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various reports from shark bite injuries and a spate of sightings of the marine predators off the Northeast coast of the United States have rattled summer beachgoers.
But are New York’s Long Island and? Cape Cod, the Massachusetts peninsula, where many of the recent suspects shark encounters have taken place, experienced something out of the ordinary? Yes and no, according to Gavin Naylor, director of the Florida Program for Shark Research at the University of Florida in Gainesville.
Global shark attacks are at a similar level to previous years, said Naylor, who is also a curator at the Florida Museum of Natural History, but there are signs that the US northeast coast could see a revival.
“We are totally in fashion for this time of year. I think globally we usually get between 70 and 80 unprovoked bites from sharks around the world. But that is a global phenomenon. And it’s being distributed in a patchy way,” Naylor explained.
“One year we might have two or three bites in Hawaii in quick succession. Next year it could be New Caledonia; it could be in Western Australia. And this year it’s off the coast of Long Island.”
Naylor declined to provide totals for the year so far because it takes time to investigate and verify reported bites. (Naylor’s work at the Florida Museum of Natural History includes tracking data on shark attacks.) Last year there were 73 confirmed unprovoked shark bite cases – in line with a five-year average of 72 incidents per year. However, there were 11 fatalities from sharks, an increase of an average of five per year.
The sharks that swimmers encountered off Long Island were foraging for food, not targeting humans, Naylor explained. Most have been identified as sand tiger sharks, Naylor said, which, while fearsome-looking, aren’t considered aggressive. They probably ventured into inshore waters to hunt abundant schools of baitfish close to shore.
The schools were particularly dense this year because of the warm ocean currents peeling off the Gulf Stream into the Atlantic and extending along the northeast coast, he explained. These waters are richer in chlorophyll, which allows plankton to thrive, which also attracts baitfish.
“These baitfish are in schools of hundreds of thousands — or millions,” Naylor said, “and when they get pretty close to shore, the sharks follow them.
“The sharks are swimming around trying to chase their dinner. The people splash around with beach balls in their circle. … The surf zone gets pretty cloudy from all the energy and the sharks are all ringing because they’re excited to see all this food – every once in a while they make a mistake.”
Contributing to the problem is a sand tiger shark nursery, discovered in 2016, off the coast near the coastal waters of Long Island’s Great South Bay, where sharks from several months to 5 years old feed and grow. (The sharks are born off the southeastern coast of the U.S. before migrating north and spending their summer in New York waters and returning south again in the fall, according to the Wildlife Conservation Society.)
Unlike adult sand tiger sharks, which are up to 2.7 meters in length, the 4- to 5-foot-long (1.2 to 1.5 meters long) juveniles can move closer to shore to chase fish.
“As you can imagine, (same) with all mammals, juveniles aren’t as experienced. They don’t have as many pattern recognition skills as adults,” Naylor said. and what a flash of the scales of a bony fish is.
“You have a bunch of teenage sharks and they’re running around chasing fish.”
At Cape Cod, where several great white sharks have been spotted this summer, a different dynamic has been at play, leading to the closure of at least one beach. Naylor said there are no reports of shark bites to his knowledge.
In the summer and fall, white sharks hunt seals — their favorite prey — along the region’s coastline, allowing them to get close to popular beaches. Based on tag data from 14 sharks, a study published last year in the journal Wildlife Research found that they spent nearly half their time at depths of 4.6 meters or less. This means that there is great potential for their presence in recreational waters frequented by swimmers and surfers.
“Until now, we didn’t know how much time they spent in shallow water close to shore,” lead author Megan Winton, a research scientist at the Atlantic White Shark Conservancy, said in a press release last year. Based in North Chatham, Massachusetts nonprofit provides funding and resources for scientific research to improve public safety.
The population of great white sharks off the coast of Cape Cod has increased along with the local seal population, which recovered in the decades following the Marine Animals Protection Act of 1972.
It is the only place in the Atlantic Ocean where white sharks congregate. To date, about 300 white sharks have been identified and tagged by researchers, but there is no official population estimate yet.
Since 2012, there have been four unprovoked white shark attacks on humans along the Cape Cod coast, including one fatal attack. in 2018, the first in Massachusetts since 1936.
No matter what kind of shark, Naylor said the measures to protect yourself are similar: Don’t swim or surf alone, and don’t swim near large schools of fish or if you see seals nearby. Do not wear jewelry in the water that could mistake a shark for the glint of fish scales. If you see a shark, slowly get back out of the water. Don’t panic and splash around.