JENSEN BEACH, Fla. (WSVN) — People at some Florida beaches are on the lookout and watching their steps for blue sea creatures that have been washing ashore along the Treasure Coast, and their sting can pack a major punch. Portuguese man o’ war have been spotted all over the shoreline at Jensen Beach this weekend. “Like, they look like bubbles,” said a beachgoer. “They immediately made me think about the cartoon SpongeBob,” said another beachgoer. Man o’ war are closely related to jellyfish. A Tennessee resident said she saw one for the first time. “I’d never seen one before, so I thought it was super fascinating,” she said. Fascinating for some, but dread-inducing for others. “I’m a little frightened by it,” said a beachgoer. For this beachgoer, they’re an aching memory after, she said, she was stung a few years ago. “Worse than a bee sting. Worse, much worse,” she said. These sea creatures serve as a painful reminder for beachgoers to watch where they swim and step. “I came out here with bare feet, and I’m going back to get my shoes,” said the beachgoer who had been stung. Man o’ war can sting even weeks after washing ashore. Martin County Ocean Rescue Lt. Chris Dunn said this is the season for residents to be on the lookout for man o’ war. “It has to do with the stronger winter storms that we get, and so, it blows them out of the Gulf Stream and onto the shore,” he said. Dunn said the best way for beachgoers to avoid being stung is for them to be aware of their surroundings. “They’re real distinctive. You can see them, and so, just keep your eyes peeled, and you can avoid being stung by them just by simply looking,” he said. The stings can also cause welts on exposed skin. One way to tell whether there are man o’ war nearby is if lifeguards have raised a purple flag. They warn of dangerous marine life.