Invertebrates

Arks are boxy bivalves with thick, white, ribbed shells. They live in the salty waters of the lower Chesapeake Bay.

The Atlantic oyster drill is a small, predatory snail with a pointed, ribbed shell. It lives on reefs, rocks and pilings throughout the middle and lower Chesapeake Bay.

The Atlantic ribbed mussel is a bivalve with dark, ribbed shells. It is found in low marshes and mud flats throughout the middle and lower Chesapeake Bay.

The bay scallop is a bivalve that lives in the lower Chesapeake Bay’s salty, shallow waters. Its ribbed, multicolored shells are often found on beaches throughout the lower Bay.

The brief squid is a small, free-swimming mollusk with a soft body and arm-like tentacles. It lives throughout the lower Chesapeake Bay.

Also known as the American or Virginia oyster, the eastern oyster is a bivalve with two rough, whitish shells. It forms reefs in brackish and salty waters throughout the Chesapeake Bay.

Gould’s shipworm is a bivalve with a long, worm-like body. It lives within untreated wood, such as pilings and driftwood, in the middle and lower Chesapeake Bay.

The hard clam is a bivalve with thick, ridged, rounded shells. It lives in the salty waters of the lower Chesapeake Bay.

The hooked mussel is a bivalve whose dark, ridged shell is strongly curved, or “hooked” on one end. It is prolific in oyster reefs—often “wrapping up” oysters—and can outnumber the amount of oysters by several fold.

Knobbed whelks are marine gastropods that live in tidal estuaries along the Atlantic coast. Their spiral shells can range in color from grayish white to tan.

Macoma clams are tiny bivalves with thin, chalky white shells. They live buried in the sand or mud in the shallow waters of the middle and lower Chesapeake Bay.

The marsh periwinkle is a small snail with a thick, spiraling shell. It lives in tidal marshes and wetlands throughout the middle and lower Chesapeake Bay.

Sea slugs are soft-bodied, shell-less mollusks that live throughout the Chesapeake Bay.

The soft shell clam is a bivalve with thin, elongated shells. It lives buried in soft sediments in the middle Chesapeake Bay.

The veined rapa whelk is a large, predatory snail that lives in the lower Chesapeake Bay. It is an invasive species.

The zebra mussel is a tiny bivalve with zebra-like stripes on its triangular shell. It lives in freshwater lakes, rivers, streams and reservoirs in parts of the Chesapeake Bay watershed. It is a non-native and invasive species.