Suspended culture of doughboy scallops Mimachlamys asperrima (Lamarck).

To evaluate the effects of suspended culture on the wet meat weights, reproductive condition and fecundity of doughboy scallops Mimachlamys asperrima, scallops held either in suspended cages or collected from wild stocks on the sea bed were compared over a year. Changes in gonosomatic index (GSI) and macroscopic staging of gonads were similar in both populations; however, after one month, soft body, muscle and gonad weights were heavier in suspended scallops and, with the exception of gonad weight in early summer, remained heavier throughout the year. Fecundity following serotonin-induced spawning of suspended Mimachlamys asperrima was on average almost twice that of similar sized scallops grown on the sea bed (1.58 and 0.84 million eggs/female, respectively). Suspended scallops surpassed all previous maxima for tissue weights, GSI and fecundity recorded for wild Jervis Bay Mimachlamys asperrima. This indicated that farmers could obtain greater meat yields from suspended rather than reseeded or wild Mimachlamys asperrima and that broodstock to be used in hatcheries may be best obtained from suspended culture.