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Mugil cephalus has been identified as a suitable species for feeding populations in developing countries, and it represents a traditionally harvested and consumed species in various European countries. A decline in wild populations and a growing demand have promoted new interest in mullet production in hatcheries, considered imperative for the production of a steady supply of fry and the expansion of M. cephalus aquaculture. In the present study, wild adults collected in Sardinian lagoons were induced to spawn during their natural reproductive period by treating them with a single dose of a slow release GnRHa preparation (200 µg kg bw-1). In 2016, a protocol for reducing stress in capturing, transporting and selecting wild adults was set up, and 64% of the females with an oocyte diameter larger than 550 µm were successfully induced to spawn. Five spawning induction trials were carried out in the period 2016–2019. The mean fertilization rate and the mean hatching rate obtained were 83 ± 14% and 76 ± 13%, respectively. The individuals obtained were reared indoor in a recirculating aquaculture system (RAS) at a density of 40 individuals L-1 for 60 days, and their survival ranged from 10 ± 2 to 19 ± 1%. During the whole larval rearing phase, from 0 to 34 days post hatching (dph), the mean standard growth rates recorded were 5.0 ± 0.7% in total length and 14.4 ± 3.9% in body weight. The rearing density used resulted in an average survival rate comparable or even better than those obtained by other authors, thus indicating the possibility of producing M. cephalus fries in captivity from sexually mature adults captured in Sardinian lagoons, reducing the costs and optimizing the production.

This study discusses the potential impact of removing Posidonia banquette on the sediment budget of a siliciclastic-sediment-starved beach-barrier system. The morphology as well as the sediment volumes of this system were estimated. The banquette’s composition and sediment content were determined with samples collected during five sampling campaigns conducted in one year. The carbonate content of the system was estimated by analyzing three 1 m long cores collected along the barrier. Five digital terrain models from DGPS surveys were used to compute the beach’s average morphology to estimate the sediment volumes. The carbonate and siliciclastic sediment content from the cores were used to calculate the overall beach’s sediment mass. Total sediment mass accounted for 126,000 m3, of which ca. 86% was siliciclastic quartz sand and approximately 14% was carbonate sediment. Total banquette deposition during the year accounted for 2300 m3, with a maximum and averaged sediment content of 339 kg m3 and 78 kg m−3. A permanent loss of ca. 1.31% of total mass will occur if 5000 m3 of banquette were to be removed. In such beach settings, banquette removal may limit sediment availability, reducing the overall sediment mass and decreasing beach resilience against climate change effects such as sea level rise.

Hypoxia and petrogenic hydrocarbon contamination are two anthropogenic stressors that coexist in coastal environments. Although studies have estimated the impact of each stressor separately, few investigations have assessed the effects of these stressors in interaction. We therefore investigated the impact of these combined stressors on sea bass, (Dicentrarchus labrax) physiology. After experimental contamination with physically dispersed oil, fish were exposed to hypoxia or normoxia, and active/standard metabolic rates (AMR and SMR, respectively), and metabolic scope (MS) were estimated. At the protocol's end, the uptake of polycyclic aromatic hydrocarbons (PAHs) was estimated by evaluating relative concentrations of bile metabolites. In terms of bile metabolites, our results validated the uptake of PAHs by contaminated fish in our experimental settings, and further suggest that the hypoxic period after contamination does not reduce or increase compound metabolization processes. Our data showed significant effects of hypoxia on all metabolic rates: a significant drastic AMR reduction and significant SMR diminution led to decreased MS. We also found that oil contamination significantly impacted AMR and MS, but not SMR. These results suggested that when evaluated separately, hypoxia or oil affect the metabolic rate of sea bass. On the other hand, when evaluated in combination, no cumulative effects were observed, since fish exposed to both stressors did not show a stronger impact on metabolism than fish exposed to hypoxia alone. This suggests that oil impacts fish metabolism when fish occupy normoxic waters, and that oil does not magnify hypoxia-induced effects on fish metabolism.

Hydrocarbons contamination and hypoxia are two stressors that can coexist in coastal ecosystems. At present, few studies evaluated the combined impact of these stressors on fish physiology and behavior. Here, we tested the effect of the combination of hypoxia and petrogenic hydrocarbons on the anti-predator locomotor performance of fish. Specifically, two groups of European sea bass (Dicentrarchus labrax) were exposed to clean water (Ctrl) or oil-contaminated water (Oil). Subsequently, fish of both groups were placed in normoxic (norx) or hypoxic (hyp) experimental tanks (i.e. four groups of fish were formed: Ctrl norx, Ctrl hyp, Oil norx, Oil hyp). In these tanks, escape response 2 was elicited by a mechano-acoustic stimulus and recorded with a high speed camera. Several variables were analyzed: escape response duration, responsiveness (percentage of fish responding to the stimulation), latency (time taken by the fish to initiate a response), directionality (defined as away or toward the stimulus), distance-time variables (such as speed and acceleration), maneuverability variables (such as turning rate), escape trajectory (angle of flight) and distancing of the fish from the stimulus. Results revealed (i) effects of stressors (Ctrl hyp, Oil norx and Oil hyp) on the directionality; (ii) effects of Oil norx and Oil hyp on maneuverability and (iii) effects of Oil hyp on distancing. These results suggest that individual stressors could alter the escape response of fish and that their combination could strengthen these effects. Such an impact could decrease the probability of prey escape success. By investigating the effects of hydrocarbons (and the interaction with hypoxia) on the anti-predator behavior of fish, this work increases our understanding of the biological impact of oil spill. Additionally, the results of this study are of interest for oil spill impact evaluation and also for developing new ecotoxicological tools of ecological significance.

In this paper the problem of the optimisation of at-sea campaigns is tackled throughout the implementation of a near real-time decision support system (DSS) for short-term Lagrangian observing platforms. The DSS consisted of two modules: a real-time coastal-ocean forecasting system (CFS), including both hydrodynamic and particle-tracking numerical models, and a module to provide optimised deployment solutions for a set of Lagrangian current-meter buoys. The system was calibrated for a shallow water environment – the Cabras Lagoon in the western Mediterranean Sea. The DSS was then applied to provide in situ optimised measurement strategies during a Lagrangian survey campaign. The different solutions provided by the DSS were verified by real-time measurements and the system was established to be efficient in reducing the cost–benefit ratio and favouring long records and near-synoptic and non-redundant observations.

International audience; Temperature is an important factor for fish. Yet, little is known about its effects on the feeding behavior of fish and the subsequent consequences of these behavioral changes on the spatial distribution of resources. We analyzed the differences in the feeding behavior of two sizes of juvenile Liza aurata at two water temperatures (i.e. 10°C and 20°C), using laboratory mesocosms. We also examined whether temperature-induced changes in feeding behavior of the smaller size of L. aurata would affect the spatial distribution of the microphytobenthos (MPB) biomass, an important resource in coastal systems. Both the number of feeding events and the swimming velocity during feeding in juvenile L. aurata were higher at 20°C than at 10°C, independently of the fish size. The time spent feeding did not vary between 10°C and 20°C, while the distance covered during feeding was significantly smaller at 20°C than at 10°C. Grazing did not affect the mean MPB biomass, but did increase its spatial variance at the smaller scale (i.e. a few centimeters) at 20°C. A high number of feeding events, a high swimming velocity during feeding and a small distance covered during feeding in 20°C-acclimated L. aurata most likely represented an adaptation to an increase in metabolism, as well as to the need to reduce the energy costs of feeding at 20°C. Results also indicated that changes in feeding behavior of the 20°C-acclimated L. aurata were responsible for the increase in small-scale spatial variability in the MPB biomass. We suggested that the enhanced spatial patchiness due to grazing by fish at 20°C might yield a local increase in the mean MPB biomass, probably increasing photosynthetic efficiency of cells and algal growth that counterbalance the negative effect of algal removal by fish, and resulting in the lack of an overall significant effect on the mean.

Pinna nobilis is the largest endemic bivalve of the Mediterranean Sea, declared protected since 1992. Although hydrodynamic stress induced by waves is known to influence density, size and orientation of P. nobilis , the effect of other hydrological features is unknown. This paper considers a P. nobilis population living within a Posidonia oceanica meadow in the Gulf of Oristano (Sardinia, Italy). We hypothesize that spatial differences in density and orientation of P. nobilis may be related to significant wave height (H S ), wave direction (D W ), bottom current direction (D BC ) and bottom current speed (S BC ). A population of P. nobilis was investigated at different sites and its distribution was correlated to hydrodynamics by means of a numerical modeling approach. The spatial distribution was patchy, with a density of 0.06–6.7 ind. 100 m − 2 . A non-uniform distribution of shell orientations (O S ) was demonstrated in 4 sites out of 6. D BC and S BC were the main factors affecting O S , while waves had little influence. A S BC of 0.07 m s − 1 appears to be the threshold for inducing specimen directionality with shells aligned to the current and the ventral side exposed to the flow. This suggests that feeding strategy is a key factor in determining O S , in addition to drag minimization. We also highlighted the role of adjacent lagoons in supporting high densities as a result of high food availability. These findings demonstrate the usefulness of modeling techniques in explaining the spatial distribution pattern of P. nobilis and in contributing to our knowledge of its ecological traits.

At the end of May, 17 scientists involved in an EU COST Action on Conservation Physiology of Marine Fishes met in Oristano, Sardinia, to discuss how physiology can be better used in modelling tools to aid in management of marine ecosystems. Current modelling approaches incorporate physiology to different extents, ranging from no explicit consideration to detailed physiological mechanisms, and across scales from a single fish to global fishery resources. Biologists from different sub-disciplines are collaborating to rise to the challenge of projecting future changes in distribution and productivity, assessing risks for local populations, or predicting and mitigating the spread of invasive species.

This work deals with the spatial characteristics of the wind fields evaluated from synthetic aperture radar (SAR) images and simulated by the weather research and forecasting (WRF) atmospheric model in the Gulf of Oristano, a small coastal area about 10 km × 18 km wide in western coast of Sardinia (Western Mediterranean Sea). The SAR11 derived wind fields have been obtained analyzing images of the COSMO-SkyMed, Radarsat-2, and Sentinel-1A satellites through a fully two-dimensional continuous wavelet transform (2-D-CWT) method. The analysis of the wind directions has shown that the model variability is limited if compared to that inferred by 2-D-CWT method, which mostly respects the variability evidenced by in situ data. As the use of model directions to compute the SAR wind fields is a standard in many studies, the impact on the SAR wind speed retrieval of using the model instead of the SAR20 derived directions has been assessed: differences of wind speed greater than ±10% occur for about the 20% of data. The spatial variability of the SAR and model wind speed fields results quite different at both local and domain scales. The knowledge of the spatial variations of the surface wind fields can be very important for the oceanographic applications and constitutes the added value brought by SAR in the description of the coastal wind. For this rea27 son, the SAR-derived wind fields should be taken as reference in many kind of applications.

Deliverable 1.3 provides inventory of legal regulations, initiatives, developed projects and technologies having potential influence on sensors design processes. Report focus on possible integration of monitoring requirements by other EU and national legislation. Structure of the report consist of: 1.Inventory of EU directives bringing legal regulations providing requirements for having potential influence on sensors design and measurement methodology in reference to parameters demanded, spatial and temporal resolution of data and availability of information for potential users, 2.Inventory of conventions adopted by European Countries, approaching to reach and keep Good Environmental Status, having impact on monitoring processes and fostering development of technical infrastructure, 3.Analysis of national legislation implementing EU directives and representing approach to develop appropriate infrastructure for monitoring duties 4.Inventory of projects developing technologies having potential influence on sensors design, measurement and monitoring methodologies. 5.Inventory of innovative technologies, initiatives and ongoing policy developing processes as source of requirements for perspective technology development These identified items are drivers of new technologies development processes. Sensors, as a part of bigger systems and infrastructures interoperating each other have to conform regulations formulated in legal acts in the context of parameters measured, condition of operation, interaction with environment as object of examination, transmission protocols and data collections terminating data acquisition, processing, storage and information extraction and exchange processes. Objectives The objective of the report is to provide inventory of regulations, directive and conventions having potential influence on sensors design, measurement and monitoring methodologies development having potential influence on sensors design processes. Rationale New developments in the field of technology, measurement and monitoring methodologies, policy and law regulations, possibilities and demands for integration of monitoring requirements by other EU and national legislation, and interoperability challenges are factors determining perspectives of sensors development. Report on regulations, directive and conventions having potential influence on sensors design will include the analysis of possibilities of integration sensor's functionality to meet monitoring requirements and to help to distinguish sensitive or vulnerable areas where monitoring is necessary according to identified ecosystem properties.

Global increase in sea temperatures has been suggested to facilitate the incoming and spread of tropical invaders. Here, we determined the effect of temperature on the aerobic metabolic scope of two competing fish species, one native and one invasive, and we predicted their future thermal habitat suitability., Global increase in sea temperatures has been suggested to facilitate the incoming and spread of tropical invaders. The increasing success of these species may be related to their higher physiological performance compared with indigenous ones. Here, we determined the effect of temperature on the aerobic metabolic scope (MS) of two herbivorous fish species that occupy a similar ecological niche in the Mediterranean Sea: the native salema (Sarpa salpa) and the invasive marbled spinefoot (Siganus rivulatus). Our results demonstrate a large difference in the optimal temperature for aerobic scope between the salema (21.8°C) and the marbled spinefoot (29.1°C), highlighting the importance of temperature in determining the energy availability and, potentially, the distribution patterns of the two species. A modelling approach based on a present-day projection and a future scenario for oceanographic conditions was used to make predictions about the thermal habitat suitability (THS, an index based on the relationship between MS and temperature) of the two species, both at the basin level (the whole Mediterranean Sea) and at the regional level (the Sicilian Channel, a key area for the inflow of invasive species from the Eastern to the Western Mediterranean Sea). For the present-day projection, our basin-scale model shows higher THS of the marbled spinefoot than the salema in the Eastern compared with the Western Mediterranean Sea. However, by 2050, the THS of the marbled spinefoot is predicted to increase throughout the whole Mediterranean Sea, causing its westward expansion. Nevertheless, the regional-scale model suggests that the future thermal conditions of Western Sicily will remain relatively unsuitable for the invasive species and could act as a barrier for its spread westward. We suggest that metabolic scope can be used as a tool to evaluate the potential invasiveness of alien species and the resilience to global warming of native species.

Deliverable 1.4 is aimed at identification of existing and operable observing systems and sensors which are relevant to COMMON SENSE objectives. Report aggregates information on existing observing initiatives, programmes, systems, platforms and sensors. The Report includes: oinventory of previous and current EU funded projects. Some of the them, even if started before 2007, were aimed at activities which are relevant or in line with those stemming from MSFD in 2008. The 'granulation' of the contents and objectives of the projects varies from sensors development through observation methodologies to monitoring strategies, oinventory of research infrastructure in Europe. It starts from an attempt to define of Marine Research Infrastructure, as there is not a single definition of Research Infrastructure (RI) or of Marine Research Infrastructure (MRI), and there are different ways to categorise them. The chapter gives the categorization of the MRI, together with detailed description and examples of MRI - research platforms, marine data systems, research sites and laboratories with respect of four MSFD descriptors relevant to COMMON SENSE project, otwo chapters on Research Programs and Infrastructure Networks; the pan-European initiatives aimed at cooperation and efficient use of infrastructural resources for marine observation and monitoring and data exchange are analysed. The detailed description of observing sensors and system are presented as well as frameworks for cooperation, oinformation on platforms (research vessels) available to the Project for testing developed sensors and systems. Platforms are available and operating in all three regions of interest to the project (Mediterranean, North Sea, Baltic), oannexed detailed description of two world-wide observation networks and systems. These systems are excellent examples of added value offered by integrated systems of ocean observation (from data to knowledge) and how they work in practice. Report concludes that it is seen a shortage of new classes of sensors to fulfil the emerging monitoring needs. Sensors proposed to be developed by COMMON SENSE project shall answer to the needs stemmed from introduction of MSFD and GES descriptors.

Con il termine morfodinamica costiera si intende il reciproco adattamento della topografia e della idrodinamica in seguito al trasporto dei sedimenti (Masselink e Hughes, 2003). Questo concetto è applicato da alcuni decenni allo studio dei sistemi costieri e, in particolare, dei litorali sabbiosi, per inquadrare in un unico schema concettuale le complesse relazioni, e le relative retroazioni, esistenti tra le forzanti meteo-marine (onde e correnti, venti), la morfologia delle spiagge, il trasporto dei sedimenti, la stratigrafia e la variabilità di questi sistemi in diversi intervalli temporali. L'approccio morfodinamico ha portato alla realizzazione di diversi schemi classificativi delle spiagge, come ad esempio il modello di classificazione proposto da Wright e Short (1984), che risultano utili per definire con pochi indicatori sintetici i processi prevalenti e le morfologie presenti in un determinato sistema di spiaggia. Tali indicatori e sistemi di classificazione, limitati alle spiagge sabbiose, sono stati applicati principalmente a spiagge extramediterranee. Nel caso dei litorali Mediterranei, in particolare nelle aree caratterizzate da una geomorfologia costiera articolata, anche altri fattori concorrono all'assetto morfologico dei litorali sabbiosi e alla sua variabilità temporale. Tali fattori comprendono, tra l'altro, la morfologia del substrato e le biocenosi costiere. Nel presente capitolo si riporta lo studio svolto sulla baia di San Giovanni del Sinis (Cabras, Oristano), nell'ambito del progetto ResMar, tra il 2012 e il 2013, e realizzato in collaborazione tra l' Istituto per l'Ambiente Marino e Costiero del Consiglio Nazionale delle Ricerche di Oristano, il Dipartimento di Ingegneria Civile, Ingegneria Ambientale e Architettura dell'Università di Cagliari e l'Area Marina Protetta Penisola del Sinis Isola di Mal di Ventre (Cabras, Oristano).