Killer Whales Strain to "Talk" Over Ship Noise?

A baby killer whale surfaces near adults in Puget Sound. The calf was born in March 2009 to a pod that lives near the San Juan Islands off the coast of Washington State.
The San Juan killer whales "talk" more during foraging than traveling, researchers said in September 2009. But since the whales also have to raise their voices to be heard above boat noise, scientists worry that the animals may be using up too much energy during hunts, even as their preferred prey, chinook salmon, are on the decline. Photograph courtesy Center for Whale Research via AP

From National Geographic:

Killer whales raise their voices to be heard over boat noise, and the effort may be wearing the whales out as they try to find food amid dwindling numbers of salmon, new research says.

The killer whales of Puget Sound make more calls and clicks while foraging than while traveling, suggesting that such mealtime conservations are key to coordinating hunts, the work reveals.

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