Assessment of deep water stocks of pearl oysters at Takapoto Atoll (Tuamotu Archipelago, French Polynesia)

An assessment of natural stocks of the commercially important black pearl o yster, Pinctada margaritifera, was conducted in the lagoon of Takapoto Atol l, French Polynesia. The sampling methodology combined estimates of reef ar ea from remote sensing, depth profiles across the lagoon, and in situ sampl ing using scuba. Confidence limits around estimates of mean oyster density began to stabilize after ten dives, and did not decrease further after 30. Densities of oysters increased steadily with depth, ranging from a mean of 1 per 100 m(2) at 0-10 m to 8/100 m at 30-40 m. More than half of the stock occurred at depths greater than 30 m. The total stock was estimated to be 4.3 +/- 0.67 million, equivalent to 834 metric tonnes (including shells).