A popular serpentine sculpture embedded in a salt lake in South Australia's mid north has been vandalised, much to the dismay of the local community.

The creature, known as the Lochiel Ness Monster or Loch Eel, has been a tourist attraction near the small town of Lochiel for more than 30 years.

Made from old tyres and pipes, it has sat proudly in Lake Bumbunga, also known as the pink lake, and is clearly visible from passing cars on the Augusta Highway.

But within the past fortnight unknown vandals have stolen its head, leaving only the tyres that make up its arching body.

"People flock to the lake because that's the big drawcard," said Vickii Myhre, who operates the nearby Jitter Bean Oasis cafe.

"We hear the stories of older couples and they say 'we used to drive past as kids'.

"It's a shame it's just gone, someone's taken it. It would be of no use to anybody."

The Loch Eel is often jokingly referred to as an Australian cousin of the Scottish monster Nessie.

The legend of the Loch Eel dates back to the 1800s, one local said. ( Facebook: Greg Simmonds )

The sculpture's appearance in the lake is shrouded in mystery, and it seems to have moved in overnight.

"It just arrived out there one morning. It was there," said local John Nicholls, who hinted that he knew a little bit more about the monster than he was prepared to divulge.

"There was a little sign put on the side of the highway... and since then a carpark has arisen near it and then we've had to fence it off because the thing we hate most is people driving on the lake."

Despite reports it had been created in the early 1970s, Mr Nicholls said the Loch Eel was actually a creature of the mid-1980s.

"It's alongside Highway One and I would imagine that for years there have been kids from the west coast and north of here who fight each other to see it first," he said.

Mr Nicholls said the myth of a Lochiel monster is part of the local folklore and dates back to the 1800s.

The legend is linked to a bullock team that disappeared in the lake's treacherous sands after allegedly being spooked by something.

Headless monster won't stay like that for long

The monster's home, Lake Bumbunga, is used by company Cheetham Salt for salt harvesting.

The Lochiel Ness Monster is also known as the Loch Eel. ( Facebook: Greg Simmonds )

Ms Myhre said locals were "ropable" at the theft, and said she first found out about it a couple of weeks ago.

"I actually got a call from a group of photographers from Adelaide, and the lady said we've come this way because they wanted to get the pink lake with the Loch Eel," she said.

"They said that the head was gone. There's just a branch stuck there."

But Mr Nicholls said he did not expect the creature to remain in its current state for long, and thinks a new head will spring up soon.

"It's not fair to leave it like that. The headless monster — that's creepier," he said

"We'll have to have a talk and I guess somebody mysterious again will come up with it.

"Some arsehole has pinched it. It'd be a passer-by. Geez, if the locals had wanted to pinch it they'd have done it bloody years ago."