Humpback whales stop singing when ships are near

Humpback whales are famous for their eerie, underwater songs. But researchers in Japan said Wednesday these massive marine creatures stop singing, at least temporarily, when human-driven ships are nearby. Researchers focused on the remote Ogasawara Islands in Japan, some 1,000 kilometers south of Tokyo, where a single passenger-cargo liner passed through the area once per day.

“The main reaction of humpback whales was to stop singing either when the ship approached or after it passed by,” said the study in the journal PLOS ONE, led by Koki Tsujii from Ogasawara Whale Watching Association and Hokkaido University. Fewer male humpbacks sang in the area within 500 yards (meters) of the shipping lane than elsewhere. 

“After the ship passed by, whales within around 1,200 meters tended to temporarily reduce singing or stop singing altogether,” said the study. Many whales did not start to sing again until a half hour after the ship was gone from the area. Since ocean noise has been on the rise in recent decades, some experts said the findings raise new questions about what other whale behaviors might be changing due to mounting human presence on the high seas.