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Marine species from the Egadi Islands         175

              Favignana and Marettimo, to characterize the most utilized gears and the species caught most
              often. From these, we selected the “target species” for our analyses to qualify the fish products
              of the Egadi Islands. The target species, Scorpaena porcus (Linnaeus, 1758), Scorpaena scrofa
              (Linnaeus, 1758), Palinurus elephas (Fabricius, 1787), and Sepia officinalis (Linnaeus, 1758),
              were caught in the typical areas used by local fishermen of Egadi Islands, by trammel net,
              during the months of June and July 2003.
                The samples were kept cold until they were transferred to the laboratory for analysis on fresh
              products. In each month, eight samples of each species were weighed, gutted, and filleted, and
              homogeneous samples were prepared (two replicates for each species to be used for analysis).
              The live weight of Scorpaena porcus was 250–350 g, for Scorpaena scrofa 350–450 g, for
              Palinurus elephas 1000–1700 g, and for Sepia officinalis 400–600 g.
                Each sample was analysed in duplicate for moisture, ash, protein, total lipid content, and
              for fatty-acid percentage distribution. The moisture and ash content was determined according
              toAOAC official methods [8, 9]; protein content was determined by the Kjeldhal method [10];
              for the determination of total lipids, the minced samples were extracted with a mixture of
              chloroform/methanol (2:1, v/v) according to the Folk method [11], modified by Ways and
              Hanahan [12]. Weighed portions (around 15 mg) of the total lipid were converted to fatty-acid
              methyl esters (FAMEs) [13] by direct transesterification with 1% sulphuric acid/methanol
  Downloaded At: 20:22 7 January 2011  (FID). Separations were realized with a 30 m × 0.32 mm i.d. fused silica capillary column
              under reflux and in an argon atmosphere. FAMEs were analysed [14] by gas chromatography
              with a DANI 1000 gas chromatograph equipped with a hydrogen flame ionization detector

              Omegawax 320 (Supelco, Italy) with a 0.25 mm film thickness. The individual FAMEs were
              identified by comparison with the retention times of standard mixtures (Supelco PUFAs 1–2
              and Menhanden Oil Test Mix).
                The saturated/unsaturated fatty-acid ratio (S/P), atherogenicity index (AI), and thrombo-
              genicity index (TI) were calculated according to Ulbricht and Southgate [15].
                The SPSS 11.5 (2002) software package (SPSS, Chicago, IL) was used for statistical treat-
              ment of the data.A one-way analysis of variance (ANOVA) was applied to the data to determine
              the presence of significant differences (Duncan test, significant level P< 0.05) in the gross
              composition and fatty-acid distribution among the four species, and for each species between
              the June and July samples.

              3. Results and discussion

              The fishing activity practised by fishermen of the Egadi Islands Marine Protected Area (MPA)
              was characterized principally by small boats that practise artisan fishing, alternating the use
              of more gears during the year. During the summer period, this activity is supported by fishing
              tourism, which has undergone a development in the last year and is increasing, thanks to the
              presence of the MPA.
                The Favignana fishery had the highest number of boats, with 30 boats in service, followed
              by Marettimo’s fishery, which has 11 boats and, finally, by the Levanzo fishery with only
              two boats.
                The main fishing activity is carried out using the trammel net (91%), whereas the use of
              gillnets (49%), surrounding nets (33%) and entangling nets (26%) is limited to those seasonal
              periods suitable for the capture of species like Boops boops, Maena sp., Trachurus sp., Oblada
              melanura, Scomber japonicus, Gymnammodites cicerellus, and Belone belone gracilis. The
              bottom trawl is used very little. The use of pots for species such as Palinurus elephas has
              been greatly reduced (2%). Local fishermen said that they were very widespread until 10 yr
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