Picture this: It’s a warm spring or summer’s day in Hilton Head. You wade into the Atlantic, the water warm and welcoming, and you notice something floating beside you. Then another. And another.

Blobs in the surf. Strange translucent forms strewn across the sand like spilled Jell-O. Yes, we’re talking about jellyfish.

Before you squeal or steer clear, hear this: these sea creatures are a natural part of Hilton Head’s marine beauty. They’re fascinating once you get to know them!

Jellyfish Quick Facts

Despite the name, jellyfish aren’t fish at all. Marine biologists call them “jellies” because these graceful drifters lack bones, brains, and backbones, things real fish typically have. These gelatinous invertebrates are mostly made of water and rely on ocean currents, tides, and winds to get around.

No, jellyfish don’t sting humans on purpose. If you get zapped, it’s because you bumped into one and they fired stinging cells reflexively.

Types of Jellies in Hilton Head

Hilton Head’s coastal waters are home to a variety of jellyfish. Some are small and harmless. Others? Not so much. Let’s meet the main jellyfish species you’ll encounter on the island.

Cannonball Jellyfish

The cannonball jellyfish (or “cabbagehead” jelly) is the most common jelly bobbing in Hilton Head’s waters. Scientifically named Stomolophus meleagris (which translates to “many-mouthed hunter”), this jelly has a thick, rounded bell that can be milky blue, yellow, or brown. It looks like a gelatinous mushroom cap on the move!

Cannonball jellies have 16 short, fused oral arms for catching prey. They’re surprisingly strong swimmers, zipping along in a horizontal direction and even performing acrobatic flips when threatened. They also secrete a toxic mucus.

When cannonball jellies wash up on the beach, they become a buffet for crabs, birds, and leatherback turtles.

Moon Jellyfish

The moon jelly (Aurelia aurita) is the ballerina of the sea. They have a distinctive saucer-like bell with four horseshoe-shaped gonads visible through the top. Their delicate, short tentacles trail gently from the bell’s edge and pulse through the water like ghostly lanterns.

These jellies are carnivores. Their sting is mild and usually harmless to humans, though sensitive skin might react with a little rash.

Moon jellies often gather in massive blooms when conditions are right. They’re mesmerizing to watch and make for great ocean photography if you’re into that.

Lion’s Mane Jellyfish

Now, this one’s a showstopper. The lion’s mane jelly (Cyanea capillata) is one of the largest jellyfish in the world. On average, they reach about 1.5 feet across, but some giants have tentacles that stretch over 100 feet. That’s longer than a blue whale!

Their bell is thick in the middle and fringed with hundreds of thread-like tentacles arranged in eight clusters. They create living nets to trap fish and crustaceans, stunning them with powerful stings. And yes, those stings can be painful to humans.

Lion’s manes come in dark yellows and reds, and they can even glow in the dark thanks to bioluminescence. Beautiful? Absolutely. Handle with care? You bet.

Sea Wasp (Box Jellyfish)

Let’s be honest: the sea wasp is the stuff of jellyfish legends. Also known as the box jellyfish (Chironex fleckeri), this cube-shaped creature is pale blue and nearly invisible in water. Unfortunately, it’s also extremely venomous.

Each corner of its boxy bell supports a cluster of long, trailing tentacles, and it’s capable of fast movement, shooting through the water at up to four knots. The box jelly uses its venom-packed tentacles to paralyze prey like small fish and crustaceans.

While sightings of the sea wasp near Hilton Head are rare, caution is always wise.

Sea Nettle

The Atlantic sea nettle (Chrysaora quinquecirrha) is a stinger with style. It has a bell-shaped body, scalloped edges, and long, lacy oral arms that trail dramatically beneath it. You’ll notice long tentacles that zap unsuspecting prey (and sometimes humans).

Colors vary from pink and maroon to golden-yellow, depending on where they live. Some have stripes radiating from their bells, while others are more translucent.

Sea nettles aren’t aggressive, but their sting can be irritating, like a mild sunburn or brush with a nettle plant (hence the name). If you see one, admire it from a distance and keep swimming.

Bonus: Portuguese Man o’ War

The Portuguese Man o’ War (Physalia physalis), often mistaken for a jellyfish because they look like one, is actually a siphonophore. This striking creature floats on the ocean surface with a gas-filled bladder while its long, venomous tentacles dangle below. Some specialized creatures like loggerhead sea turtles and ocean sunfish are immune to its venom and feed on it.

Warning: Even when washed ashore and seemingly lifeless, Portuguese Man o’ War can still deliver a painful sting. Avoid touching them under any circumstances!

Signs You’ve Been Stung by a Jellyfish

Jellyfish stings can happen quickly. While the severity of the reaction depends on the type of jellyfish and individual sensitivity, several common symptoms indicate you’ve been stung.

• A sudden stinging or burning sensation on the skin
• Red, brown, or purple tracks where the tentacles made contact
• Swelling or raised welts at the sting site
• Tingling, itching, or numbness around the affected area
• Throbbing or shooting pain
• Nausea or dizziness (in more severe cases)
• Difficulty breathing or chest tightness (possible sign of a severe allergic reaction)

What To Do If You Get Stung

So, what happens if a jelly decides to say “hello”? First, don’t panic. Next, get out of the water to do the following:

• Rinse with vinegar to neutralize the venom and prevent more stingers from firing.
• Remove tentacle bits using tweezers (not your fingers!).
• Soak in hot water to ease the pain.
• Get medical attention ASAP if you have trouble breathing, swelling, or severe pain.

What NOT To Do After Getting Stung

Some common remedies and reactions can actually make the sting worse. Avoid the following mistakes:

• Scraping out stingers
• Rubbing with a towel
• Rinsing with human urine or cold, fresh water
• Applying meat tenderizer, alcohol, ethanol, or ammonia
• Applying pressure bandages

Learn More About Hilton Head’s Jellies

Hilton Head’s jellyfish may be weird, wiggly, and sometimes stingy, but they’re vital to the ocean ecosystem. Take a moment to appreciate these ancient, graceful creatures!

At Beachside Hilton Head, we want your island getaway to be as memorable and comfortable as possible. Our vacation rentals place you steps away from the shoreline, with the chance to witness marine life up close. From a safe and respectful distance, of course.

Contact Beachside Hilton Head online or call (843) 342-9909 to book your stay!