Survival and growth of post-settlement juveniles of the spider crab Maja brachydactyla (Brachyura: Majoidea) reared under individual culture system

The effect of an individual culture system on survival and growth of juvenile crab stages 1–8 of the majid crab Maja brachydactyla Balss, 1922 was studied using larvae obtained from adult individuals collected in the NE Atlantic. The juvenile stages were cultured individually from a megalopal stage using a semi-open recirculation system. Forty-eight percent of the megalopae moulted to first juvenile stage. Detailed growth data have been obtained for each juvenile stage. Juvenile development up to juvenile crab stage 8 (C1–C8) at 20 °C lasted 117.5 ± 7.5 days. Survival was high during the whole experiment: 43.75% of C1 survived to perform the moult to C8. Moult increment values (%CL) were similar in all the juvenile stages (27.90–37.04%). Intermoult duration (9.37 ± 1.04 to 33.5 ± 2.64 days) increased sharply from stage 6, and the specific growth rate (SGR) diminished due to the significant increase of the intermoult period.