The surfer believes he spotted a great white like this one. Photo credit: Terry Goss/Wiki Commons

A shark advisory was issued Saturday after a surfer spotted one at Silver Strand State Beach, Coronado lifeguards confirmed .

The surfer said the shark appeared to be a great white about 10 feet long, according to a Facebook post.

He claims to have worked on fishing boats for many years and has had several encounters with great white sharks previously, stated the post.

“He knows what he saw,” added the post.

Coronado lifeguards explained that the advisory does not apply to the beaches in Coronado. There is only an advisory in effect at Silver Strand State Beach in San Diego, just south of Coronado’s beaches.

No further information was immediately available.