ASSOCIATED PRESS
Greg Schorr, a researcher at Cascadia Research Collective, photographs a pod of pilot whales off the Kona coast. The crew had been looking for beaked whales for a study of their vulnerability to U.S. Navy sonar.
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Team scours seas for whales
Associated Press
KAILUA-KONA » Robin Baird's research team gazes for hours into the horizon, searching for rarely seen beaked whales.
The small, gray animal has been at the center of the dispute over the Navy's use of sonar ever since several washed ashore bleeding around their brains and ears during Navy exercises in the Bahamas seven years ago, along with a few similar incidents.
"They appear to be the most susceptible group of cetaceans to impacts from Navy sonars," said Baird, an Olympia, Wash.-based marine biologist whose team recently spent three weeks off the Big Island studying whales.
The studies come at a critical time for the Navy and the whales.
Training sailors to use sonar has become one of the Navy's top priorities as more nations, including China, have acquired quiet, hard-to-detect diesel submarines. In many cases, the only way the U.S. Navy can find these stealthy ships is by pumping sound through the water with mid-frequency active sonar and listening for an echo.
Galvanized by the strandings, environmentalists are filing lawsuits challenging the Navy's plans to exercise with sonar because they claim the drills will harm whales.
Beaked whales rarely show themselves before humans and are among the least understood marine mammals.
To learn more, Baird's research team ventured off the Kona coast of the Big Island to attach time-depth recorders and satellite tags to beaked whales to monitor the animals' diving patterns and movements around the islands.
The researchers also took photos of each whale and dolphin they saw to add to a catalog tracking the various cetacean species inhabiting the islands.
Many scientists suspect beaked whales' ability to swim at great depths for long periods makes the species more vulnerable to the effects of sonar.
One theory says the sonar's loud noise startles the whales, prompting them to surface unusually rapidly. This gives them gas bubble lesions in organs including the liver, a phenomenon similar to the bends in humans. Still, this hypothesis hasn't been verified.
In the Bahamas, scientists this month were running controlled experiments testing how beaked whales and other marine mammals respond to different sounds. Eventually, the scientists will observe how the whales react to mid-frequency active sonar.
The Navy doesn't want to deny its sailors the full spectrum of sonar training because of unproved theories. Environmentalists argue there's enough evidence to require the Navy act on the safe side and take more aggressive measures to protect whales.
Adm. Robert F. Willard, U.S. Pacific Fleet commander, said the Navy is willing to post lookouts on its ships to monitor for whales and limit sonar use when whales get too close.
But he said there's no scientific basis for more stringent measures demanded by some environmentalists, including designating entire areas as non-sonar zones.