Portuguese Man O War – Advice

Throughout the summer and autumn it is not uncommon to see Moon Jellyfish, Compass Jellyfish or Blue Jellyfish stranded on the shoreline. Sometimes more rare creatures such as By The Wind Sailors and Portuguese Man O War can be found.

What are they?

The Portuguese Man O War, also known as the blue bottle, are not jellyfish but a siphonophore. Whereas a jellyfish is a single organism a siphonophore is a colonial organism formed of lots of specialised animals (polyps) that work together to function like an individual animal. The colony of polyps that form a Portuguese Man O War provide a range of special functions that help ensure they all collectively survive and flourish.

The Portuguese Man O War remains on the surface of the ocean thanks to its gas filled bladder. This bladder is easy to identify thanks to its translucent blue, purple and/or pink colour. The shape of the bladder resembles a bottle, which is why it’s called a bluebottle in Australia, but with its crimped edge it also resembles the shape of a Cornish pasty. Its fine tentacles remain submerged under the water for the purpose of catching fish and other small animals.

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Why are we finding them on North Devon beaches?

The Portuguese Man O War has no means of moving itself around, their movement and migration is determined by the wind, tides and ocean currents.

The gas bladder found at the top of the Portuguese Man O War not only keeps it afloat but also acts as a sail. If one happens to be floating near land strong onshore winds can drive them onto the coastline, where waves and tides can result in them becoming stranded on the shore and sometimes in large numbers.

Although they are rare visitors to the North Devon coastline it is natural to find these marine creatures on the coastline and if treated with care and respect they are unlikely to cause any injury.

What do I do if I get stung by one?

The sting from a Portuguese Man O War can initially cause severe pain. This pain should naturally lessen after a couple of hours but the affected area will remain painful. The affected area will also show whip-like red marks.

The stings associated with most jellyfish are not very serious and no worse than a nettle sting. The Portuguese Man O War has developed quite a reputation as having a dangerous sting and although it can cause severe pain it is rarely fatal. The tentacle of a Man O War houses millions of stinging cells, which automatically release toxins when it comes into contact with an object. The stinging cells of the tentacle still function when separated from the main body of the creature or when it becomes stranded on the shoreline.

  • If you come across a Portuguese Man O War, or any other jellyfish, stranded on the beach it is advisable not to touch it.
  • If you are stung it is recommended that you first wash the affected area with salt water and not fresh water. This will help wash out any stinging cells that may still be on the skin. Freshwater could result in more toxin being discharged prior to the cells being washed away.
  • If you wipe the affected area whilst washing it with salt water be aware that the item used may also collect stinging cells. Please ensure it is thoroughly rinsed prior to using it again.
  • After a salt water wash the affected area can be soaked in hot water. The heat will help breakdown the toxins.
  • Painkillers can be used to provide pain relief.
  • The pain from a sting lasts a few hours. If there is severe or lasting pain, or the area becomes infected it is important to seek further medical help.

For further advice on the treatment of stings please refer to the NHS website.

What do I do if my dog gets stung?

Jellyfish can pose a serious threat to dogs, even if they are washed up dead on the beach.

According to animal website Vets Now, there are 9 signs of jellyfish stings in dogs

  • Vomiting
  • Excessive drooling
  • Swelling
  • Retching
  • Licking affected area
  • Difficulty breathing
  • Quiet and lethargic
  • Itching
  • Pain

Laura Playforth, Vets Now’s head of veterinary standards, said dogs stung by jellyfish should be seen by a vet as quickly as possible.

She said: “If your dog is stung by a jellyfish pull the remaining tentacles off with a stick or towel but never rub them and be careful not to touch them with your hands.

“Never rub the injured area on your dog with sand and always clean it with sea water rather than fresh water.

“If you suspect your dog has been stung you should contact your vet or emergency pet clinic straight away.”

Man O war

Should I report it?

Reports of sightings can be logged on the Marine Conservation Society website. You can also leave a comment of your sightings on this page or on the Ilfracombe Town Council Facebook page.

References and content based on  original publications by Cornwall.gov.uk and Devon Live

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