Underwater noise pollution also disturbs fish, study suggests

Plastics and oil aren't the only types of pollution having a negative impact on fish.

According to a new study entitled Sound the Alarm, noise is also a growing problem for the aquatic animals.

"In terms of fish behaviour and physiology, it's negative responses across the board," said Kieran Cox, a doctoral student at the University of Victoria.

Cox and fish ecologist, Francis Juanes, led the collaborative team that conducted the research, which was published in the peer-reviewed journal Global Change Biology. 

They reviewed 42 studies involving human-caused underwater noise and its impact on fish.

Researchers have already studied the more well-known impact of underwater noise pollution on larger creatures like killer whales, but the research team says fish also pay a price for living in increasingly noisy waters.

Approximately 700 fish species use sound to communicate. The researchers found that even the noise from a small boat motor can be disruptive.

"Their foraging behaviour, their perception of predation, all of these kinds of things are affected," said Cox. 

And, just with like humans, unexpected noises can be frightening for fish.

"Stress in fish is going up, across species and across experimental conditions," he said.

Cox believes underwater noise pollution is a problem that needs more attention. The study found that noise in the ocean has been increasing steadily in the past few decades. 

More studies are underway, including research on the impact of noise on British Columbia's salmon populations.

With files from Greg Rasmussen