Stony Brook scientists say more research is needed to explain rise in shark encounters in region

After a spate of reported shark bites this summer — at least five off Long Island, plus one off Rockaway Beach that left a woman in critical condition — some scientists say more research is needed to ensure “safe and sustainable coexistence” for humans and the apex marine predators. 

In July, Gov. Kathy Hochul told reporters the apparent spike had to do with cleaner nearshore waters drawing schools of bait and bunker fish that sharks feed on. But explanations like climate change and shifts in the shark population and their prey haven’t yet been backed up by data, Stony Brook University scientists Oliver Shipley and Michael Frisk argue, along with partners in other institutions, in a paper recently published in the Journal of Fish Biology.

“We don’t have particularly good historical information on really anything related to shark biology, despite the fact that every summer these animals use New York waters for various reasons — foraging, potentially reproduction — and have been doing it for millennia,” said Shipley, a research assistant professor at Stony Brook’s School of Marine and Atmospheric Sciences. 

Science behind shark encounters

The lack of data may contribute to the spread of misinformation, misguided management and bad outcomes, the paper’s authors argue. 

The spike in regional shark encounters does appear to be real, even if its significance is unclear. Between 2018 and 2023, New York State environmental officials recorded 17 “negative human-shark interactions.”

Before 2018, there were just four confirmed, unprovoked incidents in the region dating to 1873, according to a database, the International Shark Attack File, maintained by the Florida Program for Shark Research at the Florida Museum of Natural History. 

The regional increase occurred amid a global drop in shark bites, said Gavin Naylor, the program director. But Naylor said it was difficult to say if the numbers were statistically significant. “It’s like looking at rainfall: One part is inundated, [and] 10 miles away is completely dry,” he said. 

From a public health standpoint, he said, “There are so many far more pressing problems to society than the very rare incidence of shark bites.”

That risk is about 5 million to 1, but fear of shark attacks, sometimes amplified by media attention, tends to redound badly for the sharks, Shipley said, citing a history of overreaction by humans, including vigilante shark-killing.

The Stony Brook paper calls for closer surveillance of waters shared by sharks and bathers with drones and acoustic tags tracking shark and prey, along with monitoring of the effects of climate change. 

Warming waters of the North Atlantic and the New York Bight, the ocean region off Long Island and New Jersey, appear to have expanded the range of some shark species such as the once-tropical blacktip, but contracted the range of others such as blue sharks and porbeagles, the paper said. Climate change also might play a role in the nearshore appearance of schools of menhaden that might draw sharks in pursuit, the paper’s authors write, but shifts in the abundance of fish in local waters also could play a role. 

Much is still unknown about shark distribution and shark attacks, a relatively small area of research. 

Scientific surveying of the Atlantic coast shark population historically has taken place, mostly south of New Jersey, making it difficult to make inferences about local populations, and general statements about the shark population increasing or decreasing are nonsensical, the paper argues, because the numbers of various shark species don’t necessarily move in tandem. More than a dozen species of shark frequent New York waters during the summer. 

For the 17 recent negative human-shark interactions in the region, scientists were only able to confirm the species of shark in one incident, which they did by analyzing the DNA of a recovered tooth. They concluded it was a “subadult sand tiger,” according to the paper.

More sharks, more beachgoers

Tobey Curtis, a National Oceanic and Atmospheric Administration fishery management specialist, said the data picture was not all bleak, though it might be hard to draw many conclusions about what he said was the essentially “random” nature of bites. 

“There is plentiful empirical evidence that a number of species, Atlantic-wide, are increasing” after 30 years of NOAA’s population management, Curtis said. Sandbar, dusky, white, blacktip and smooth dogfish species, all found in New York, are increasing their numbers after overfishing in the 1980s and '90s, he said. 

There is also “ample” evidence to suggest that climate change may be leading to more interactions, with species such as blacktips spending more time in New York waters because of longer summers before migrating south, he said. 

Beach attendance, which has increased in recent years, also likely plays an important role, he said. Jones Beach alone now draws more than 8 million visitors annually. 

“With more people in water and a rebuilding of the natural ecosystem, you’re going to have people and sharks sharing the same space at the same time more often,” he said. People will continue to get bitten, Curtis said.

Some of the observation Shipley and his colleagues call for is already underway.

Lifeguards and drone pilots now monitor about a dozen miles of state beaches on Long Island and have in the past three years seen not just sharks but a “tremendous amount” of baitfish close to shore, said George Gorman, Long Island regional director of the New York State Office of Parks, Recreation and Historic Preservation, which manages the beaches.

“We have seen dolphins, we have seen stingrays, we have even seen whales in greater numbers closer to shore,” he said. What’s bringing the baitfish so close is unclear, he said, but his agency is sharing data collected from the drone flights with the New York State Department of Environmental Conservation and research institutions. 

In coming years, said Naylor, of the Florida Program for Shark Research, shark watch could become as much a part of beach life as rip current warnings are now, with continued drone flights, observation by specially trained lifeguards and medical training. Even if sharks are not a public health risk, “from a tourism perspective, they are a concern,” he said. 

Partnering with fishermen on shark research

Beachgoers and officials are not the only humans with a stake in the issue, though. Bonnie Brady, executive director of the Long Island Commercial Fishing Association, an industry group, said some earlier marine research, like placing acoustic monitors in squid fishing grounds in Long Island waters, has interfered with her members’ work. 

“The ocean isn’t a dumping ground where you can throw whatever you want in the name of science,” she said. Any new research should “partner with commercial fishermen so their traditional and historical knowledge is taken into account and position them in such a way that there aren't inherent conflicts or dangers to fishermen who have been working these waters for decades.”

Robert Aaronson, a commercial fisherman who also runs a charterboat, OH Brother, out of Montauk, said he’d seen “a lot” of sharks in nearshore waters in recent years, along with other predators like tuna and prey like mackerel, menhaden and seals. 

“You can’t guess like a fish,” he said, but “sharks are attracted to commotion” and will hunt baitfish pushed up against the shore. He said the number of sharks might have ballooned because of regulations on taking them.

Bathers should “pay attention to birds, fish flashing” on top of the water and feeding blitzes — all signs that there is prey to be had, with sharks perhaps on their way, he said, though “people sometimes aren’t smart enough to stay out of the water.”