Warning as Portuguese man o’ war washed up on UK beach - what are they and are they dangerous?

Thursday, 17th September 2020, 11:11 am
Updated Thursday, 17th September 2020, 11:11 am
A potentially deadly sea creature has been spotted washed up on a UK beach (Photo: Shutterstock)

A warning has been issued after a Portuguese man o’ war was identified on a UK beach.

The creature, which looks similar to a jellyfish with long blue tentacles and a pink inflatable bladder which sits above the water, was found washed up on a beach in recent days in Wales and South West England.

While not native to British waters, the creatures are spotted on UK beaches from time to time, followed by warnings to the public not to touch them.

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This is due to their venomous sting, which in very rare cases can be fatal to humans.

What is a Portuguese man o’ war?

Though they might look similar to a jellyfish, the Portuguese man o’ war is in fact not a single living creature, but a colony of thousands of different organisms, known as polyps, which all perform different functions, working together to create what looks like a single animal.

Despite their appearance, the Portuguese man o’ war cannot actually swim, so they rely on the currents and wind to carry them along, and often end up clumped together in groups of 1,000 and more.

They drift through the oceans, their long dangling tentacles stinging and trapping often large fish, which are then digested over time.

The alien-like creatures take their name from where they were first spotted, and their supposed resemblance to a common type of ship at the time, the “Man of War”.

Are they dangerous?

Even when they are dead, often found washed up on beaches or rocks, their venomous stingers are still active and can stun or kill fish and small mammals.

While their stings are incredibly painful — as tens of thousands of people across the world find out every year — it is unlikely that one could kill a human.

Writing on Instagram, the Marine Conservation Society said they’ve had recent reports of the creatures washing up on beaches “in Wales and SW England”.

“These guys pack quite a sting,” they said, “so remember, look but don’t touch and if you spot any please report them to us for the National Jellyfish Survey”

Speaking to WalesOnline, marine biologist at Swansea University, Chris Lowe, said:

"I would strongly advise to not poke any that you find, and indeed to avoid walking barefoot nearby as their tentacles may fragment and bits be spread around the beach.

"Should you be stung by a Portuguese man o’ war it is going to hurt.

"Strong pain usually lasts for a few hours and you may end up with a red line where the tentacle touched you which may last for weeks."