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Mystery 23-foot sea beast weighing four tonnes found on beach in Wales

Scientists will investigate a mysterious marine beast that is more than 23 feet long, weighs an estimated four tonnes, and has no face in order to determine its true identity.

Scientists sent samples to specialists at the Natural History Museum and London Zoo in a bid to identify the creature (Image: Credit: Marine Environmental Monitoring via Pen News)

The massive beast was discovered on Broad Haven South Beach in Pembrokeshire, Wales, and reported to the UK Cetacean Strandings Investigation Programme (CSIP).

However, because the gloopy bones were already degrading, scientists were unable to make a definitive diagnosis, and a sample from the marine beast must now be sent for testing.

Matthew Westfield, the CSIP stranding co-ordinator for Wales, said: “It’s very difficult to tell for certain what it is because it’s so badly decomposed.



“It died at sea and had been dead for a while before it washed up on the beach, so it would have come in with one of the high tides.”

Investigators discovered the sea beast after a woman reported ‘a blob’ washed up on the beach in Pembrokeshire ( Image: Credit: Marine Environmental Monitoring via Pen News)

The remnants are depicted in photos from the scene as a grey husk, stringy in some places and bony in others.

With the skull missing and no limbs visible, no evident trait of the creature’s biology shines out.

And though Mr Westfield identified a spine, measuring some 23 feet long, even the animal’s true scale is uncertain.

Scientists have sent samples to the Natural History Museum and London Zoo ( Image: Credit: Marine Environmental Monitoring via Pen News)



The team are working to uncover its true identity ( Image: Credit: Marine Environmental Monitoring via Pen News)

He said: “Basically the whole head element was either decomposed or missing or pointing in the wrong direction.

“We were unable to say, ‘right, there’s the head element of it’ so we suspect it could have been longer.”

However, inspecting the remains in person did offer some clues.

Matthew said: “Basically I got a report of a blob, a huge thing that washed up on a beach.

Some pictures show the remains as a grey husk while others show bony elements ( Image: Credit: Marine Environmental Monitoring via Pen News)

“And the lady that actually reported it to us had done a bit of research and had initially come back saying that she thought it might have been a basking shark.



“Well by the pictures we initially didn’t think so because of the size of it and because it is rare to get basking sharks wash up on the beaches around Wales.

“So initially we thought it was going to be a whale but when we actually got there and did an exam on it, it became clear that it definitely wasn’t.

“The initial clue was the smell of rotten fish. Decomposing fish smell different to decomposing whales.

Experts say they will likely never know what killed the sea beast ( Image: Credit: Marine Environmental Monitoring via Pen News)

Mr Westfield believes the remains could be of a basking shark ( Image: Credit: Marine Environmental Monitoring via Pen News)

“Then we got closer and we had a look at the bone structure which indicated that it definitely was not a whale and it was going to be some sort of fish.”



Mr Westfield now believes the remains to be of a basking shark, but he still can’t be sure.

He said: “We couldn’t say 100% because there are other species it could be, even including the whale shark – which is actually a bit bigger but then it could have been a juvenile.”

He continued: “We’ve taken pictures, we’ve taken a couple of samples, and we’ve sent them off to the Natural History Museum and some of the specialist teams there, along with London Zoo.

“We just have to wait and see what happens.”

As for what killed the sea beast, that will likely never be known.