A word of warning to Central Coast surfers: Keep your toes up and your eyes on the horizon.

A 16-foot great white shark was seen circling the Cayucos Pier on Sept. 30. The sighting, the fourth this year, prompted county officials to post warning signs that cautioned beachgoers of the potential risks of entering the ocean.

The next day, Oct. 1, a dead sea otter with bite marks consistent with a shark attack washed ashore at the Morro Bay Strand State Beach.

Michael Harris, an environmental scientist with the Department of Fish and Game who inspects sea otter deaths from Cambria to Point Conception, said he was nearly 100 percent positive that the animal died from shark-inflicted wounds.

"Though [the otter] was heavily scavenged and most of the abdominal region was mostly gone, I'm as sure as I can be it was a shark," he said.

Harris added that this type of shark-related mauling is common this time of year.

"We definitely have an increase of shark-related mortality in sea otters during late summer, early fall," he said. "It's most likely related to the migratory patterns of white sharks."

Despite the associated risks with sharks, one local surfer said the recent sightings have not kept him or many others out of the water.

"This stuff happens," said Chad Hennigh, a Central Coast waterman and owner of the Cayucos surf shop Good Clean Fun Surf and Sport. "It was quite the buzz for the day, but then it was over. There were 30 to 40 surfers in the water the next day."

According to the International Shark Attack File, there are about 70 to 100 shark attacks annually, resulting in about five to 15 deaths.

Although the risk of a shark attack is small, the chances of being attacked can be reduced if people swim in groups, avoid being in the water during darkness or twilight hours, and refrain from wearing shiny jewelry.

If attacked, experts advise defending yourself by hitting the shark's eyes, gills, and nose.