Portuguese Man O’ War Warning: What Tourists Need to Know Before Swimming in France and Spain

Portuguese man o’ war sightings are increasing along parts of the French and Spanish Atlantic coast. Learn how to identify them, avoid stings and respond safely after contact.

Tourists warned as Portuguese man o’ war sightings increase

Holidaymakers heading to beaches along the Atlantic coast of France and northern Spain are being urged to take extra care following reports of increased sightings of Portuguese man o’ war.

The marine creatures, which are often confused with jellyfish, have been reported in areas including France’s Pyrénées-Atlantiques department and around San Sebastian in Spain. Local authorities have introduced warnings and beach-management measures to help protect swimmers.

Although these creatures can be striking to look at, their tentacles can deliver a painful sting. Even more importantly for beach visitors, the tentacles may remain capable of stinging after the animal has washed ashore or died.

For anyone planning a summer beach holiday in the region, understanding what a Portuguese man o’ war looks like and knowing what to do after contact can help prevent an otherwise enjoyable day from turning into a medical emergency.

Where have Portuguese man o’ war been spotted?

Reports have emerged from parts of France’s Atlantic coastline, particularly in the Pyrénées-Atlantiques area.

Further south, authorities in San Sebastian have also warned beach users about the presence of the creatures. The Spanish city has been using its beach flag system to communicate changing conditions to swimmers.

Beach conditions can change during the day depending on how many Portuguese man o’ war are found and the size of the specimens. As a result, tourists should pay close attention to signs, flags and instructions from lifeguards before entering the water.

Some beaches may temporarily restrict swimming when the creatures are present in significant numbers.

What is a Portuguese man o’ war?

Despite commonly being described as a jellyfish, the Portuguese man o’ war is not actually a jellyfish.

Its scientific name is Physalia physalis, and it is a colonial hydrozoan. This means that what appears to be one animal is actually a colony of specialised organisms known as zooids. These organisms perform different functions while working together as a single living unit.

The creature is particularly recognisable because of its floating structure. It can have a translucent, purple or pinkish-blue appearance, while long tentacles trail underneath the surface.

The float can sometimes be spotted bobbing on the water. However, identifying one may become more difficult after it washes onto a beach, because its colour can fade and the body may become much less noticeable.

This makes it important never to assume that a washed-up specimen is harmless.

Why can a Portuguese man o’ war sting be dangerous?

The main concern is the creature’s tentacles.

They contain specialised cells that can release venom when triggered. Contact can cause an intense, painful reaction to the skin, with symptoms potentially including burning, irritation and visible marks.

One of the biggest safety concerns for beachgoers is that the tentacles can remain capable of stinging even when detached from the main body.

That means tourists should never touch a Portuguese man o’ war found on the sand, even if it appears dead.

Parents should also make sure children understand that these colourful marine creatures are not something to pick up or play with.

What should you do if you are stung?

If you believe you have come into contact with a Portuguese man o’ war, the safest approach is to leave the water and seek assistance from a lifeguard or local medical professional.

French authorities have advised people dealing with a suspected sting to rinse the affected area with seawater and avoid rubbing or scratching the skin.

Importantly, they advise against using fresh water on the affected area, as this can potentially trigger further discharge from remaining stinging cells.

The Pyrénées-Atlantiques authorities have also provided specific guidance involving a mixture of food vinegar and seawater in certain circumstances. However, first-aid recommendations can vary depending on local health guidance, so visitors should follow the instructions provided by lifeguards and medical professionals in the area.

If pain continues or symptoms appear severe, medical attention should be sought promptly.

Beach flags can provide an important warning

One of the simplest ways tourists can reduce their risk is by paying attention to local beach-warning systems.

In San Sebastian, authorities have been using a specific flag system to alert swimmers to the presence of Portuguese man o’ war. A white flag can indicate that the creatures have been detected, while a red flag can prohibit swimming.

Visitors should therefore check the flags before entering the sea and continue monitoring them throughout the day.

It is also worth remembering that conditions can change quickly. A beach that appears safe in the morning may have different conditions later, particularly when marine creatures are being carried towards the shore by tides and currents.

What should tourists do before swimming?

A few simple precautions can make a beach visit safer.

First, check local warnings before entering the water. Lifeguard stations and beach entrances may display posters or information about Portuguese man o’ war, jellyfish and other marine hazards.

Second, look carefully at the shoreline and water before swimming. If you see unusual floating objects or translucent creatures with purple, pink or blue colouring, keep your distance.

Third, never touch marine animals that have washed ashore.

Finally, if lifeguards advise against swimming, follow their instructions. Beach closures and warnings are designed to reduce the risk to visitors and can change according to local conditions.

Other marine hazards along France’s Atlantic coast

Portuguese man o’ war are not the only marine animals that can cause problems for swimmers.

Health authorities in southwestern France have also highlighted other potentially hazardous marine species, including certain jellyfish and weever fish.

This is why visitors should familiarise themselves with local beach information rather than assuming that a particular stretch of coastline is completely risk-free.

Many French beaches provide information boards near entrances, giving visitors guidance about marine wildlife and appropriate first-aid measures.

For international tourists, asking a lifeguard for advice can also be useful, particularly if warnings are displayed in a language they do not understand.

The key message for beachgoers

The appearance of Portuguese man o’ war along popular Atlantic beaches does not mean tourists need to cancel their holidays.

Instead, visitors should treat the warnings seriously, stay informed and avoid entering the water when local authorities or lifeguards advise against it.

The most important rule is simple: do not touch a Portuguese man o’ war, whether it is floating in the sea or lying on the beach.

By checking beach flags, following lifeguard instructions and knowing what to do after a suspected sting, holidaymakers can enjoy France and Spain’s Atlantic coastline while taking sensible precautions.

Source

The Independent on 11 August 2026.

Disclaimer

This article is intended for general travel-information purposes only and should not be considered medical advice. First-aid recommendations may differ according to local health guidance and individual circumstances. If you experience a severe reaction, persistent or worsening pain, breathing difficulties, or other concerning symptoms following contact with a marine animal, seek urgent medical assistance and follow instructions from local emergency or healthcare professionals.