Are Quebec's rivers getting too loud for belugas?

The Saguenay River may be getting too loud for beluga whales to communicate with each other, causing calves to lose their mothers and putting their lives at risk.

An increasing number ofwhale carcasses that turn up in Quebec belongtopregnant females, mothers and newborn calves.Experts in the areacalled the situation an "epidemic."

Of the 14 carcasses recovered in 2015, six were newborn calvesandthree were pregnant.In 2014, 11 beluga carcasses were recovered, and six of them were babies.In 2013, 17 deadbelugas were found, and four ofthem were babies.

That has prompted a team of researchers affiliated with theGroup for Research and Education on Marine Mammals(GREMM), based inTadoussac,to spend the summer exploring what is behind the spike in whale deaths.

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Between a city street and a jackhammer

The researchersare working from the theory that beluga calves have soft calls, which may be drowned out by the noise from ships, ferries and boats in the Saguenay and St. Lawrencerivers.

Belugasrely on their hearing to "see," so too much noise pollution could hamper efforts of female belugato find their offspring.

"In fact, the noise of boat motors in certain areas of the St. Lawrence is so loud that, if humans were exposed to the same sound levels, they would be required to wear safety equipment,"Peter Scheifele, a professor at theUniversity of Connecticut,observed back in1998.

He compared the noise levels then in certain parts of theSt. Lawrence to somewhere between a city street and a jackhammer.

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Drones andunderwater microphones

The director of the marine research group atGREMM, RobertMichaud, said there has been a recentincrease in traffic aroundCacouna, about 200 kilometresnorth ofQuebec City, which could behaving a negative impact on mothers and their offspring.

GREMMis using drones and underwater microphones to investigate their hypothesis.

"This strategy will help us understand in what context calves use their cries and how those cries can be masked by the passing boats,"Michaudsaid.

Quebec's$9-billionmaritime strategy, which seeksto invest in projects along the St. Lawrence River, worriesMichaud.Hehopes the government will backprotected areas for the belugasalong with any economic development.

The organization is asking the provincial and federal governments to create a protected area in the river that will be free from noise.

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