The red octopus (Octopus rubescens) is a highly developed marine mollusk that breeds offshore from Point Reyes National Seashore and Golden Gate National Recreation Area. It is a very elusive species and almost never seen by humans. Like other species of octopus, it can change its color quickly – in a fraction of a second – to defend itself from predators. It can also change its skin texture to match the surface of smooth sand or rough rocks. Researchers consider octopuses to be the most intelligent invertebrates.

The California market squid (Loligo opalescens) is a seasonal resident to California, and during the summer months it returns to the shoreline to deposit egg capsules on the shallow seafloor and then die. Like cephalopods, market squid can exhibit dramatic color changes. Squid are also the fastest swimmers among marine invertebrates, using water for jet propulsion. This species makes up one of California’s largest fisheries.