The eastern oyster Crassostrea virginica is a temperate reef‐building bivalve that provides an array of ecosystem services. Efforts to restore eastern oyster have been increasing, highlighting the need for standardized monitoring metrics across projects and regions. Our objective was to estimate the efficiency of hydraulic patent tongs for estimating eastern oyster density on restoration sites in Harris Creek, Maryland. We sampled eastern oysters using a diver and hydraulic patent tongs and estimated differences in density estimates between the two gears using a mixed‐effects generalized linear model. On average, density estimates from hydraulic patent tongs were only 30% of those from the diver, which was substantially lower than previous studies. Given the widespread use of hydraulic patent tongs in eastern oyster research and management, a better understanding of the efficiency of hydraulic patent tongs is needed.