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An Overview of Common Seashells Found in the United States

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"An Overview of Common Seashells Found in the United States"
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An overview of the common seashells of the United States might begin with the state shells of fourteen coastal states. However, California and Hawaii, where shells are abundant and admired, lack designated state shells. Also, many state shells are the shell of more than one state, and several were plainly chosen because of the popularity of the seafood contained within, not because of the grace of the shell.

Nevertheless, the state shells are a place to start. Another is the local beach, where shells hide among the wrack at the tide line, cling to the rocks, and can be seen with their fascinating inhabitants in tide pools at low water.

West coast shells

At the feet of rocky bluffs and tide-sprayed rocks along the west coast, California blue mussels cling in huge colonies. The long oval bivalve shells are dark blue, though they appear nearly black when wet. Inside is a pearly luster. They cling tenaciously with their byssus, their beard, which must be removed before they can be eaten. They are delicious if not overcooked, but are also poisonous at certain seasons, when they take up the red tide organisms that cause paralytic shellfish poisoning.

California, Washington, and Oregon also have clams and oysters, though these are not as easy to harvest as mussels. Nearby tide pools will often offer views of starfish and urchins, though of course it’s a shame to take them alive. Abalone, once common, are now rare.

Oregon’s state shell, the Oregon hairy triton, is found from Alaska to California. This light brown aquatic snail is five inches or less long, is covered with spirals of spikes, and is a predator of the region below low tide.

One well-known west coast shell is dentalia, which is a type of long narrow shell, but also a term for a kind of American Indian bead work, which uses shell. A dentalia shell harvested near Vancouver Island was once preferred for this art, but now shells imported from Japan are common.

Alaska shells include the Iceland cockle, a yellowish-gray bivalve with subtle bands of color and the Pacific sea scallop, a flat, ridged, brownish pink shell.

Gulf coast

The state shell of Texas is the prickly whelk, Busycon perversum pulleyi. This marine snail shell is shaped like a very stylized ice cream cone, with a spiral of ridges where the scoop should be. Also called the lightning whelk, it is streaked with brown and white, and can grow to 16 inches long. It preys on clams and other bivalves. Gulls and crabs prey on it.

Other clams, mussels, and scallops are common in Texas and along the gulf coast. The delicate coquina shells are smaller than a penny, while the giant eastern murex looks something like a pale, lumpy lightning whelk. The hooked mussel is nearly the color of the west coast mussel, but the shell looks as if it was pulled sideways, nearly into a paisley shape.

Mississippi’s state shell is the Eastern oyster. It was treasured as seafood, but its population has declined with over-harvesting and disease. It is being successfully farmed however. Also the state shell of Virginia and Connecticut, this oyster has a wide range. Its infrequent pearls are of no commercial value.

The west coast of Florida is a famous place to hunt shells. The Florida state shell, the Horse Conch, is found there. Not actually a conch, this shell is a giant snail, the largest gastropod in American waters. It is bright orange in youth, but its colors dull with maturity. It eats other gastropods, such beautiful creatures as the lightning whelk, the tulip shell, and the queen conch. Mayan art shows the horse conch shell being used as a trumpet.

East coast

On the east coast of Florida many of the same shells are found. The lettered olive, a long narrow snail shell with zigzag markings that resemble writing is reasonably common, along with the Florida fighting conch, a true conch that may be four and a half inches long.

The lettered olive is the state shell of South Carolina, but the state shell of Georgia and New Jersey is the knobbed whelk. It’s a curled snail shell that may be a foot long, with a vivid orange lining at its opening. The shell is studded with rough knobs, rather than points. It eats oysters, clams, prying open their common shells.

North Carolina honors the Scotch bonnet as its state shell. The shell shape vaguely resembles that of the Scottish tam o’shanter if set with its opening facing down, and is marked into squares that are colored brown and white in a way that distantly resembles plaid. This predator snail preys on sea urchins and other sea life.

New York honors the classic shell of the Atlantic Bay Scallop, and its delicious meat. This bivalve shell resembles that pictured in Botticelli’s Birth of Venus, though Botticelli never saw New York.

The state shell of Massachusetts is the wrinkled whelk, which is beautifully banded or corded. Some hesitate to eat this whelk, at least at certain seasons. Rhode Island is a center of production for the Northern quahog, a clam respected for its eating qualities and honored as the state shell. The shells were made into sacred beads, wampum, by the American Indians, and often used in trade with the first settlers from Europe.


The beautiful spotted tiger cowrie of the reef feeds on algae at night. By day, it hides beneath the membrane of its mantle, which continually builds up the shell in thin layers, maintaining a silky sheen. Without the cowries, there would be too much algae, and without the algae there would be no cowries. Hawaii’s waters hold many beautiful varieties of cowrie, as seen on this great site.

Like many peoples, the Hawaiians used their triton shell, Triton’s Trumpet, as a signal horn. Tritons keep the crown of horns starfish in check, again maintaining the balance.

Several Hawaiian cone shells actually deliver a poison sting. They prey on other sea creatures, but can harm people. One example is the conus bandanus, a frustrum cone in shape with a shell that looks like a mosaic of white and brown.

Conches, tops, and bubble shells are among the other magnificent shells of Hawaii.

Anywhere on the coast, shells can be found. They are deposited at the high tide line, revealed at low tide, and thrown up in abundance by storms. Some of the most beautiful are sand scrubbed fragments.

Sanibel in Florida, all of Hawaii, and coastal California are popular places to look for shells, but any beach will do. In fact, like anglers, many shellers do not even care if they get a good shell. Just looking is a day at the beach.

Seashells by R. Tucker Abbott

More about this author: Janet Grischy

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