A spate of shark encounters and sightings has led to a flurry of warnings to surfers and swimmers along the Central Coast, including at Santa Barbara Island in Channel Islands National Park.

The Santa Barbara Island Landing Cove was the scene of a recent great white shark attack on a California sea lion.

The Santa Barbara Island Landing Cove was the scene of a recent great white shark attack on a California sea lion. (Chuck Graham / Noozhawk photo)

Despite the heightened awareness, a surfer was bitten by a shark Friday evening near Silver Shoals off Shell Beach. Derek Crane, 19, of San Luis Obispo, was bitten on the foot by what he described as a four-foot brown shark with dark spots. A friend drove him to a nearby hospital for treatment of a laceration.

National park officials last week issued a public notice for those wishing to visit Santa Barbara Island. Great white sharks have been observed in the area attacking California sea lions although there have been no shark attacks on humans there.

There have been three known attacks on sea lions by great white sharks in the past few months, including one at the Santa Barbara Island Landing Cove, the only access point on the one-square-mile isle. Hordes of sea lions enjoy hauling out on the barnacle-encrusted rocks surrounding the cove. Two other attacks occurred off Cat Canyon on the rugged southeast side of the island.

Officials warned the public to enter the water at their own risk until further notice. The windswept island is a popular destination for day hikers, campers, divers and kayakers.

Santa Barbara Island is home to one of the largest California sea lion rookeries in the state — numbering in the thousands — and a smaller northern elephant seal rookery with hundreds of the animals.

Noozhawk contributor and local freelance writer Chuck Graham is editor of Deep magazine.