Chris Garmston was walking his dogs on the beach near his home in Hilton Head Island's Port Royal Plantation Christmas morning when he spotted something unusual.
Electric blue and shaped like a giant dumpling, it lay motionless on the sand, looking similar to a piece of blown glass or a deflated balloon.
It was only after he'd returned to his house and researched his discovery that Garmston learned he'd almost stepped on one of the ocean's most dangerous predators: a Portuguese man-of-war.
He was walking the same beach Monday evening when he came across another, and then another. Garmston hadn't seen anything like it in his 14 years of living on the island.
"There were hundreds of them," he said. "It's the first time I'd ever seen the beach look like that."
The Portuguese man-of-war, also called the bluebottle for its appearance, uses long, thin tentacles to stun its prey. Its whip-like sting, which leaves a raised red welt, can hospitalize an adult.
And it's turned up with increasing frequency in recent weeks along Beaufort County's shores.
Participants in the Dec. 17 Fripp Island Audubon Club's bird count had to sidestep several Portuguese man-of-wars while scanning the horizon, and their presence has recently been reported on Hunting and Daufuskie islands as well.
Though they die soon after washing ashore, their venom remains potent for two or three days afterward, according to Al Stokes, manager of the Waddell Mariculture Center in Bluffton.
"You need to keep an eye open for them," Stokes said. "The stings can still put you in severe pain."
Despite their appearance, man-of-wars aren't jellyfish; they're siphonophores, incapable of independent survival in part because of the absence of any propelling mechanisms. They tend to congregate in groups of thousands, driven by currents and strong winds.
Stokes said that stronger-than-usual winds from the south, propelling the animals up the Gulf Stream, probably are responsible for this year's bumper crop of bluebottles.
Their presence could jeopardize the sixth annual Hilton Head Polar Bear Plunge, scheduled for 11 a.m. Sunday at Coligny Beach.
"I want people to have a good time," plunge organizer Tim Guest said. "I don't know what to do right now."
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