We still do not know one thousan dt of what nature has revealed to us h of one percent . ~ A l b e r t E i n s te i n
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Knobbed whelk
What Have We Here? Juvenile ghost crab
Sand shark tooth
Moon snail
A Beachcomber’s Guide to Treasures in the Sand
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By Lenore Tedesco, Executive Director of The Wetlands Institute
hat can be more relaxing and exciting than an early-morning stroll along our beachfront? The warm breezes, sounds of the waves, and freedom from the everyday grind makes our quiet time on the beach so special. The serendipitous uncovering of Mother Nature’s gifts from the sea adds another level of joy. Finding shells and other signs of the many animals that live, hunt, burrow and reproduce in this challenging and remarkable shoreline ecosystem is an exercise in discovery. We enjoy finding evidence of the animals that call this environment home, and assigning a name to what we find makes it all the more special. Join us on this journey, and the next time you are walking the beach, see how many of these creatures (or evidence of their presence) you can find. We are going to focus on the more unusual items you may find. The easiest way to catalog these animals is by breaking them into a few basic categories.
BIVALVES: These are mollusks with two shells, but the shells are most commonly found as single halves along the beach. Surf Clams are the largest bivalves found in the western North Atlantic and can grow to almost 9 inches. They are very common at Seven Mile Beach and seem to be a collectors’ favorite for soap dishes and knickknacks. They are found in sandy bottoms in waters up to 8 feet deep and burrow just below the surface. They are filter feeders and eat microscopic plants and animals. They wash up on our beaches following storms and with dredged material. Coquina Clams (Donax) are a small species of colorful clam that occurs in very high concentrations in the surf zone. They align their shells vertically in the sand. When the waves wash these clams out of the sand, they can quickly dig back in, only to be exposed by the next wave. They are a sign of a healthy
Knobbed whelk
beach and are an important food source for moon snails, shorebirds, and ghost crabs. Scientists are concerned that this species is becoming less common with repetitive beach nourishment. Watching them borrow into the sand after waves is a real treat. SNAILS: A large variety of snails can be found on our Atlantic beaches and a similarly large number, albeit different ones, are found in the marshes. Snails are mollusks with one shell and most have an operculum, which means “little lid.” The operculum acts like a trapdoor, closing off the shell to protect the snail from predators and also from drying out if they get caught out of the water. You can sometimes find opercula on the beach. Most snails are carnivorous animals that have a strong muscular foot that helps them move through the sand. Moon snails are nocturnal and move through the sand of the swash zone in search of their next meal. They have a radula, a sharp toothy-tongue that they use to drill through the shell of their prey: other mollusks. When you find a shell with a perfectly round hole in it, it could have been the meal of a moon snail. Whelks are the largest snails that live along our beaches. When they are alive, they cruise the intertidal zone and tide pools looking for food. They use the sharp edges of their shells to pry open the shells continued on page 62
Adult ghost crab
Seven Mile Times July 2023
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