This great white shark hangs out off St. John’s – .

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This great white shark hangs out off St. John’s – .


Researchers caught and tagged Helena, a four-meter-long tall white, in 2019. She has since found her way to the coast of Newfoundland. (Submitted by Ocearch)

A great white shark named Helena, which scientists hope can help unravel one of the dominant mysteries of its species, has returned to the freezing waters of Newfoundland from its winter home in the Gulf of Mexico, according to a group of scientists.

A team of marine biologists from Ocearch, an organization that collects data on sharks, captured and tagged Helena for the first time in 2019.

Helena was only four meters tall at the time, remembers Chief Scientist Bob Hueter.

“She’s had one hell of a hike since we tagged her,” Hueter said, adding that the shark had traveled over 20,000 kilometers around the Atlantic Ocean.

“This is her second trip to the Grand Banks area… She seems to be really enjoying this summer there.

The region off the south coast of Newfoundland, he explained, provides abundant feeding grounds for great whites, who endure freezing temperatures to take advantage of large fish stocks. The team observed gravid sharks in the area taking advantage of the summer months to build muscle and prepare for calving.

Hueter suspects that Helena is not yet old enough to mate, but may be feeding voraciously to prepare for giving birth to young next spring, likely off the coast of the northeastern United States.

The captured sharks are held on a platform for up to 20 minutes to be tested while a pump draws seawater past their gills. (Submitted by Ocearch)

Watching his movements on Ocearch’s public tracking platform, he says, will give his team clues to a mystery not yet solved by researchers.

“The one piece that has really escaped biologists is where exactly do they mate,” Hueter said. Ocearch’s group of tagged sharks, which regularly return their locations to the team, have yet to reveal how members of the species go about getting pregnant – but sustained population numbers tell the team that they actually do it somewhere.

On Friday, Helena appeared to be swimming just east of St. John’s.

“It’s about as far north as they like it,” Hueter said. Later in the season, it could return to the Gulf of Mexico or winter off the Carolinas, before joining other sharks in Canadian waters next year.

The areas off Nova Scotia are especially teeming with animals, Hueter adds. His team has embarked on several expeditions to Atlantic Canada, transporting sharks on a specialized hydraulic platform for up to 20 minutes at a time to take measurements and samples, before affixing and tagging them. to release.

Helena is one of 416 sharks tracked by the Ocearch team. (Submitted by Ocearch)

They have tagged 416 sharks since 2007, collecting data that could lead to research into new antibiotics – based on sharks’ natural ability to heal wounds quickly – and help scientists understand the contaminant loads from pollution. oceans.

Although the team works globally, their Canadian expeditions result in surprisingly successful catches, despite the freezing waters to the north.

“Part of it is so fun working up there because nobody knew it,” Hueter said. “Knowledge of white sharks in Atlantic Canada was that they were basically not very common, that they were possibly endangered.

“I think we’ve drawn the curtain on this. “

Read more about CBC Newfoundland and Labrador

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