Winter’s extreme low tides reveal acres of hard-packed sand on some beaches but this is no desert. Instead of crouching among exposed rocky tidepools, elbow to elbow with the hoi polloi, head to La Jolla Shores to take a sandy beach walk. You may reap even more sea life finds despite the moonscape appearance. True, seaweed and other algae can’t subsist on a sandy beach because there’s no fixed anchorage, but clumps and fragments of red, green and brown photosynthesizers end up on shore by surge, surf and currents. Though the salty foliage is interesting in itself, closer inspection may reveal a host of hapless hitchhikers. As with all nature exploration, take only pictures, leave only footprints. — Judith Lea Garfield, biologist and underwater photographer, has authored two natural history books about the underwater park off La Jolla Cove and La Jolla Shores. www.judith.garfield.org. Questions, comments or suggestions? E-mail [email protected].