Great white shark spotted in Long Island Sound for first time ever: Researchers The Great white shark measures nearly 10 feet long, researchers said.

A sub-adult great white shark measuring nearly 10 feet long has been tracked in Long Island Sound off the Connecticut shore for the first time ever, marine researchers said on Monday.

The great white was being tracked Monday by the ocean research group Ocearch, which has been tracking the shark since last year, Chris Fischer, founder of the research group, told ABC News.

"Be advised! For the first time ever, we are tracking a white shark in the Long Island Sound," Ocearch researchers tweeted Monday

Fischer said the shark measures 9-feet 8-inches and was spotted off the shore of Greenwich, Connecticut.

"He was right up on the beach, very close," Fischer told ABC News.

He said his group first spotted the great white in Nova Scotia last fall, where he was pulled from the water, tagged with a tracking device and released back into the wild. He said his research team named the shark Cabot after the Italian navigator John Cabot, who explored North America in 1497 under the commission of Henry VII of England.

"To see him that deep into the Sound I think that that is a fantastic sign for the region and really interesting development for us because we just haven't seen them that deep into the Sound previously," Fischer said.

He said the presence of the shark in Long Island Sound indicates an abundance of sea life in the area for the predator to feed on.

"I think it's a really great sign for the Sound because these white sharks only go where there's an abundant amount of life, where the water is in pretty good shape," Fischer said. "That's a real positive sign for the Sound there."

He said that previously his group has only spotted a baby white shark just outside the mouth of Long Island Sound, just north of Montauk.

Since Ocearch has been tracking the Cabot, the great white has traveled all the way to Florida.

"Now he's making his way back north, probably back to the Nova Scotia region," Fischer said. "Something got his attention and brought him into the Sound to have a look."

He said he didn't believe there was any imminent danger for swimmers in the area, but cautioned that people should "demonstrate common sense" before going into the water.

Fischer said he suspects Cabot is just making a pit stop to feed on what is in the area, before heading back out to deep water and continuing north.