Morphometric character variation of the blue swimming crab (Portunus pelagicus Linnaeus, 1758) population in western and eastern part of Java Sea

Abstract

The blue swimming crab (Portunus pelagicus Linnaeus, 1758) inhabits coastal waters with sandy or muddy substrates of Southeast Asia. Aquatic environment and fishing intensity might influence the variation in morphometric characters of species as a form of adaptation and might characterize the stock unit as well. This study was aimed to analyze the morphometric variation of the blue swimming crab (BSC) population in western and eastern parts of Java Sea as part of Fisheries Management Area (FMA 712) of Indonesia. The representative crab sample for both males and females were taken randomly from three different locations, i.e. East Lampung, Rembang, and Southern Madura Island. Those samples were analyzed with a method called “conventional morphometric method”. Result of the Kruskal-Wallis test showed that 10 characters were significantly different between male and female crabs. The cluster analysis also showed that the crabs in East Lampung and Rembang had high similarities which tended to be close population, while Southern Madura’s crabs were seemed to be dissimilar. In addition, discriminant analyses also showed that the BSC population in Southern Madura was different from the other two populations, indicating that the BSC population of Southern Madura is a different stock unit.