The San Francisco Chronicle spoke to local fishermen who had two separate encounters with what they believe were great white sharks.
The first occurred on Saturday when fisherman, Rich Fitzpatrick, saw a fresh, half-eaten seal floating off Marin.
As Fitzpatrick moved his vessel to look closer, the shark returned for the rest of its meal.
"To me, it's exciting to see them. I'm in awe," Fitzpatrick told the newspaper.
In Southern California, Santa Barbara beaches were closed last week after a surfer spotted a great white and a harbor seal was found with wounds from an apparent shark attack, the Los Angeles Times reported.
An area marine center reported six shark sightings this summer off Santa Barbara County beaches.
"They are not scared of anything. They just have one thing on their mind, and that's to eat," said Fitzpatrick.
The second encounter was reported on Sunday afternoon when a charter boat spotted a great white munching aggresssively on a school of salmon.
KCBS Television reported on July 19, a 14-foot great white was sighted off the coast of Aptos. California State Parks rangers said the shark was seen about 20 yards off the coast near the Seascape and Rio Del Mar beaches.