Sampling efficiency of two oyster fishing gears, patent tongs and an oyster dredge, were compared in reference to diver-harvested quadrats in Chesapeake Bay, which supports important harvests of eastern oyster Crassosrrea virginica. Mean densities of spat (0$35 mm), small oysters (>35 mm to 75 mm), marketable oysters (>75 mm), and all oysters (three size-groups combined) estimated from patent tong samples were not significantly different from those derived from diver-harvested quadrat samples. In contrast, the densities estimated from dredge samples were low, only 2-32% of the diver estimates. Accordingly, patent tongs are recommended as the sampling gear for estimating eastern oyster stock abundance in the Maryland portion of Chesapeake Bay. |