Effect of brine-shrimp numbers on growth and survival of early-stage phyllosoma larvae of the rock lobster Jasus edwardsii

Stages I to VI phyllosoma larvae of the rock lobster Jasus edwardsii were fed daily with a fixed number (1, 2, 4, 8, 12 or 16) of 2–3 mm brine shrimps (Artemia salina) to determine the optimum requirement for growth and survival. For stages I and II the threshold below which food became limiting, measured as a significant delay in moulting, was <2 brine shrimps per day. For stage III the threshold was 4 brine shrimps per day, for stages IV and V it was 8 brine shrimps per day and for stage VI, 12 brine shrimps per day. Growth at the moult was reduced when food was limiting. The feeding rate reduced immediately before the moult and this was most evident for stages V and VI. The results are discussed in relation to large scale culture of phyllosoma larvae.