Production of juvenile redclaw crayfish, Cherax quadricarinatus (von Martens)(Decapoda, Parastacidae) III. managed pond production trials

Commercial-scale production of juvenile redclaw crayfish was conducted in earthen ponds. Based upon the results of previous experimental studies in tanks and aquaria, earthen ponds (1300 and 2600 m²) were furnished with juvenile crayfish shelters, and were prepared and managed to maximise availability of zooplankton. Juvenile redclaw were introduced by stocking ponds with egg-bearing females. Stocking density, as expressed by number of fertile eggs introduced, ranged from 74 to 326/ m². Ponds were harvested after culture periods ranging from 45 to 62 days. Juvenile number at harvest ranged from around 6000 to over 36 000, representing a mean of 63.2 juveniles per maternal survivor. Mean size at harvest ranged from 0.31 to 1.00 g, representing growth of 9.7 to 36.9 mg/day. Results suggest that managed pond production of juvenile redclaw is commercially viable at the production rates achieved, and that a considerable increase in productivity is possible with increased availability of shelter and improved zooplankton management techniques