The creatures can weigh up to five stone each (Picture SWNS) Huge jellyfish which weigh up to five stone each are swarming off British beaches – and no one knows why.

The creatures have tentacles up to six feet long, and are being left stranded on the island of Portland, Dorset, when the tide goes out.

Experts say the creatures have headed closer to shore because warmer seas have made more plankton available.

They have tentacles up to six feet long and are usually found in more tropical areas such as the Mediterranean sea.


Their sting isn’t considered dangerous, but can cause a nettle-like rash.



The creatures can weigh up to five stone each (Picture SWNS) Marine and wildlife photographer Steve Trewhella found 25 of the barrel jellyfish scattered across the 200 metre shore in just one day.

He says he thinks that ‘tens of thousands’ could be lurking in the deeper waters.

He said, ‘There are significantly more than last year. I am surprised they have hung around for two years.

Picture SWNS

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‘I have been going out for in excess of 30 years and before last year had not seen these since the 1980s.

‘I thought last year might have been a one off but a year later these giant jellyfish are back washing up on British beaches in bigger numbers than ever before.

‘Maybe this is what we have now, but if that is the case then something has changed. That is my concern and it should not be ignored.”