Abundance and spatial distribution of blue swimming crab (Portunus pelagicus) larvae during east monsoon in the East Lampung waters, Indonesia
Kembaren DD, Zairion, Kamal MM, Wardiatno Y. 2018. Abundance and spatial distribution of blue swimming crab (Portunuspelagicus) larvae during east monsoon in the East Lampung waters, Indonesia. Biodiversitas 19: 1326-1333. The blue swimmingcrab/BSC, Portunus pelagicus, is an economically important species in fishery industry and continuously being exploited, particularly inthe East Lampung waters. BSC research in Indonesia during the last decade was only restricted to the adult phase, while research ontheir larval dynamics in nature has not been done yet. This study aimed to assess the abundance and the distribution of BSC larvae, andto describe their correlation to its environmental conditions. This study was conducted in June 2017 (during east monsoon) in the EastLampung waters. Sampling was done in surface water during the daylight hours on nine sites with three replicates on each site. Planktonabundance and oceanographic profile were also recorded from the same sampling site. The result from this study showed that the waterquality from the environment was suitable for the development of BSC larvae. The abundance of the early-stage larvae (Z1-Z3) wasrelatively higher than the late-stage larvae (Z4 and M). The larval stages of BSC were dispersed and completed their development in themid-shore and offshore waters. There was a tendency that the early-stage was more abundant in the northern part, while the late-stagewas more abundant in the southern part of the study area. The highest larval abundance was found in the mid-shore, particularly in sitenumber five, which was influenced by the water mass density and current direction during the east monsoon. Moreover, oxygenconcentration and salinity of the water environment influenced the early-stage larvae abundance more than the late-stages abundance.