What's killing right whales? P.E.I. wildlife pathologists spend summer searching for answers

A team of scientists and volunteers from the Atlantic Veterinary College racedagainst time as they dove into action in late June, knives in hand.

They needed to work as quickly as possible on the necropsies of dead North Atlantic right whales before the giant endangered animals decomposed further. At one point, they performed three necropsies in three days.

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Among thesescientists was Dr. Laura Bourque, wildlife pathologist and 2013 graduate of the AVC. She had just been hiredatthe college when the call came in about the right whales.

"It's daunting, to be honest.I hadn't done anything as large as a right whale before here," she said.

"I'd done dolphins, and belugas and things like that, they're big, but they're manageable because you can do them in the lab.This is an entirely different situation because this animal they're huge and you have to do them out in the open."

Time was of the essence,as more dead right whales turned up throughout the summer. Atleast 14 have been found dead off the east coast of Canada and the U.S. this year.

We got a whale done a day. That's pretty good.-LauraBourque

The first challenge was getting to the whale carcasses, which were floatingaroundthe Gulf of St. Lawrence.

Initially, they tried to assess the whales at sea.

"We thought we might be able to do some kind of superficialpost-mortemwhile they were floating in the ocean, and we did try that," saidBourque.

"There's a fairly famous picture of Pierre riding a whale in the middle of the Atlantic, but we were only able to do very superficial work."

Dr. Pierre-Yves Daoustis a well-known wildlife pathologist in P.E.I., one of the leads for the Canadian Wildlife Health Cooperative.

He was instantly on board when Fisheries and Oceans made the decision to tow three of the sixcarcasses to P.E.I.'s far western tip, in a location called Norway.

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"We were well-positioned to respond very quickly, because of the size of the animal, it is a very big challenge," saidDaoust.

Butfirst,he needed a team of volunteers to get the work done quickly.

"Fortunately, because we are at a veterinary college, the vast majority of our students have the knowledge of how to handle a knife," saidDaoust.

"So they are ideal volunteers to help us in this task."

Daoust,Bourqueand the others worked10to 12hours a day to get it done.

In each of the three days at Norway,they were able to doone complete necropsy, from head to tail.

"You have to have heavy equipment to help you move the tissues and things around, it is daunting," Bourquesaid.

"On a rocky beach, which is not always easy to manoeuvre.We got a whale done a day," she said."That's pretty good."

Bourquesaid the whales decompose quicklyandwere pretty far gone by the time they were towed to shore.

"If we want to get a good report, and really figure out what's going on with these, we need to get the tissue as fresh as we can, because that will affect all of the different diagnostic processes," she said.

Some of the whales were very "flat," as the scientists call them.

"A right whale has a very thick layer of blubberand as it decomposes, it gets a little bit bloated, so those are very round whales," Bourqueexplained.

"But a lot of them were flat, they've gone past that and have lost all of their internal organs, and there's not much to work with."

Since the necropsies, Daoust and Bourque have been putting in long hours in the lab, analyzingtheir findingsand working on a final report.

But even as recently as Tuesday, they were back in the field performing another necropsy on Miscou Island, N.B., on yet another right whalewithwhat appeared to be fishing gear entangled around its carcass.

There are some working theories, after preliminary necropsy results revealed some of the dead whales suffered blunt trauma and showedsigns of chronic entanglement, likely from fishing gear.

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But Bourque said experts still can't say definitively what killed any of the whales.

"We know entanglement is an issue right now, and we're wondering about boat strikes. But it's going to be a while before we can say anything definitive," she said.

"In our report we can say 'yes or no there was evidence of trauma.' But then we need to pair that with, were there even ships in the area at that time?"

'It's a terrible situation'

Bourque said she and Daoust, along with pathologists from the University of Montreal, who led two of the necropsies in Quebec, are still waiting on the results from diagnostic testing of tissue samples from the whales.

For the two wildlife pathologists, the desire to help protect the right whale is driving them in their quest for answers.

Daoust calls the deaths "unprecedented."

"It's a terrible situation for that population when every single animal that dies is critical to the population," he said.

How an unprecedented number of deaths put the endangered North Atlantic right whale's future in peril

7 years ago

Duration 2:56

Here's how the species came to be in such deep trouble.

For Bourque, at the start of her career, the summer has been a learning experience, but also one with high stakes.

"It certainly does increase the pressure mostly because these are extremely endangered animals and I know myself and Pierre and everyone else that I've worked with, we're so worried about the state of their population," said Bourque.

"I hope we get to the bottom of this, we are doing our absolute best to do that."