A review: Adriatic groupers – Status of natural populations and breeding perspectives

Abstract

       Short review about status of natural populations offour grouper species that live in the Adriatic is presented. All groupers belong to genus Epinephelus. There are: dusky grouper, Epinephelus marginatus, white grouper, Epinephelus aeneus, goldblotch grouper, Epinephelus costae and dog­tooth grouper, Epinephelus caninus.

      The main biological characteristics, which influence the Adriatic groupers populations, are tropical origin and protogynic hermaphroditisms. As a tropical species living in the Adriatic on the edge of their distribution, they do not exibit many of their characteristics, such as good growth rate and spawning during few months period. Protogynic hermaphroditism as a mode of reproduction is one of problems in our conditions, because elimination of male from population could influence whole spawning.

      Among the four species only dusky grouper is of interest for Adriatic fishery. Mainly, because other three species are relatively rare. The yearly catch of dusky grouper in the Adriatic is estimat­ed around 30 tons.

      Presently, the three species: dusky, goldblotch and white grouper are objects of research on introduction in aquaculture. Dusky grouper is investigated in Croatia and Italy, goldblotch grouper in Croatia and white grouper in Israel. The main achievements of this research in our Laboratory are successfully induced spawning, description of early stages, and experiments on larval rearing. Furthermore, we made a sex-reversal of smaller females and immature fish and obtained small fer­tile males. Future research will concentrate on larval feeding and production of juveniles for growth experiments.