Common Name: Eastern oyster (sometimes called American or Virginia oyster)
Latin Name: Crassostrea virginica
Description: A prolific bivalve mollusk with thick irregular grayish-white shells with concentric ridges. The left (or bottom) shell is cupped with a purple muscle scar inside. The right (or top) shell is smaller and flatter.
Size/weight: Shells generally are 3 to 5 inches long
Range: Eastern North America, from the Gulf of St. Lawrence to the Gulf of Mexico
Habitat: Estuarine or salty water, in intertidal and subtidal zones. They can grow in great beds or reefs, with new immature animals "setting" on old empty shells. Oyster reefs provide bottom habitat for other marine invertebrates and fish species.
Diet: Oysters are filter-feeders. They open their shell & pump in water, which draws planktonic food in as well. (Oysters filter so much water that a large population of oysters can effectively help keep a body of water clean.)
Predators: Sea stars, crabs, oyster drills and other snails, some fish, humans.
Note: The Eastern oyster was designated as Connecticut's state shellfish in 1989.
Norwalk and the Eastern oyster go way back. The city’s Oyster Shell Park, which extends up the pathway along the Norwalk River north of the Aquarium, was once the site of a native American oyster midden – a place where the local tribe piled up its empty oyster shells.
The waters of Long Island Sound just off of Norwalk are a perfect place for oysters, offering just the right temperatures, salinities, substrate and currents, plus a lack of severe storms. Oysters grow wild, but – even by the early 1700s – were being farmed as well. Oystering boomed through the 1800s, serving as a huge economic driver for Connecticut’s shoreline communities. And these just weren’t any oysters. The oystermen were farming a particular variety with a deliciously distinct taste they called Bluepoints. They could barely keep up with the demand.
(In The Maritime Aquarium at our Toy Boat-Making workshop, check out a 1937 Works Progress Administration – or WPA – mural of an oyster-shucking operation.)
Oystering in the Sound hit hard times in the early half of the 20th century (mainly from pollution) and in the late 1990s (from parasites). But the industry is thriving again today, with two of Connecticut’s biggest companies based on either side of the Norwalk harbor. Oyster connoisseurs still rank Bluepoints among the best in the world. The legendary Oyster Bar restaurant in Grand Central Station reportedly serves 1,000 Norwalk oysters a day – one-fourth of them Bluepoints.
See oyster shells in one of the salt-marsh gallery exhibits, and touch them at our Intertidal Touch Tank.