Size dependent variation in optimum growth temperature of red abalone (Haliotis rufescens)

Six size groups of red abalone Haliotis rufescens (geometric mean shell lengths: 21, 25, 33, 66, 81 and 98 mm) were reared on a macroalgal diet for 4 months at seven different temperatures between 11 and 22 degreesC. The results demonstrate that red abalone exhibit size dependent variation in growth potential and temperature optimum for growth. The maximum growth rate was found to have a skewed, third degree polynomial relationship with shell length, reaching a maximum of 111 mum day(-1) at 38 mm shell length. The temperature optimum for growth was found to have a symmetrical, concave relationship with shell length from 16 mm to maturity, reaching a peak of 17.8 degreesC at 44 torn shell length. The minimum grow-out time from spat to market size on an optimum temperature regime was predicted less than 2 years. The results from the present study could contribute to an increase in the potential yield from landbased abalone farming. (C) 2003 Elsevier Science B.V All rights reserved.