Old Bar road bike racing star, Josh Hook, discovered the turtle entangled in rope while fishing several kilometres off Wallabi Point the day before it was found washed up on Old Bar Beach.

"I was cruising back to Forster in the boat and just saw this thing in the distance and that was it," Josh said.

"It must've suffocated. The rope was wrapped around it five times."

Josh said it was entangled in some kind of homemade contraption that looked like it had been put there to attract fish.

Realising the turtle was dead, he untangled the creature before continuing on his way.

Hunter Local Land Services marine and estuary officer, Brian Hughes, believes the contraption Josh described was a fish aggregating device (FAD), which is a man-made object placed in a particular location to attract fish.

While he said FADs could often be useful tools for marine management, he was disappointed to learn that a homemade device that had been placed there with no thought for the safety of other creatures had caused the death.

But he admitted it was a consolation to find out how the turtle died.

"It's always good to know what the cause of death was," Brian said.

"We'll record the information in the database and pass it on to National Parks."

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Josh said it was disappointing that his first encounter with a turtle of that size (it was measured at 2.1 metres in length and estimated to weigh hundreds of kilograms) happened under such tragic circumstances.

"It's never good to see things like that," he said.

He hoped the incident would serve as a timely reminder to people to be more responsible with the things they put in the ocean.

"Just think twice next time you go to put something in the water," Josh said.

"You've got to make sure it's done properly and to the rules. This thing definitely wasn't to the rules."

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