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A seguito del violento rilascio di gas, verifica-tosi nel 2002 e 2003, nell'area prospiciente gli isolotti a est dell'isola vulcanica di Panarea, sono state condotte nume-rose ricerche per comprendere l'origine, la natura e gli effetti di queste emissioni. Tali ricerche hanno evidenziato vari punti di rilascio di gas e fluidi idrotermali ricchi di CO2 nel-l'area di mare a est di Panarea e hanno prodotto diverse stime della CO2 totale rilasciata dal sistema sottomarino a partire dal post-glaciale ad oggi. Alla luce di questo, l'ISMAR-CNR e l'ISPRA hanno condotto delle ricerche specifiche tra il 2013 e il 2015 per caratterizzare il campo idrotermale sommerso compreso tra l'isola di Panarea e l'isolotto di Basiluzzo (NE di Panarea), dal punto di vista morfologico, biologico e chimico-fisico, in particolare per ciò che riguarda i flussi bentici diffusi. Le campagne ocea-nografiche hanno consentito di individuare e caratterizzare tre aree con intensa attività idrotermale.

A seguito del violento rilascio di gas, verificatosi nel 2002 e 2003, nell'area prospiciente gli isolotti a est dell'Isola vulcanica di Panarea, sono state condotte numerose ricerche per comprendere l'origine, la natura e gli effetti di queste emissioni. Tali ricerche hanno evidenziato vari punti di rilascio di gas e fluidi idrotermali ricchi di CO2 nell'area di mare a est di Panarea e hanno prodotto diverse stime della CO2 totale rilasciata dal sistema sottomarino a partire dal post-glaciale ad oggi. Alla luce di questo, l'ISMAR-CNR e l'ISPRA hanno condotto delle ricerche specifiche tra il 2013 e il 2015 per caratterizzare il campo idrotermale sommerso compreso tra l'isola di Panarea e l'isolotto di Basiluzzo (NE di Panarea), dal punto di vista morfologico, biologico e chimico- fisico, in particolare per ciò che riguarda i flussi bentici diffusi. Le campagne oceanografiche hanno consentito di individuare e caratterizzare tre aree con intensa attività idrotermale. La prima area, situata a Sud-Est dell'isola di Panarea (Secca dei Pesci), è caratterizzata da un'intensa attività esalativa di fluidi acidi, ricchi di DIC, a temperatura ambiente ma con deboli contenuti in metalli. La seconda area, scoperta nel 2015, situata ai piedi della scarpata a Nord-Est dell'isola di Panarea, è stata denominata Smoking Land per la presenza di circa 200 camini idrotermali di dimensioni consistenti (1-4 m di altezza; circa 4 m in media di diametro di base), in parte attivi e in parte quiescenti. L'ultima area, situata a Nord-Est degli isolotti DBLP, è caratterizzata da depressioni circolari, anche esse in parte attive e in parte inattive. In queste ultime due aree, le misure di flussi bentici disciolti hanno evidenziato un andamento a macchia di leopardo con rilascio di fluidi acidi, a temperatura ambiente, ricchi di DIC, Fe e altri metalli (Mn, Zn, Al). Queste due aree sono localizzate ai margini di un avvallamento allungato in direzione OSO-ENE. Esse sono il risultato di una circolazione idrotermale con risalita, lungo faglie distensive, di gas di origine vulcanica mescolati ad acqua di mare penetrata nel sottofondo marino. Adiacenti alle aree attive sono presenti aree inattive, cariche di gas in sovrappressione per la presenza di uno strato superficiale di ossidi e idrossidi di Fe che ne impedisce la fuoriuscita, e aree quiescenti per una degassificazione già avvenuta. Da questo assetto deriva la necessità di un continuo monitoraggio atto a prevedere possibili future situazioni di pericolo per le aree circostanti.

Il Golfo di Castellammare (Mar Tirreno, Sicilia nord-occidentale) è sottoposto dal 1990 a un divieto di pesca a strascico che copre gran parte della piattaforma continentale per circa 200 km2. L'efficacia del divieto come misura di gestione della pesca finalizzata al recupero degli stock ittici è stata valutata attraverso numerose campagne di ricerca effettuate fra il 1985 e il 2005, prima e dopo l'applicazione del divieto. I dati raccolti dopo il divieto sono stati confrontati con dati provenienti da due aree di controllo sulla costa settentrionale della Sicilia soggette a pesca a strascico e con dati raccolti prima del divieto. I risultati ottenuti mostrano un chiaro aumento della biomassa ittica nel Golfo di Castellammare come conseguenza della protezione. Una specie a breve ciclo vitale e a distribuzione profonda come il gambero rosa Parapenaeus longirostris non sembra essere influenzata dal divieto. Le altre, in particolare la triglia di fango Mullus barbatus hanno mostrato un forte aumento di densità. Il divieto di strascico si conferma una misura efficace di gestione sostenibile delle risorse ittiche demersali. Vengono inoltre evidenziati i problemi legati al ridotto controllo sull'applicazione del divieto e la necessità di un monitoraggio scientifico per verificare l'efficacia della misura di gestione.

Until 2014, the management of invasive alien species has been poorly addressed in Europe. Recently, the Regulation 1143/14 on invasive alien species (IAS) was issued by the European Community. A first list of "IAS of Union Concern" was presented in 2016 and subsequently updated in 2017. The species included in that list are subjected to a number of commercial restrictions, and EU member states are required to control or eradicate them. The inclusion of an IAS in this list is based on the results of a risk-assessment procedure. At present, this list contains 49 IAS, none of which marine. Member states can decide either to adopt the EU list as it is, or to integrate it with additional "IAS of national concern". Italy has opted for the second way and is currently developing its own national list, which may eventually include marine IAS. Italy is a major "first hub" for marine introductions in the Mediterranean Sea, with over 200 multicellular marine alien species reported so far. Italy, with its central position in the Mediterranean Sea, shares several species with the Western European countries, carried by ships or with shellfish stocks, as well as a number of Indo-Pacific species with the Eastern Mediterranean countries, entered through the Suez Canal. Therefore, the roadmap that Italy is currently tracing towards the possible inclusion of marine species in the list of IAS to be managed and controlled, is also relevant for other European and Mediterranean countries. This presentation will show how the process has been organized and conducted, and the preliminary outcomes

Si riportano i primi risultati dell'esercizio di prioritizzazione delle specie aliene dei mari italiani condotto per conto di ISPRA dagli esperti dei singoli gruppi tassonomici iscritti al Gruppo Alloctone della Società Italiana di Biologia Marina

Macro- and meiofauna associated with Posidonia oceanica meadows colonized by the invasive alga Caulerpa taxifolia var. distichophylla (Caulerpales) in southern Sicily were analyzed and compared with assemblages of control meadows from the same area. Independently from the degree of invasion (severe or partial), the affected macrofaunal assemblages significantly differed from the controls with the former ones characterized by an increase of molluscs and polychaetes and the decrease of crustaceans. Meiofaunal assemblages showed contrasting results being affected by severe algal invasion but not significantly differing from control assemblages under partial invasion conditions, suggesting some tolerance to the invader.

A new population of the protected species Pholas dactylus was discovered for the first time in the central Mediterranean Sea, more precisely in the southern coast of Sicily. Living populations of P. dactylus have been previously reported, in the Mediterranean Sea, only from the Greek Seas, the Balearic Islands, Turkey, Lebanon and the Italian coast of central Adriatic Sea. The common piddock was observed in five sites characterized by grey-white calcareous marl rocks with a mean density of 1348 ± 672 m-2 and a mean length of 36.8 ± 22.8 mm. A number of other protected species were also found in the same area, including the endolithic bivalve Lithophaga lithophaga, the large bivalve Pinna nobilis, the brown alga Cystoseira amentacea and the Mediterranean seagrass Posidonia oceanica. The last two species form associations that are considered priority habitats according to the Annex I of the SPA/BD Protocol of the Barcelona Convention. Considering the environmental importance of this rare ecosystem, characterized by protected species and habitats, specific conservation strategies should be adopted in the area. Finally, it would be appropriate to introduce the 'facies with P. dactylus' within the 'biocenosis of infralittoral algae' as a priority habitat of the Annex I of the SPA/BD Protocol.

Macro- and meiofauna associated with Posidonia oceanica meadows colonized by the invasive alga Caulerpa taxifolia var. distichophylla (Caulerpales) in southern Sicily were analyzed and compared with assemblages of control meadows from the same area. Independently from the degree of invasion (severe or partial), the affected macrofaunal assemblages significantly differed from the controls with the former ones characterized by an increase of molluscs and polychaetes and the decrease of crustaceans. Meiofaunal assemblages showed contrasting results being affected by severe algal invasion but not significantly differing from control assemblages under partial invasion conditions, suggesting some tolerance to the invader.

Summary The diet of juvenile bluefin tuna (Thunnus thynnus) caught 2 to 8 miles off NE Sicily was investigated in order to improve knowledge of the species’ early life history. From 1998 to 2000, 107 specimens ranging from 63 to 495 mm (total length) were fished between July and November. Fishes were caught by trolling line or purse seine in a Fish Aggregating Devices (FADs) area 2 to 8 miles offshore and as by-catch of the purse-seine sardine fishery 2 to 4 miles offshore. Most frequently found items in the T. thynnus stomachs were fishes (84.5%), crustaceans (54.6%) and cephalopods (50.5%). The largest contribution in weight was provided by cephalopods (47.3%) and fishes (46.5%), while the most abundant items were fishes (51%), cephalopods (27.2%) and crustaceans (21.1%). These results suggest that young-of-the-year tuna have an essentially piscivorous diet, although invertebrate prey provide a substantial contribution to the food array. Prey show little relationship with FADs, although one prey species (blue runner, Caranx crysos) is associated with FADs in the Mediterranean.

A consistent living population of Panopea glycimeris (von Born, 1778) was documented underwater along the eastern coast of Sicily. Twenty specimens were counted over an area of 1000 m(2), with an estimated total population of less than 300 individuals. The morphometric measurements of an adult specimen captured are provided. Proposals to adopt protection measures for this species are discussed.

This study was aimed at identifying the food web of the red mullet, Mullus barbatus in order to understand how it is affected by trawling disturbance. To achieve this objective: a) the main features of the red mullet habitat were investigated; b) the food web of this habitat was studied in two no-trawl areas and in two areas open to trawling. The working hypothesis is that trawling affects the biochemistry of the sediment and the trophic structure of the benthic assemblage. It was predicted: a) less biomass, smaller size and higher production rate in the benthic assemblages of protected gulfs; b) higher average trophic level for both the red mullet and its predators in protected gulfs; c) a diet shift driven by the mechanical disturbance of trawling. The results achieved confirmed our hypotheses and allowed us to characterize for the first time the trophic web structure in the red mullet habitat in the study area. Results also allowed us to compare the trophic level of red mullet of different sizes using two independent techniques, stable isotopes of nitrogen and gut contents. The average trophic level of the red mullet was higher and the energy consumption per unit of biomass larger in the protected gulfs. Species with a trophic level higher than the red mullet and therefore its potential predators were few and the most important were the white grouper, Epinephelus aeneus, the pandora, Pagellus erythrinus and the common torpedo, Torpedo torpedo.

Levels of four (Hg, Cd, Pb, As) potential harmful elements (PHE) were measured in three different environmental matrices (sediments, macroalgae, and fishes) from the Aeolian Archipelago and control areas both after one and ten months form a volcanic activity of particular relevance occurred at the end of October 2002. Results were analysed on a multivariate statistical basis with the aim to evaluate: I) general levels of pollution and increase of PHE due to the event; II) differences observed among tested matrices in the time of recovery after the occurrence of the critical event; III) the biological enrichment of PHE along the trophic web produced by the geological event. Results evidenced that volcanic emissions could represent a local source of particular relevance able to determine great enrichments of considered PHE in sediments and biological species. After ten months from the event, levels in sediments and macroalgae notably decreased, whereas fish species evidenced an increase, principally related to the greater dimensions of fishes caught during the second campaign. On the basis of the BEF, major enrichments were evidenced after one month whereas after ten months were recorded values reliable to an incomplete recovery. Concerning Cd, the BEF higher levels reported for the species S. cabrilla was probably related both to the diet and to the specific detoxification rates of this species.

The Aeolian Archipelago is a complex volcanic system constituted by seven islands and seamounts in the central Mediterranean (southern Tyrrhenian sea) and characterized by an active submarine hydrothermalism due to the presence of volcanoes, submarine canyons and hydrothermal sources. At the end of October 2002, three kilometers East from the island near the islet of Bottaro, a violent submarine gas eruption occurred. In the same period, after one month, a paroxysmal activity (a violent eruptive manifestation of the volcano) was observed in the Stromboli Island. This explosive event ejected incandescent scoria and booms fall out up to a distance of few kilometers from craters. Biodiversity associated with hydrothermal event was studied by integrating different methods. More in detail, fishing surveys and underwater visual census (UVC) by means of SCUBA divers were employed. Underwater visual census has underlined an immediate effect on the local habitat related to the noise, water heating, gas emission (CO2 and H2S), with braking away and dead of fish. The effects on biocenosis were observed for the next months on infralitoral and the associated community. The biocenosis ricolonization was observed the year after. Long term effects were related to the potential harmful trace elements (PHE), such as mercury (Hg), cadmium (Cd), lead (Pb), and arsenic (As). Rocks and sediments could release different trace elements, including PHE, when they are leached by hot fluids such as gas and hot waters which determine emissions at high temperature (around 30 and 130 °C). Sedentary benthonic fishes with longevity characteristics have been chosen in order to give a better description of the site investigated and the bioaccumulation phenomenon. Liver and muscle of the bluemouth rockfish Helicolenus dactylopterus dactylopterus (Delaroche, 1809) and the comber Serranus cabrilla (Linnaeus, 1758) were analyzed. Cd, and Pb determinations were performed by atomic absorption spectrometry with electrochemical atomization (GFAAS, Perkin-Elmer, mod. Analyst 700). Hg, and As were determined by atomic absorption via cold vapor generation (CV-AAS), according to the US-EPA 7473, and by atomic absorption after the hydride generation following the US-EPA 7011 method, respectively. A high trend of bioaccumulation was observed in selected species with the occurrence of higher levels after ten months from the event; observed higher levels in fisher were reliable to the growth rates as evidenced by the lower BEF observed after ten months; different species evidenced different bioaccumulation behavior, principally related to the trophic level and the diet of the species. Even though volcanic contribution seems to be of a little importance for most trace elements on a global scale, volcanic-derived emissions may become important in areas characterized by active volcanism which could represent local hot-spots of particular importance for the accumulation dynamics along the trophic web also representing a source of pollution for the whole marine ecosystem.

Since the exhalative crisis of 2002 cruises were carried out to investigate morphology, magnetic and gravity fields, fluid escape, plume anomalies, biological and microbiological activity, benthic fluxes, early diagenesis, mineralogy and geochemistry of water and sediments of the hydrothermal system of Panarea. The volcanic complex was mapped by multibeam, including backscatter analysis, and magnetometric surveys were done to detect low magnetization in areas with hydrothermal activity, i.e., vents, sulphide deposits, chimney fields. CTD by ship and on ROV detected acidic plumes at bottom (minimum pH value 6.5) and mid depths. An Automatic Benthic Chamber was deployed on a terrace (40m) and in depressions with gascharged and hydrothermally altered sediments (80m). At the 40m site, strong releases of Dissolved Inorganic Carbon (DIC) and Fe, Mn, Zn (75.7, 2.0, 2.9, 3.4 mmol m-2 day-1) were found. Average decrease of pH in the chamber was ~4 units day-1 with a H+ benthic flux of 0.32 mmol m-2 day-1). DIC values of seawater had average 2.3, increasing to 3.1 on degassing vents, while 7.5 mmol was measured on top of a bubbling core. ROV dives explored and sampled several sites; active chimneys (black, red crusts and yellowishorange precipitates at top) were recovered on the SE flanks of Basiluzzo; pH value of 5 was measured aboard on sediments. XRD and XRF data on the external crust showed Fe-Mn oxyhydroxides, including goethite and opal, with Co, Ce, Sr, Zn and Cu enrichments, whereas the inner part are depleted of Fe, Mn and other metals, mostly under detection limits. SEM imagery shows porous filamentous minerals, that are probably bacterial in origin. Dives to SW discovered fields of partially or totally relict chimneys at the same depth (~200m). Chimneys are present on the edges of slope failures and settled on areas of relative lower positive magnetic anomaly, indicating possible shallow depth level of hydrothermal alteration. Reddish crusts and sediments, and acid, gas boiling water (pH 5.5) were cored at 90 m depth upslope of the 'active' chimneys; upslope from the 'relict' chimney's fields, oxized-normal sediments were found. Biological investigations on the sediments revealed a community strongly dominated by the amphipod Ampelisca ledoyeri (43.8 % of the total abundance), probably dwelling in the tubepatches. Rare species were detected on the chimney's samples. The phylogenetic diversity of microbial communities in the precipitates collected on chimneys and on Bottaro vent was analyzed by bacterial and archaeal 16S rDNA clone libraries, showing a dominance of sulfur-oxidazing epsilon and gamma proteobacteria. Very interesting groups of archaea were revealed including methanotrophic Thermoplasmatales and members of SM1 candidate division. Overall prokaryotic diversity was found similar to that of deep sea hydrothermal vents and other sulfidic habitats. White microbial mats were found in an area S of Panarea, on a NS oriented fracture.

One rare post-larval stage and three adult specimens of Facciolella oxyrhyncha (Nettastomatidae) were found stranded on the shore of the Sicilian coast of the Strait of Messina, from 2006 to 2010. Morphometric and meristic data as well as some biological information were provided.