Effects of temperature, algal food, feeding rate and density on the larval growth of the milk conch (Strombus costatus) in Mexico

Abstract Effects of temperature, algal food, feeding rate and larval density on the development and shell growth stage of conch veligers, Strombus costatus , were studied over a period of 30 days in laboratory cultures. Experiments were conducted at 24°C, 28°C, 32°C and 28 ± 2°C. After hatching, the veligers developed to metamorphosis within 26 days at 28°C, 28 days at 28 ± 2°C and 35 days at 24°C. Rearing was not successful at 32°C. Conch larvae were fed with the algae Isochrysis aff. galbana (Tahiti), Tetraselmis chuii and Isochrysis/Tetraselmis mix. The best rate of growth per day was 39.69 μm in Isochrysis/Tetraselmis mixed food. Experiments were conducted at 500, 1000, 2000, 3000, 4000, 5000 and 6000 Isochrysis aff. galbana cells larva −1 day −1 . The veligers showed an optimal growth at 3000 cells larva −1 day −1 . The conch veligers were reared at five larval densities: 100, 200, 300, 400, and 500 larvae/l, and showed an optimal growth at 100 larvae/l, while poorest growth was observed at 500 larvae/l.