Comparison of biological characteristics of commercially important cephalopods in different areas of the Adriatic Sea (Central Mediterranean)

Cephalopods are important fisheries resources in the Adriatic Sea (Central Mediterranean). They are caught using different kinds of fishing gears, primarily bottom trawl nets, and they contribute to a large fraction of commercial landings in the region. The Adriatic Sea is one of the largest and best defined areas of the occurrence of shared stocks in the Mediterranean and cephalopod stocks are exploited by fishing fleets of several countries: Albania, Croatia, Italy, Montenegro and Slovenia. Among cephalopods, Eledone cirrhosa, Illex coindetti, Loligo vulgaris and Sepia officinalis are regarded as the main fisheries target species taking into account both the total capture production and the market prize. In the present study the main biological characteristics of these species in terms of distribution, size range, length frequency distribution, length-weight relationship, sex ratio and size at maturity are described for the Northern and Central and for the Southern Adriatic Sea using both fishery dependent (commercial landings) and fishery independent data (bottom trawl surveys). The biological parameters are compared and differences among areas are pointed out. The results are discussed in the light of differences in environmental factors characterising each part of the Adriatic basin.