I know not everyone likes snakes but we share the Mendonoma Coast with several species. Peter Baye recently photographed this CA red-sided Garter Snake on the Mendocino Coast. Its Latin name sounds like a Harry Potter spell - Thamnophis sirtalis infernalis.
This snake is a good swimmer as you will see in C'Anna Bergman-Hill's photo below. It has the ability to eat Pacific Newts, which are poisonous to most other predators. It has toxin in its saliva that it uses to capture its prey, but this snake is considered harmless to humans.