“There are more white sharks off the coast of Massachusetts, and specifically off the coast of Cape Cod, than there were twenty years ago,” Greg Skomal, a senior fisheries biologist with the state’s Division of Marine Fisheries and a leading expert on white sharks, said. “That’s what you expect when you restore an ecosystem.”
White sharks once dominated the waters around Cape Cod, but scientists believe recreational fishers looking for a big catch and accidental catches by commercial tuna and swordfish fisheries are to blame for their decline. The white shark population in New England dropped by 63 to 73 percent during the 1970s and 1980s, according to scientists.
At the time, many saw sharks’ disappearance from the waters as a boon for humans. “Jaws,” which premiered in 1975, left many viewers terrified of encountering the animals on a swim.
“The perception at the time of ‘Jaws’ and even prior to ‘Jaws’ was that the only good shark was a dead shark,” Skomal, who wrote a book on the history of shark research, said.
But without white sharks, the ocean’s natural food chains are thrown off balance, leading to the proliferation of certain species of fish as others languish, like the coral reefs and kelp that fish eat.
In 1993, the National Oceanic and Atmospheric Administration (NOAA) implemented the first management measures for Atlantic sharks, including a prohibition on removing their fins. A turning point came four years later, when white sharks were marked as a prohibited species for harvesting.
Although scientists cannot pin down a direct cause of the population recovery, the increasing numbers of sharks are correlated with the implementation of shark management plans and the growing population of grey seals, their prey. Congress banned the killing of seals under the Marine Mammal Protection Act in 1972.
Around 800 white sharks visited the waters off Cape Cod from 2015 to 2018, according to the Atlantic White Shark Conservancy (AWSC). Although scientists do not know how many sharks frequented the coast before that, they said the number generally indicates the species is recovering in the region.
“We don’t have that magic number of ‘this is the perfect ecosystem,’” Ashleigh Novak, a research coordinator at AWSC, said. “But what we do know is that from these protective measures for seals and sharks we’re seeing them begin to recover.”
It’s hard to miss the sharks’ return to Cape Cod from the shore. Beachgoers spot their unmistakable fins in the waters each year and take precautions to avoid the animals, which have become a normal part of swimming in the ocean.
Skomal believes people’s warming attitudes towards sharks represent a transformative change for marine biology.
“I think this prevalence of fear in the seventies that persisted for, perhaps, another decade or so has morphed into fascination,” he said.
It certainly did for Skomal, who saw “Jaws” with his friends in Fairfield, Conn., when he was 13 years old. He remembers watching Richard Dreyfuss as shark expert Matt Hooper, who came to Amity Island to “solve the shark conundrum.”
“I thought it was like, the most amazing film,” Skomal said. “I was inspired by that and decided really at that age that this was something I wanted to go into for the rest of my life.”
At the time of the film’s release, researchers largely studied how the “man-eaters” attack humans, as scientists referred to sharks in scientific papers. A new generation of biologists has expanded humans’ understanding of the species “by orders of magnitude,” including how they grow, reproduce, and most importantly for humans, feed, Skomal said.
Skomal studies white sharks’ predatory behavior when hunting grey seals for insights into how to keep humans safer in the ocean. He uses video cameras mounted on sharks’ bodies and accelerometer tags, which measure movements like tail-beat frequency and swimming depth, to understand when, where, and how sharks hunt their prey.
“We could take that information and translate it into recommendations for the public,” Skomal said.
The National Park Service offers safety guidance for visitors to Cape Cod, including tips to stay close to the shore, swim in groups, limit splashing, and avoid areas where seals and schools of fish are swimming.
Endurance swimmer Lewis Pugh wants to see humans and sharks coexist in the ocean. In May, he swam sixty miles around Martha’s Vineyard, where “Jaws” was filmed, to help change people’s attitudes from fear to a healthy respect for sharks.
He considers the Shark Swim a step towards undoing the film’s lasting negative impact.
“It shaped the narrative about sharks for the past fifty years, no question about that. It created a culture of fear around the world,” Pugh said.
Vendetta killings, shark-fishing tournaments, and commercial shark fishing proliferated in the decades after the film’s release.
“There was a lot of fear around sharks resulting from them watching ‘Jaws,’ and there were shark tournaments,” said Novak, referring to fishing competitions where participants try to catch the biggest shark.
“There is this really big public perception shift that has happened in the last fifty years.”
Pugh’s swim sought to raise awareness of the more than 100 million sharks killed globally every year, despite increased research showing that sharks are vital to healthy marine ecosystems.
“It is complete madness. It is ecocide that is happening right now,” he said. “I think we still have quite a long way to go to educate the public about how important they are.”
Pugh, who has crossed the Red Sea and swum the length of the Hudson River, could not help but feel a touch of nervousness before getting in the water himself.
“I’m doing interview after interview after interview speaking about sharks, and then I have to get in the water and I’ve got to swim,” he said.
Jade Lozada can be reached at jade.lozada@globe.com.
