LOS ANGELES, July 15 (UPI) — Whales react to a noisy environment in the same way humans do — by raising their voices to be heard, U.S. researchers say.
Researchers monitoring 14 right whales — seven males and seven females — in Canada’s Bay of Fundy found the animals increased their call amplitude in proportion to increases in background noise levels, the Los Angeles Times reported Sunday.
“Whales are compensating for increased ocean noise by going up in volume when they call to one another,” said Joseph Gaydos, chief scientist for the SeaDoc Society at UC Davis, “which is basically the same thing that humans do when they’re trying to talk in really noisy bars.”
The North Atlantic right whale is listed as an endangered species, and its primary habitat is the coastal waters of the eastern United States and Canada, an area with high levels of commercial, naval and recreational shipping traffic, said Susan Parks, lead author of the study and assistant professor of acoustics at Pennsylvania State University.
Noise generated from the commercial ships has the same pitch as a right whale’s call, Parks said. “This is a problem because its noise source overlaps the frequency range of the whales’ calls,” she said.
Sound is vital to the right whales’ survival because they depend on it for vital activities including communication, navigation and feeding, and researchers are concerned about the threat of increased noise pollution in the oceans.
“Marine mammals are experiencing greater amounts of noise increases than many terrestrial animals, so it’s important to understand how they respond to this and what the effects will be,” said Stephanie Watwood, a visiting biologist at Woods Hole Oceanographic Institution.
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