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Climate trackers
find increase
in humpbacks

But the researchers say it's
too early to take them
off the endangered list

By Harold Morse
Star-Bulletin

A study tracking long-term changes in climate associated with global warming has yielded a related finding: The humpback whale population may be making a comeback.

More whales were spotted in aerial searches than were expected, said Joe Mobley of the University of Hawaii.

"If the trend is reliable, it means the animals are increasing at the rate of 7 percent a year," he said.

But he and others present at a meeting last night at the East-West Center on underwater sound waves were reluctant to speculate about when humpbacks might increase enough to come off the endangered species list.

The North Pacific Acoustic Laboratory is formerly known as the Acoustic Thermometry of Ocean Climate and measures the temperature of Pacific waters by using sound waves.

"Sound travels a little bit faster in warmer water than in cold water," said Peter Worcester of Scripps Institution of Oceanography and the University of California-San Diego.

He told some 20 people at the Hawaii Imin International Conference Center last night that sound is a much faster way to check ocean temperature, since it can travel 3,000 kilometers (1,860 miles) in 40 minutes.

Part of the research was concerned with the effect on marine life.

Worcester's colleague, Mobley, worked out of Kauai on the marine mammal impact.

"The main focus was, of course, humpback whales," Mobley said.

The relatively minor level of sound waves had little noticeable effect on whales, Mobley said. It takes sophisticated computer technology to bring the sound level up to track it over long ocean reaches, Worcester said.

Passing ships affected whales more than the experimental sound waves, Mobley said.

Last night's public meeting was to provide information and allow public comment on a draft environmental impact statement for the North Pacific Acoustic Laboratory project, which proposes to reuse the power cable and sound source north of Kauai for another five years.

That sound source and another near California transmitted for about two years, Worcester said.

Ocean temperature change can have huge effects on climate, he said.