An announcement from a police helicopter on Wednesday near Capistrano Beach, California:
"You are paddleboarding next to approximately 15 great white sharks. They are advising you exit the water in a calm manner. The sharks are as close as the surfline." From the OC Register:
(Orange County Lifeguards Chief Jason) Young said it was not an ocean closure, which occurs when sharks are more than 8-foot long and/or are acting aggressively in the water.
"We haven't had any reports of anyone being bumped or charged, just observations of them either swimming or breaching," he said.