DISTRIBUTION MODEL AND ASSOCIATION IN 3 PELAGIC CONGENERIC SPECIES (TRACHURUS SPP) PRESENT IN THE IBERIC MEDITERRANEAN-SEA

The total number of fish species catalogued for the Iberic Mediterrane an Sea (Balearic and Alboran Sea), consists of 519 which are found thr oughout the year or are seasonal in the water column and at the bottom ranging between 0 and 1050 meters deep. The above mentioned depth ran ge is where the three congeneric species belonging to the family Caran gidae (Trachurus mediterraneus, Trachurus picturatus and Trachurus tra churus), considered as middle-sized pelagic fishes, develop their resp ective life cycles. These species may overlap in an interval of the wa ter column. This overlapping contributes to obscure their habits in su ch a way that, from the statistical and fishery point of view, they ar e usually considered as a single unit (Trachurus spp.), thus ignoring their true distributional pattern. In fact, each of the Trachurus spec ies is very precisely related with a group of fish acting as indicator s of a particular niche. This diversity makes the differentiation amon g habitats a way to distinguish the different Trachurus species, and t hus attenuates any kind of intercongeneric competition or rivalry.