Distribution, Recruitment, and Growth of the Black-Lip Pearl Oyster, Pinctada margaritifera, in Kane'ohe Bay, O'ahu, Hawai'i

Abstract

Stocks of Hawaiian black-lip pearl oysters, Pinetada margaritifera (Linnaeus, 1758), appear to have been depleted by overfishing and environmental degradation. Permanent survey transect sites were set up in Kane'ohe Bay in 1989 to monitor changes in the status of stocks. Only 17 pearl oysters were found in 1989. Transects were resurveyed in 1997, and 22 pearl oysters were counted. Most were found on the slopes of patch reefs around the Sampan Channel in 2-6 m depth. Recruitment is low. Standing stock estimated from observed densities on transects in 1997 and the extent of available habitat is about 950 individuals. The size distribution of pearl oysters on transects indicates that they are fished, despite legal protection. Growth of Pinetada margaritifera in Kane'ohe Bay is comparable with that in other locations. The prospects for commercial culture of black pearls in Kane'ohe Bay are limited by environmental constraints and the heavy recreational use of the bay.