WARDENS believe that North America's largest freshwater turtle has defied the British weather and survived in a Caldicot park for ten years.

The alligator snapping turtle is commonly found in the Mississippi river, but Caldicot Country Park head warden Denis Manning has seen one grow to have a shell of 15 inches and tail of eight inches long after dividing its time between the River Neddern and one of his ponds.

Mr Manning said: "I didn't think it could survive here because of the cold winters, so this is quite a rare beast.

"I first saw it ten years ago when an excavator was digging in the river and we noticed something wriggling in the bucket.

It was ten inches long then and even bigger a few years later when someone said they'd seen a dustbin lid walking along the path."

The creature which is a scavenger and survives off anything from fish, invertebrates and amphibians can live for 150 years and is known to take a particular liking to ducks.

The 181lb creature - whose sex hasn't been identified - was caught by Mr Manning and is being taken to a sanctuary in Cardigan as the Tortoise Trust find it a new home.

The Tortoise Trust director Andy Highfield said: "We will take a look at it to determine if it is definitely an alligator snapping turtle or a common snapper.

"But both have been imported as pets and sold as babies when only a couple of inches long.

"But of course they get bigger and some people can't manage them. Then they are unfortunately and illegally dumped in ponds and rivers which is probably what happened in this case."

Mr Highfield isn't surprised that the creature has survived as it has moved into cold climates in Canada which are much more severe than the UK winter.

But he believes the weather here probably wouldn't have been sufficiently warm for a pair to breed.

"We will collect the turtle and keep it in a holding pond with a nice temperature before our vet checks it.

Then it will be rehoused to one of our members in a secure fenced pond area," Mr Highfield added.

Alligator Snapping Turtle facts:
  • The turtle's characteristic large heavy head, long thick tail and three dorsal ridges give it a primitive appearance that some experts believe is reminiscent of some of the plated dinosaurs.
  • There is an unconfirmed report of a 403 pound creature found in the Neosho River, Kansas in 1937.
  • The creature is a scavenger and opportunist carnivore and will eat almost anything that it catches.
  • An alligator snapping turtle appears in the movie Teenage Mutant Ninja Turtles Two: The Secret of the Ooze. A turtle mutates into a giant villain called Tokka.
  • Weighing in at 18 pounds, the alligator snapping turtle is nearly three times the weight of Charlotte Church and Gavin Henson's new baby Ruby Megan Henson.