PROVIDENCE – After a Portuguese Man o’ War discovered at Scarborough State Beach closed the area to swimming at 5 p.m. Sept. 7, the Department of Environmental Management announced it will fly purple flags warning swimmers of the creatures and their painful sting when they’re found at state beaches.
A purple flag means that swimmers should swim at their own risk.
DEM beach managers closed the beach after two swimmers reported being stung by something. Beach staff retrieved a Portuguese Man o’ War from the water and identified it, according to the DEM. The presence of the stinging animals is recent, according to the DEM. The agency’s Division of Marine Fisheries conducted a survey of coastal waters during the last week of August but did not see or find any man o’ war.
Portuguese Man o’ War: Animal Colony, Sting with 30-ft reach
Referred to as a jellyfish, the Portuguese Man o’ War actually is a siphonophore, a colony of different organisms working together as one, according to a DEM announcement on the finding. The predatory colony uses feeding tentacles to sting and paralyze small fishes, crustaceans, and other invertebrates.
DEM is cautioning swimmers to swim at their own risk and be vigilant. The tentacles of the man o’ war can grow to 30 feet and longer. They “contain stinging nematocysts, microscopic capsules loaded with coiled, barbed tubes that deliver venom capable of paralyzing and killing small fish and crustaceans,” according to the National Oceanic and Atmospheric Administration.
“If swimmers see something that looks like a balloon floating on top of the water, they should stay far away,” said McNamee. “Once the man o’ war gets into the surf zone, if the water is rough, the tentacles can break apart and they can continue to sting even while unattached. The sting is very painful and can leave scars on people with more sensitive skin.”
Warm waters bring Portuguese Man o’ War
“What often is the case at this time of year is that a warm core ring has peeled off from the Gulf Stream and come close to the Rhode Island coast,” said Jason McNamee, DEM Deputy Director for Natural Resources and a marine biologist. “It likely has brought in a slug of warm water that can contain all manner of interesting creatures. These marine events are usually short-lived.”
Typically, the prevailing summer wind is from the southwest, but over the weekend it often was blowing in from the southeast – which is directly onshore at Scarborough and could also explain the dead Minke whale that came in with the tide Sept. 6.
First Aid for Portuguese Man o’ War Stings
A Portuguese Man o’ War sting should be treated by carefully remove remaining tentacles with fine tweezers or with a gloved hand (a plastic bag works in a pinch) and rinsing the affected area with white vinegar to prevent any remaining stinging cells from firing. Then, soak the skin in hot but not scalding water (110 – 113F) or take a hot shower for at least 20 minutes. The heat will denature the protein in the venom. If symptoms do not go away or pain gets worse, contact a doctor.