders and satellite tags to beaked whales in order to monitor the animals’ diving patterns and movements around the islands.

Beaked whale adults stretch an average 18 feet — about half the length of a typical humpback whale, the most famous and easily spotted whale around the Hawaiian Islands.

As they hunt squid, they dive deeper than almost any other marine mammal. One that Mr. Baird tagged in previous years descended more than 4,900 feet.

Many scientists suspect it is the beaked whales’ unique ability to swim at great depths for long periods that makes them more vulnerable to sonar.

One theory, not verified, is that the loud sonar noise startles the whales, prompting them to surface unusually rapidly and causing injuries similar to the bends in human divers.

“The question is: Why would it have a different response from other species? Or why would a behavioral response affect them more?” Mr. Baird said.

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