Sicilian Coast Research Articles

Finding of a rare Squatina squatina (Linnaeus, 1758) (Chondrichthyes: Squatinidae) along the Tyrrhenian coast of the Strait of Messina and its maintenance in an aquarium

The finding of a rare specimen ofSquatina squatinaoff the Sicilian coast of the Strait of Messina (Central Mediterranean Sea) and its maintenance in an aquarium is reported. The morphometric and meristic characters are presented. The record is proposed as a useful tool for raising attention to the state of this delicate species.

Integration of historical, archaeoseismic and paleoseismological data for the reconstruction of the early seismic history in Messina Strait (south Italy): the 1st and 4th centuries AD earthquakes

<p>Historical accounts, archaeoseismic and paleoseismological evidence allowed us to reappraise two earthquakes affecting northeastern Sicily and southern Calabria in the 1st (probably between 14 and 37) and 4th (likely between 361 and 363) centuries AD, to obtain a better reconstruction of their effects and to reconsider their sources.The 1st century event damaged the area from Oppido (Calabria) to Tindari (Sicily), roughly that of the February 6, 1783 Calabria earthquake. The similitude of these earthquakes is further stressed by the fact that they generated tsunamis, as recorded by historical data and by the tsunami deposits found at Capo Peloro, the oldest dated 0-125 AD, the youngest linked to the 1783 event. These earthquakes could be related to the same Calabria seismic source: the Scilla fault. Northeastern Sicily and southern Calabria were also damaged by one or more earthquakes in the 4th century AD and several towns were rebuilt/restored at that time. The hit area roughly coincides with that of the Messina 1908 earthquake suggesting similar seismic sources for the events. However, because close in time, historical descriptions of the 4th century Sicilian earthquake were mixed with those of the 365 Crete earthquake that generated a basin-wide tsunami most likely reaching also the Sicilian coasts. Reevaluating location, size, damage area and tsunamigenic potential of these two earthquakes of the 1st and 4th centuries AD is relevant for reassessing the seismogenic and tsunamigenic potential of the faults around the Messina Strait and the seismic hazard of the affected areas.</p>

Detection of viral encephalopathy and retinopathy virus (VERV) in wild marine fish species of the South Tyrrhenian Sea (Central Mediterranean)

Keywords: carrier, demersal fish, piscine nodavirus,RT-PCR, Tyrrhenian Sea.Betanodavirus infection has been reported to causediseases in a wide variety of marine fish species inaquaculture worldwide, and it is responsible ofsevere economic losses (Gagne et al. 2004; Walker& Winton 2010). Fish nodaviruses more com-monly cause disease and mortality of up to 100%in larval and juvenile stages, although adults canalso be affected (Munday & Nakai 1997; Gagneet al. 2004). Fish surviving infection can becomeasymptomatic carriers. Disease is characterized byabnormal swimming behaviours associated withvacuolar lesions in the nervous tissues containingviral particles. Clinical signs should be ascribed toone single disease, officially identified as viralencephalopathy and retinopathy (VER) also knownas viral nervous necrosis (VNN).The disease, present in the Mediterranean basin,affects farmed species such as European seabass,Dicentrarchus labrax L., and shi drum, Umbrinacirrosa L., but also wild species such as duskygrouper, Epinephelus marginatus (Lowe), and whitegrouper, Epinephelus aeneus (Geoffroy Saint-Hilaire) (Maltese & Bovo 2007). Nodavirus hasbeen identified in some wild apparently healthy fishbelonging to the following species: garfish, Belonebelone (L.), bogue, Boops boops (L.), thinlip greymullet, Liza ramada (Risso), whiting, Merlangiusmerlangus (L.), European hake, Merluccius merluc-cius (L.), flathead grey mullet, Mugil cephalus L.,red mullet, Mullus barbatus barbatus (L.), commonpandora, Pagellus erythrinus (L.), axillary seabream,Pagellus acarne (Risso), black goby, Gobius niger L.,European pilchard, Sardina pilchardus (Walbaum),gilthead seabream, Sparus aurata L., tub gurnard,Chelidonichthys lucerna (L.), and poor cod, Trisopte-rus minutus (L.), (Castric et al. 2001; Maltese et al.2005; Ciulli et al. 2006; Grodzki, Galletti & Ciulli2006).This study was aimed at determining the occur-rence of viral encephalopathy and retinopathy virus(VERV) in selected stocks of demersal fish species.Sampling: The study area is situated betweenCapo Suvero (the Calabrian coast) and Capo SanVito (the North-Western Sicilian coast) in theSouthernmost part of the Tyrrhenian Sea. Sam-plings were carried out during a summer trawl sur-vey and were performed with a commercial vesselequipped with an ad hoc designed net, with20 mm of stretched mesh size (Fiorentini et al.1999). A stratified random sampling method wasadopted (Relini 1998; Bertrand et al. 2002). Atotal of 23 hauls were carried out randomly allo-cated into five depth strata: A: 10–50 m(622 km

Ligia italica (Isopoda, Oniscidea) as bioindicator of mercury pollution of marine rocky coasts.

In this study, we evaluated the possible role of Ligia italica as a bioindicator for the monitoring of heavy metals pollution in the suppralittoral zone of marine rocky coasts. Between 2004 and 2011 specimens of L. italica were collected along the Eastern Sicilian coasts from sites known for their high pollution levels as they are near to an area where in September 2001 a refinery plant discharged into the sea some waste containing Hg. Other specimens were collected from the Vendicari Natural Reserve located about 30 miles from the polluted sites and used as control area. On a consistent number of animals, the concentration in toto of As, Cd, Cr, Hg, Ni, Pb, V, was determined by Atomic Absorption Spectrometry. On other animals, investigations were carried out in order to check for ultrastructural alterations of the hepatopancreas, that is the main metals storage organ in isopods. Results revealed the presence, in the animals collected in 2004 from the polluted sites, of considerable concentrations of Hg and of lower concentrations of other metals such as As, Pb and V. The Hg bioaccumulation resulted in remarkable ultrastructural alterations of the two cellular types (B and S cells) in the epithelium of the hepatopancreas. Surprisingly, a moderate amount of Hg was also found in specimens collected in 2004 from the Vendicari Natural Reserve, proving that the Hg pollution can also spread many miles away. Animals collected from the polluted sites in the following years showed a progressively decreasing Hg content, reaching very low levels in those from the last sampling. Also, the ultrastructural alterations found in the hepatopancreas of the animals from the last sample were quite irrelevant. In conclusion, Ligia italica can represent a good bioindicator and the ultrastructure of the hepatopancreas could be used as ultrastructural biomarker of heavy metals pollution in the supralittoral zones.

Finding of Eretmophorus kleinenbergi (Moridae) in the central Mediterranean Sea 93 years after its previous record, with a first description of sagittae and fresh coloration

The finding of a specimen of Eretmophorus kleinenbergi (Moridae) stranded on the shore on the Sicilian coast of the Strait of Messina (central Mediterranean Sea) is reported. Morphometric and meristic characters are given, and the description of sagittal otoliths and a colour photograph of a fresh specimen are provided.

Status and perspectives of the INFN Laboratori Nazionali del Sud

The nuclear research carried out at the Laboratori Nazionali del Sud is mainly based on two ion accelerators, a 15 MV Tandem and a K800 superconductive cyclotron. The large variety of stable and radioactive beams produced and their wide energy range, together with the availability of high performance detection systems, allow for experimental research in the fields of the nuclear structure, reaction mechanisms and nuclear astrophysics. A continuous upgrading of the beam production and detection facilities is performed to mantain the role of the LNS in the panorama of the European nuclear laboratories. In addition the research activity in astroparticle physics led to the construction of two underwater laboratories in front of the Sicilian coast. They allow to check and validate submarine technologies in view of the realization of the European project KM3NeT, consisting in the installation of an observatory for high energy cosmic neutrinos in deep sea. All these experimental resources also represent formidable tools for applied researches that cover multidisciplinary fields concerning proton therapy, cultural heritage, seismology, environmental sciences and many others.

Genetic considerations on the introduction of farmed fish in marine protected areas: The case of study of white seabream restocking in the Gulf of Castellammare (Southern Tyrrhenian Sea)

Human exploitation has drastically reduced the abundance and distribution of several marine fish and invertebrate populations through overfishing and habitat destruction. Restocking can potentially mitigate these impacts and help to reconstitute depleted stocks but genetic repercussions must be considered. In the present study, the degree of genetic similarity between white seabream (Diplodus sargus Linnaeus 1758) individuals reared for restocking purposes and the receiving population in the Gulf of Castellammare fishery reserve (Sicily, Italy) was assessed using microsatellites. We also inferred the spatial pattern of the genetic structure of D. sargus and connectivity along Sicilian coasts. The farmed population showed significant heterozygosity deficiency in 6 loci and an important reduction in the number of alleles, which could indicate an incipient inbreeding. Both the farmed population and the target one for restocking (Castellammare fishery reserve), showed high and significant values of genetic differentiation due to different allele frequencies, number of privative alleles and total number of alleles. These findings indicate a low degree of genetic similarity between both populations, therefore this restocking initiative is not advisable. The genetic connectivity pattern, highly consistent with oceanographic currents, identified two distinct metapopulations of white seabream around Sicily. Thus it is recommended to utilize broods from the same metapopulation for restocking purposes to provide a better genetic match to the wild populations.

Colonization of the Aeolian Islands byPimelia rugulosa rugulosaGermar, 1824 (Coleoptera: Tenebrionidae) inferred from the genetic structure of populations: geological and environmental relations

The darkling beetle Pimelia rugulosa rugulosa Germar, 1824 was selected to investigate the process of colonization in a volcanic archipelago and the role of volcanism in determining spatial patterns of genetic variability. Analyses were conducted in the Aeolian Islands, located in the central Mediterranean directly off the Sicilian coast. Genetic variability and geographic structure were studied in individuals from each island of the archipelago based on sequences of the cytochrome c oxidase subunit 2 mitochondrial gene; a network approach was employed to identify haplotype lineages. A strong genetic structure, with no haplotype sharing among islands, was observed. Six separate lineages were identified that independently colonized different islands of the archipelago from the mainland and differentiated locally to form small haplogroups. Variability of observed haplogroups is correlated with island age and a positive correlation between tenebrionid diversity and mitotype diversity is reported. Some, yet undescribed, catastrophic event is hypothesized to explain the depletion of a substantial part of the genetic, as well as biological diversity in the island of Filicudi. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104, 29–37.

Daytime pelagic schooling behaviour and relationships with plankton patch distribution in the Sicily Strait (Mediterranean Sea)

In this study, hydroacoustic data collected with a scientific echosounder working at two frequencies (38 and 120 kHz) over the continental shelf off the southern Sicilian coast were used in order to investigate the relationship between fish schools and plankton patches. Specifically, image analysis algorithms were applied to raw echograms in order to detect and characterise pelagic fish schools and plankton aggregations, considered as a proxy of food availability. The relationship was first investigated using estimated total plankton biomass over the whole water column and, second, by dividing the study area into three sub-regions and further distinguishing plankton patches between the surface and the bottom. In the relatively lower plankton abundance areas of Zone 1 (northern sector of the study area), results showed an inverse relationship between the biomass (and density) of fish schools and the biomass of co-occurring plankton patches located close to the bottom. Instead, over the Sicilian-Maltese shelf (Zone 3), characterised by higher plankton abundances, a direct relationship was found when using plankton data from the whole water column. The observed difference between Zones 1 and 3 is probably due to diverse dominant fish species in the two sub-regions.

Daytime pelagic schooling behaviour and relationships with plankton patch distribution in the Sicily Strait (Mediterranean Sea)

In this study, hydroacoustic data collected with a scientific echosounder working at two frequencies (38 and 120 kHz) over the continental shelf off the southern Sicilian coast were used in order to investigate the relationship between fish schools and plankton patches. Specifically, image analysis algorithms were applied to raw echograms in order to detect and characterise pelagic fish schools and plankton aggregations, considered as a proxy of food availability. The relationship was first investigated using estimated total plankton biomass over the whole water column and, second, by dividing the study area into three sub-regions and further distinguishing plankton patches between the surface and the bottom. In the relatively lower plankton abundance areas of Zone 1 (northern sector of the study area), results showed an inverse relationship between the biomass (and density) of fish schools and the biomass of co-occurring plankton patches located close to the bottom. Instead, over the Sicilian-Maltese shelf (Zone 3), characterised by higher plankton abundances, a direct relationship was found when using plankton data from the whole water column. The observed difference between Zones 1 and 3 is probably due to diverse dominant fish species in the two sub-regions.

Composition and geochemistry of clay sediments offshore the northeastern Sicilian coast (Southeastern Tyrrhenian Sea, Italy)

Grain-size, mineralogical and chemical analyses were carried out on fine fraction of sediments collected in the Gulfs of Patti and Milazzo, two borderland basins in the Southern Tyrrhenian extending offshore the northeastern Sicilian coast. Results of granulometric analyses on size fractions smaller than 63 μm showed that the investigated samples can be classified mainly as clayey silts. The coarse fractions (>63 μm), examined by optical microscopy, consist of a terrigenous component, representing in some samples about 98–99% of the total sediment, and by a biogenic component. This latter is mainly made up of benthic Foraminifera. The mineralogical composition of the fine fraction, determined by X-Ray diffractometry, is represented by muscovite, quartz, clay minerals, carbonates (calcite) and, in some samples, by calcium and sodium-rich plagioclases. The method of saturation with K and Mg, followed by ethylene glycol solvation and heating, are used for a qualitative determination of the clay minerals. Clay mineralogical composition is characterized by the dominance of clinochlore and illite, with minor amounts of smectite (especially montmorillonite) and vermiculite. The chemical data reflect the main mineralogical composition showing a uniform quantitative composition, with high Al 2O 3 and SiO 2 values and very few variations in the relative abundance of the other components. The Cr/Th, Th/Sc, Th/Co and La/Sc ratios suggest a felsic nature of the source rocks. Finally the geochemical parameters such as V/Cr, U/Th, Ni/Co and Cu/Zn ratios indicate that examined sediments were deposited under oxic environments.

Flash-flood hyperpycnal flows generating shallow-water landslides at Fiumara mouths in Western Messina Strait (Italy)

On October 1, 2009, a small area along the Sicilian coast between the villages of Scaletta Zanclea and Giampilieri was struck by intense and concentrated rainfall causing countless small landslides widespread over the catchment area of steep subaerial creeks, locally known as Fiumara. Dense and quick debris flows were channelized within the Fiumara and destructively hit the villages and entered the sea, where they likely transformed into hyperpycnal flows. The availability of pre- and post-flood high-resolution bathymetry allows us to recognize the main features and the most significant morphological variations related to the impact of the flows on the seafloor. The passage of hyperpycnal flows on the seafloor possibly produced a suite of mass-wasting events, encompassing sheet landslides (i.e. erosive scours), retrogressive slope failure on loose sediment at the canyon headwall and rock-falls on the conglomeratic bedrock along canyon sidewall. The possible causes of these events are discussed on the basis of available morphological evidence and geotechnical considerations. Finally, the widespread occurrence of mass-wasting features (i.e. submarine landslide scars) morphologically similar to those generated by the 2009 flash flood allows us to hypothesize, from one side, a strong correlation between this catastrophic event and the evolution of submarine canyons, and from the other side, the possible use of these features for the assessment of flash-flood occurrence.

Response of benthic foraminifera to heavy metal contamination in marine sediments (Sicilian coasts, Mediterranean Sea)

To examine the suitability of benthic foraminifera and their test deformations as bioindicators of pollution in coastal marine environments, we studied foraminifera and metal concentrations in 72 marine sediment samples, collected from the inner shelf along the Sicilian coast (Gulfs of Palermo and Termini) and on the south-eastern coast of Lampedusa Island. These areas are characterised by different environmental conditions. On the basis of pollution sources and foraminiferal assemblages, we recognised different zones in the Gulf of Palermo. The most polluted zones showed high metal concentrations, and low diversity of benthic foraminifera with species typical of stressed environments. By contrast, the lowest polluted zones showed a high population density and the highest percentages of epiphytes. Epiphytes were abundant where a Posidonia oceanica meadow was present and decreased in the most polluted zones. Sediments of the Gulf of Termini and Lampedusa exhibited high percentages of benthic foraminifera typical of well-oxygenated waters and low concentrations of metals, with the exception of sites located near sewage outfalls and harbour areas. Furthermore, even though deformed tests are commonly known in natural stressed environmental conditions, this study shows that in the most polluted zones, benthic foraminifera were characterised by the highest percentages of deformed individuals.

FUZZY IMPACT ASSESSMENT ON THE LANDSCAPE: THE KOBOLD PLATFORM IN THE STRAIT OF MESSINA CASE STUDY

This paper introduces a new semi-quantitative method to model a landscape assessment, by using a fuzzy analysis approach. The main aim of this research is to evaluate the landscape impact of the Kobold prototype in the Straits of Messina. The Kobold turbine, patented in 1998, is a prototype used to extract energy from the marine currents utilizing a vertical axis turbine. The site where the plant is positioned is very close to Ganzirri (Italy), on the Straits of Messina, near the Sicilian coast, at a distance of about 150 – 200 m from the shore. The results allow us to state that the measure of the impact landscape has been a huge success. In fact, the fuzzy variable representing the impact is 98% below the tolerance threshold.

Distribution of rare earth elements in marine sediments from the Strait of Sicily (western Mediterranean Sea): Evidence of phosphogypsum waste contamination

Concentrations of rare earth elements (REE), Y, Th and Sc were recently determined in marine sediments collected using a box corer along two onshore–offshore transects located in the Strait of Sicily (Mediterranean Sea). The REE+Y were enriched in offshore fine-grained sediments where clay minerals are abundant, whereas the REE+Y contents were lower in onshore coarse-grained sediments with high carbonate fractions. Considering this distribution trend, the onshore sediments in front of the southwestern Sicilian coast represent an anomaly with high REE+Y concentrations (mean value 163.4μgg−1) associated to high Th concentrations (mean value 7.9μgg−1). Plot of shale-normalized REE+Y data of these coastal sediments showed Middle REE enrichments relative to Light REE and Heavy REE, manifested by a convexity around Sm–Gd–Eu elements. These anomalies in the fractionation patterns of the coastal sediments were attributed to phosphogypsum-contaminated effluents from an industrial plant, located in the southern Sicilian coast.

The NEMO project: A status report

The latest results and the activities towards the construction of a km 3 Cherenkov neutrino detector carried out by the NEMO Collaboration are described. Long-term exploration of a 3500 m deep-sea site close to the Sicilian coast has shown that it is optimal for the installation of the detector. The NEMO Phase-1 project has validated several technologies proposed for the construction of the km 3 detector on a test site at 2000 m depth. The new infrastructure on the candidate Capo Passero site set up as part of the Phase-2 project will provide the possibility to test detector components at 3500 m depth.

How building an underwater pipeline connecting Libya to Sicilian coast is affecting environment: polycyclic aromatic hydrocarbons (PAHs) in sediments; monitoring the evolution of the shore approach area of the Gulf of Gela (Italy)

The purpose of this study was to determine the variation of concentrations and distribution of PAHs in the sediments of the Gela coastal area (Italy) caused by the construction of an underwater pipeline connecting Libya to Sicilian coast. The receiving terminal of offshore pipeline, crossing the Mediterranean Sea, 516 Km long, up to 1127 meters deep, is located in Gela (Sicily, Italy). No bibliographic data regarding hydrocarbons are available for this area. In this paper we report the results of analysis on the water and organic along PAHs.The total concentrations of 16 PAHs in the sediments, analyzed during five surveys, ranged from 2.4 to 434 μg/kg of dry weight. The highest concentrations of total PAHs were found in sediments during the monitoring campaign immediately following the laying of the pipeline. A progressive decrease during the subsequent surveys was observed: The found concentrations was in the direction of restoring the initial situation. Highest levels of PAHs concentration have been often observed in sample stations endowed with highest organic matter content.

Role of physical forcings and nutrient availability on the control of satellite-based chlorophyll a concentration in the coastal upwelling area of the Sicilian Channel

The northern sector of the Sicilian Channel is an area of favourable upwelling winds, which ought to support primary production. However, the values for primary production are low when compared with other Mediterranean areas and very low compared with the most biologically productive regions of the world’s oceans: California, the Canary Islands, Humboldt and Benguela. The aim of this study was to identify the main factors that limit phytoplankton biomass in the Sicilian Channel and modulate its monthly changes. We compared satellite-based estimates of chlorophyll a concentration in the Strait of Sicily with those observed in the four Eastern Boundary Upwelling Systems mentioned above and in other Mediterranean wind-induced coastal upwelling systems (the Alboran Sea, the Gulf of Lions and the Aegean Sea). Our results show that this low level of chlorophyll is mainly due to the low nutrient level in surface and sub-surface waters, independently of wind-induced upwelling intensity. Further, monthly changes in chlorophyll are mainly driven by the mixing of water column and wind-induced and/or circulation-related upwelling processes. Finally, primary production limitation due to the enhanced stratification processes resulting from the general warming trend of Mediterranean waters is not active over most of the coastal upwelling area off the southern Sicilian coast.

Seagrasses along the Sicilian coasts

All seagrass species known from the Mediterranean basin have been recorded along the Sicilian coast, where studies have been carried out at a very local scale and information is fragmented or confined to the grey literature. The objective of this article is to summarise and evaluate current knowledge on seagrass species on the Sicilian coasts, providing an overview of species distribution, genetic diversity, biology and ecology, based on the literature and unpublished data. Most literature studies have been carried out on Posidonia oceanica meadows because of their wide distribution, complexity and ecological importance. In this study, the analyses carried out on P. oceanica structural and functional features show that the Sicilian meadows are in good condition with respect to the Mediterranean average, probably because of relatively low anthropogenic pressure and favourable ecological conditions. The available data on this species summarised in this article represent an important starting point from which to build effective plans for understanding levels of environmental threats and for supporting conservation strategies for these important ecosystems. Conversely, the limited information available on other seagrasses only allows the description of some structural and functional features, and does not permit to drive overall conclusions on their general health status.

Macrophytobenthos and the ecological status of coastal waters around Sicily

This article gives a picture of recent studies on the phytobenthos of Sicily, paying particular attention to research carried out in the last 10–15 years. Twenty new taxa have been described from Sicily, and floristic studies have recorded 823 taxa at the specific and infraspecific levels. Vegetational studies have been used to verify changes that have possibly occurred in Sicilian areas over the last 30 years. Particular attention was also paid to 22 taxa considered to have been introduced into the Mediterranean Sea and which are found along the Sicilian coast. Applied research dealt mainly with management of the territory, promotion of a sustainable development model for the coastal zone, and using macroalgal communities to assess the quality of Sicilian waters. Finally, some suggestions for studies that should be carried out to increase phytobenthic knowledge of Sicilian coastal waters are made.