Using sound to save whales from extinction

By Russ Bynum

updated 9:54 p.m. ET Feb. 11, 2007

SAVANNAH, Ga. - Beneath the ocean, microphones listen around the clock for the mooing calls of endangered North Atlantic right whales in an eavesdropping experiment that could help save them from extinction.

For 20 years, researchers have relied on airplanes and their own eyes to keep tabs on right whales that migrate south to the coasts of Georgia and Florida every winter to birth their calves before returning to the North Atlantic.

Cornell University scientist Christopher Clark thinks he's got a more efficient method that can be used to warn boaters and commercial ships to steer clear of the rare whales — use sound to pinpoint their whereabouts.

'24-7 listening system'
"You've got a 24-7 listening system," said Clark, director of bioacoustics research at the Cornell Laboratory of Orinthology. "I think it has all the promise of offering mariners real-time information about whether or not there are whales in the area."

Collisions with ships killed four of six right whales known to have died in the Atlantic Ocean last year. Scientists believe only about 350 of the whales still exist, so losing even one is a step toward extinction.

In late February, rearchers will collect six buoys they sunk in mid-December off the coast of Brunswick, 75 miles south of Savannah. Each contains a digital recorder collecting more than 1,400 hours of undersea sounds.

Those recordings will help determine if whales make enough noise — which sounds like a "moo" or a "whoop" — off the coast to justify trying a more sophisticated surveillance system that automatically picks out whale voices and relays them by satellite.

Gary Waxman, a developer building luxury homes and condominiums on the Brunswick waterfront, donated the $125,000 used to fund the project.

Clark says the advantage of audio surveillance is that it works day and night and in all weather. Spotting right whales from the air requires daylight and clear skies for flying

Though the whales measure up to 56 feet long, spotters have only three planes to look for them over more than 4,000 square miles of ocean between Sapelo Island, Ga., and St. Augustine, Fla.

'Needle in a haystack'
"It is like finding a needle in a haystack," said Amy Knowlton, a right whale researcher at the New England Aquarium in Boston. "You might see a dozen whales in a day, and the next day you might see nothing."

Clay George, right whale program coordinator for the Georgia Department of Natural Resources, said whales sighted in daily flyovers get reported to the Navy, which alerts ships coming into port.

But aerial surveilance is expensive — costing up to $500,000 per winter — and gets limited results. George estimates the planes spot only about 25 percent of the right whales present off the southeastern coast.

Waxman got involved after learning of the right whales' plight while working with Georgia regulators on permits for his coastal housing development and a marina that would launch pleasure boats in the same waters as the whales.

Waxman brainstormed with his environmental consultant and they got the idea of contacting Clark at Cornell University.

Clark has been eavesdropping on right whales in Massachusetts' Cape Cod Bay since 2001. Using federal grant money, he's also recorded whales off Savannah and Charleston, S.C., since 2004.

Because sound travels farther underwater than it does in open air, Clark said, his microphones can pick up whales up to 10 miles away.

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