Not only swimmers are at risk on Martha's Vineyard: Even at beaches where swimming is prohibited, like the secluded Cedar Tree Neck Sanctuary on the Island's northwest shore, the Portuguese Man o' War is still a safety hazard to barefoot walkers.
A sign at the sanctuary parking area Friday read:
A Portuguese Man o' War has washed up on the beach at Cedar Creek Neck Sanctuary, and these siphonophores have been found on many other island beaches. Do not touch them. The tentacles can still sting even if the animal is dead.
After several people suffered stings at South Beach Wednesday, the beach was closed till Thursday morning and is now open to swimmers at their own risk.
But as the warning at Cedar Tree Neck reminds us, the creatures can still sting while lying lifeless on the beach.
Often called jellyfish but actually a different type of organism, the Portuguese Man o'War transmits painful, sickening venom through its long, trailing tentacles.
According to a newspaper report, two people went to the hospital after being stung at South Beach Wednesday.
For first-aid tips and more information about these siphonophores, please see Stinging Sea Creatures Seen on Vineyard Sands: The Portuguese Man o' War is Back.
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