One winter storm can wash away a month's work building a seawall. It is now illegal in Maine to build seawalls and homes where they will be threatened by waves. For animals which must find a home on the beach the best strategy is to dig in. The sharp shells and long foot of the razor clam can tunnel through several feet of sand in seconds. Large gills allow them to breathe under the moist sand.
Sand worms excavate deep U-shaped tunnels.
Sand dollars barely cover themselves with sand. Meat-eating moon snails plow through the sand looking for clams and periwinkles to drill and devour. In the spring the mother moon snail deposits a delicate sand collar of sand and glue as her egg case. The strand line is where dead seaweed and empty shells collect at high tide. Here are the remains of those that lost the battle with the sea.