Shark tales: Canada’s great whites

As white sharks make their presence known off the coast of Atlantic Canada, researchers and locals want to know: should people be worried? 

A white shark swims among the plankton.
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On a crisp October morning off Nova Scotia’s Frying Pan Island, about an hour-and-a-half southwest of Halifax, a shot echoed across the waves as a camouflaged hunter brought down his second sea duck of the day. On command, Pepper, his two-year-old Chesapeake Bay retriever, leapt off the boat to retrieve the bird, which had landed a stone’s throw away in about six metres of calm ocean. Taking the duck in her mouth, Pepper turned back with her quarry. Then the water exploded.

A white shark swims among a school of butterfish.
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A large shark erupted from beneath the dog, launching Pepper’s body into the air. Then, just as suddenly, it dragged her beneath the waves. Her owner watched, aghast, as she surfaced and struggled back to the boat. He pulled Pepper back aboard, but she was bleeding heavily and died from her wounds within minutes. It was, shark biologists and taggers agreed later, almost certainly a juvenile great white shark that killed Pepper. 

White sharks have lived beneath the steely waves off Nova Scotia since long before humans. Around six million years ago, the wide-ranging, solitary apex predator likely evolved from mako sharks in the Pacific Ocean before making its way into the Atlantic. Of all nature’s creations, few rival sharks in the human emotions they provoke: fear, hatred and obsession, but also desire and fascination. “In a deeply tribal way,” wrote sociobiologist E.O. Wilson, “we love our monsters.” And although these iconic, toothy predators have a fearsome reputation, humans and white sharks coexisted long before the first European settlers arrived in eastern Canada. 

Over the past decade, however, sightings and encounters of white sharks off Nova Scotia have been on the rise, something marine biologists attribute to three factors: warming waters, successful environmental protections and booming populations of grey seals, a primary shark food source. At the same time, so little is known about the predators — including their breeding, migration and feeding patterns — that scientists are increasingly trying to find and tag them, desperate for every data point they can get. Along with a surge in tourism operators and documentary crews trying to find, photograph, film and otherwise profit off the great white shark’s mystique, many locals along these shorelines say they worry about the potentially deadly unintended consequences of efforts to find and interact with the species. Herein lies the rub: to understand sharks, we must first lure them closer, but to lure them closer is to invite danger onto our doorstep. 

A tuna head bait suspended from a bait line attracts this white shark.
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About a half-hour drive southwest from where Pepper was killed, three weeks earlier, skipper Art Gaetan and marine biologist Neil Hammerschlag had welcomed a boatload of tourists aboard Atlantic Shark Expeditions’ leased catamaran in Port Mouton. The seas were wild that day, so wild that Gaetan deemed it unsafe to drop the boat’s welded steel shark-diving cage into the strong ocean swells as part of the tour. Since April 2023, when the company started operating white shark tours out of nearby Liverpool, N.S., Hammerschlag and Gaetan have welcomed dozens of guests who, on calmer days, don wetsuits and snorkels in hopes of safely seeing a white shark in the flesh. That day, despite the rotten weather, the pair were determined that their show — a full-day expedition intended to find, glimpse and capture identifying videos of great white sharks using underwater cameras — would go on.

Map: Chris Brackley/Can Geo; Data: Skomal GBB, Braun CD, Chisolm JH, Thorrold SR (2017) Movements of the white shark in the North Atlantic Ocean. Mar Ecol Prog Ser 580:1-16.; Bowbly, H.D., Joyce, W.N., Winton, M.V. Et al. Conservation Implications of White Sharks Behaviour at the Northern Extent of their Range in the Northwest Atlantic. Canadian Journal of Fisheries and Aquatic Sciences. 79(11): 1843-1859 (2022).
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Hammerschlag fell in love with sharks in the early 2000s, an era when shark populations were plummeting worldwide. By then, many species in Atlantic Canadian waters had declined by more than 70 per cent since the 1960s. The most-cited reasons for the drop, says University of Guelph shark researcher and biologist Steve Crawford, include recreational anglers catching and killing sharks for “jaws and records” (a practice that was ended in Nova Scotia just last year), entanglements with commercial fishing gear, and poisoning from toxin loads from consuming prey species lower down the food chain. Today, an estimated 80 million sharks are killed by humans every year; in 2023, 18 human deaths were attributed to shark encounters globally, which was an unusual spike. 

While earning a master’s degree in predator-prey interactions, Hammerschlag partnered with a South African ecotourism operation that offered shark diving tours, which inspired the idea to start a similar business in Nova Scotia. “I knew I was going to cause a whole lot of commotion,” says Hammerschlag, who researched sharks and taught at the University of Miami for 13 years before moving back to Canada. He sees his current business as a win-win: tourists get a chance to see a white shark, while he uses each trip to identify individual animals and record their movements and behaviours. He also carries a shark-tagging stick on board, although he didn’t use it during Atlantic Shark Expeditions’ first season on the water. His accumulated data, he says, will form the basis for future research papers he plans on writing. 

Similarly, the tour company’s skipper, Gaetan, has been obsessed with sharks for as long as he can remember. He saw his first, a dogfish shark, in Cape Breton, N.S., in 1963, during an era when the prevailing view was that the only good shark was a dead shark. His father, a fisherman, had brought five-year-old Gaetan along to check the family’s mackerel nets when he discovered they had been sunk by an influx of dogfish sharks. Grabbing one by the tail, his father slammed it off the boat’s side and tossed it onto the back deck. “I was sitting there with the shark, and I was fascinated,” recalled Gaetan. Suddenly the shark — a female — started to give birth. “All these little baby dogfish were coming out of the shark with their yolk sacs still attached,” says Gaetan. From that moment, he was hooked. 

A tuna head suspended on a bait line floats underneath the surface with eelgrass, plankton and butterfish also visible in the frame.
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A great white shark grabs for a tuna head attached to a bait line.
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In 1996, after retiring early from his job as a navy sonar operator, he started offering blue shark tag-and-release charters. On those trips, Gaetan would take tourists out in his boat, catch sharks, mark them with plastic tags attached to metal anchors and then release them. (When tagged sharks are re-caught and reported, their movements and age add to the body of knowledge about their abundance; thanks to taggers like Gaetan, more than 1,400 blue sharks have been tagged since 2006.) A few years ago, Gaetan sold that business to an employee, moved with his wife to Liverpool, N.S., and was looking for a new project when he met Hammerschlag. 

To understand sharks we must first lure them closer, but to lure them closer is to invite danger onto our doorstep.

Last June, two months after Atlantic Shark Expeditions announced its plans to offer public tours, Gaetan and Hammerschlag rendezvoused inside a community hall in Eagle Head, N.S., to address the anger and uncertainty their business had sparked within the local surfing and marine recreational community. “We had nothing to hide, but people still showed up with tar and feathers,” says Hammerschlag. “They were being fed bullshit.” 

Close-up shots of great white sharks like the one pictured here help researchers to identify individuals by taking note of their scar patterns.
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For weeks, rumours about the business had ricocheted across the tight-knit surfing scene, including that they were chumming (throwing bloody fish parts into the water) to attract sharks. The pair insisted they weren’t doing that, as it’s not allowed under their government permit, although they conceded they do hang large, stinky bluefin tuna heads, sourced from local fishermen, alongside their boat to create an oil slick to accomplish something similar on a smaller scale. Because white sharks are wary and often avoid boats, they said, to do so was simply scientific best practices.

The day I joined them at sea last October, Gaetan taught the catamaran’s gaggle of excited tourists how to hand-line for silvery mackerel, which they then threw into the water to attract a school of leaping bluefin tuna. They weren’t chumming, but like many things at sea, the line between what’s allowed and the potential unintended consequences of human-animal contact can be a thin and often blurry one.

Jessica Bradford is a marine conservationist, surfer and co-founder of the group Queens Ocean Community, which organized the public meeting. One of their issues with Atlantic Shark Expeditions, she says, is that the first time most local residents heard about the shark tours was through the business’s splashy April 2023 media launch. In the absence of information, it made sense, she says, that people were worried. It added insult to injury that the company emblazoned the phrase “Respect the Locals” — referring to the sharks — on T-shirts sold out of a local inn that partnered with the company. “Every couple of years, there’s a new activity popping up related to people wanting to study white sharks, but where’s the policy around these other considerations, like public safety?” says Bradford. She says water users, including surfers but also kayakers, free divers and even hunters like Pepper’s owner, are accustomed to weighing risk out on the open ocean. “The sharks are just another risk-versus-reward we need to think about when doing what we love.”

Art Gaetan, ASE’s captain and co-operator, retrieves bait lines, assisted by marine biologist and deckhand Maggie McKenna.
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Carcharodon carcharia, named by Linnaeus in 1758 — karcharos for “sharpen” and odous for “tooth” — the white shark’s life cycle has remained maddeningly uncertain to scientists, despite millions of dollars and thousands of hours spent trying to track, tag and observe the species over generations. White sharks are cautious, fast and highly dispersed, which means scientific studies illuminating their life cycle and biology have historically been few and far between. For instance, white shark mating rituals have been witnessed only twice in recorded history, both times in shallow waters off New Zealand. And before the discovery of a single tooth linking the species’ genetic lineage to mako sharks in 2012, most scientists believed white sharks evolved from the now-extinct megalodon. More recently, in July 2023, a filmmaker working alongside a biologist captured what scientists believe may be the first-ever photograph of a newborn white shark off the coast of California. 

Staff at Atlantic Shark Expeditions use these shark jaws, a seal skull and a portion of spine as props when they educate visitors about great whites.
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Dubbed “great” for their size and power, white sharks can grow up to six metres — as long as giraffes are tall — and sport a girth of more than two-and-a-half metres. Females typically grow larger than males and hit sexual maturity late, at around 33 years old. While in utero, white shark pups are ovoviviparous, meaning they begin their lives gorging on their siblings (or half-siblings) while still in their mothers’ embryonic chamber: different pups from a single litter, typically numbering from two to 14, can have different fathers. When born, young white sharks are already more than a metre long and are abandoned by their mothers almost immediately. They feed exclusively on fish at first, their membrane-coated embryonic teeth growing longer and more pointed, then eventually broader and serrated as they age. Those teeth famously run through their mouths on a kind of cycling conveyor belt, with new replacements lurking in orderly rows, ready to emerge as old ones break or fall out and drift to the ocean floor. 

In what is now Nova Scotia, Indigenous Mi’kmaq have fished and hunted for swordfish and seals alongside the predators for millennia: shark teeth have been found in shell middens, evidence of the respect the creature’s power and presence garnered. “Our ancestors and the shark’s ancestor originally mingled together,” says Melissa Labrador, lead for Pemsik Mawa’tasikl Anko’tmu’kl and senior L’nu advisor on conservation and climate change for the conservation group Oceans North. “We’ve always had a relationship with sharks, but we’ve also understood healthy boundaries.” Back when her earliest relations travelled the ocean in birchbark canoes — which do, she laughs, resemble a “giant seal” — they took measures to avoid the chance of a negative shark encounter, including fastening spruce roots and seaweed to the vessels to mimic shallow waters. They knew full well, she says, the extent to which they shared their communal oceanic hunting grounds. 

Up to 100 million sharks are estimated to be killed by humans every year.

The earliest written documented white shark encounter in Atlantic Canadian waters was in 1874, recorded after a dory was mauled off Newfoundland’s southwest coast, leaving tooth fragments embedded in its hull. In 1935, a biologist reported an 11.28-metre “Man-eater” white shark that had been found dead and ensnared in a herring weir off New Brunswick’s Grand Manan Island five years prior. “From the liver,” his account goes, “210 gallons of oil were obtained.” Yet in total, according to the Canadian Shark Attack Registry, only three deaths have been attributed to white sharks in Canadian waters in the past 150 years. 

Atlantic Shark Expedition’s boat docked in Liverpool, N.S., with the shark cage and life jackets ready for guests.
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That there are dozens — possibly hundreds — of white sharks swimming in Nova Scotia’s waters and that it is possible to lure them closely enough to see one in person still seems inconceivable to many living here. From the 196T0Ks onwards, most Canadian marine biologists treated fishermen’s tales of encounters with great whites off Nova Scotia as anecdotal anomalies or old wives’ tales, largely missing Mi’kmaw traditional ecological knowledge linking the species to the larger Maritime coastal ecosystem. Still, rumours of shark encounters abounded on docks and in local bars: of a fisherman trying to land a giant bluefin on rod and reel, feeling the shudder of an impact through his line, only to discover a gory, serrated crater in the fish’s bulging belly; of surfers spotting a large grey dorsal fin slicing through the chop. “It was just a basking shark,” government biologists told them. But water users knew the frisson of fear sparked by a great white — the tell-tale fin, flashes of white underbelly, sometimes a rolling leap clear of the water, the ensuing carnage of a massive seal or tuna torn in half. 

Along with orcas, white sharks perch atop the Atlantic Ocean’s food chain, filling a vital ecological role akin to that of wolves in a forest. Just as wolves control deer populations, white sharks co-evolved with prey species that are often otherwise impervious to other threats. They hunt all regional species of seals, as well as rays and smaller sharks. They’re not picky and have been observed gorging on the fatty remains of dead whales. One biologist examining a dead shark near Deer Island, N.B., in 1971 found the tailless carcasses of three porpoises in its stomach. One fisherman told Gaetan he had seen a juvenile shark lunge and kill a deer swimming out to an island, and Gaetan says he saw the deer carcass — with teeth marks in it — for himself the next day.

Due to dropping numbers, white sharks were declared endangered in 2006 by the Committee on the Status of Endangered Wildlife in Canada and have been protected under the Species at Risk Act since 2011. But Crawford says the Canadian government has largely neglected the responsibility that should have accompanied the listing: providing stable and long-term funding for scientific efforts to try to better understand the northwest Atlantic white shark population, which could help make smart, locally responsive decisions to protect both sharks and human life. Instead, says Gaetan, the listing had the opposite effect, as Maritime fishermen grew reluctant to report sightings that could close their fishing grounds. 

Trackers like this one, held by research scientist and co-operator Neil Hammerschlag, can be attached to the shark’s fin.
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The tuna head he is tossing into the ocean has a camera line attached.
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But now, recent interest in the species, including widespread tagging and tracking of white sharks by OCEARCH, a U.S.-based research group, has started to draw back the covers on how many of the predators frequent Atlantic Canadian waters. Over five years, OCEARCH has tagged nearly 40 white sharks off Nova Scotia, making it possible to track individuals — including regionally named Unama’ki, Bluenose and Keji — online as they hunt and migrate up and down the eastern seaboard. Last year, for instance, a male shark named Breton, tagged in 2020, travelled in a large clockwise loop from Orlando, Florida, up to the mouth of the Gulf of St. Lawrence off Quebec, before detouring past Newfoundland to return to Florida’s balmy waters. 

This increased access and scientific interest has led to a rush of applications to Fisheries and Oceans Canada for permits to interact with white sharks. In 2023, the federal department issued five, including one to Atlantic Shark Expeditions. To draw the solitary creatures’ attention, it’s common for captains like Gaetan to hang bluefin tuna heads in the water column — doing what some call “provisioning” — which creates oily slicks white sharks can smell from kilometres away. This isn’t technically chumming, but Bradford says it’s one of her group’s major concerns. “There’s going to be a behavioural change because you are attracting sharks to your boat,” she says, adding that for a highly migratory species, the rules for the distances boats like Gaetan’s are expected to keep from local shores don’t mean much. “They want that oil slick to go as far as possible, which you can’t control. What’s the current doing that day? What are the tides? Where is that going to go? You don’t know.” Another concern, she says, is that as seal populations rise and ocean waters warm due to climate change, it seems inevitable that higher white shark populations won’t be far behind. 

The seas here are home to other shark species, too. Here, a blue shark eats a portion of the tuna head bait after swimming past the ASE boat.
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In November 2023, Melissa Labrador was leading an ocean conservation field trip along a Port Mouton beach, telling the group about her son’s long-time dream of seeing a shark eat a seal, when one suddenly caught their attention as it jumped and rolled out of the surf. Paying attention to small details, like seals coming up on the beach, can be a telltale clue there’s a shark around. In Mi’kmaw tradition, she says, the onus falls on humans to treat the predators respectfully — which may involve simply giving the creature its space. “Sometimes our curiosity gets the best of us, and we do end up interfering in a bad way and shift that balance in that relationship that the shark and his ancestors were used to,” says Labrador. “I’m not sure if cage diving, or things like it, are necessarily falling within that respectful boundary.” 

Deckhand Maggie McKenna prepares to deploy a floating seal decoy used to help attract great white sharks.
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For more than a year, alarmed by the number of sharks he’s seen swimming near popular beaches, Gaetan says he has asked Fisheries and Oceans Canada and the province of Nova Scotia to install signs warning of the risks of shark attacks. “Some of the areas that we’re in now — it’s very hot with populations of white sharks, and there are beaches that are literally not even a half-mile away,” he says. Like other shark enthusiasts, he doesn’t like the term “shark attack,” likening white sharks more to curious dogs than vicious predators. “When a dog sees something he doesn’t understand, he’ll go over and nibble on it. Sharks are the same,” says Gaetan. “Unfortunately, when they nibble, they’re punching holes in you.” 

Weeks after the attack on Pepper, news of the dog’s death reverberated across the province. The event was unprecedented on Nova Scotia’s south shore. In the aftermath, Crawford spoke with the dog’s owner and learned of another hunter who had seen four white shark breaches over six hours in a similar area the next day. Breaching is exceptionally rare in the northwest Atlantic, he says, and increases the probability of a previously unknown white shark mating zone in the area. Given “the serious human risks posed by the recent intense white shark activity” and “the persistent reluctance of federal, provincial and municipal agencies in Atlantic Canada to take action about shark public education and risk management,” Crawford went so far as to issue his own advisory on a shark email list he operates and encouraged locals to print and post signs along wharves and popular beaches. “Like our American cousins along the New England coast, Atlantic Canadians need to have trauma kits with tourniquets at each and every single swimming beach,” he says. “The vast majority of Canadians will never see the air bag in their cars, but they are damn glad to see that air bag when it matters the most.”

Overall, as a society, “we’ve given ourselves this illusion that the beach is safe,” says Ret Talbot, the co-author of Chasing Shadows, about American biologist Greg Skomal’s decades-long career studying great whites. During his reporting, Talbot asked an official with the United States’ National Park Service if they planned to install any real-time receivers along the tourist-frequented beaches on Massachusetts’ Outer Cape. “She basically explained to me that it really came down to the question of liability,” he says. “None of these systems have a 100 per cent success rate.” In an email, a spokesperson for Fisheries and Oceans Canada didn’t answer a question about signage but did say white sharks “can be anywhere along the coasts in Atlantic Canada, especially in the summer months” and that water users should always keep an eye out for shark activity. 

The shark cage is visible on the deck as the ASE vessel steams past a headland on Nova Scotia’s south shore.
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Pepper’s owner, who requested anonymity to avoid media harassment, says he remains concerned about local surfers, paddle boarders and kayakers in shallow water close to shore. “I hope people are beginning to realize how many of these sharks are present in our waters,” he says. “I never could have imagined this kind of thing would happen.”

For now, Crawford, Bradford and others say they will keep sharing information, sightings and knowledge about the species as they anxiously await meaningful government leadership and public education around shark safety, as well as more funding for research on the fundamental science of white shark ecology along Nova Scotia’s shores beyond the work of private charters like Atlantic Shark Expeditions. “Clearly, Canadian and U.S. government agencies and research scientists need to give their collective heads a big shake,” says Crawford. “If they are not proactive in monitoring, understanding and communicating knowledge associated with white shark social interactions with humans, then residents and visitors to the northwest Atlantic will continue to be exposed to needless risks.”

Meanwhile, slicing through dark Maritime waters searching for its next meal, a great white shark remains neither victim nor perpetrator. A shark is simply a shark.


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