Indoor artificial breeding and juvenile nursing of Cherax quadricarinatus

Studies on culture of parent crayf ish, winter rearing, hatching and indoor artificial breeding of the red crayfish ( Cherax quadricarinatus ) were carried out from 1996 to 1998 in the northern region of Zhejiang Province. Results showed that the red crayfish is appropriate for farming and breeding in Zhejiang Province. In the northern region of Zhejiang Province, the juvenile crayfish ( sizes of 2. 8- 4. 9g) can grow to sexual maturity and the survival rate in pond was over 70% during the winter seasons because of warm water supply from a local power plant. In February, when the water temperature went up to 20 .. , the parent red crayf ish began to copulate and breed, but the epacme were observed in April to June. The red crayfish can spawn four times a year, but only the first and the second hatches are useful for juvenile nursing purpose. A female brood normally ovulate 400- 500 eggs, but the spawning rate of the population in a pond is commonly high. The red crayfish develops from fertilized egg to juveniles directly, which is quite different from crabs and shrimps. The hatch need stay on the pleopod of the female brood for 7 to 10 days, and then begin to leave and live on extraneous foods. The juveniles do not need live food absolutely. A formulated feed has been developed successfully for nursery stage juvenile. Temperature regulation and intensive management during the indoor nursery stage are very important for juvenile nursing success, and the survival rate can reach up to 60%.