(WVUE) - Those planning on hitting the beach this weekend may want to keep an eye out for those purple flags in the water. Lifeguards at Pensacola Beach posted them to warn beach-goers of tiny jellyfish called 'Sea Lice.'
"Every year around this time, the jellyfish reproduce, and it produces a cloud of baby jellyfish," Senior Curator of Husbandry at Audubon Aquarium, James Arnold said.
"This time of the year, there's always jellyfish in the waters because jellyfish don't swim very well, and so they get caught up in the currents and that's how they get in closer to the beaches," Loyola Biology Professor Amee Thomas said.
Experts say you can expect them to be out by beaches during the spring to summer months.
"Generally, they exist from March to June in warm waters from around the Florida and into the Caribbean area," Dermatologist Kyle Coleman said.
Unlike adult jellyfish, sea lice don't attack exposed areas.
"Inside clothing like waistbands and bathing suits, they get stuck there, and that irritation causes them to release their toxin," Coleman said.
"These sea lice are the actual larval stage of the jellies, and so if they get in between your bathing suit and your skin, they'll irritate and they'll rub and cause an irritation to your skin, and some people react worse than others," Thomas said.
They're also difficult to avoid.
"They're microscopic, and they're transparent, so you can't see them in the water, but they look like a small disc, and they do have the stinging cells, and small tentacles like the adults do, so they can still sting," Arnold said.
Coleman says sometimes, people don't feel the effects until hours after being stung
"The most important thing is getting out of your swim clothes, out of a wetsuit, out of the swimsuits and washing off with fresh water. If you're really prone to aggravation, even vinegar can sometimes make it less likely to get irritation," Coleman said.
He says symptoms vary - rashes can last from a few days to almost two weeks. But just like bug bites, they're nothing more than pests.
"If you have a healthy immune system, play and have fun. And just be aware that there are organisms in the water that can sting you, but still enjoy the beach," Thomas said.