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Have you spotted any jellyfish on UK shores?

A mass of jellyfish are on a sandy beach beside a wall with the headland in the distance.Image source, Bude Sea Pool
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A huge bloom of jellyfish was brought in on the tide at Bude

During the summer holidays, some of you may have spent some time at the seaside and even dipped your toes in the water.

It's important to follow water safety advice, but you may also need to be cautious about an increase in jellyfish across UK coastlines.

In recent years, there have been reports of high numbers of jellyfish blooms from Cornwall to South Wales, and up to Scotland.

So what is causing this surge in numbers of the strange looking sea creatures?

A moon jellyfish with its four pink rings, washed up on a UK beach Image source, Getty Images
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You'll often find moon jellyfish washed up on beaches, like this one spotted in North Devon. They are generally harmless.

Jellyfish are brainless creatures. They also have no heart.

But they do have long tentacles and sometimes those long stringy tails can pack a punch.

The jellyfish that tend to be found in the UK waters are not very harmful, unlike those found in warmer waters like in Australia.

But they will still sting and some species cause a red bumpy rash which will itch and cause irritation on your skin.

So why are there more of them around the UK these days?

There are a number of reasons.

An upright compass jellyfish, with it's distinctive brown markings down the 'bell' of the jellyfish.Image source, Getty Images
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Compass jellyfish are named after their compass-like appearance, but be careful - they pack a nasty sting!

Warmer seas due to hotter weather means jellyfish grow and reproduce a lot faster than in cooler waters.

Their main food source, plankton, also breed faster in warm seas, which can bring large groups (or blooms) of jellyfish to those areas.

Strong favourable currents also keep jellyfish in certain places rather than dispersing them across wider areas.

Plus a reduced number of predators such as leatherback sea turtles, sunfish and some seabirds, can also mean jellyfish lifespans last longer.

Let us know in the comments if you have ever seen a jellyfish in UK waters.

But experts say if you see a jellyfish, it's best to leave it alone and don't touch it just in case!