Search

Anthropogenic microparticles (AMs) were found for the first time in specimens of Trematomus bernacchii collected in 1998 in the Ross Sea (Antarctica) and stored in the Antarctic Environmental Specimen Bank. Most of the identified AMs were fibers of natural and synthetic origin. The natural AMs were cellulosic, the synthetic ones were polyester, polypropylene, polypropylene/polyester, and cellulose acetate. The presence of dyes in the natural AMs indicates their anthropogenic origin. Five industrial dyes were identified by Raman spectroscopy with Indigo occurring in most of them (55%). Our research not only adds further data to the ongoing knowledge of pollution levels in the Antarctica ecosystem, it provides an interesting snapshot of the past, highlighting that microplastics and anthropogenic fiber pollution had already entered the Antarctic marine food web at the end of the ‘90s. These findings therefore establish the foundations for understand the changes in marine litter pollution over time.

Pollution deriving from textile wastes, including industrial and household waste, is recently of great interest due to their environmental impacts. Anthropogenic and synthetic fibers are responsible for negative effects on the quality of water and soil, and, also, their presence damages plant and animal health. In this work, the authors revealed the occurrence of man-made cellulose fibers in specimens of Boops boops from the Northern Sicilian coasts. Bogue was chosen as target species as it has been used as an indicator within the European Marine Strategy Framework Directive (MSFD 2008/56/EC) in order to value the “microplastics status” in the stomach contents. Of the 30 specimens examined, 63.3% of these had ingested fibers items. The number of fibers ranged from 1 to 10 per specimens with an average of 2.7 items/specimen. Fibers length ranged from 0.5 to 30 mm, most of them were black (95%), and a small percentage was red (5%). The ingestion of man-made cellulose fibers, observed for the first time, in Boops boops in the Mediterranean Sea wake-up call and it should attract the attention of the EU for new guidelines where this new type of contaminant is classified harmful as well as plastics.

Environmental pollution by plastic particles is of major global concern, as a potential threat to aquatic organisms and ecosystems. The accumulation of microplastics in freshwater and marine environments has strong ecological implications due to their long persistence, potential toxicity, and ability to adsorb other pollutants, acting as vectors of pathogens. Nevertheless, while the number of studies on the presence of microplastics in the wild fish increased, less attention has been paid to the farmed fish species. Here, we investigated the occurrence of microparticles in the digestive tracts of Sparus aurata and Cyprinus carpio at different life stages and reared by an intensive and semi-intensive production system, respectively. Our results showed the presence of natural microfibers and microplastics, with microfibers (~ 90%) being the dominant type. In both fish species, the presence of microparticles was not revealed at larval stage. Fry and adult S. aurata specimens showed microfiber abundances of 0.21 and 1.3 items/individual, respectively. A lower load of microparticles (p < 0.05) occurred in fry (0.06 items/individual) and adult C. carpio specimens (0.25 items/individual). As to the chemical composition of the micro-items, natural (20%), semi-synthetic (28%), and single or blended synthetic fibers (52%) were identified in S. aurata. Linen, rayon, lyocell, cotton: polyester and polyester (12.5% concentration for each polymer) fibers were identified in C. carpio, while PTFE (37.5%) was present as fragments. Rayon was the most frequent chemical type (21.2%). The polymer composition of the extracted microparticles showed significant differences between the fish species analysed (p < 0.05). Notably, a considerably lower contamination level of synthetic polymers (average 0.11 items/individual) was detected in the farmed fishes compared with the data obtained in other studies on feral ones. To the best of our knowledge, this is the first study reporting the plastic and the non-plastic microfiber contamination in the farmed S. aurata and C. carpio at different life stages.

The present investigation focuses on Boops boops specimens gathered in the Gulf of Patti in 2010. Providing a snapshot from the past, this paper represents, chronologically, the first record of microplastic ingestion in the Mediterranean bogue. The plastic abundance and composition in gastrointestinal tracts of the bogue was assess, in order to improve the knowledge on spatial-temporal variability of microplastics pollution in the Mediterranean basin and in particular, in the southern Tyrrhenian Sea. In a total of 65 specimens, 180 particles of plastic (2.8 items/specimens), mainly belonging to microplastics class, were found. Fragments (63%) and fibres (30%) were the predominant shape categories. Eleven polymers were identified: polypropylene and polyethylene were the most abundant. Several synthetic polymers belonging to the class of elastomers were also observed. The study area is strongly influenced by the absence of trawl fishing activities and a low mixing level of the seabed that, together with the confluence of different watercourses and the presence of different kind of anthropic impact, including motorway, could make it a 'waste disposal site'. Finally, our results suggest the usefulness to retrieve older samples to better understand spatial-temporal changes in marine litter pollution over time.

Aim: Previous analyses of marine fish species richness based on presence-absence data have shown changes with latitude and average species size, but little is known about the underlying processes. To elucidate these processes we use metabolic, neutral and descriptive statistical models to analyse how richness responds to maximum species length, fish abundance, temperature, primary production, depth, latitude and longitude, while accounting for differences in species catchability, sampling effort and mesh size. Data: Results from 53,382 bottom trawl hauls representing 50 fish assemblages. Location: The northern Atlantic from Nova Scotia to Guinea. Time period: 1977–2013. Methods: A descriptive generalized additive model was used to identify functional relationships between species richness and potential drivers, after which nonlinear estimation techniques were used to parameterize: (a) a ‘best’ fitting model of species richness built on the functional relationships, (b) an environmental model based on latitude, longitude and depth, and mechanistic models based on (c) metabolic and (d) neutral theory. Results: In the ‘best’ model the number of species observed is a lognormal function of maximum species length. It increases significantly with temperature, primary production, sampling effort, and abundance, and declines with depth and, for small species, with the mesh size in the trawl. The ‘best’ model explains close to 90% of the deviance and the neutral, metabolic and environmental models 89%. In all four models, maximum species length and either temperature or latitude account for more than half of the deviance explained. Main conclusions: The two mechanistic models explain the patterns in demersal fish species richness in the northern Atlantic almost equally well. A better understanding of the underlying drivers is likely to require development of dynamic mechanistic models of richness and size evolution, fit not only to extant distributions, but also to historical environmental conditions and to past speciation and extinction rates, Sí

Knowledge on fish stock units and their boundaries is still poor in the Mediterranean despite the relevance of this information for developing accurate stock assessment and effectively managing fisheries. The aim of this work is to identify parasite species that might serve as biological tags for discrimination of red mullet stocks Mullus barbatus and M. surmuletus, off the northern and southern coasts of Sicily (central Mediterranean). Stephanostomum sp. metacercariae were selected as good biological tags for M. barbatus and M. surmuletus. Specimens caught in the Strait of Sicily showed a high level of metacercariae infections while no infected fish was found in the Southern Tyrrhenian Sea. Furthermore, cestode larvae (order Trypanorhyncha), and adult and larval digeneans were considered suitable as biological tags for stock discrimination in M. surmuletus, presenting statistically different epidemiological levels between the two areas. Results suggest a likely occurrence of distinct populations of red mullets in two areas of the central Mediterranean on the basis of parasite infestations.

A sample of 67 European hake Merluccius merluccius were examined to highlight the ingestion of microplastics in the Tyrrhenian Sea. In all samples, 31 black fibres were found in the stomach contents corresponding to 46.3% of the specimens. The data presented here could be important for the implementation of the EU Marine Strategy Framework Directive in Mediterranean waters.

Subtidal shell deposits of the edible bivalve Arca noae in the Strait of Messina (Central Mediterranean) were investigated and compared with an adjacent live population, testifying that dead and live populations were similar but distinct. The age–class structure of the two compared populations, whose lifespans ranged from 5 to 7 y, indicated that in this area unexploited Noah's ark stocks have generally low survival and recruitment. Shell morphometrics and size distributions suggested that the shell deposits were descriptive of the premortality population structure, as expected in a mass mortality episode.

The fan mussel Pinna nobilis is threatened by several anthropogenic disturbances that are only partially mitigated by current conservation measures. In the Faro Lake Natural Reserve, the fan mussel population suffers from insufficient recruitment while, due to periodic dredging, a high larval supply within the canals does not support a stable population. In the present study, a robust number of fan mussel specimens were transplanted from a high-impact site to a guarded area to test the effects of transplantation on future conservation efforts. Over a 12-mo period, high survival and elevated growth were observed in the test population in comparison with the local population, demonstrating transplantation as a feasible and efficient method to prevent P. nobilis population decline. Such small-scale experiments provide useful indications for better management approaches for both of the threatened species and the natural hosting environment.

Mediterranean young-fish oriented experimental bottom trawl surveys represent a precious source of information on both past and current standing stocks and their life history traits and exploitation state. In the present note, taking the occasion of the same vessel employed in the South of Sicily (Central Mediterranean), an indirect approach has been implemented to compare MEDITS (Mediterranean International Bottom Trawl Survey) and GRUND (Gruppo Nazionale Demersali) abundance and biological features of the blackmouth catshark Galeus melastomus Rafinesque, 1810 to highlight gear and season effects if any. Data were gathered between 1994 and 2006, in spring-summer (MEDITS) and autumn (GRUND). The density and biomass indexes and occurrences were substantially lower in spring than in autumn. On the contrary, the biological traits were more similar, although significant differences were detected in the length frequency distribution. The homogeneity of life traits between seasons and the critical features showed in this study demonstrate that an annual experimental trawl survey can be enough to monitor G. melastomus. Similar analysis could be useful to highlight seasonal and gear effects on the other demersal stocks to better figure out limits and possibility of Mediterranean young-fish oriented experimental bottom trawl surveys data.

This study highlights plastics occurrence in five demersal fish species from the Southern Tyrrhenian Sea: the Red mullet Mullus barbatus barbatus, the Piper gurnard Trigla lyra, the Blackmouth catshark Galeus melastomus, the Lesser spotted dogfish Scyliorhinus canicula and the Brown ray Raja miraletus. Overall, 125 fish were examined: 21 Red mullets, 16 Piper gurnards, 75 Blackmouth catsharks, 72 Dogfish and 1 Brown ray. The percentage of fish with ingested plastics was 14.4% with 0.24 items per specimen. The majority of the debris were fibers and the application of infrared and Raman spectroscopy allowed the identification and discrimination of plastic and non-plastic fibers. The plastic debris isolated were mainly microplastics (94.1%), while macroplastics occurrence was very low (5.9%). The plastics were identified as polypropylene, Teflon, nylon, kraton G (triblock copolymer) and polyethylene. Also cellulose was detected. S. canicula was the species with the highest number of plastic pollutants.

The present study investigates the occurrence of plastic pollution in two commercially important marine teleosts ( Zeus faber and Lepidopus caudatus ) from the northern coasts of Sicily (Tyrrhenian Sea). Plastics occurrence in the gastrointestinal tract was higher in Lepidopus caudatus (78.1%) than Zeus faber (51.4%). Debris characterization, carried out by micro-Raman spectroscopy, allowed identified the main types of found polymers as: polypropylene (PP), polyamide (PA), nylon and, to a lesser extent, polyethylene (PE). Of the two fish species studied, the silver scabbardfish appeared to be the more vulnerable to plastic ingestion. Our study represents a starting point that may pave the way for future investigation of the fate, accumulation and transfer of plastic debris to upper trophic levels, to verify their potential toxicity and to better understand strategies to mitigate this phenomenon.

In this work it is reported for the first time the characterization of microplastics from sea water samples and in two congener species of seabreams: Pagellus erythrinus and P. bogaraveo, Mediterranean fish species of great commercial importance. An experimental survey was conducted on May-June 2017 in the southernmost part of the Tyrrhenian Sea. Microplastics found in the sea water and in the grastrointestinal tract of two teleosts were characterized by Raman and IR spectroscopies. Microplastics found in sea water samples appeared in the form of fragments made of plastics of low and high density (PVC and LPDE). All the microplastics found in fish belonged to Nylon 66, typical fibers used in industry and in fisheries. Our findings highlighted the importance of further studies along the food web chain for a better understanding of the diffusion and possible consequences of this terrible threat.

We report the presence of microplastics on the external surface and in the gastrointestinal tract of white late-larval and juvenile stages (fry) of clupeid fishes caught in the Southern Tyrrhenian Sea. The average highest number of plastics debris was recorded on Sardina pilchardus (0.53 items/specimen); a lower average number of items was observed for Engraulis encrasicolus (0.26 items/specimen). The plastics were characterized by fibers that differed in shape, colour and composition. Polyester, polypropylene, polyacrylonitrile, polyethylene, polyamide, nylon, rayon and polyurethane segments were detected by Raman and FTIR spectroscopies. Traces of organic components and dyes, compounds that are generally included in the polymer matrix to modify its base properties, were also identified on microplastics. Our results raise concerns for the potential transfer of synthetic materials through the marine food web and into humans, given the prominent role of S. pilchardus and E. encrasicolus within the food web as main food source for many marine species.

Hollowsnout grenadier (Coelorinchus caelorhincus) collected from several locations in the Strait of Sicily (southern Sicilian coasts) were examined for the presence of Lophoura edwardsi, a parasitic copepod. A total of 94 out of 924 C. caelorhincus were parasitized. Each parasite was attached with the cephalosome buried deep in the dorsal musculature of the host. The parasite caused skin ulceration and deep lesions resulting in granulomatous and inflammatory reactions extending deep into the musculature of the host. A longitudinal gradient (W-E) in parasite presence was detected with prevalence ranging from 0 to 34.6%. This study establishes the record for the shallowest finding of the genus Lophoura, just below 100 m. A negative correlation was found between prevalence vs depth and host length. No copepods were observed on C. caelorhincus longer than 70 mm (pre-anal length). Epidemiological data from experimental trawl surveys combined with GIS modelling of marine parasites might result in better management of marine resources. The wide spatial coverage, such as that investigated by MEDITS trawl surveys, may allow a distribution analysis of marine parasites that would prove to be extremely useful in identifying deep-sea fish stocks.

Fisheries products found in the landing places or markets usually represent a fraction of what has been originally taken out from the sea by fishermen. A more or less variable amount of the gross (or overall or initial) catch, in fact, is returned either dead or alive to the sea for multiple reasons. This phenomenon, generally known as 'the discard problem', has raised more and more global concern especially in the last decades since introducing more selectivity gears and acquiring more reliable catch data (also about the survival rate of the discarded specimens) are considered basic requirements in the current management plans for recovering and rebuilding fish stocks. To this concern, the current Common Fisheries Policy aims to reduce the discard rate in the European waters through the introduction of a landing obligation (better 'discard ban') according to which all the specimens of the 'target' stock caught must be landed. This chapter focuses on the characterization of the catch returned to the sea 'potential' available to be landed after the introduction of landing obligation, and the possible use as a potential food source in aquaculture (the direct use for human consumption is in fact prohibited).

Aquaculture currently accounts for approximately 50 % of fish consumed by humans. The future development of aquaculture will be greatly constrained by the increasing costs of fishmeal and fish oil. To remedy this situation, scientific research and feed manufacturers have made a significant progress by looking for alternative protein sources for use in fish diets in order to develop feeds that provide adequate nutrition for animals' growth, while reducing to minimum the use of traditional sources of protein. This chapter aims at critically reviewing recent studies, carried out worldwide, about the effects of the inclusion of new protein sources as insect, poultry by-products, meat and bone meals and other protein sources alternative to fish meal in aquafeeds. In particular, the impacts of these protein sources in terms of growth, nutrient digestibility, fillet quality traits and sensorial perception in the most important farmed marine and freshwater fish species are evaluated.

Fishmeal and fish oil have been for a long time the dominant raw materials for aquaculture feeds but these are limited and finite resources. Plant oils extracted from oilseeds are the main candidates as sustainable substitutes for fish oil in fish feeds and many studies have demonstrated the feasibility of their use. Plant oils are rich in linoleic and α-linolenic acids but lack in eicosapentaenoic and docosahexaenoic acids that belong to omega-3 long-chain polyunsaturated fatty acids and whose food consumption has been shown to have beneficial effects on human health. In the light of these considerations, it is clear that the most important problem of the replacement of dietary fish oil with plant oils is a reduction of the nutritional value of the flesh of farmed fish. This review attempts to provide an overview of the effects of the major plant lipid sources alternative to fish oil tested in studies carried out on farmed fish species.

The fast increase in marine aquaculture productions has generated some problems related to optimization of fish feed. Moreover, the search for alternative raw materials to supplement or replace fishmeal and fish oil has made the introduction of additives into the diet necessary. Diet additives have recently attracted attention and investments of the aquaculture industry and, consequently, researches aimed at evaluating the costs/benefits ratio and the effects on organisms and environments are increasing. In general, additives are nutritive or nonnutritive ingredients that are added to the diet alone or in combination with each other and that are present in small quantities. Their functions are different: preserve the physical and chemical features of the diet, enhance animal health and welfare, improve the quality of final product and maintain the quality of aquatic environment. This chapter provides an overview of the use of vitamins, minerals and antioxidants in fish feeds. In addition to these natural substances, also enzymes are proposed as new alternative aquafeed additives. The effects on fish growth, welfare, reproduction and health status of the above-reported additives are discussed.

The branchiuran parasite Argulus vittatus (Crustacea: Branchiura: Argulidae) was collected from the pectoral fin of the axillary bream Pagellus acarne, comber Serranus cabrilla, and greater amberjack Seriola dumerili from the northern coasts of Sicily (Mediterranean Sea), Italy. Pagellus acarne, Serranus cabrilla, and Seriola dumerili are new hosts for A. vittatus.

This paper provides the first report of the leech, Pontobdella muricata (Linnaeus, 1758), in the Tyrrhenian Sea. The leech was found on the brown ray, Raja miraletus (Linnaeus 1758), and on the spotted ray, Raja montagui (Fowler, 1910), caught by trawling during autumn 2014. Complete sequence of 18S rRNA gene, COI mitochondrial gene and partial sequences of the mitochondrial 12S rRNA gene corroborate the determination based on morphological characteristics., U radu se iznosi prvi nalaz pijavice, Pontobdella muricata (Linnaeus, 1758), u Tirenskom moru. Pijavica je pronađena na modropjegoj raži, Raja miraletus (Linnaeus 1758) i na crnopjegoj raži, Raja montagui (Fowler, 1910), iz koćarskih lovina tijekom jeseni 2014. godine. Kompletna sekvenca 18S rRNA gena, COI mitohondrijskog gena i djelomične sekvence mitohondrijskog 12S rRNA gena potvrđuju određivanje koje se zasniva na temelju morfoloških svojstava.

The ability to observe and predict trawling-induced patterns at spatial and temporal scales that are relevant to inform realistic management strategies is a challenge which scientists have consistently faced in recent decades. Here, we use fish feeding behaviour, a biological trait easily impaired by trawling disturbance, to depict alterations in fish condition (i.e. individual fitness) and feeding opportunities. The benthivorous fish Mullus barbatus barbatus was selected as a model species. The observed trends of responses to trawling in prey species confirmed the effectiveness of a non-trawled zone in sustaining higher levels of diet diversity (e.g. quantity and quality of ingested prey) and fish condition values (e.g. morphometric and physiological Condition Index). Changes observed in fish prey selection confirmed the role of trawling disturbance in modifying the local soft bottoms community, producing alterations of prey availability that trigger shifts in fish diet. Trawling-induced feeding patterns, mirrored through stomach contents, can positively or negatively affect fish condition, the main driver of population dynamics in maintaining carrying capacity levels. Due to the widespread socio-economic value of the red mullet fishery, and the current exploitation status, evidence gathered by the proposed bottom-up trait based approach might inform future trawling adaptation strategies, and tailor spatial conservation measures supporting an Ecosystem-Based Fisheries Management.

A synthetic analysis of the distribution, abundance and some biological traits of the common pandora (Pagellus erythrinus) was performed. Data were gathered in 15 experimental bottom trawl surveys carried out off the southern Tyrrhenian Sea from 1994 to 2008. A total of 2,166 P. erythrinus were found in the investigated area, with a preference for the upper continental shelf (10–100 m). The highest persistence was recorded in the trawl-banned areas. The sex ratio Sr = F/(F + M) ranged between 0.60 and 0.96 (overall 0.78). The size at which 50 % of the individuals were mature was 157 and 170 mm total length for females and males, respectively. The length–weight relationship for all individuals was described by the following parameters: a = 0.016 and b = 2.905. Growth was evaluated (sexes combined) by applying length-based methods; up to eight significant modal components were evidenced. The von Bertalanffy growth parameters for the whole population were estimated at L ∞ = 454 mm, K = 0.08 and t 0 = −2.57. The present results are in agreement with the information available for the other Mediterranean stocks suggesting common biological features.

Coelioscopy is a surgical technique in which small incisions are made into the coelomic cavity through which specific instrumentation is inserted to evaluate the internal structures within. For this reason, coelioscopy must be considered a less-invasive surgical method than traditional abdominal surgery. This study was aimed at evaluating and adapting the general coelioscopic principles of the technique to teleosts (10 European eels [ Anguilla anguilla ]). All the examined fish were anaesthetized with tricaine methanesulfonate solution. The coelioscopic procedures were performed with a rigid, 30° offset, 1.9-mm diameter endoscope connected to a portable video system. The results confirm that coelioscopy represents an imaging technique with high sensitivity in evaluating the coelomic organs in European eels.

Summary The host-parasite relationship between bogue (Boops boops) and Cerathotoa parallela (Isopoda: Cymothoidae) was studied in the Southern Tyrrhenian Sea (overall prevalence of isopods in the area, age-dependent and sex-dependent prevalence). Yearly prevalence ranged from 1.0% in March to 10.7% in October, with a positive correlation between prevalence and mean sea surface temperatures (SST), highest values being related to the period of increasing SST. The first four age-classes were parasitized, with prevalence decreasing according to the age of the host. The relationship between total length (TL) and total weight (TW) was examined in infested and non-infested specimens of the same age whereby slight differences were detected, i.e. at a given length non-infested specimens weighed more than infested fishes. The parasite occurred throughout the study area with wide fluctuations in prevalence, from 0 to 36.4%, the values being higher in the eastern part of the study area. C. parallela parasitize the bogue Boops boops in a manner that does not constitute a serious threat to the life of the host.

The abundance, occurrence, biological features, growth and mortality parameters of the thornback ray, Raja clavata L. 1758 (Rajformes, Rajidae), coming from two contiguous areas of the Strait of Sicily (Central Mediterranean Sea) were analysed in order to discriminate the stocks. The two investigated areas include bottoms off southern Sicily (I-G16) and bottoms further at large (O-G16). The density indexes, biomass indexes and occurrences were substantially lower in I-G16 than O-G16. On the contrary, the biological traits were more similar, although significant differences were detected in the sex ratio, in the median total length of all specimens, in the length frequency distribution, in the estimated maximum length and in the female length-weight slope parameter. The median length of fully mature specimens did not significantly differ between the two areas. The von Bertalanffy’s asymptotic length and the ratio of total mortality/von Bertalanffy’s curvature parameter suggest a total mortality higher in the I-G16 than the O-G16 populations. This article supports the hypothesis that the investigated populations, in spite of a similar original life cycle, have evolved in two distinct unit stocks as a consequence of the different fishing efforts and the low-intermingling rate between the two areas.

Summary In this paper the host-parasite relationship between Philometra filiformis and the common pandora Pagellus erythrinus from the Southern Tyrrhenian Sea were studied. A total of 305 (257 females and 48 males) specimens of common pandora were sampled from June 2009 to April 2011 from commercial landings as well as from bottom trawl surveys. A total of 39 P. erythrinus were parasitized (mean prevalence, P = 12.80%; mean abundance, A = 0.19), with the parasite occurring throughout the study area and with wide fluctuations in prevalence values ranging from 0 to 28.60%. Prevalence increased with age of the host, with most parasites (27.78%) found in the older common pandora whereby P. filiformis parasitized only the females. A significant correlation between prevalence, abundance and maturity stages of the fish was evident, with most parasites found in mature/spawning specimens. The varying degrees of gonadic damage caused by this nematode reveal a serious threat to the reproductive success of P. erythrinus.

Objective—To validate the use of radiography to determine the length of sagittal otoliths in intact bogue (Boops boops; a sparid fish [commonly called sea bream]). Sample—52 bogue cadavers. Procedures—Weight and standard lengths (from the tip of the snout to the caudal end of the last vertebra) of fish were measured. The radiographic beam was centered over the postorbital area, and images were obtained via ventrodorsal, 30° right dorsal–left ventral oblique, and 30° left dorsal–right ventral oblique projections. Otoliths were removed from the fish; sagittae were measured directly and on radiographic images by use of a vernier caliper. The relationship between direct and radiographic measurements of sagittal otoliths was calculated. Results—Paired sagittal, lapillus, and asteriscus otoliths were identified. Sagittal otoliths were comma-shaped on ventrodorsal projections; in oblique projections, they appeared ovoid and pairs of otoliths were located in the same dorsal plane. Radiographic length of sagittal otoliths was significantly correlated with directly measured length, and radiographic measurements were not significantly different between ventrodorsal and oblique radiographic projections. Conclusions and Clinical Relevance—Radiographic examination of sagittae was useful to determine the length of sagittal otoliths and, consequently, the fish length. In ecological applications, the radiographic measurement of sagittal otolith length may be useful for studies on the aquatic diet of organisms (fish, pinnipeds, and marine birds) because it allows for quick back-calculation to the size of prey.

The occurrence and bathymetric distribution of the squid Illex coindetii (Cephalopoda: Ommastrephidae) in the southern Tyrrhenian Sea (Central Mediterranean) was assessed using trawl survey data collected from 1994 to 2007 as part of the MEDITS Project. The study area covered approximately 7256 km 2 , with depths of 10–800 m. The highest mean values for density and biomass indices for I. coindetti were obtained in the 101–200 m stratum. At this depth range, the highest density and biomass values occurred in 1998 (1121 N/km 2 ) and in 2003 (42.52 kg/km 2 ), respectively. A cartographic presentation of the mean biomass and density values showed that the species had a wide bathymetric distribution (35–600 m), although the bulk of the catch occurred in the 70–180 m depth range. I. coindetii were characterised by a very wide size range, with the dorsal mantle length (DML) varying between 25 and 300 mm. The length classes of the specimens ranged from 25 to 120 mm for immature and from 60 to 210 mm and from 65 to 300 mm for males and females, respectively. Recruits were collected in all surveys and were distributed at depths of more than 50 m, although the highest values were recorded in the 101–200 m stratum. The logistic fits of the proportions of both the mature specimens and all specimens together resulted in an overall L m50% of 150 and 105 mm for females and males, respectively. The spatial distribution of I. coindetii indicated that the species was more abundant along the Calabrian coasts, while the recruits were concentrated in the eastern part of the study area (Cape Vaticano, Calabria). The results of this study highlight the need for a more comprehensive study of both environmental processes affecting the abundance and distribution of I. coindetii and the life history of the species in the southern Tyrrhenian Sea in order to improve our understanding of the species’ dynamics in relation to environmental variability.

The blue-mouth, Helicolenus dactylopterus dactylopterus (Delaroche, 1809) (Pisces: Scorpaenidae), is a scorpionfish widespread in the whole Mediterranean basin, where it plays an important ecological role in deep-sea fish communities. The depauperation of this large-size sedentary and slow-growing fish can be an index of overexploitation. This species is found throughout all Italian seas; the juveniles are mainly located around 150-300 m depth, whereas the adult specimens are spread over a wider depth range from 200 m to as deep as 1000 m. The abundance in number and weight, the spatial distribution, the population structure, the growth and the recruitment pattern of H. dactylopterus were analysed in this study. The present paper integrates data from 11 bottom trawl surveys carried out in the Southern Tyrrhenian Sea (Central Mediterranean) along Calabrian and Sicilian coasts, within the framework of the MEDITS Project. A total of 1412 specimens of H. dactylopterus weighting 20.051 kg were caught. The species appeared in 40% of the 296 hauls analysed, throughout the whole depth range surveyed. The highest values of frequency of occurrence (>67%) were obtained in the slope, whereas in the shelf they fell to around 16%. On the continental shelf the species was found between 106 and 196 m depth, and in the slope between 400 and 645 m. The highest mean density index (N . km(-2)) value was obtained in the 100-200 m depth stratum, whereas the highest mean biomass index (kg . km(-2)) value was recorded in the deeper 200-500 m stratum. The length distribution of the specimens ranged between 2.5 and 24.5 cm. From the Von Bertalanffy growth model the following parameters for the whole population were obtained: L(infinity): 30 cm; K: 0.16 year(-1); t(0): -0.02. The sampled population is composed mainly of the young-of-the-year fraction, which can reach up to 98% of the whole catch. Recruits (age 0+) and juveniles (age up 4 years) are limited to waters shallower than 500 m, whereas adults are present below this depth.

Previous studies on fish and marine mammals support the hypothesis that marine species harbor antibiotic resistance and therefore may serve as reservoirs for anti biotic-resistance genetic determinants. The aim of this study was to assess the resistance to antimicrobial agents of Gram negative strains isolated from loggerhead sea turtles (Caretta caretta). Oral and cloacal swabs from 19 live-stranded loggerhead sea turtles, with hooks fixed into the gut, were analyzed. The antimicrobial resistance of the isolates to 31 antibiotics was assessed using the disk-diffusion method. Conventional biochemical tests identified Citrobacter spp., Proteus spp., Enterobacter spp., Escherichia spp., Providencia spp., Morganella spp., Pantoea spp., Pseudomonas spp. and Shewanella spp. Highest prevalences of resistance was detected to carbenicillin (100%), cephalothin (92.6%), oxytetracycline (81.3%) and amoxicillin (77.8%). The isolates showing resistance to the widest range of antibiotics were identified as Citrobacter freundii, Proteus vulgaris, Providencia rettgeri and Pseudomonas aeruginosa. In this study, antibiotic resistant bacteria reflect marine contamination by polluted effluents and C. caretta is considered a bioindicator which can be used as a monitor for pollution.

The cloacal microbial flora of 49 loggerhead sea turtles, Caretta caretta, was evaluated from two cloacal swabs for each individual. The predominant isolates in descending order of frequency were as follows: Escherichia coli (78 isolates), Proteus mirabilis and Proteus vulgaris (24 isolates), Citrobacter freundii (15 isolates), Providencia rettgeri (9 isolates) and Enterobacter sakazakii (6 isolates). This study provides data on cloacal microflora of loggerhead sea turtles impacted by hook and line fishery interactions, that may be useful for comparison with healthy sea turtles and with sea turtles affected by other conditions or exposed to other environmental conditions.

Effects of formalin preservation on eye lens of bogue, Boops boops (Linnaeus, 1758): comparison of direct (post-fixation) vs ultrasound (true) measurements By F. Macr i, A. Passantino, S. Di Pietro, D. Ruscica, A. Sfacteria, C. De Stefano and T. Bottari Department of Veterinary Sciences, University of Messina, Polo Universitario Annunziata, Messina, Italy; Institute for Coastal Marine Environment, National Research Council, Messina, Italy

In this study, 45 (10 whole specimens and 35 frozen claws) frozen samples of Portunus pelagicus imported into Sicily (Italy) from the west coast of Africa were examined to assess their bacteriological characteristics and suitability for consumption. Bacteriological examination was performed on two subsamples for each whole crab. The first was the body and claw muscle; the second was a pool of viscera and gills. In the case of frozen claws, each muscle claw was a sample. An aerobic plate count at 30 degrees C (mesophilic aerobic plate count [MAPC]) and 18 degrees C (psychrotrophic aerobic plate count [PAPC]) for 3 days, sulfite-reducing anaerobes, total coliforms, Escherichia coli, enterococci, and Aeromonas spp. were enumerated. Detection of halophilic Vibrio spp. was also performed using salt polymixin broth as an enrichment medium and thiosulfate citrate bile salts sucrose agar as a selective medium; a further morphological and biochemical identification of suspected colonies was performed. The bacterial load of muscle and viscera and gills was low. The MAPC ranged from 0.78 to 3.26 log CFU/g, and the PAPC ranged from 0.48 to 2.41 log CFU/g. Vibrio spp., Aeromonas spp., sulfite-reducing anaerobes, and E. coli were never isolated from muscles or viscera and gills. In contrast to the findings of others, this study showed good bacteriological quality of crabs imported into Sicily from the west coast of Africa. This study also demonstrated the positive influence of the characteristics of environment of origin and postharvest handling hygiene; these parameters could be useful in the context of the application of the hazard analysis critical control point system to this production.

Over a 5 yr period, severe infestations due to Gnathia vorax larvae affecting different teleosts have been registered at the Civic Aquarium of Messina, Italy. Here, the damage caused by these parasites is evaluated from a macroscopical and histopathological point of view. We also attempt to evaluate the amount of blood sucked up by a single parasite and make some observations about the haematophagia. The histopathological changes confirm mucosal electrolytic failure as the main problem, even though the mean value of blood sucked up by a single parasite, about 1.9 mg, suggests that haematophagia may play an important role in the pathogenesis of such infestation. In conclusion, it was found that the G. vorax larvae caused 2-fold damage that was responsible for the death of the fish. Little by little, the parasitic problem was successfully removed by washing the tank, using fresh water rather than costly and dangerous chemotherapeutans.