Wildlife experts have warned beachgoers to steer clear of a potentially deadly creature that has started to wash up along the UK coastline.
The Portuguese man o’war can grow tentacles up to 160 ft (49 metres) long and their sting can be extremely painful – and can even kill a person.
Stormy weather has washed up the predators – which are often mistaken for jellyfish – onto Sennen Beach and Portheras Cove in Cornwall, from their natural home on the surface of the open ocean.
They prey on small fish and crustaceans and their sting can cause severe pain to humans, which usually subsides after three hours.
However, the venom can travel to the lymph nodes, causing breathing difficulties, fever and shock – and in rare cases, death,
The tentacles of the Portuguese man o'war, which is also nicknamed the Floating Terror, are usually around 30 ft, but can grow to up to 160 ft long.
While the creatures may die after being washed up, their tentacles still have the ability to sting and sightings of them can cause beaches to close as a precaution.
A spokesman from the Wildlife Trusts told Cornwall Live: “They can’t swim and are at the mercy of the winds — which is why they often end up washed ashore after big storms.
“They are fearsome predators, catching small fish and crustaceans with their long stinging tentacles.
"It’s these tentacles that you need to watch out for too — they can sting long after the animal has died.”
The Friends of Portheras Cove posted a warning on their Facebook page that urged visitors to “admire from a distance” but “do not touch”.
They added: “Take extra care if you are paddling, swimming, or boarding on the north coast beaches…
“If you are stung please seek medical advice and do not resort to any old wives/old fishermen's/old beachcombers tales… they do not work with these creatures.”
While often mistaken for jellyfish, the Portuguese man o’war is a colonial hydrozoan, made up of small individual animals called zooids which can’t live separately.
They are unable to swim, meaning stormy weather in the autumn months often means they end up on the beaches of Britain.
Despite their deadly reputation, the odds of being killed by a Portuguese man o’war are slim – the most recent notable case was in 2010 when swimmer Maria Furcas, 69, suffered a fatal allergic reaction to being stung near Cagliari, Sardinia.
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