Several species of sea urchins are now being cultivated for commercial purposes and with the continued increased demand for sea urchin gonads as a food product, new species are being assessed for their aquaculture and market potential. This study focussed on establishing protocols for the production of common sea urchin Echinus esculentus larvae and juveniles to assess its potential as an echinoculture species. Two trials were carried out, the first trial evaluated the influence of three microalgal diets (D=Dunaliella tertiolecta only, mixed D/P=D. tertiolecta plus Phaeodactylum tricornutum and P=P tricornutum only) on larval morphology. Larval length, width, post-oral arm length and rudiment length were significantly effected by diet. Diets D and D/P prompted more rapid metamorphosis. In the second trial, the effects of different rations of D. tertiolecta were tested. The food ration, standard ration (SR; 1000, 3000, and 5000 cells ml(-1)) and high ration (HR; 3000, 9000, and 15,000 cells ml(-1)) were increased as the larvae acquired the 3rd and 4th pair of larval arms. Larvae fed the SR were significantly larger (longer and wider) and had significantly longer rudiments than those in the HR treatment. The number of larvae metamorphosing and settling onto substrates was significantly higher in treatment SR compared to HR. Optimising the larval diet shortened the larval stage from 21-23 days in the first trial to 16 days in the second trial. The maximum percentage of metamorphosing individuals which survived to post-larvae or juveniles (10 days after they were first judged competent to settle) was 46.6%, suggesting E. esculentus is a viable aquaculture candidate. (C) 2003 Elsevier Science B.V. All rights reserved.
- ARTIFICIAL DIETS
- Marine & Freshwater Biology