Genetic population subdivision of Blue Swimming Crab (Portunus pelagicus) across Indonesia inferred from mitochondrial DNA: implication to sustainable fishery

The blue swimming crab (BSC), Portunus pelagicus (Linnaeus 1758), inhabits coastal areas of Southeast and East Asia, and is one of high fisheries commodity with export value for Indonesia and global market demand increasing annually. However, the data of genetic diversity and their spatial connectivity of populations in Indonesia are not yet known, which is important to inform unit stock management and sustainable fisheries. This study aimed to determine genetic diversity and differentiation of blue swimming crab across Indonesia populations under different Fishery Management Area, and their spatial genetic connectivity, as well as implications for sustainable fishery. A total of 297 individuals were amplified using cytochrome oxidase I mitochondrial DNA. This study shown highest value of haplotype and nucleotide diversity in the eastern part of Indonesia, where exploitation is relatively low. Significant genetic differentiation between populations (FST = 0.954; p < 0.001) and the fishery management regions (FST = 0.964; p < 0.001) were revealed. Low spatial connectivity was observed between populations in a distance of at least more than 60 kilometers. This study suggests that BSC populations in Indonesia likely have several unit stock, and preferably different fisheries management plan and action across the region thoroughly and simultaneously is effective for management and their sustainable conservation.