Natural spawning and mass larviculture of black porgy Acanthopagrus schlegeli in captivity in Taiwan

Abstract

The black porgy Acanthopagrus schlegeli is one of the most important marine fish cultured in Taiwan. Wild-caught broodstock were spawned naturally in captivity at water temperatures of 19-26 C in 1989 and 1990. Females produced 352,000 to 957,000 eggs per female during the spawning period. The hatched larvae were reared in 45-m3 rectangular cement tanks and fed initially on rotifers, Brachionus plicatilis, followed by Artemia nauplii, and finally weaned onto an artificial diet. Larviculture trials to 40 d produced juveniles of 13.1-14.2 mm average total length, at a survival rate ranging from 18.3 to 74.8%. Lordotic deformation was observed in the juvenile stage. However, when an oil skimmer was used to remove the oil film on the water surface, the incidence of lordosis was reduced from 14.4 to 6.1%. High mortality of the larvae occurred during the initial 10-15 d after hatching and cannibalism was observed when larvae reached 7 mm total length. Juveniles grew to size of 83.7-101.4 mm total length with survival rate of 27.9-28.2% in 100 d. The results indicate that the present technique can be used for mass seed production of black porgy.