With the attacks over the weekend, the two-year total for the state stands at 13, more than have been reported in the past 175 years, research from the Atlantic Shark Institute shows.

"To see this many this quickly this early in the season, not withstanding last year, I'm surprised," George Gorman, the institute's director, said on Wednesday.

The first attacks occurred early on Monday evening, when a 15-year-old boy surfing near Fire Island was bitten on his heel and toes. He was hospitalized with non-life threatening injuries, Suffolk County Police said.

The second incident, also on Monday, took place at Robert Moses State Park, about seven miles (11.3 km) away from the first. A 15-year-old girl suffered three puncture wounds on her left leg.

On Tuesday, two men were attacked in separate encounters, one at Quogue Village Beach in the Hamptons, and the other near the sight of the first attack. Neither sustained life-threatening injuries.

The species believed to be responsible is the sand tiger shark, Marie Levine, executive director of the Shark Research Institute, said.

"It looks like sand tiger sharks, because of their dentition and they like to be close to shore, where they're hunting fish," she said, referring to bite marks on the victims.

Around 50 sand tigers were spotted by drones off Long Island on Tuesday, and swimming in the vicinity was forbidden for more than an hour.

Experts say sand sharks have moved closer to shore in recent years because warmer ocean temperatures have brought their prey into shallower waters close to land.

While no other attacks were reported over the weekend, shark sightings were reported in Florida and Massachusetts. Video footage from Pensacola, on Florida's Panhandle, showed startled swimmers rushing ashore on Sunday as a black dorsal fin and tail cut through shallow waters.

Despite increasing sand tiger shark attacks, the species has never killed a human, experts say. But other, more deadly species have also migrated into northern waters in recent years. In 2020, a great white shark killed a Maine woman in the first reported shark attack in that state's history.

(Reporting by Rachel Nostrant; Editing by Sandra Maler)

By Rachel Nostrant