Oysters 101
The eastern oyster (Crassostrea virginica) lives in estuaries along the Atlantic and Gulf coasts and has served as an important food source for centuries. While oysters are valued for their culinary uses, they also play a vital ecological role as filter-feeders. Related to clams and mussels, oysters have the ability to consume extremely small particles like phytoplankton from the water. By filtering out these particles in the water, oysters help clean the water they live in! These natural benefits, known as ecosystem services, support diverse plant and animal life in the estuary.
In addition to their water-filtering abilities, oysters are also exceptional reef builders. They reproduce by releasing eggs and sperm into the water, where fertilization occurs naturally. The resulting larvae float until they find a suitable place to settle, usually on other oysters! As generations of oysters grow on top of each other, large reefs can form, sometimes growing many feet high and miles wide. These reefs provide habitat, shelter, and feeding grounds for numerous species, including blue crabs, striped bass, and fish. Much like coral reefs in tropical regions, oyster reefs help sustain rich and diverse biological communities. Healthy oyster reefs also support local economies through recreational and commercial fisheries!
Oyster decline in the Estuary
In the Delaware Estuary, oysters were abundant until the 1950s, when the disease MSX killed more than 95 % of the population. A second oyster disease, Dermo, emerged in the 1990s, and both continue to affect oyster populations today. Although the current oyster population is only a fraction of its historic size, oysters remain resilient and continue to grow and reproduce. Most reefs within the Delaware Estuary are located in New Jersey’s portion of the Delaware Bay, but oysters will settle throughout the estuary wherever they can find habitat. Today’s commercial harvests are considered sustainable, thanks to collaboration among researchers, resource managers, and state officials who use scientific data to guide decision making.
