The SFGS is fairly well studied, and no populations have been recorded in this area, although it might have once lived in the swale ponds across the highway at Ocean View Farms. It eats mainly California Tree Frogs when young (common enough around here - they're the ones you hear each spring) and California Red-legged frogs when mature (none known in the immediate area of Montara Beach, although they are found in Green Valley to the North and down by Pillar Point Marsh and Denniston creek to the south)

If the head is red or partially so and the red bands are broken, it may have been a cross breed, not uncommon where the SF and California Red-sided co-exist.

Check the pictures carefully - if it is a SFGS or a cross breed, it could be a very important discovery - there are only 5 known small populations of this snake left in the entire world, and the US Fish&Wildlife Service considers it extremely endangered of extinction.