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Non age-structured production model analyses of North Atlantic swordfish have been used in addition to age structured virtual population analyses by ICCAT's SCRS to evaluate the status of the resource and to provide a basis for management advice. Production models require a standardized index of relative abundance in terms of biomass. The fleets combined standardized biomass index of abundance developed for the 2006 ICCAT-SCRS meetings for north Atlantic swordfish was revised and updated with data through 2008. Generalized Linear Modeling (GLM) procedures were used to standardize swordfish catch (biomass) and nominal effort (number of hooks) data from longline fleets from the United States, Spain, Canada, Japan, Morocco and Portugal. As in past analyses, main effects included: year, area, quarter, a nation-operation variable accounting for gear and operational differences thought to influence swordfish catchability, a target variable to account for trips where tunas and/or sharks were predominant in the catch or potentially also targeted, and interaction terms for year* area 0

The northern coasts of the Alboran Sea are known to have thrived from past artisanal fisheries that exploited the early life stages of fishes. This was mainly carried out by a suite of different fishing gears dating back to the eighteenth century to the end of the twentieth century (Sañez-Reguart 1791–1795 reprint 1988; Rodríguez Santamaría 1923). These fishery studies provide detailed descriptions of the fishing gears employed by fishermen exploiting the Iberian Peninsula coasts and a general account of the targeted species and their associated catches. In the Andalusian coasts of the Alboran Sea, beach seines called boliches were among the most common, targeting on sardines, anchovies, and a number of other fish species, as bonitos and tunas that preyed on small pelagic shoals (Fig. 13.1).

We conducted a review of small pelagic fisheries of anchovy (Engraulis encrasicolus) and sardine (Sardina pilchardus) in the northern Alboran Sea (western Mediterranean Sea). This overview focuses on a long historical series of landings (from the 1940s to the present), the number of fishery vessels (from the 1970s onward), the fishery effort during the last decade, and acoustic assessment. Sardine and anchovy landings since the 1940s show very strong oscillations. The highest landings correspond to periods when the Spanish fleet could fish in the southern part of the Alboran Sea: before 1959, Morocco was not yet an independent country and later in the 1980s due to fishing agreements with that country. The fleet has been decreasing, since 1973 till nowadays; in 2017 the fleet only represents 24% of that of the year 1973. Currently, landings are low and correspond only to fishing in the northern waters of the Alboran Sea., SI