Growth and spawning of hatcheryreared Chinese white prawn Penaeus (Fenneropenaeus) chinensis released in the Ariake Sea, Japan

Abstract

Growth and reproduction of hatchery-reared Chinese white prawn Penaeus chinensis released in the Ariake Sea, Japan, were examined. Chinese white prawn grew rapidly, reaching a body length of 154 mm in males and 198 mm in females by November (219-229 days after hatching). Maximum body length of sampled individuals was 164 mm in males and 223 mm in females. Growth curve of the Chinese white prawn was fitted to the Pitcher and MacDonald's formula, L_t=155.0{1-e^{2.925sin[2π(t-16.151)/365]-0.0623(t-10.712)}} for males and the logistic curve, L_t=200.3/[1+e^{(1.985-0.034t)}] for females (where L_t is the body length t days after release and t is the number of days after release). Females reached sexual maturity in late February and spawning occurred until April. Minimum size at ripe and spawned stages was 189 mm and 193 mm body length, respectively.