Mussels inhabit an area between high tide and low tide called the intertidal zone.
The splash of surf keeps mussels fed by bringing them a constant supply of plankton that they filter out of the water. If a day in the tidal zone leaves you yearning for nutriment, try the delicious steamed mussels at Del Mar's Torrey Pines Caf . When the tide is really low, you're more likely to find slug-shaped nudibranch, spiky sea urchins and starfish. After having them for lunch, nudibranch incorporate the anemone's paralysis-inducing cells into their own bodies and thus gain protection against predators. Not a bad hustle for something that's only an inch long and soft as a sponge.