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Sonar affects
whales’ song,
study shows

The research off Hawaii
found no sign of extreme
behavior in humpbacks

Associated Press

A powerful new sonar being tested by the Navy affects the length of humpback whale songs but doesn't seem to lead to any other extreme behaviors, according to a new study.

Scientists reported today that the low-frequency, high-range sonar used to detect submarines extended the mating songs of some humpbacks while others stopped singing altogether.

"We looked for any sorts of extreme responses like breaching, where the animal would jump out of the water and swim rapidly away from the sonar," said Patrick Miller, the study's lead author and a researcher at the Woods Hole Oceanographic Institution. "We didn't observe any sorts of extreme reactions."

The new sonar has come under greater scrutiny after a biologist hired by the National Marine Fisheries Service suggested a possible link between Navy traditional sonar tests and ear hemorrhages that fatally disoriented the animals.

In March, 16 whales of four different species beached themselves in the Bahamas. Seven died, and initial autopsies suggested the deaths might have been linked to the Navy tests.

The latest research took place off Hawaii in 1998. Miller and his colleagues first recorded the whale songs without the sonar and later asked the Navy to transmit the signals. Of the 16 whales monitored, five stopped singing altogether. The remainder sang on average 29 percent longer when the sonar was activated than without it. The findings appear in today's issue of the journal Nature.

The research, sponsored by the Navy but conducted by independent scientists, said it wasn't clear how much of a threat the sonar and its effects on mating songs pose to whales. But Miller said the Navy should avoid active breeding areas when using the new sonar.