ISLE OF PALMS -- A teenage tourist apparently was bitten by a shark, and dozens more beachgoers were stung by jellyfish this past weekend.

Isle of Palms Fire Chief Ann Graham said the teenage boy was standing in about 4 feet of water Sunday, throwing a football with a group of friends, when he felt a bite to his lower leg.

The teen saw what appeared to be a shark and yelled for everyone to get out of the water as he ran toward the beach, Graham said.

The boy was treated at the beach and taken to a local hospital.

"It was pretty significant," Graham said. The beach was not cleared after the bite. Graham said rescue workers clear the ocean if more than one shark appears to be present and there's concern for bathers' safety. "This was a bite. It wasn't an attack. People need to understand there are all kinds of marine life in the water at any given time."

Graham said the bite occurred on the same weekend in which they responded to about 50 jellyfish sting calls. They responded to about 30 calls Saturday, 20 on Sunday and about five so far Monday. Jellyfish stings also were reported at Folly Beach among other sites.

The teenager was at least the fourth person to apparently be bitten by a shark so far this summer along the South Carolina coast. The coast tends to see three to five bites per year, said Mel Bell, S.C. Natural Resources Department fisheries management director, and this bite was typical.

"It's a relatively small animal. They hit usually a leg or an ankle and release," he said. Bathers should retreat when they find themselves in among baitfish, jumping fish or birds feeding on fish. That's food for the shark too. "Sharks are with us. They're out there. Use your head. Be aware of your surroundings," he said.

The last fatal bite in South Carolina was more than a century ago, and that one might not have been fatal if emergency help had been nearby, Bell said.

"Shark bites are simply not something that we need to be worried about. It's also important to keep in mind that sharks serve a vital role in the marine ecosystem, and their populations are declining at alarming rates around the world," David Shipman, a marine biology master's student at College of Charleston, who studies shark feeding, ecology and conservation. "Despite the occasional bite, humans are a lot better off with sharks than we are without sharks."

Jellyfish are common at the beach year round but had been relatively unobtrusive until this weekend. They occasionally show up in swarms.

The jellyfish this past weekend likely blew in with onshore winds and the roiling surf made them tough to see, said Bob Van Doolah, DNR Marine Resources Research Institute director. They might have been sea wasps, which tend to be smaller and lose tentacles in rough water. Tentacles can still sting after they are torn from the jellyfish. "It's anybody's guess" when the jellyfish will move on; it depends on current and winds, he said.

Normally, responders will put an alcohol and baking soda mix on the stings and allow the person to be on their way. In the rare occasion that someone goes into shock, they are taken to the hospital, she said.

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