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The trawl ban in the Gulf of Castellammare (NW Sicily): a successful tool for the sustainable management of demersal fisheries. The Gulf of Castellammare (Tyrrhenian Sea, NW Sicily) has been subject since 1990 to a trawl ban that covers 200 km2, most of which on the continental shelf. The trawl ban was thought as a fisheries management measure to recover the depleted fish stocks in the area. The effectiveness of the ban was assessed through several research surveys carried out between 1985 and 2005, before and after the application of the trawl ban. The data collected after the ban were compared with (a) data from two control areas subject to trawling, and (b) data from the Gulf of Castellammare before the ban. The results showed a clear increase of fish biomass in the Gulf of Castellammare as a direct effect of protection. Only one species with a short life cycle and deep distribution like the pink shrimp Parapenaeus longirostris does not seem to be influenced by the limitation of the fishing effort. The other species, in particular the red mullet Mullus barbatus, showed a strong increase in density. The trawl ban confirms an effective measure of fish resource management. However, there is a need to keep a high level of control and enforcement of the ban and to ensure scientific monitoring to verify the effectiveness of this management tool.

This is the second collective paper issued in 2019, currently amalgamates new knowledge on the Mediterranean geographic distributions of 17 species from five phyla (six aliens, three cosmopolitans, two east Atlantic records and six natives). The acknowledged species were reported from ten countries, mentioned here from west to east: Spain: first report of the east Atlantic grouper Cephalopholis taeniops in the western Mediterranean and an inclusion of Pontarachna punctulum and Litarachna communis to the pontarachnid fauna of Spain; Morocco: first record of Solea senegalensis from the Moroccan Mediterranean coast; Algeria: a valid confirmation for the presence of Sardinella maderensis; Malta: a first record of the Red Sea stomatopod Erugosquilla massavensis; Italy: a rare observation of the crab Paragalene longicrura from Siciliy and a further integration of the alien brown shrimp Penaeus aztecus to the commercial catch in Sicily; Montenegro: a first record of the Lessepsian bigfin reef squid Sepioteuthis lessoniana from the Adriatic Sea; Turkey: northernmost documentation of the Mediterranean flatworm Prostheceraeus giesbrechtii in the Aegean Sea; Israel: a solid confirmation for the population establishment of both the alien rock shrimp Sicyonia lancifer and two species of angelfish, and a first and deepest record of the crystalline goby Odondebuenia balearica; Lebanon: first record of the jellyfish Pelagia noctiluca; Syria: first records of the crown jellyfish Nausithoe punctate and the smallscale codlet Bregmaceros nectabanus., peer-reviewed

This study assesses the effects of a trawling ban on the diet and trophodynamics of the hake Merluccius merluccius by comparing stomach contents and stable isotopes (δ15N and δ13C) in two trawled gulfs and one untrawled gulf in northern Sicily (western Mediterranean). Comparisons were made for three size classes of hake encompassing 60 to 410 mm total length. Fish were collected from 50 to 200 m depth on muddy bottoms. The diets of hake of small and medium size were similar overall but more selective in the untrawled gulf. Greater differences were detected between the diets of larger specimens from trawled and untrawled areas. In the untrawled gulf large hake mainly preyed on clupeoid fish, while in the trawled gulfs other fish prey were found in the stomach contents. δ15N values of hake did not vary significantly between trawled and untrawled areas, while there was a clear effect of size, with larger individuals being significantly more enriched than juveniles. Conversely, δ13C values were generally more depleted for individuals collected in the untrawled area, suggesting a more pelagic source of carbon. The results from the mixing model agree fairly well with the known feeding habits found for each size class in each area., Este estudio evaluó los efectos de la pesca de arrastre comercial en la dieta y la trofodinámica de la merluza mediterránea, Merluccius merluccius, mediante la comparación de sus contenidos estomacales y de la composición isotópica (δ15N y δ13C) en dos golfos donde está permitida la pesca de arrastre y en uno donde está prohibida, en el norte de Sicilia (Mediterráneo Occidental). Las comparaciones se hicieron para tres clases de talla que abarca la merluza entre 60 y 410 mm de longitud total. Los peces fueron recolectados en los fondos fangosos de la plataforma continental de 50 a 200 m de profundidad. Los hábitos alimenticios de las merluzas pequeñas y medianas eran similares, pero más selectivo en el golfo donde la pesca está prohibida. Las mayores diferencias se produjeron en la dieta de los especímenes más grandes comparando los golfos arrastrados con el golfo protegido. En el área protegida las merluzas grandes cazaban sobre todo en clupeidos y engráulidos, mientras que otros peces se encuentran en el contenido estomacal de M. merluccius de las áreas de pesca. Los valores de δ15N de la merluza no variaron significativamente entre las áreas protegidas y no protegidas, mientras que hubo un efecto claro de la talla: valores más alto, se han observado en los animales más grandes. Por el contrario los valores de δ13C fueron en general más empobrecidos (más negativos) en los ejemplares recolectados en el área protegida, esto indica una fuente más planctónica de carbono. Los resultados de los mixing models concuerdan bastante bien con los hábitos de alimentación observados para cada clase de talla y en cada área.

The present study intends to update a previous study (EC MED92/011) in order to (i) assess the effect of an eight-year trawl ban on the demersal resources (over trawlable and non-trawlable bottoms) in the Gulf of Castellammare, and (ii) investigate how these resources are now being exploited by the small-scale fishery, as well as the extent of any social or economic gain arising as a result of the trawl ban. The study is made of two parts: A) biological section, and B) socio-economic section, THE FULL VERSION OF THIS REPORT SHOULD BE REQUESTED TO THE AUTHOR (CARLO PIPITONE: CARLO.PIPITONE@CNR.IT) WITH PROPER JUSTIFICATION.