Hilton Head’s beaches are jellyfish graveyards once again. Here’s what to know
Springtime on Hilton Head Island means sheets of pollen and... jellyfish graveyards?
The island’s 12 miles of beaches have become dotted with dead jellyfish in recent weeks.
The phenomenon is natural and usually expected by locals, but the waves of dead animals on the shore are still off putting to beachgoers.
Here’s what to know about the jellyfish washing up on the beach:
What causes this?
Jellyfish travel in groups, called blooms, and sometimes rough winds, swells and currents send them to shore at once. Cooler water temperatures also contribute to mass jellyfish deaths.
“Jellyfish are organisms that swim with the current. They often get pushed to shore as a group,” Blaine Griffen, a marine biologist at the University of South Carolina, told The Island Packet in 2018. “Sometimes, it’s the current, and some of them are just killed by annual population cycles.”
April and May are “jellyfish bloom time in the North Atlantic,” the Marine Biology Association explained on Twitter in 2019. “If you’ve had onshore winds in the last few days, swarms of jellies can wash up.”
Jellyfish are mostly made of water, so they die quickly after washing onshore. They’re cold-blooded animals and can lose mobility when water temperatures are below normal.
This happens every year
Carlos Chacon, manager of natural history at the Coastal Discovery Museum, previously told The Island Packet that Hilton Head’s coast normally sees large numbers of jellyfish washing ashore during the spring and early summer.
The influx of dead jellyfish usually show up on the beach in mid-to-late April and last until early June.
However, weather-related incidents can happen at other times of the year that cause several hundred jellyfish to appear on shore at one time.
Cannonball jellyfish don’t sting
The good news is that the most popular jellyfish in South Carolina waters is the cannonball jelly, which does not sting.
In some countries, it’s common to see these types of jellyfish commercially harvested for human consumption. Cannonball jellyfish are high in protein and packed with nutrition.
Cannonball jellyfish look like mushrooms and lose their color soon after they wash up on shore.
... But others can
The bad news is that other dead jellyfish known to swim off the coast can sting you when they’re dead, like the Portuguese Man-Of-War, which is blue or purple in color and looks like a blown-up plastic bag.
The sea nettle jellyfish is responsible for the most stings on Hilton Head. Shore Beach Service lifeguards have recorded up to 600 jellyfish stings a day, mostly from sea nettles.
The best advice: Don’t touch a dead jellyfish if you don’t know what kind it is.
If the jellyfish has lost its typical round shape and is sort of flat, it is dead, Chacon said. However, if it is still round and freshly washed ashore, it might still be alive.
Nature takes care of these dead jellies
Don’t worry, no one has to clean up dead jelly bodies on the beach.
“They will get eaten by seagulls, crabs and other scavengers, and whatever is left of it will eventually decompose on the beach,” Chacon said.
Cannonball jellyfish are also a favorite food of the endangered leatherback sea turtles.
This story was originally published April 20, 2021 at 2:43 PM with the headline "Hilton Head’s beaches are jellyfish graveyards once again. Here’s what to know."
