A Town of Hempstead lifeguard first reported seeing a significant sized shark by a lifeguard on a surfboard. They weren't sure of the exact size.
The Town of Hempstead contacted Long Beach, Jones Beach and all the beaches along the south shore.
Then, a second shark was spotted in the water near the Town of Hempstead beaches, officials say.
Lifeguards have red-flagged the strip of water as per the New York State shark protocols.
Due to the second sighting, swimming remains prohibited at certain Town of Hempstead Beaches: Civic Beach, Lido Beach, Lido West Beach, Town Park Point Lookout and Town Park at sands.
Siena Diaz was one of several swimmers who were ordered to get out.
"I noticed people backing out and I was okay, I'm going back out too," Diaz said. "It's a good thing I got out."
Diaz didn't see the shark, but lifeguard Logan Fitzgerald did, and it was bigger than he was.
"It shot out of the water, but definitely spun around," Fitzgerald said. "Definitely dorsal fin, that wasn't curved straight up. Not a dolphin, definitely a shark."
Another lifeguard confirmed the sighting, and identified it as a bull shark -- a species that can grow to 8 feet in length and is known to be particularly aggressive. Authorities released a photo of a sea ray that washed up with enormous bite marks.
"By the shape of the head, shape of dorsal fin, fitness of the body, we determined it as a bull shark," Chief Town Lifeguard Mike Romano said.
The water temperature is now close to 80 degrees, and experts believe sharks are moving closer to shore in search of food.
There have been 19 shark sightings in New York in the past 12 months.
With more people boating during the pandemic, the thinking is that's why there's been more reported sightings, while the actual number of sharks in the water is likely similar to previous years.
Lifeguards will continue to monitor the situation and determine when it is once again safe for swimming to resume.
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