CONTROLLED SPAWNING OF F1 HYBRID STRIPED BASS (Morone saxatilis X M. chrysops) AND REARING OF F2 PROGENY1

Abstract

ABSTRACTF1 hybrid bass (striped bass female x white bass male) were matured under controlled photoperiod and temperature regimes. These fish were spawned, using human chorionic gonadotropin (HCG), about 3 months earlier than normally occurs for striped bass in South Carolina. This was accomplished by compressing the natural annual cycle to 9 months. Under controlled conditions, fish previously spawned were reconditioned and respawned in 9 months. When injected with HCG, paired male and female F1 hybrids were able to spawn in tanks.Hatch rate was low (10%) in the F1 x F1 cross. Further, the F2 larvae exhibited a high degree of growth variation and cannibalism which is common among striped bass larvae. Larval F2 hybrids, stocked at an initial density of 73,510 fish/m3, grew to a mean size of 41.9 mm TL (range 32.0–52.0 mm) in 46 days. Juvenile F2 hybrids, mean weight 12.8 g, were stocked in a controlled recirculating water system at a density of 31/m3. During 189 days, these fish grew to a mean size of 222 g and exhibited a survival of 92.5%.