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Abstract: A Dynamic Energy Budget (DEB) model is used to simulate growth and reproduction of the shellfish Mytilus galloprovincialis and Crassostrea gigas in an integrated multi-trophic aquaculture (IMTA) farm scenario situated in the Southern Mediterranean (the Gulf of Castellammare, Sicily). We modelled the effect of primary production enrichment at fish cages on shellfish growth and life history traits using 4years-hourly temperature data (01 January 2006–31 December 2009) at a depth of 1m. Outputs of the DEB simulations were: the maximum theoretical total shell length of shellfish, the potential reproductive outputs and the mean annual von Bertalanffy growth rate. There was a mean increase in empirically measured suspended chlorophyll-a of approximately 45% close (within about 100m) to fish cages (2.3±1.1μgl−1) compared to sites away (about 1.5km) from the cages (1.3±0.6μgl−1). DEB simulations using localised CHL-a measures showed that mussels close to cages could reach greater maximum length at the end of 4th year than those far from cages and in open-sea. Simulations of oyster growth close to cage sites resulted in double growth rate (12cm in 4years) compared to oysters at far sites (6.5cm in 4years). The present study improves knowledge of the application of DEB models to predict the potential fitness of shellfish starting from First Principles. This is an innovative approach with potential for application at larger scales than those of local facilities. [Copyright &y& Elsevier]

Diet composition, feeding rhythm, gastric evacuation rate and daily ration were investigated in juvenile Mullus surmuletus (Linneo 1758). Fish were collected in the lagoon of the Stagnone di Marsala in western Sicily, in July 1995, during a 24 h sampling period. Copepoda, Polychaeta, Amphipoda and Tanaidacea were shown to be the most frequent prey items. The feeding index values showed two different daily feeding times. A unimodal trend in the daily rhythm of food consumption was derived, with a peak in feeding between 1200 and 2000 h. Gastric evacuation in juvenile M. surmuletus is best described by an exponential model, with a gastric evacuation rate R = 0.66 g h-1 (r = 0.88) (T = 24.45 ± 0.64°C). The amount of food consumed daily, calculated according to the Elliott and Persson model, was 0.079 g, equal to about 8% of the average dry weight of the fish. [ABSTRACT FROM AUTHOR]

Fish assemblages associated with offshore platforms were surveyed using two underwater visual census techniques: strip transects and mobile point counts. Data were collected from four depth ranges at three platforms off Crotone, Italy (Ionian Sea). A total of 25 fish species belonging to 12 families were recorded for the three platforms. Significant differences between sampling methods and depth were observed in the fish assemblage structure, species richness and fish abundance. The mean number of species recorded with the strip transect method was always greater than that obtained with mobile point counts, whilst the opposite pattern was observed for mean abundances. Gregarious species such as Boops boops, Chromis chromis, Anthias anthias and Oblada melanura were responsible for most of the differences in the assemblage structure. According to our results, both methods allowed us to observe species that are not usually caught by means of fishing gear. When both census techniques are used, they provide complementary information about the fish assemblages strictly associated with the platform structures. [ABSTRACT FROM AUTHOR]

From the beginning of March 2020 and for the following two and half months, many European countries comprising Italy have been forced into an unprecedented lockdown, allowing only the opening of essential economic activities needed to address the problems created by the pandemic (e.g. sanitary, food provision). Like many sectors of the Italian economy, aquaculture has also slowed down due to the ongoing emergency and the consequent closure of business. In our study we provided a 'snapshot' of the socio-economic effects of the lockdown on the aquaculture sector in Italy, immediately following the adoption of the COVID-19 restrictions as they were perceived by the workers. Although it was surveyed for a short-time period, differences in perception have been detected both in relation to the type of aquaculture as well as to the geographic locations where farms were placed, partially reflecting the economic gaps already existing within the northern and the southern part of the country before the lockdown. • COVID-19 pandemic have triggered cascade effects on all components of the food supply chain. • Cultural and structural disparities in Italy seem to affect the differences in aquaculture farmers' perceptions. • The knowledge of the effects of the COVID-19 and multiple stressors are crucial to generate useful indications. [ABSTRACT FROM AUTHOR]

The volume of boat traffic and its potential connection to the coastal distribution of the common bottlenose dolphin (Tursiops truncatus) was evaluated off Lampedusa Island (Strait of Sicily). From July to September 2006 daily surveys were carried out at eight sites along the coast, three times a day, to assess the number, type, and size of boats moving, fishing, or stationed in Lampedusa waters. The study area was divided into four geographic areas: northwest, northeast, southwest, and southeast. Data were analyzed to determine the difference in the number of boats among the areas, sampling months, and times of day. The presence of dolphins was monitored by standardized land-based observations. Dolphins (n = 139) from 38 sightings were observed throughout the study period (90 days). In order to compare the presence of dolphins among areas, a relative abundance index was used: A-EH (number of sighted specimens per effort hour). Common bottlenose dolphins appeared to be broadly distributed around Lampedusa, although this study highlighted a possible overlap between their habitat, boat traffic, and fishery, especially in the southwest. [ABSTRACT FROM AUTHOR]

Among marine ecosystems globally, those in the Mediterranean Sea, are facing many threats. New technologies are crucial for enhancing our understanding of marine habitats and ecosystems, which can be complex and resource-intensive to analyse using traditional techniques. We tested, for the first time, an integrated multi-platform approach for mapping the coastal benthic habitat in the Civitavecchia (northern Latium, Italy) coastal area. This approach includes the use of an Unmanned Surface Vehicle (USV), a Remote Operated Vehicle (ROV), and in situ measurements of ecosystem functionality. The echosounder data allowed us to reconstruct the distribution of bottom types, as well as the canopy height and coverage of the seagrass Posidonia oceanica. Our study further involved assessing the respiration (Rd) and net primary production (NCP) rates of P. oceanica and its associated community through in situ benthic chamber incubation. By combining these findings with the results of USV surveys, we were able to develop a preliminary spatial distribution model for P. oceanica primary production (PP-SDM). The P. oceanica PP-SDM was applied between the depths of 8 and 10 m in the studied area and the obtained results showed similarities with other sites in the Mediterranean Sea. Though in the early stages, our results highlight the significance of multi-platform observation data for a thorough exploration of marine ecosystems, emphasizing their utility in forecasting biogeochemical processes in the marine environment., (© 2024. The Author(s).)

The two invasive blue crabs, Callinectes sapidus and Portunus segnis have spread rapidly in the Mediterranean and no data exists on the connectivity of populations. Determining the source and recruitment areas is crucial to prioritize where population control measures should be put into immediate action. We simulated the dispersal of blue crab larvae using a Lagrangian model coupled at high resolution to estimate the potential connectivity of blue crab populations over a 3-year period. Our results reveal that the main areas at risk are the Spanish, French, Italian Tyrrhenian and Sardinian coasts for Callinectes sapidus with high populations connectivity. Tunisia and Egypt represent high auto recruitment zones for Portunus segnis restricted to the central and western basins. This study provides an overview of the connectivity between populations and will help define priority areas that require the urgent implementation of management measures., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Expected temperature rise and seawater pH decrease may affect marine organism fitness. By a transplant experiment involving air-temperature manipulation along a natural CO 2 gradient, we investigated the effects of high pCO 2 (~1100 μatm) and elevated temperature (up to +2 °C than ambient conditions) on the reproductive success, recruitment, growth, shell chemical composition and oxygen consumption of the early life stages of the intertidal reef-building vermetid Dendropoma cristatum. Reproductive success was predominantly affected by temperature increase, with encapsulated embryos exhibiting higher survival in control than elevated temperature conditions, which were in turn unaffected by altered seawater pH levels. Decreasing pH (alone or in combination with temperature) significantly affected the shell growth and shell chemical composition of both embryos and recruits. Elevated temperatures along with lower pH led to decreases of ~30% oxygen consumption and ~60% recruitment. Our results suggest that the early life stages of the reef-builder D. cristatum are highly sensitive to expected environmental change, with major consequences on the intertidal vermetid reefs they build and indirectly on the high biodiversity levels they support., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Over the last 35 years, at both the European and the Italian level, great efforts have been made to increase the number of Marine Protected Areas (MPAs): they are considered an effective tool for protecting oceans and biodiversity. In recent years, MPAs have become more than simply tools to improve marine conservation. In fact, their management agencies are actively involved in the sustainable development of nearby communities through the promotion of recreational activities (boating, snorkeling, diving). Even if the recreational uses of the marine environment are generally considered benign, they can potentially be highly detrimental for species and their habitats. As a result, these activities should be controlled through the spatial zoning and the regulation of the MPAs. Thus, the achievement of the conservation goals of the MPAs depends primarily on compliance with the regulations of recreational uses inside their boundaries. The objective of this study was to estimate boating usage and the related level of compliance inside the Capo Gallo and Isola delle Femmine (Italy) MPA. The spatial and temporal trend of boating and the behaviors of boaters were measured through direct observation over a period of 2 summer months. The study highlighted a weakness in the effectiveness of this MPA, linked to a social component and compliance with the regulation. Solutions for effective management plans are outlined thanks to an understanding of the limitations and potential of existing MPA policies. Integr Environ Assess Manag 2019;00:1-13. © 2019 SETAC., (© 2019 SETAC.)