Advisories were posted on local beaches Friday after a small shark bit a surfer in the water off Shell Beach.
Derek Crane, 19, of San Luis Obispo suffered a laceration to his left foot after he was bitten about 6:50 p.m. Friday. A friend drove him to a nearby hospital.
Authorities said Crane described an approximately four-foot shark, brown in color with dark spots. Investigators said they determined it was a credible dangerous marine animal sighting.
Beaches will remain open, officials said. Authorities encourage citizens to exercise caution when in the ocean.