摘要：As production of seabass and sea bream has expanded in the Mediterranean over the past decade, prices for each have fallen dramatically. The lower revenues that have resulted have forced some once-profitable producers out of business and made entry into the market by new producers much more difficult. This reality must be taken into account in formulating any successful national or enterprise-level development plan based on production of these “old” species. Introduction of “new” commercial species is one possible response, and several fish and invertebrates have received attention in this regard. Of the invertebrates, one echinoderm, the sea urchin Paracentrotus lividus, and two molluscs, the cuttlefish Sepia officinalis and the common octopus Octopus vulgaris, appear to have sufficient potential for Croatian mariculture to warrant closer examination of their advantages and disadvantages, and to invest the capital and effort on applied research to overcome the latter. In the case of the cephalopods, full commercialization of both cuttlefish and octopus is limited by availability of an economical crustacean feed for early stages. Further, although culture systems for cuttlefish are well established, a octopus grow-out system that satisfactorily reduces the animal’s natural agonistic tendencies while permitting unencumbered routine feeding and maintenance has yet to be identified. Commercial sea urchin cultivation is limited by several factors, including an efficient juvenile feed; but the quickest route to sea urchin commercialization is out-of-season gonad (roe) enhancement of natural stock, analogous to the way in which the successful Croatian tuna-ranching industry operates. The success of this ‘bulking’ process depends upon availability of an effective diet and a containment system that addresses the peculiarities of sea urchin behavior in captivity. Of the three species examined briefly here, cuttlefish can be commercialized the fastest. The next step in cuttlefish development is to operate pilot-scale production trials to evaluate its economic feasibility under Croatian conditions. ‘Bulking’ of sea urchin offers the next most promising new commercial opportunity and merits feed trials using at least one of several published feed formulations, perhaps followed by a diet of local macroalgae to ‘polish’ the product’s taste to market standards. Octopus now appears to be the least ready of the three. A positive step in its development in Croatia is to transfer the latest techniques on paralarval rearing, the better to be prepared to take full commercial advantage of further advances in this area as they become available.
