Caution: Portuguese Men O’War Have Reached New England Waters

Sometimes a day at the beach can burn, especially if you cross paths with the venom-filled Portuguese man o’ war.

Last week, men o’ war sightings were reported off the coast of Martha’s Vineyard, and now, they are beginning to pop up in Rhode Island waters.

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On Tuesday, The Rhode Island Department of Environmental Management informed residents that the jellyfish-like creatures were spotted at Scarborough, Roger Wheeler, and East Matunuck State Beaches this week, leading DEM to fly purple flags to warn of dangerous marine life.

So, what does this mean and are they harmful to humans? What do you do if you find yourself swimming by one? Here are some helpful tips to abide by this summer.

What is a Portuguese Man O'War?

It is often called a jellyfish, but according to the National Ocean Service, it is actually a species of siphonophore, a group of animals that are closely related to jellyfish.

“Found mostly in tropical and subtropical seas, men o’ war are propelled by winds and ocean currents alone, and sometimes float in legions of 1,000 or more,” explained National Ocean Service.

Men o’ war were named after its resemblance to an 18th-century Portuguese warship under full sail and it’s most likely recognized by its balloon-like body, its blue, violet, or pink color, and its strands of tentacles and polyps floating below the water’s surface, which grow to about 30 feet and can extend by as much as 100 feet.

Are Portuguese Men O’War Deadly to Humans?

The tentacles of a Man o’war contain stinging nematocysts, microscopic capsules with barbed tubes that deliver a venomous sting.

While its venom is capable of paralyzing and killing small fish and crustaceans, it is rarely deadly to people. However, it will pack a painful sting and can cause welts on the skin. It can even sting after being washed ashore for weeks.

An experience with a Man o’war is less than desirable, but as long as you swim with caution and avoid contact, these pesky sea creatures will soon float their way back down the Gulf Stream.