Cabot off Nova Scotia in 2018. Picture: Ocearch/Supplied via Reuters

North Carolina - Cabot's 500 pounds of churning white flesh sped though North Carolina waters last week, part of a group traversing shipwrecks, seeking bounties of fish.

In a matter of days, Cabot travelled hundreds of kilometres north, sliced through Block Island Sound and on Tuesday hunted for a meal near Greenwich, Connecticut.

"For the first time ever, we are tracking a white shark in the Long Island Sound," the ocean life research group Ocearch said on Twitter.

Later, the group clarified its tweet and said it was the first time a shark of Cabot's size and maturity was tracked there. It detected a juvenile shark in the sound in 2016.

But beachgoers panic-stricken over a Memorial Day weekend "Jaws" scenario should feel comforted by Cabot's presence, which indicates cleaner waters full of the sea life that drew him in the first place.

Ocearch, which has tagged 43 sharks, outfitted Cabot with a tracking device last year in Nova Scotia.

Cabot's journey up and down the coast is typical for sharks pursuing warm waters. The 3 metre shark ripped down the Eastern Seaboard after he was tagged in October and reached Florida waters around Christmas, according to tracking data.

After a jaunt into the Gulf of Mexico, Cabot reversed course and headed back north in the summer. In just over three months, Cabot has travelled more than 6 400 kilometres.

"These sharks have been coming here for a millennia; for as long as the East Coast of the US has existed, these sharks have been in their waters," Robert Hueter, a senior scientist at Ocearch, told CBS News last week.

Chris Fischer, the group's founding chairman and expedition leader, said the group was surprised to see Cabot so far west, CBS News reported, and speculated his presence was linked to environmental efforts to clean up the sound.

"This is something to celebrate," Fischer said.

"I know they've been working hard in the sound to clean it up and to get life to come back to the region, and when you have an apex predator like Cabot move in to the area, that's a sign there's a lot of life in the area and you've probably got things moving in the right direction."

Soaring population growth, climate change and sewage have harmed the waters, but a 10-year effort by federal and state officials to clean up the region appears to have yielded promising results, the Journal News reported, citing a report from the environmental group Save Our Sound.

Cabot left the sound by Monday evening and ventured southwest of Montauk, according to tracking data. He seems to be the northernmost great white tracked by Ocearch. Brunswick and Jane recently pinged from the North Carolina waters, and Lunda, a 950kg shark, was off South Carolina recently.

Far northeast is a fitting place for Cabot. He was named in honor of John Cabot, the 15th-century Italian explorer who sought a route to Asia.

Instead, he spotted rocky terrain on his voyage west in 1497 - and called it Newfoundland.

The Washington Post