Necropsy important to understand if human activity caused mammal’s death

Researchers perform a necropsy on a juvenile blue whale that washed ashore in East Berlin, N.S. (Marine Animal Response Society)

A team of scientists will use excavators and knives to try to learn what killed a whale that washed up on a beach in East Berlin, N.S., earlier this month.

The juvenile blue whale floated ashore in the small South Shore community on May 2.

The 18-metre animal has been dead for at least two months. It is the same whale that was spotted dead in mid-March off Port aux Basques, N.L., something scientists were able to confirm by comparing grooves in its throat.

Tonya Wimmer, the director of the Marine Animal Response Society, said it’s important to understand whether the whale died because of human activity. Blue whales are listed as an endangered species in Canada.

“It’s only been because people have looked at animals that have died that we’ve really even started to identify how often they’re threatened by different things — whether it’s shipping, whether it’s fishing, pollutants, whatever,” Wimmer said.

“Without doing investigations like this, we don’t really have that true sense of how much of these animals are impacted by us.”

‘Horrific sight’ — and smell

The juvenile female blue whale is about 18 metres long. (Marine Animal Response Society)

Wimmer said the dead whale is “a pretty horrific sight.”

“Seeing them alive is one of the most magnificent things I think people can ever experience and hear,” she said. “They’re absolutely magnificent animals, so to see one lying on a beach that’s dead … it’s not the way you want to see them.”

The smell isn’t so great, either.

“It’s foul,” Wimmer said. “It’s definitely not pleasant. I don’t know if there’s anything comparable that most people would have smelled.”

She pauses. Maybe there’s one comparable thing.

“Extreme horrible compost bins that … people have had meat in.”

Researchers will examine organs

An excavator was brought to a beach in East Berlin, N.S., to help with the necropsy of the blue whale. (Marine Animal Response Society)

Representatives of the Canadian Wildlife Health Co-operative, the Atlantic Veterinary College at the University of Prince Edward Island, the Marine Animal Response Society, Dalhousie University, the New Brunswick Museum and the Department of Fisheries and Oceans will be on site during the necropsy.

First, scientists will slice the whale open from its head to its fluke.

Then, simply because the animal is so heavy — Wimmer estimates it weighs 50 to 60 tonnes — they’ll use a backhoe to peel back the thick layers of blubber and muscle.

Scientists are performing a necropsy on this juvenile blue whale to understand why it died. (Jerri Southcott/CBC)

If the organs are still identifiable, the researchers will open those and take tissue samples to analyze in the lab to look for signs of disease. They’ll also open the esophagus and stomach and examine the contents to check for plastics or other materials.

“Their organs are huge,” Wimmer said. “When you actually look at them … on the inside, it’s amazing.”

Wimmer remembers taking part in a necropsy of a sperm whale on P.E.I. that was about 20 metres long.

“I remember when we opened it up, and looked at the — I think it was the heart — and I realized it was almost the size of my car.”

Mind you, Wimmer drives a Volkswagen Rabbit. “Not a massive car,” she admits.

Unlikely to explode

Everyone involved in the necropsy will be wearing protective gear such as goggles and gloves to protect them from diseases that can be transferred from the whale’s tissue.

But Wimmer said it’s unlikely that the whale will explode, as seen in a popular online video of a dead whale in the Faroe Islands. Since the weather has been relatively mild, and since the whale has been floating in the cold North Atlantic for two months — “a sort of natural freezer” — the pressure inside has not built up to dangerous levels.

This dead juvenile whale floated from Port aux Basques, N.L., to East Berlin, N.S., over the course of about two months. (Marine Animal Response Society)

“We don’t anticipate that with this one — not to that extent,” Wimmer said. “If you put a knife in it, it’s not going to blow up.”

She said human safety is the No. 1 priority, and the team has specific protocols to follow about how they puncture the carcass and let the air dissipate.

Wimmer said despite having participated in about a dozen necropsies on large marine mammals, she never gets tired of seeing the animals up close.

“You never get to see a whole whale,” she said. “You literally get to see them when they surface, they take a breath of air and then they’re gone. So it’s a very intriguing situation for people to see a whole animal and it really gives you a sense of the scale.

“It doesn’t always smell good, but it’s fascinating.”