Artículo de publicación ISISome 290 species of squids comprise the order Teuthida that belongs to the molluscan Class Cephalopoda. Of these, about 30-40 squid species have substantial commercial importance around the world. Squid fisheries make a rather small contribution to world landings from capture fisheries relative to that of fish, but the proportion has increased steadily over the last decade, with some signs of recent leveling off. The present overview describes all substantial squid fisheries around the globe. The main ecological and biological features of exploited stocks, and key aspects of fisheries management are presented for each commercial species of squid worldwide. The history and fishing methods used in squid fisheries are also described. Special attention has been paid to interactions between squid fisheries and marine ecosystems including the effects of fishing gear, the role of squid in ecosystem change induced by overfishing on groundfish, and ecosystem-based fishery management

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In order to obtain basic information on the population structure of Japanese sea bass Lateolabrax japonicus, four sample lots were collected from coastal waters of Seto Inland Sea (Akashi, Murotsu, and Nandan) and from Japan Sea (Kasumi) in Hyogo Prefecture, Japan. Seventy-one to eighty speci mens from each locality were examined for the screening of polymorphism among 12 loci in 10 en zymes. Being fitted for Hardy-Weinberg equilibrium, it was suggested that each lot was derived from simple Mendelian population. The proportion of polymorphic loci ranged between 0.55-0.67 and the expected heterozygosity (He) were between 0.172-0.199. Considering these much higher values com pared with some other marine fishes, the high genetic variability should be retained in this species. The differentiations among localities were tested by chi-square values for heterogeneity. In MPI-1 * locus, highly significant difference (p<0.001) was detected in the case of Kasumi vs. each locality of Seto Inland Sea. The D values (0.0014-0.0082) were high, especially in the cases related with Kasumi (0.0054-0.0082). These results indicate the independence of the subpopulation of Kasumi from the others. Among the Inland lots, we could not get enough information about the existence of subpopula tion except for the cases of significant difference in sIDDH*.

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