Stingrays have invaded San Diego's shoreline, and lifeguards are warning people to say alert.
More than 130 people have been stung in the last weeks. Many of them were stung at La Jolla Shores -- as many as 55 in one day. Some have been stung at nearby Torrey Pines State Beach as well as farther south at Ocean Beach.
So far, three people have been hospitalized after being stung. Lifeguards are asking people to do the stingray shuffle -- shuffle your feet into the water -- which alerts the sting rays that people are nearby, sending them in the opposite direction.