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This two-year study evaluates the effects of new management strategies directed at helping the recovery of Adriatic cuttlefish populations. The ability of three specially developed artificial spawning devices–seagrass collectors (SC; deployed on artificial reefs), longline collectors (LC; deployed at mussel farms), and trap collectors (TC; delivered to 19 professional and 54 recreational trap fishermen together with a dedicated logbook)–to attract egg deposition was tested. All devices were provided with a polyethylene floating rope 8 mm in diameter that served as a collector for egg deposition. Total rope length was 1,440 m in SC (2,880 segments of 0.5 m), 250 m in LC (500 segments of 0.5 m), and 250 m in TC (10 m per trap). Although the sites where SC and LC were deployed were sheltered from the action of destructive fishing gears, heavy winter storms destroyed the SC after a year. Most recreational fishermen and none of the professional fishermen provided detailed information on percent egg coverage on their collectors. The collectors attached to the three devices proved highly suitable for cuttlefish spawning, collecting more than 500,000 eggs on 2,440 m of rope. The analysis of egg diameter distribution suggested three laying events during the spawning season. The logbook data showed that egg number peaked in June. The present approach, combining habitat reconstruction and participatory research, has the potential to contribute to the recovery of cuttlefish stocks in the framework of a broader management plan. [ABSTRACT FROM AUTHOR]

The expected increase in global food demand, as a consequence of a rising and wealthier world population, and an awareness of the limits and drawbacks of modern agriculture, has resulted in a growing attention to the potential of the seas and oceans to produce more food. The capture production of presently exploited marine fish stocks and other species has more or less reached its maximum and can only be slightly improved by better management. This leaves four alternative options open to increase marine food production: (1) manipulating the entire food web structure via removal of high trophic level species to allow an increasing exploitation of low trophic level species, (2) harvesting so far unexploited stocks, such as various fish species from the mesopelagic zone of the ocean or the larger zooplankton species from polar regions, (3) low‐trophic mariculture of seaweeds and herbivorous animals, and (4) restoration of impoverished coastal ecosystems or artificially increasing productivity by ecological engineering. In this paper, we discuss these four options and pay attention to missing scientific knowledge needed to assess their sustainability. To assess sustainability, it is a prerequisite to establish robust definitions and assessments of the biological carrying capacity of the systems, but it is also necessary to evaluate broader socio‐economic and governance sustainability. [ABSTRACT FROM AUTHOR]

Abstract: The potential impact of a suspended mussel farm on the coastal macrobenthic communities of the Western Adriatic Sea was seasonally evaluated through a multi-control sampling strategy over 1 year. Both univariate biological indices and multivariate analysis indicated that the variations of benthic macrofauna were mainly due to seasonality rather than location of the sampling sites in respect to the farm, and that the main species contributors were common to most sites and seasons. Most of these species are known as indicators of organic enrichment and/or pioneer species in recolonization of defaunated bottoms and commonly occur in the macrobenthic populations inhabiting the seabed of the North-Central Adriatic Sea between 12 and 15 m depth. Only the different abundances of filter- and deposit-feeders gave some evidence of a limited, spatial influence on the culture in the surroundings. The external sites showed a significant difference compared to the reference sites (ANOSIM: R =0.395, P =0.5). The overall results suggest that open-sea mussel culture has minimal detrimental effects on the zoobenthic communities of the Western Adriatic Sea that are usually in an immature stage due to subsequent environmental and anthropogenic disturbances. Although one-year study might not be sufficient to evaluate the effects of mussel culture, the results of this work represent a useful tool for the monitoring of the potential environmental impact of mussel farms to ensure the sustainable development of shellfish culture in the Italian shallow coastal waters. [Copyright &y& Elsevier]

The article discusses the role played by the Senigallia, Italy artificial reef in the northern Adriatic Sea in terms of the feeding behavior of three common fishes. Studies show that what these fishes feed is similar to those living in manmade structures, surrounding soft bottom, inside and outside the reef and even at an open&mdashsea control suite. The artificial structure provided these three common fishes the main source of food and the link with the reef declined from.

Fishery discard survival depends on multiple conditions; caution is essential when survival study outputs are employed to support management decisions. The study presents a stepwise procedure, devised to estimate discard survival, that accounts for the variability characterizing commercial fishing practices. The procedure was applied to the first survival study performed onboard rapido trawlers targeting Solea solea in the Mediterranean Sea. Undersized specimens collected during sorting were assessed for vitality; some were retained for captive observation. The main drivers affecting discard survival at the time of catch sorting (immediate survival) were identified and used to outline four different operational conditions set (scenarios). Immediate survival in each scenario was subsequently modified by applying a hazard coefficient of survival after 5 days of captive observation in relation to each vitality class, thus obtaining relative survival estimates following discarding. Temperature and air exposure duration were found to exert a major effect on survival, with catch weight and seabed type being additional important factors. The relative survival rate showed an aggregate value of 22.9% (10.5–33.4%). Scenario approach can enhance our understanding of the stressors influencing discard survival. The outcomes are discussed to explore the potential applications of the procedure to the identification of mitigation strategies. [ABSTRACT FROM AUTHOR]

Atomic force microscopy (AFM) is a consolidated technique for the study of biological systems, usually ex vivo or in culture, under different experimental conditions. Yet, the diffusion of the technique in the scientific context of histology is still rather slow and limited. In the present work, we demonstrate the potential of AFM, in terms of morphological and nanomechanical imaging, to study the effects of nano‐ and micro‐sized metallic pollutants in living biological systems. As a model, we investigated marine molluscs (Mytilus galloprovincialis) grown in the Adriatic Sea. We characterized histological sections from two organs (gonads and digestive glands) of molluscs collected during several surveys at different growth time and distance from gas extraction platforms. We evaluated the effects of nano‐pollutants mostly on the local tissue structure by combining AFM microscopy with scanning electron microscopy (SEM). Furthermore, the AFM images allowed evidencing the presence of nano‐ or micro‐sized structures that exhibit different nanomechanical properties compared to the rest of the tissue. The results demonstrate how coupling AFM and SEM analysis can provide an effective procedure to evaluate the morphological alterations produced by the exposure to exogenous nano‐pollutants in tissue and constitute a promising way to reveal basic mechanisms mediating the cytotoxicity of specific exogenous pollutants ingested by edible organisms. [ABSTRACT FROM AUTHOR]

Alive specimens belonging to Tellimya tenella (Lovén, 1846) were recorded for the first time in Adriatic Sea. Up to date, only few pleistocene fossils or empty valves of this species had been reported in Italian waters. [ABSTRACT FROM AUTHOR]

The observation of a new species in a new area represents the first opportunity to follow and study the dynamics of colonization and understand how a new species arrives, what are its movements and its potential impact. The discovery of a large number of species outside their usual area of distribution is probably the most important reason for the increase in perceived biodiversity of the Adriatic ichthyofauna. A total of 4 specimens of T. picturatus were caught in the period MayJune 2011 in the surroundings of an offshore gas platform in the Northern Adriatic Sea. Scientific literature depicts this species as rare in the Adriatic Sea, indicating and suggesting the Pomo Pit (Central Adriatic Sea) as the Northern latitudinal limit of its distribution. On this basis, this paper reports the first record of T. picturatus in the Northern Adriatic basin, suggesting an expansion of its spatial distribution. [ABSTRACT FROM AUTHOR]

Paradiopatra bihanica (Intes & Le Loeuff, 1975) (Polychaeta, Onuphidae) is reported for the first time in the Adriatic Sea. In this study the morphological characters of the observed individuals are provided, as well as the extension of its hitherto geographical distribution. [ABSTRACT FROM AUTHOR]

Fishing of Nassarius mutabilis is by far the most important activity carried out by artisanal fisheries in the central and northern Adriatic Sea, accounting for more than 35% of total fishing effort and yielding from 2000 to 3000 t of landings each year. This gastropod is targeted from the beginning of autumn to the end of spring using basket traps. Despite its importance under a socioeconomic point of view, the scientific studies on the biology and ecology of this species are very scarce and the failure of the current management measures could also be attributed to the scarce knowledge on the biology of this species in the area. Taking this statement into consideration, the results of the present study contribute to fill a few existing gaps and may be useful to improve the management measures currently in force. Samples were collected from March 2006- March 2008 during monthly fishing surveys and carried out using basket traps in the central Adriatic Sea. A total of 383 males (size range 7-29 mm SH) and 504 females (size range 15-32 mm SH) were caught. Mean SH (± SD) of males was 15.84±3.57 mm and mean SH of females was 25.31±3.06 mm. A significant difference in the biometric characteristics between the two sexes was discovered. The condition index (CI) showed similar seasonal trends for both sexes, with a decrease from late winter to spring followed by an increase from summer to fall - early winter. The minimum values were recorded in summer and the maximum ones in winter, following an opposite trend in respect to water temperature. In the males this trend was observed starting from size classes larger than 11 mm SH, hence this size might be very close to the size at first sexual maturity. The size at first maturity hypothesized for females (16-20 mm SH) agrees with the minimum landing size (MLS) currently established for this species (20 mm SH). The absence of small females (SH < 15 mm) and large males (SH > 23 mm) leads to suppose a sex reversal from male to female at around 20 mm SH. On this basis, the management measure of MLS leads to the selective retention of females and, hence, to a sexual gap between the two sexes with possible consequences on the biology of the species and the resilience of the stock. The peaks of CI observed for males and females confirmed that the spawning season of this gastropod occurs in late winter - early spring, according to the abundant presence of egg capsules attached to submerged substrates in that period at sea. Consequently, from a management point of view, it would be advisable to shorten the fishing season that at present extends from fall to later spring. [ABSTRACT FROM AUTHOR]

Experimental fishing trials were carried out on an Italian commercial vessel to test gillnets of different monofilament diameters targeting common sole ( Solea solea ). The gillnets only differed in the nominal monofilament diameter: 0.18, 0.20, 0.22, 0.25, and 0.30 mm. The nominal mesh size (stretched) was 72 mm. A total of 47 taxa were caught. The mean number of species caught with 0.30 mm monofilament was significantly lower than those obtained with the three thinnest diameters. Total number, number of commercial and discard of non-commercial species significantly decreased with the increase of monofilament diameter. The number of common sole and tub gurnard caught was not statistically different amongst diameters. No statistical differences were observed for the length–frequency distributions of common sole and tub gurnard caught with the different monofilament diameters. The analysis of the mechanism of capture for the common sole showed that for all diameters the main type of retention was snagging, and the percentage of individuals retained in such way decreased with the increase of diameters, while an opposite trend was observed for the common sole that were gilled. Monofilament thickness had a substantial effect upon the catch rates of the gillnets. [ABSTRACT FROM AUTHOR]

Different marine and coastal activities have diverse economic, environmental, and socio-cultural objectives, which can lead to conflict when these multidimensional activities coincide spatially or temporally. This is sometimes driven by a lack of understanding or other users' needs and consequentially adequate planning and the utilization of a common language is essential. By using a transparent approach based on multi-criteria analysis, we characterize and establish priorities for future development/conservation for all users in the coastal area using six representative European Case Studies with different levels of complexity. Results varied according to location, but significantly it was found that stakeholders tended to favour ecological and social over economic objectives. This paper outlines the methodology employed, the results derived, and the potential for this approach to reduce conflict in coastal and marine waters. [ABSTRACT FROM PUBLISHER]

Abstract: The northern and central Adriatic Sea represents an important spawning and aggregation area for common sole (Solea solea) and provides for around 20% of the Mediterranean landings. In this area, this resource is mainly exploited with rapido trawl and set nets. The stock is not yet depleted and faces a situation of growth overfishing. The comparison between the spatial distribution by age of S. solea and the geographic patterns of the rapido trawl fishing effort evidenced an overlapping of this fishing activity with the area where juveniles concentrate (age groups 0–2). The majority of spawners inhabits specific offshore areas, here defined as ‘sole sanctuaries’, where high concentrations of debris and benthic communities make difficult trawling with rapido. The aim of this study was to evaluate existing spatial management regimes and potential new spatial and temporal closures in the northern and central Adriatic Sea using a simple modelling tool. Two spatial simulations were carried out in order to verify the effectiveness of complementary methods for the management of fisheries: the ban of rapido trawling from October to December within 6nautical miles and 9nautical miles of the Italian coast. The focus of the simulation is that the effort of the rapido trawl is moved far from the coast during key sole recruitment periods, when the juveniles are moving from the inshore nursery area toward the offshore feeding grounds. The management scenarios showed that a change in selectivity would lead to a clear increase in the spawning stock biomass and an increase in landings of S. solea in the medium-term. The rapido trawl activity could be managed by using a different logic, bearing in mind that catches and incomes would increase with small changes in the spatial pattern of the fishing effort. The present study highlights the importance of taking into account spatial dimensions of fishing fleets and the possible interactions that can occur between fleets and target species, facilitating the development of control measures to achieve a healthy balance between stock exploitation and socio-economic factors. [Copyright &y& Elsevier]

Abstract: The common sole (Solea solea) is one of the most important demersal resources in the northern and central Adriatic Sea (GFCM GSA 17). Landings from this basin make up around 23% of the overall Mediterranean and Black Sea production. Despite the economic relevance of sole in the Adriatic Sea, and its inherent property of being shared among three countries (i.e. Italy, Slovenia and Croatia), studies on its spatial distribution are scarce and aged. Therefore, the aim of the present study was to assess the spatial distribution and investigate the dynamics of this species in the GSA 17. Samples of common sole were collected in the framework of yearly rapido trawl surveys (SoleMon), during late autumn, from 2005 to 2010, i.e. the spawning season of common sole in the Adriatic. Results highlighted that juveniles are mostly concentrated in shallow water (0–30m depth) along the Italian coast and their spatial distribution persisted along the sampled years. By contrast adults were mainly distributed in the central/eastern part of the basin at depths >30m. As a result of the different spatial distributions, juveniles are exploited exclusively by Italian vessels, especially by beam trawlers (i.e. rapido trawl), while adults are caught by Croatian and Slovenian fishing fleets in their respective national waters and by the Italian fleet operating in international waters. These results, while shedding light on the common sole spatial ecology in the Adriatic, represent crucial information for the setting of international collaboration for a rational spatial-based management of the resource. [Copyright &y& Elsevier]

Abstract: The main goals of this project were to evaluate if artificial reefs are suitable sites for releasing hatchery-reared sea bass and if intensively and extensive large-volume cultured sea bass are suitable to be released into the wild for stock enhancement purposes. Large-volume cultured bass were reared in lower densities compared to intensively cultured ones and, when fry were about 90days old, were transferred into external ponds connected to the channels of the surrounding marsh, where that they could integrate pellet food sources with live prey. Intensively cultured bass were fed for 55days with Artemia salina (Linnaeus, 1758) and then with pellets. Underwater visual census (UVC) and fishing sampling were carried out to verify the presence of the tagged specimens at the artificial reef. A low mortality rate after tagging was observed and good tag retention was recorded. Individuals dead after tagging were statistically smaller than survivors. A total of 45 tagged bass (42 large-volume and 3 intensively cultured) were returned by fishers and 16 specimens were observed during UVC (15 large-volume and 1 intensively cultured). The majority of recaptured bass concentrated in the surroundings of river mouths and harbours suggesting that, after release, sea bass migrated towards shallower and brackish waters. Subsequently, as they grew, they came back towards deeper waters and tended to aggregate around artificial structures. Analysis of stomach contents of returned individuals confirmed their dependence on hard-substrate food items. The study provides evidence to support the suitability of large-volume juveniles for restocking purposes, due to their ability to prey on wild food and their endurance to the stress caused by release operations. [ABSTRACT FROM AUTHOR]

Abstract: The macrozoobenthos living around two offshore gas platforms, Barbara NW (pB) and Calipso (pC) located in the northwestern Adriatic Sea were investigated for three years after their construction to detect eventual effects due to the platforms. The sampling stations were spaced at increasing distance from the platforms up to 1000 m. Both multivariate and univariate analysis showed an initial defaunation (short-term effect) at pB and within a 120 m radius at pC. A general recovery in terms of abundance, species richness and diversity was observed for the benthic communities after one year. During the third monitoring year a mussel mound developed at both the platforms (longer-term effect) extending up to 30 m from pC, whereas similar soft-bottom communities were found at all the other distances. The geographical position plays an important role in the “timing” of the above effects. Moreover, despite the different environmental features, a 3-year monitoring plan can be effective to evaluate the potential impact on benthic communities of offshore gas platforms in the north-central Adriatic Sea. [ABSTRACT FROM AUTHOR]

Abstract: Size selectivity of basket traps for changeable nassa (Nassarius mutabilis) was estimated through comparative fishing trials with traps varying in mesh size and net colour. Selectivity curves of two commercial (19mm white twine and 19mm black twine) and three experimental (23, 26 and 28mm white twine) traps were estimated using SELECT method. In addition, theoretical size-selectivity curves were calculated from morphometric data using a simplified version of Sechin method. Differing from the opinion of fishermen, N. mutabilis did not show any preference for dark coloured twine. Retention curves estimated with SELECT method had a very sharp selectivity and well fitted catch data in all cases. Theoretical size-selectivity curves were very close to size-selectivity curves obtained from experimental data. The two types of curve were very similar in shape, although the theoretical ones were shifted towards larger size classes and showed a slightly steeper slope than SELECT curves. The mesh size commonly used by fishermen is not adequate for rationally exploiting the resource, as catches mainly included undersized specimens, whilst the 23 and 26mm mesh sizes would represent a good compromise between reduced occurrence of undersized individuals and satisfactory yields of commercial product. [Copyright &y& Elsevier]

Multibeam echosounders are widely used for 3D bathymetric mapping, and increasingly for water column studies. However, they rapidly collect huge volumes of data, which poses a challenge for water column data processing that is often still manual and time-consuming, or affected by low efficiency and high false detection rates if automated. This research describes a comprehensive and reproducible workflow that improves efficiency and reliability of target detection and classification, by calculating metrics for target cross-sections using a commercial software before feeding into a feature-based semi-supervised machine learning framework. The method is tested with data collected from an uncalibrated multibeam echosounder around an offshore gas platform in the Adriatic Sea. It resulted in more-efficient target detection, and, although uncertainties regarding user labelled training data need to be underlined, an accuracy of 98% in target classification was reached by using a final pre-trained stacking ensemble model. [ABSTRACT FROM AUTHOR]

Research on abundance and composition of fish assemblages surrounding offshore extraction platforms is essential to evaluate their impact as well as to understand relationships between natural and artificial habitats. Also decommissioning practice, which belongs to the lifecycle of these structures, can be encouraged or discouraged if fish school behaviour in the close proximity of the platform is well understood. With thousands of platforms to be decommissioned around the world in coming decades, understanding such dynamic interactions is key to improve spatial management of marine ecosystems. In this context, this study drafts a work plan that can be used to investigate fish presence and abundance, school movement and qualitative species composition around a platform over long time periods. It integrates fishing captures, multibeam echosounder (MBES) investigations, and drop camera shootings to overcome the limitations of the individual methods. Monthly samplings were conducted at a three-leg gas extraction platform placed at ~80 m depth in the central Adriatic Sea, for one year after its installation. MBES completely insonified the studied area, providing data on school shape, volume, surface area and position throughout the water column. Fishing captures were useful for MBES targets' identification by measuring the presence/abundance of nekto-benthic and pelagic species both in the nearby of the structure and in the open sea, while drop camera shootings added evidence of a few species in close proximity to the poles, which were not censused by the other methods. Results underlined the strong attraction exerted by the platform and the significant influence of the explanatory variable distance on the schools' nominal volume. • The study investigates fish behaviour at an offshore gas platform in the Adriatic Sea. • Monitoring approach integrating fishing captures, MBES surveys, and drop camera shootings. • Species abundances and school features change mostly with distance. • Platforms' impact on fish assemblage should be identified before planning decommissioning. [ABSTRACT FROM AUTHOR]

Hydrocarbon seepage is overlooked in the marine environment, mostly due to the lack of high-resolution exploration data. This contribution is about the set-up of a relocatable and cost-effective monitoring system, which was tested on two seepages in the Central Adriatic Sea. The two case studies are an oil spill at a water depth of 10 m and scattered biogenic methane seeps at a water depth of 84 m. Gas plumes in the water column were detected with a multibeam system, tightened to sub-seafloor seismic reflection data. Dissolved benthic fluxes of nutrients, metals and Dissolved Inorganic Carbon (DIC) were measured by in situ deployment of a benthic chamber, which was used also for the first time to collect water samples for hydrocarbons characterization. In addition, the concentration of polycyclic aromatic hydrocarbons, as well as major and trace elements were analyzed to provide an estimate of hydrocarbon contamination in the surrounding sediment and to make further inferences on the petroleum system. [ABSTRACT FROM AUTHOR]