A 16-year-old boy who was bitten in the leg by a shark off Adelaide’s coast has been left with “big gashes” but is doing “fine”, his family says.

Nathan Ness was on a fishing boat with his brother and sister when they caught the shark, believed to be a young great white, about 1:40pm. 

His father Michael Ness, who was also on board, said he removed the hook from the animal’s mouth and that they were about to throw it back when it suddenly turned around and snapped.

The boy was bitten in the leg and has been taken to hospital.(Supplied)

“We were out fishing and Nathan hooked up to a big shark. He reeled it up to the boat and we hauled it into the boat just to get the hook out and I grabbed a pair of pliers, ripped the hook out of it,” Mr Ness said.

“Then he picked it up to throw it back into the water and take a picture of it and as he picked it up, it swung around and grabbed hold.”

Michael Ness said that, despite a couple of gashes, his son was fine.(ABC News)

The teenager was bitten in the lower leg by the shark, which was estimated to be about five feet in length.

“I reached down then and opened its mouth and the shark let go and he hauled it up and threw it back in the water,” Mr Ness said.

He expressed relief that the outcome wasn’t worse, saying his son was doing well, considering what had occurred.

“He’s fine, he just needs stitches. He’s got big gashes in his leg,” he said.

‘The kid is lucky’

Paramedics were called to the West Beach boat ramp about 1:40pm, and the SA Ambulance Service (SAAS) said the boy would be treated in hospital.

Nathan’s brother Eric and sister Megan at the West Beach boat ramp.(ABC News: Olivia Mason)

Nathan Ness’s sister Megan said her brother had been left with minor flesh wounds, and the shark had taken a small “chunk” of his skin.

“He thought it would be cool if he held the tail so he could get a photo with it, and then the shark turned around and bit his leg,” she said.

“There were only about three cuts, he’s going to need to get stitches though.

“First he probably got shock, he was like ‘get it off, get it off’.”

The incident happened off West Beach.(Supplied)

She said they initially thought it was a Mako shark, but later found out it was a great white.

Fishermen Brodie and Colin North said it was unusual to catch sharks in waters off West Beach, and said the incident could have been much worse.

“They’re lucky they got away with a few stitches considering the size of the shark and how aggressive they are when they’re pulled onto a boat, especially given there were three children on board,” Brodie said.

“The kid is lucky he didn’t get bitten on a main artery.”

Emergency services were called to the West Beach boat ramp after reports of a person being bitten.(ABC News: Olivia Mason)

“I’ve never seen anyone pull up a shark of any kind here,” Colin North said.

“My word he was very fortunate.”

There have been several shark attacks — three of them fatal — in South Australian waters in the past 12 months.

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