The effect of temperature and conditioning interval on the spawning success of wild‐caught blacklip ( Haliotis rubra , Leach 1814) and greenlip ( H. laevigata , Donovan 1808) abalone

Wild‐caught blacklip ( Haliotis rubra , Leach 1814) and greenlip ( H. laevigata , Donovan 1808) abalone fed a formulated feed were held at 16 or 18°C for different conditioning intervals ranging from 114 to 235 days and induced to spawn using ultraviolet‐irradiated seawater. They were conditioned again for a second identical period before another induction. For H. rubra , mean spawning rate of both sexes was higher in groups held at 18°C than at 16°C, as was the repeat spawning rate. Conversely, animals held at 16°C produced significantly more gametes than those at 18°C. Egg production peaked in groups held at 16°C for ≥165 days. While both mean and total sperm production of H. rubra varied significantly, both figures were always high. Unlike H. rubra , the spawning rate, repeat spawning rate and gamete production of both sexes of H. laevigata were higher when cultured at 16°C than at 18°C. Egg production peaked in groups conditioned at 16°C for ≥212 days. Both mean and total sperm production by H. laevigata were much lower than for H. rubra . This study demonstrates that year‐round hatchery production of seedstock of both species is possible providing broodstock are held under favourable environmental conditions, preferably 16°C.