The abalone Haliotis diversicolor (Reeve) or 'tokobushi' is being cultured in Kagoshima, southern Japan for stock enhancement of ¢shing grounds. However, with decreasing catches from the wild some ¢shermen's group may eventually resort to rearing tokobushi until of marketable size. Growth experiments of tokobushi fed macroalgae in £oating net cage and plastic tanks were conducted to evaluate the in£uence of culture system, macroalgal food, age and water temperature on their culture. In £oating net cage, marketable sizes were obtained at the age of 457^822-day old (15^27-month old) with highest growth rate of 2.36% g day À1 and 0.21mm day À1 . One advantage of the plastic tank culture system was that the tokobushi shell remained clean throughout the culture period. Macroalgal food a¡ected the growth rate; Sargassum fusiforme (Setchell)-and Ulva pertusa (Kjellman)-fed tokobushi were better than Meristotheca papulosa (Montagne)-fed. Further, 1-year-old tokobushi had better growth performance and condition index than the 2-year-old cohort, and growth rates were higher at17 1C than at12 1C. These ¢ndings should help tokobushi farmers design their mariculture scheme considering both economic and environmental aspects.

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