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Document Type

Book Chapter


Virginia Institute of Marine Science


Mason, W. T. and K. C. Flynn, eds

Publication Date


Book Title

The Potomac Estuary. Biology Resources, Trends and Options. Proceedings of a Symposium; Alexandria, Virginia; 1975.


Interstate Commission on the Potomac River Basin


The Potomac and its tributaries support many species of molluscs which are important sources of food for benthic invertebrates, fish, and waterfowl. However, only two species, the American oyster Crassostrea virginica and the soft clam Mya arenaria are harvested for commercial purposes. A third species, the brackish water clam Rangia cuneata occurs locally in tremendous concentrations, but it is not utilized as a food source. Nevertheless, this species is regarded as a potential source of food for people.

During the past six to eight years, commercial landings of both the oyster and the soft clam have dropped from high to extremely low levels. The cause of this decline may be partially explained for oysters, but the reason for the decline for soft clams is not apparent. The brackish water clam Rangia, a recent introduction into the Potomac, remains at high levels of abundance.

In this discussion, emphasis will be placed on the oyster since this species has received the most study.

Publication Statement

p. 88-94.

The Shellfish Fisheries of the Potomac River