Sex Ratio And Size At First Maturity Of Blue Swimming Crab (Portunus pelagicus) at Salemo Island, South Sulawesi

Blue swimming crab (Portunus pelagicus) is an economical valuable fisheries important commodity due to high demand and availability jobs created for the fishermen. Therefore blue swimming crab has been heavily exploited from Salemo Island. This study aimed at comparing the sex ratio and the size at first maturity of blue swimming crab caught in mangrove ecosystems, coral reefs, and seagrass. Sex ratio was analyzed using chi square test and the size at first maturity was analyzed using the Spearman-Karber formula. The results showed the sex ratio of males and females blue swimming crab caught in every ecosystem is balanced. The size at first maturity of blue swimming crab caught in mangrove, seagrass and coral reefs, each to the male 81.08 mm, 102.36 mm and 102.87 mm in width and size of female 94.54 mm, 83.35 mm, 98.31 mm width. In a reference to government regulations, the blue male swimming crab caught in the coral reef and seagrass ecosystems have yet to size at first maturity is allowed to be captured.