Life in a Sea Cave Sea caves may abound with life, both on their walls and floors. Besides the kind of critters seen in normal tidepools, such as anemones, starfish, and sponges, sea caves with dark zones may harbor organisms not commonly seen. While spacious inside, they are only moderate in length, neither of them exceeding 250 feet from end to end. The world's largest known sea cave is Painted Cave on California's Santa Cruz Island. It is 1227 feet long and large enough to take a 20-foot boat inside.
Sea lions inhabit the ledges in the back of the chamber much of the year.