Brits warned over rising number of venomous Portuguese man o’ war sea creature after hundreds are spotted around the UK

BRITS have been warned of an invasion of Portuguese man o’ war, as the venomous jellyfish-like sea creatures descend on UK shores.

There were 280 sightings of the creature, also known as bluebottles, in the year to September 2024, according to the Marine Conservation Society.

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That is a 16 per cent increase compared to the year before.

These creatures have not been common in UK and Irish waters historically, according to Calum Duncan, policy and advocacy chief at the Marine Conservation Society.

He added: “The rise in Portuguese man o’ war sightings in October may be attributed to strong westerly winds bringing them to our shores.”

Portuguese man o’ war are typically found in warm, tropical and subtropical waters.

Although closely related to jellyfish, these creatures are actually a species of siphonophore – a colony of different organisms that all depend on each other.

The alien-like creature has a large purple body, with the ripped crest tipped with pink and long blue-purple tentacles.

They quickly lose their colour after stranding, as shown in the video above, and can appear translucent with just a tinge of purple.

While they are fascinating, and may be tempting to poke at, experts have urged beachgoers to steer clear.

“The tentacles contain stinging nematocysts, microscopic capsules loaded with coiled, barbed tubes that deliver venom capable of paralysing and killing small fish and crustaceans,” the National Ocean Service explained.

“While the man o’ war’s sting is rarely deadly to people, it packs a painful punch and causes welts on exposed skin.”

The tentacles can sting long after the animal has died.

While they are deadly to other sea creatures, they are rarely lethal to people.

They can, however, cause severe pain if touched and can cause welts on exposed skin and painful scars.

Hundreds of man o’ war washed up in Cornwall in November 2020, an influx which was again explained by windy weather at the time.

One woman said she was stung on her nose by a long tentacle and feared her “nose was going to fall off”.

What is Portuguese Man o’ War and why are they so dangerous?

The man o’war is not a true jellyfish but a colony made up of small individual animals called polyps that are unable to survive alone.

Portuguese man o’ war – also known as the floating terror – have an extremely powerful sting that on rare occasions can kill.

The sea creatures (Physalia physalis) are not true jellyfish but siphonophores.

These are colonies of hydrozoans – lots of tiny marine organisms living together and behaving collectively as one animal.

They get their name from the balloon-like “sail” that floats above the water, which was said to resemble a type of 18th century warship.

Unable to move independently, the creature floats on the surface and is propelled by a balloon-like ‘sail.’

Its tentacles can be more than 30 metres long and they deliver a painful sting causing whip-like red welts on human skin.

Stings are not usually fatal but can provoke an allergic-type reaction in some cases, while urgent medical attention might be needed if a person comes into contact with many tentacles.

Instances where a tentacle becomes wrapped around the victim’s torso are said to cause the most deaths, especially in children.

The polyps can detach from the body of the man o’war and float for several days while remaining venomous.

Brushing against one can lead to an agonising and potentially lethal sting.

A stranded Portuguese man o’ war looks a bit like a deflating purple balloon about the size of a Cornish pasty with blue ribbons attached.

They drift on the ocean currents and every year they wash up in their thousands on beaches from Britain to Australia.

Stormy weather doesn’t just invite these purple terrors, but turtles too.

This past year, the Marine Conservation Society recorded three dead Kemp’s ridley turtles and two dead loggerhead turtles on UK beaches, during the winter months.

There was also one other turtle unable to be identified.

Kemp’s ridley turtles are the rarest and most threatened species of marine turtle, according to the charity.

They are currently listed as critically endangered, but are enjoying a steady comeback thanks to strict laws to protect their nesting beaches in Mexico.

Their numbers have blossomed from a low of 200 in the 1980s, to between 7,000 and 9,000 today.

But experts believe these turtles – which are usually quite young when they wash up – are dragged to the UK by strong winds and currents.

They are not suited to the UK and Ireland’s cold waters, but their frequency can be an indication of stormy weather, the charity explained.