Invasion of the blue jellyfish: Warning over 'sea nettle' stingers

These astonishing pictures show the latest jellyfish menacing British beaches in record numbers - a potent, bright blue stinger known as the 'sea nettle'.

The tentacled invaders have previously visited British shores but experts fear our warming seas could attract millions this summer.

Surfing photographer Paul Terry sounded the alarm after spotting hundreds of the umbrella shaped blobs lurking yards from swimmers in Newquay, Cornwall.

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Blue jellyfish - or Cyanea lamarckii - grow up to 12in (30cm) in diameter, and have a distinctive bright blue bell, as well as purple lines running down their insides.

They can deliver a painful sting, similar to that of a nettle, and can even trigger anaphylactic shock in people who are allergic.

Paul, 36, said: 'There were hundreds of them floating straight for the shore. I've never seen so many.

'The wind was blowing them right up to the beach where people were swimming and enjoying the weather.

'The tentacles are about a metre long and if you get one wrapped around your ankle it can be really painful.

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'They float just beneath the surface so there's a chance you could swim face first into one or get a tentacle in your eye - it could be pretty dangerous.'

Experts say jellyfish are thriving in our waters, with more and more flutters reaching our beaches over the past few years.

The biggest new arrivals are dustbin-lid shaped barrel jellyfish, which have spooked British bathers because of their massive size and strange appearance.

But the 3ft wide creatures don't actually pack a proper sting - unlike their smaller, more potent blue jellyfish cousins.

Sea nettles mainly feed on plankton, but will eat anything that sticks to their long tentacles - including other jellyfish.

The species will eventually die out in Autumn, once the plankton supply falls and the seas become rougher.

Paul added: 'They may be frightening for swimmers but they are beautiful to look at.

'They are complex and fascinating - but they turn to mush.'