Beachgoers are being advised to watch where they step in Florida, Texas, and South Carolina.
Toxic Portuguese man o' war have reportedly been washing up on area beaches, posing danger to unsuspecting visitors.
These balloon-like sea creatures are typically blue, pink, or violet and are extremely toxic. Their tentacles—which can extend as long as 100 feet—are often poisonous even after their death.
"These animals are some of the most toxic animals in the world," Tony McEwan, Curator and Marine Biologist at the University of Hawaii's Waikiki Aquarium, told the New York Post. "They're not very maneuverable animals, so their prey has to be immobilized very quickly."
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Though they are often mischaracterized as jellyfish, Portuguese man o' war are siphonophores: colonial organisms consisting of numerous individual parts known as zooids. They feed by stinging and paralyzing small fishes with their long, venomous tentacles. Coming in contact with their tentacles can be extremely painful, and in rare cases, even cause death.
Be careful out there, y'all!