Swimmers warned after Portuguese man o’ wars wash up on south shore of Edgartown

Officials are warning the public to use caution if you’re swimming on the south shore of Edgartown after numerous reports of Portuguese man o’ wars washing up on the beach.

The man o’ war is a venomous predator, often mistaken for a jellyfish, that lurks up to six inches above the waterline on the beach, looking for small fish or crustaceans to feed on, according to the National Oceanic and Atmospheric Administration (NOAA). The animal is a species of siphonophore and may be blue, violet, or pink.

Their tentacles contain stinging nematocysts, which aren’t typically deadly to humans but cause extremely painful welts on exposed skin.

The Edgartown Parks Department says if you see the animal in the water, the best thing to alert a lifeguard or park patrol on South Beach or a Ranger if you’re on Norton Point.

“The tentacles contain stinging nematocysts, microscopic capsules loaded with coiled, barbed tubes that deliver venom capable of paralyzing and killing small fish and crustaceans. While the man o’ war’s sting is rarely deadly to people, it packs a painful punch and causes welts on exposed skin,” the Edgartown Parks Department wrote on Facebook.

No beaches have been closed yet due to their presence.

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