Toxic man o' war invasion: Stinging creatures cover South Carolina beach resort

Dozens of Portuguese man o' war have washed up on Hilton Head Island beaches this week but biologists are not sure why and why so many.

HILTON HEAD, SC – Watch where you step! Hilton Head lifeguards warned everyone heading to the beaches to beware of Portuguese man o' war because they are washing up in astounding numbers.

"We've seen dozens of Portuguese man o' war washed up on the beach today," Shore Beach Service posted on Facebook. "They are very colorful creatures, but do not touch them."

The post continued, "Their sting is extremely painful, and they will sting on the beach."

Why so many man o' war?

Lifeguards are unsure what brings this bumper crop of toxic creatures to South Carolina.

"It's kind of a mystery, but it happens every couple of years. We've seen more than usual. I think maybe in the summer we'll get five or ten overall," said lifeguard David Murphy. "But this is definitely a lot more than we're used to. This is definitely a unique event."

Marine biologists are equally perplexed at the recent influx of man o' war. 

"Usually we’ll see these or jellyfish show up in numbers when there have been strong storms offshore, but I don’t know of any recent offshore storms," said Daniel Sasson, Research Scientist with the Marine Resources Institute. "It also is less common to see them in large numbers in the winter, but certainly not unheard of." 


The species relies entirely on the wind and the currents, they can’t propel themselves. Strong onshore winds and storms like hurricanes blow the marine life onto the beach. The species are usually in groups, up to 1,000 or more, according to NOAA.

They prefer tropical and subtropical water but are found in nearly every ocean.

"Sometimes these blooms happen, but it’s not always easy to pinpoint the cause," said Sasson.


The South Carolina Department of Natural Resources get reports of the man o' war in the Grand Strand area, as well.

"It's not uncommon to see them on the beach in South Carolina in the winter, but it does look like a whole colony stranded on Hilton Head," said Erin Weeks of the Marine Resources Division. "Beautiful, interesting creatures that are fortunately easy to identify and avoid."

What is a Portuguese man o' war?

Regardless of the cause, the tentacled creatures will leave an impression if touched.

"The Portuguese man o' war is not going to kill you, but it's going to be painful, and it's going to be uncomfortable and very itchy for a while," said Tony McEwan, Curator and Marine Biologist at the University of Hawaii's Waikiki Aquarium, then added the toxin could be fatal to someone with an allergy. "Then it slowly, slowly dissipates."


The Portuguese man o' war, related to a jellyfish, fires barbs loaded with toxin when something brushes against its tentacles. The cells still fire even if the animal is dead and washed up on shore.

"These animals are some of the most toxic animals in the world," said McEwan. "They're not very maneuverable animals, so their prey has to be immobilized very quickly."

Tentacles trail from a bubble/float with a sail. The animal was so named because it looked like an 18th-century Portuguese warship under sail. 

The float can be a gossamer blue, pink or violet up to 6 inches long and sits 6 inches above the waterline. They look pretty but don’t touch.

The Hilton Head Shore Beach Service instructed lifeguards to gather as many as possible and bury them in the sand. Guards have not had any recent reports of stings.

"Luckily, it's a little too cold for people to go in the water, o not too many stings," said Murphy. "Not too much problem there."

What to do if you get stung

"The consensus is that the best way to treat it is doing a couple of things," said Sasson.

  • Spray or pour vinegar on the wound or where they stung you, which helps to deactivate the active firing cells.
  • Scrape the skin with a credit card. It removes stinging cells that haven't fired yet.
  • Soak affected skin in warm, almost hot water. The heat helps to destroy stinging cells that have not fired yet.
  • Try antihistamine for the itching.

Reports of men o' war are decreasing after a peak midweek, but still, keep an eye out and enjoy from a distance.