Great white shark sightings are becoming more frequent in Atlantic Canada
There have been more great white sharks swimming in Atlantic Canadian waters in recent years, and that’s good news.
During the last decades of the 20th century, populations of great white sharks in the region were decimated when caught as bycatch, i.e. accidentally caught while fishing for something else. The shark became a protected species in the mid-1990s.
« The ocean has been thrown out of balance. We’ve destroyed our shark population and overexploited other things, » said Bob Hueter, chief scientist at Ocearch in Sarasota, Florida.
« Now we’re starting to bring things back. »
As top predators, sharks help control populations of mid-level predators such as seals.
Chris Harvey-Clark, a Halifax-based shark researcher, diver and veterinarian at Dalhousie University, has seen the results of conservation efforts.
« White sharks aren’t hard to find at all, » said Harvey-Clark, who has helped film more than 40 underwater documentaries.
In November, he took part in an expedition off the south coast of Nova Scotia, using drones to spot and diving cages to capture images of underwater sharks.
« [We] found it incredibly easy to imagine large numbers of sharks. In a three-day period, we had 15 different sharks, » Harvey-Clark said.
Harvey-Clark will use the photos he took to develop a tool for identifying individual sharks. Individual sharks can be identified by unique markings on their pelvic fins. Scars and other marks can also help with identification.
And Harvey-Clark isn’t the only one spotting sharks off the South Shore. Earlier this month, a lone diver saw one in St. Margaret’s Bay.
« The shark came in from deep water, looked at her, she threw her arms up, and he turned around and got out of there, » he said.
There was another encounter earlier this week, this time involving a charter boat with a dozen divers in the water.
« They had multiple encounters with, probably, the same shark, » Harvey-Clark said.
« The shark passed, looked at them, disappeared out of sight, then 20 or 30 seconds later came back for another look and another look. »
Although there is a need for care, there is little need to worry about sharks, Hueter said.
« You have to think like a shark and you have to remember that the ocean is a wild place, not a swimming pool, » he said.
Sharks aren’t very interested in people, Hueter said, noting there have been very few encounters leading to injuries in Canada. By thinking like a shark, he means avoiding swimming with his favorite prey, such as seals or schools of mackerel or herring.
« Birds diving to the surface and fish coming out to the surface, it’s not a good place to swim, » he said.
There are greater dangers in the sea than sharks, he said, such as rip currents, or even just the trip to the beach.
Search for mating places
Hueter will return to Atlantic Canada next week to continue a five-year project in search of great whites along the Atlantic coast.
The original snowbirds, they spend their summers in Atlantic Canada while wintering off the coast of Florida.
« What we’re collecting is the whole life of these sharks, from birth to death, » Hueter said.
In 2016, Ocearch confirmed a nursery area for great white sharks off Long Island, where they were able to tag hatchlings and track them by satellite as they grew. This provides valuable information about their summer and winter feeding grounds.
“The final piece is where they mate, because as sharks they mate like mammals, they don’t breed like other fish,” Hueter said.
« We think this happens off the Carolina coast in late winter to early spring. »
Ocearch has a free shark tracking app that anyone can use to see the location of tagged sharks. Users can also submit reports of their own sightings.