There are about 525 North Atlantic right whales left in the world. At least nine have died off the coast of Atlantic Canada in the past two months.
On Monday, animal advocacy and conservation group Marine Animal Response Society (MARS) said three more decomposed carcasses were discovered.
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MARS director Tonya Wimmer says these deaths are unprecedented.
“We’ve never had this many right whales die off in one season.”
Wimmer explains there are potentially more whales that have died and haven’t been found, and there may be more deaths to come. Here’s a look at the plight of the whales.
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What are North Atlantic right whales?
The North Atlantic right whales — with a lifespan of about 75 years — are one of the most endangered large whales in the world, according to the Department of Fisheries and Oceans Canada. They’re mostly found on the Atlantic coast of Canada and the U.S.
The massive mammals can reach up to 18 metres in length and can weigh 96,000 kilograms, according to the World Wildlife Fund (WWF).
Whales are travelling to the Gulf of St. Lawrence
The whales had been living in Bay of Fundy and Roseway Basin waters until about five years ago, but Wimmers says they recently began appearing in the Gulf of St. Lawrence.
She explains that this is likely because Bay of Fundy “food isn’t great,” but the exact cause — and whether it’s related to climate change — is still being researched.
“How a warming ocean will impact them is quite unknown at the moment,” Wimmers says.
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The change in location is significant because conservation efforts, such as rerouting shipping lanes, were carried out mainly in the Bay of Fundy.
Whales likely died due to ‘human activity’
The whales, the first death of which was discovered on June 7, were likely killed because of “human activity,” Wimmers said. While it’s unclear exactly what it was at this point, ship accidents, fishing gear and pollution can all be harmful to the mammals.
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She added that preliminary autopsies done on the animals found that three died of blunt trauma and one of chronic entanglement.
The cause of death is unknown for other whales, and it can often be difficult to discern since whales decompose quickly, Wimmers noted.
What can be done to prevent the deaths?
“The main thing that has to happen now is a real, collaborative effort,” Wimmers says, adding that the government, conservation groups and scientists all have to work together to address the issue.
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She adds that the massive mammals are not reproducing quickly, only five calves have been born this year, which increases the pressure to save the existing whales.
Biologists are currently working to figure out how more deaths can be prevented.
The fisheries department dispatched aircraft and Canadian Coast Guard vessels to locate, tag and get biological samples from the dead whales in June.
— With a file from the Canadian Press
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