Population characteristics based on distribution of natural mother of black-lip pearl oyster, Pinctada margaritifera (L.), in Chuuk Lagoon, FSM

Abstract

A survey within nearshore habitats in Chuuk lagoon in twenty six stations showed that Pinctada margaritifera is widely distributed in shallow lagoons from 2000 to 2006. It was most abundant in southern parts of Weno Island within sheltered back reefs and lagoon, and on an intertidal reef flat and back reef also. Based on the multi-variate analysis, bottom habitats of the study area were classified into four type of habitats such as Acropora dominated, dead coral bed, and coralline sand bottom area. The spatial distribution of the oyster seemed to be closely related to habitat types, however no difference in shell size was observed among habitats. The overall means (n=236) of shell length and total weight of the oyster were 124 mm and 286.4 gWWt, respectively. The mean density of the oyster was 0.3 inds./100m2 and the stock size of the oyster which can be directly put to pearling industry was estimated to 457,000 individuals.