These tide pools provide a refuge for crabs, fish, and other seashore creatures that need to remain in seawater. Such animals live in the tide pools until the incoming tide again covers the shore. Most animals that live on rocky shores eat plankton. A few, including rock crabs and starfish, feed on the creatures that eat the plankton. Life on muddy shores.
Most muddy seashores lie in bays, where they are protected from strong waves.
Rivers empty into many of these bays, decreasing the saltiness of the sea water. Crabs and turtles live among these plants. Clams and worms burrow into the muddy bottom of the seashores. Life on sandy shores. Sandy beaches have fewer forms of life than do rocky or muddy shores.