Untitled - CNR

Marine research at CNRFigure 2: Integrated “surface map” of the roughness index derived from fastenings andship wrecks in the Strait of Sicily; ship wrecks are superimposed (black dots).Pescato – ITPP). In fact, IAMC Mazara hascarried out, almost without interruption,two trawl surveys (for a total of over 4000hauls), one in late spring (international surveyMedits, since 1994) and the secondin autumn (national survey Grund, since1985); the experimental design is randomdepth stratified (10,880 m), in the GFCM’sarea GSA 16, broadly corresponding to theItalian half of the Strait of Sicily, and hasa framework agreement with the MalteseMCFS; altogether the regularly monitoredarea is 57,500 km 2 (over a total of 257,500km 2 for the entire Strait).First, rough, hard to trawl or untrawlablepatches has been recovered (Table 1),based on the occurrence of not valid hauls(interrupted before scheduled time or withevidence of gear malfunctioning), causedby both natural (cliffs, rocky outcrops,boulders and coralligenous habitats) orman induced (shipwrecks, “mazzare”, etc.)graspings, which make fishing dangerousfor the gear, during the Medits and Grundscientific surveys [1].Thereafter, data on all the known shipwrecks occurring in the Strait of Sicilyhave been gathered from different sources,both published [2] and unpublished; altogether,about 1300 records were collected,allowing the identification of 457 differentship wrecks, which were imported in a GISdatabase (pixels of 1x1 nm). Since naturallyuntrawlable areas could have a synergiceffect with the man made obstaclesto trawling, a joint “roughness index” has1925