Genetic population subdivision of the 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 commodities with an export value for Indonesia and an increasing global market demand, annually. However, the data of genetic diversity and their spatial connectivity of populations in Indonesia are not yet known, even when it is important to inform stock unit management and sustainable use. This study aimed to determine the genetic diversity and differentiation of blue swimming crabs across Indonesian populations in different Fishery Management Area (FMA), and their spatial genetic connectivity, as well as to deliver implications for sustainable fishery. A total of 297 individuals were collected and amplified using cytochrome oxidase I mitochondrial DNA. This study has showed the highest values for haplotype and nucleotide diversity in the eastern part of Indonesia, where exploitation is relatively low. Significant genetic differentiation between populations (F-ST = 0.954; p < 0.001) and the fisheries management areas (F-ST = 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 stock units, and preferably different fisheries management plans and actions across the region thoroughly and simultaneously. This would be effective for management and their sustainable conservation.

Automated summary

This study aimed to determine the genetic diversity and differentiation of the blue swimming crab across Indonesian populations in different Fishery Management Areas and their spatial genetic connectivity. Results showed that the eastern part of Indonesia has the highest values for haplotype and nucleotide diversity, with significant genetic differentiation between populations and management areas, and low spatial connectivity. This suggests the presence of multiple stock units for blue swimming crabs in Indonesia, which would require different management plans across the region for sustainable conservation.