Search Results (328)

Fisheries management in the Mediterranean Sea faces persistent challenges due to the prevalence of data-poor and data-limited stocks, small-scale multi-species fisheries, and limited long-term monitoring programs. Effective assessment methodologies are critical to ensuring sustainable exploitation, yet traditional data-rich stock assessment models remain infeasible for many Mediterranean fisheries. This review provides a comprehensive synthesis of current methodologies developed and applied to assess data-poor fisheries in the Mediterranean context. We examine catch-only approaches, length-based methods, empirical indicators, and multi-indicator frameworks increasingly adopted by the General Fisheries Commission for the Mediterranean (GFCM) and the EU’s Data Collection Framework (DCF). Special attention is given to case studies from the western, central, and eastern Mediterranean that demonstrate the opportunities and limitations of these approaches. We further explore emerging tools, including integrated modeling frameworks, simulation-based harvest control rules, and participatory approaches involving fishers’ local knowledge, to highlight innovations suited to mixed, small-scale Mediterranean fisheries. The review concludes by identifying key gaps in data collection, assessment capacity, and institutional coordination, and proposes a roadmap for improving data-poor fisheries management under Mediterranean-specific ecological, socio-economic, and governance constraints. By consolidating methodological advances and practical lessons, this review aims to provide a reference framework for researchers, managers, and policymakers seeking to design robust, adaptive strategies for sustainable fisheries management in data-limited Mediterranean contexts. Full article

The effect of desert dust intrusion on the detection of marine heatwaves (MHWs) has not been discussed in previous publications. In this study we investigated this effect in the Eastern Mediterranean (EM) by separate use of microwave (MW) and infrared (IR) satellite radiometry of nighttime sea surface temperature (SST); they are represented by the SST-MW and SST-IR datasets. For the first time, our analysis provides observational evidence that there was no effect of dust intrusion on the detection of MHWs by SST-MW, when aerosol optical depth (AOD) ranged within an extremely wide interval of 0.3 to 5. In contrast to SST-MW, in the presence of strong dust intrusion (AOD of up to 5), SST-IR was incapable of detecting MHWs. We found an inverse correspondence between daily variations in both SST-IR and AOD. The inverse correspondence indicates that SST-IR was profoundly influenced by desert dust, causing erroneous daily variations in SST-IR. This prevented the detection of MHWs. An essential point of our study is that even in the presence of weak dust intrusion (AOD ranged from 0.3 to 0.4) SST-IR was incapable of detecting MHWs due to the occurrence of erroneous short-term sharp drops in SST-IR. This was because of dust appearance at high altitudes. Our findings highlight that the SST-IR’s incapability to detect MHWs (in the presence of dust intrusion) led to an underestimation of the presence of MHWs by the SST datasets which integrate MW and IR radiometry, i.e. the Multiscale Ultrahigh Resolution (MUR) Global Foundation SST analysis. Full article

In recent decades, the Mediterranean Sea has been experiencing faunal changes associated with the impact of biological invasions resulting from the influx of invasive alien species (IAS). During the CNR-ISMAR Carg0222 oceanographic cruise, Mimosina affinis, a benthic foraminifera species of Indo-Pacific origin previously reported in more eastern sectors of the Mediterranean, was detected in the Tyrrhenian Sea, at the seafloor off the Italian coast. The study of benthic foraminiferal assemblages, conducted along with sedimentological analysis of seafloor deposits, allowed to reconstruct the distribution of Mimosina affinis in the investigated area and define its relationship with seabed characteristics. The species is commonly found in samples collected at a water depth not shallower than nine metres, showing a preference for silty fine sand sediments. The abundance of the species, in terms of relative abundance, is higher in biocoenoses than in thanatocoenoses, suggesting that the species is established and actively spreading in the studied area. Full article

Since the 1970s, Tunisia has been a popular destination due to its diverse natural environment and a tourist offer based on recreation 3S (Sea–Sun–Sand). Tourist flow is therefore concentrated along its eastern Mediterranean coast, where there is a risk of overtourism. One of the proposed solutions to prevent this phenomenon is to assess the natural potential and tourism functions of Tunisia in the context of sustainable tourism. This goal was achieved through the use of the method of multidimensional comparative analysis, which allowed for a measurable comparison of the country’s tourist regions in terms of 23 characteristics illustrating the potential and functions of nature-based attractions and accommodation facilities (number of beds, number of tourists using accommodation). In light of the synthetic indicators obtained, the greatest threat to sustainable nature-based tourism was identified in the regions of Nabeul–Hammamet and Yasmine–Hammamet, as well as Monastir–Skanes. In the first region, this results from the large number of tourists visiting natural attractions, whereas in the second, it stems from the excessive number of people using accommodation facilities. Therefore, it is necessary to monitor tourist flow and take various measures to relieve pressure on these regions. Full article

The European squid Loligo vulgaris inhabits the continental shelf of the North and Central Atlantic and the Mediterranean Sea, with significant socio-economic value for the associated fisheries. Globally, the stock appears to be maintained at levels close to the optimal sustainable yield, but capture statistics indicate high fluctuations in fisheries production, and some regions might be affected by overexploitation. In this study, we used the mitochondrial marker mtCOI to investigate temporal and spatial genetic structure and variability in the European squid in the eastern part of the Adriatic Sea and put it into context with its Mediterranean and Atlantic conspecifics using data from public databases. High haplotype and low nuclear diversity of mtCOI were detected, with no significant genetic differentiation, suggesting one panmictic homogeneous population in the North and Central Adriatic Sea. The Adriatic cluster appears to diverge from its Mediterranean–Atlantic conspecifics; however, this pattern should be considered preliminary due to the limited and uneven geographic sampling available in public databases. The current dataset lacks comprehensive coverage of several Mediterranean sub-basins, which restricts the resolution of connectivity patterns and may mask subtle population structure. Despite these limitations, our results provide an important baseline for understanding the L. vulgaris Adriatic stock and for developing joint management policies among all countries that exploit this shared resource. Full article

Microsporidia are a group of obligate intracellular parasites with a broad host range. These parasites can cause mild to severe harm to their hosts, making them important targets for research. However, studies on common wild-caught fish from the Atlantic Eastern Central Zone (FAO Area 34) remain scarce. 576 individuals across 35 fish species from this region were collected from local markets between 2011 and 2019. The specimens were dissected, and lesions were examined using histology, wet mounts, PCR, and transmission electron microscopy. However, microsporidian infection was detected only in round sardinella (Sardinella (S.) aurita), with 19 out of 39 individuals infected. Parasitized fish weighed nearly half as much as non-infected ones, indicating a potentially significant economic impact. Molecular and ultrastructural analyses identified the parasite as Glugea (G.) thunni, a species previously reported only from the Mediterranean Sea. This study provides the first record of G. thunni in FAO Area 34, with round sardinella likely serving as its primary host. This and other closely related sequences may represent a single taxonomic entity or, more likely, a complex of a few cryptic species geographically separated across the Mediterranean Sea and the eastern and western North Atlantic regions. Full article

Coralligenous assemblages are among the most diverse habitats of the Mediterranean Sea, yet those of the north-eastern basin remain understudied despite their vulnerability to human impacts and climate change. We applied a multimodal underwater sensing approach to map coralligenous formations, assess gorgonian populations and evaluate the effects of marine litter in a conservation-priority area (NE Aegean Sea, Greece). Side-scan sonar enabled seafloor mapping and guided targeted Remotely Operated Vehicle (ROV) surveys. ROV-based distance sampling and imagery provided quantitative data on Eunicella cavolini and Paramuricea clavata, including density, size structure, and injuries, alongside systematic documentation of marine litter. Gorgonians formed monospecific ecological facies, segregated by location—P. clavata occurred deeper than E. cavolini. Densities were low (E. cavolini: 0.35 colonies m⁻², P. clavata: 1.46 colonies m⁻²) and small colonies (<10 cm) were rare, suggesting limited recruitment. However, the presence of large colonies indicates stable environmental conditions that support long-term persistence, as reproductive output increases with colony size. Colony injuries were minor, but marine litter was abundant, dominated by fishing lines and ropes entangled with gorgonians and sponges. These findings highlight the value of acoustic–optical integration for non-destructive monitoring and provide essential baselines for conservation under EU directives. Full article

This study conducts a diagnostic analysis of an extremely heavy rainfall event and its causative factors that occurred in Libya, North Africa on 10 September 2023. The Weather Research and Forecasting (WRF) model was also employed to perform some sensitivity experiments for this heavy rainfall event and further reveal its causes. Results indicate that the primary synoptic system responsible for this extreme precipitation event was an extratropical cyclone (storm) named “Daniel”. During the formation and development of this cyclone, the circulation at the 500 hPa level from the eastern Atlantic to western Asia exhibited a stable “two troughs and one ridge” pattern, with a upper-level cold vortex over the eastern Atlantic, a high-pressure ridge over central Europe, and a cut-off low over western Asia, collectively facilitating the formation and development of this cyclone. As this cyclone moved southward, it absorbed substantial energy from the Mediterranean Sea; following landfall, the intrusion of weak cold air enabled the cyclone to continue intensifying. Meanwhile, the northwest low-level jet stream to the west of the extratropical cyclone moved alongside the cyclone to the coastal regions of northeastern Libya, where it converged with water vapor transport belts originating from the Ionian Sea, the Aegean Sea, and the coastal waters of northeastern Libya. This convergence provided abundant water vapor for the rainstorm event, and under the combined effects of convergence and orographic lifting on the windward slopes of the coastal mountains, extreme precipitation was generated. In addition, the atmosphere over the coastal regions of northeastern Libya exhibited strong stratification instability, which was conducive to the occurrence of extreme heavy precipitation. Although WRF successfully reproduced the precipitation process, the precipitation amount was underestimated. Sensitivity experiments revealed that both the topography in the precipitation area and the sea surface temperature (SST) of the Mediterranean Sea contributed to this extreme heavy precipitation event. Full article

The origin of humans on Earth is closely linked to understanding how ancient populations dispersed into adjacent territories. Traditionally, studies have identified landscape and climatic changes as the primary factors in this dispersal. However, we propose that regional tectonic and geodynamic factors also played a significant role in shaping these movements. To analyze this phenomenon, we employed several primary methods, including radiometric dating, magnetostratigraphy, paleomagnetic correlation, isotope–oxygen analysis, tectonothermal studies, gravity mapping, paleobiogeographic assessment, lithofacies analysis, and event and cyclic stratigraphy. Our research indicates that the Akchagylian hydrospheric maximum, which reached up to +200 m, significantly limited the early dispersal of hominins from Africa to Eurasia. The migration corridor was shaped by tectonic activity between the Dead Sea Transform and the boundary of the Mesozoic Terrane Belt carbonate platform. We argue that, during the early stages of hominin evolution in East Africa, the Levantine Corridor (LC) had not yet developed into an optimal route for dispersal, either tectonically or paleogeographically. Suitable habitats for early hominins emerged only after the regression at the end of the Middle Gelasian, around two million years ago, when sea level fell by approximately 200 m, leading to the dissection of the coastal high plateau of the Eastern Mediterranean. We therefore suggest that the LC became established only after the termination of the Akchagylian transgression and the subsequent landscape reconfiguration of the Eastern Mediterranean. Our integrated analysis, combining paleomagnetic, structural, tectonic, and event stratigraphy data, indicates that the age of the renowned ‘Ubeidiya site in northern Israel is several thousand years older than previously thought. This paleogeographic impact had not been considered in earlier studies. Considering the diverse and complex factors that governed hominin dispersal from Africa into Eurasia within this multifaceted region, we propose that the scope of research should be broadened. Our detailed study of the Carmel area, located northeast of the Levantine Corridor and influenced by it during the Pleistocene, indicates that this region was inundated during the early phases of hominin migration out of Eastern Africa. Besides this, we have conducted an integrated geological–geophysical landscape analysis of the central part of the Israeli coastal plain. Full article

Centrostephanus longispinus (Philippi, 1845) is a sea urchin widely distributed across the tropical and temperate Atlantic Ocean (including the Caribbean) and Mediterranean Sea. Although it is present along the Alboran Sea coastline (Western Mediterranean), it is generally considered rare and is listed under conservation and protection lists and conventions due to fragmented populations threatened by seabed degradation. This study provides the first density and size distribution data for this echinoid in the circalittoral and bathyal bottoms of the Alboran Sea, aiming to relate its presence to seabed features, environmental variables, and human pressures. A series of 131 (62 ROV and 69 TASIFE transects) underwater image transects were collected during CIRCAESAL expeditions (2021, 2023, 2024) using a ROV and a photogrammetric sledge from infralittoral to bathyal bottoms (17–856 m depth). Images were processed with OFOP software to quantify and classify individuals by size classes, depth, substrate, seafloor roughness, micro-habitat, and coverage of key benthic structuring species. A total of 524 individuals of C. longispinus were detected in 13 transects, with the highest densities recorded at 48–100 m depths in rough, rocky substrates with crevices and a moderate to low coverage of key benthic structuring species. Differences in habitat use were also observed across depth strata: individuals in shallower zones tend to remain hidden within crevices and structurally complex substrates, displaying a more cryptic behaviour, whereas those in deeper strata rely less on refuge and occupy less complex habitats. The largest aggregations occurred near the Guadiaro Canyon, outside the “Estrecho Oriental” Special Area of Conservation (SAC), suggesting this area may serve as a population reservoir deserving conservation. Despite these findings, ecological knowledge of C. longispinus remains limited, and future studies should improve the knowledge gaps, particularly in the eastern and southern Alboran Sea. Full article

Etesian winds, the characteristic summer winds over large parts of Greece and the eastern Mediterranean, can cause coastal upwelling, especially over the eastern Aegean. The question that many studies address is whether these northern winds can cause upwelling processes that alter not only sea surface temperature but also chlorophyll concentrations, which are indicative of phytoplankton growth and overall ocean health. The present study is an effort to investigate the above matter over the eastern Aegean, from Lesvos to Ikaria and Samos islands, on a monthly basis, based on all the available satellite chlorophyll data up to now. Full article

Over the past decade, increasing attention has been given to the impacts of anthropogenic microparticle (AM) pollution on marine ecosystems. This study investigates AM ingestion in three commercially important fish species—Sparus aurata Linnaeus, 1758, Dicentrarchus labrax Linnaeus, 1758, and Boops boops Linnaeus, 1758—collected from both wild and farmed populations in Greek marine and lagoon environments. A total of 60 specimens were sampled from the Messolonghi Lagoon, Rhodes Island, and the Cyclades. AM were detected in 61.7% of the individuals analyzed. The mean number of ingested items per individual was 1.1 ± 1.2 in B. boops, 1.0 ± 1.7 in wild and 2.3 ± 2.1 in farmed S. aurata, and 2.5 ± 3.1 in wild and 3.6 ± 2.2 in farmed D. labrax. Ingestion ranged from 0 to 9 items per fish. No significant correlations were found between fish size and either the number or the size of ingested AM in any species. The ingested AM were primarily classified as fibers and fragments, displaying variability in size and color. Black was the dominant color across all species, followed by red and blue, while yellow was rarely observed. A statistically significant difference in the mean size of AM was recorded between wild and farmed D. labrax, whereas no such difference was observed for S. aurata. Overall, these findings provide new evidence on AM contamination in seafood species and highlight their occurrence in both natural and aquaculture environments of the eastern Mediterranean. Full article

Sharks play critical roles in marine ecosystems as apex or mesopredators, regulating trophic dynamics and ecosystem stability. However, their populations are increasingly threatened due to overexploitation caused by targeted fisheries, bycatch, and illegal activities. This study investigates the feeding ecology and reproductive biology of the shark species Mustelus mustelus, which has been heavily fished across the Mediterranean, leading to significant population declines. A total of 333 specimens were collected between October 2019 and October 2022 from Türkiye’s Aegean Sea, Sea of Marmara, and Levantine Sea coasts. The total lengths of the specimens ranged from 42.1 to 173.0 cm, with an average of 73.5 cm ± 26.8, and their weights ranged from 205 to 22,470 g, with an average of 1840.2 g ± 2525.5. Stomach content analyses revealed that M. mustelus is a benthic predator with a broad diet. Regional and size-based comparisons indicated that crustaceans were the primary food source, followed by teleost fish and mollusks. Ontogenetic dietary shifts were evident, with juveniles feeding predominantly on crustaceans, while adults consumed more teleost fish and mollusca. The reproductive biology analysis showed placental viviparity in M. mustelus, with the smallest observed mature male measuring 75 cm TL and the smallest observed pregnant female measuring 96 cm TL. The uterine fecundity of pregnant females ranged from 8 to 29 embryos. Additionally, the pupping season of M. mustelus in the Aegean Sea was found to occur in March and April. M. mustelus populations have declined dramatically in the western Mediterranean and in many other parts of their range. The scarcity of data on this species in the eastern Mediterranean basin, including Türkiye, is noteworthy. Therefore, this study investigated the populations in the study area from a bioecological perspective and provides fundamental data to support the development of conservation strategies for the species. Full article

This study examines the evolution of a beach formed along the coastline of a semi-enclosed, essentially tideless, embayment in the eastern Mediterranean Sea. The analysis revealed that the primary factors influencing its recent evolution are the terrestrial sediment influxes, current nearshore oceanographic conditions, and the existence of coastal constructions. The beach zone is exposed to waves approaching from the south with extreme values of height and period of 7 m and 4.3 s, respectively. Associated morphodynamic characteristics include a closure depth of 7 m, a breaking depth of 4.3 m, and a maximum run-up of 2.4 m. Since the mid-1900s, the shoreline has evolved through an accretional phase from 1960 to 1988, followed by a retreating phase from 1989 to 1997, except in the central part, where progradation has continued. The most recent period (1998–2017) has been relatively stable, though with a slight retreating trend. During storm events, changes to the beach are not uniform along-shore. Gross estimates of beach retreat due to sea level rise induced by climate change threaten the existence of the entire beach (for moderate and extreme IPCC Special Report Emissions Scenarios); however, this does not seem to be the case if riverine sediment influx continues. Full article

The Eastern Mediterranean Sea has become a hotspot for biological invasions, with thermophilic species like Lagocephalus sceleratus (silver-cheeked toadfish) and Pterois miles (devil firefish) posing significant ecological and socioeconomic threats. Machine learning models (support vector machine and neural network) were developed to predict species establishment, demonstrating high predictive accuracy. SHapley Additive exPlanations analyses further highlighted the relative influence of environmental predictors. Nominal logistic regression identified bottom temperature and salinity as the key environmental drivers for the establishment of these species, with thresholds of 16.38 °C and 39.14 psu for P. miles and 15.84 °C and 39.09 psu for L. sceleratus. Forecasts through 2035, generated using the Prophet model, have predicted warming bottom temperatures but declining salinity levels, creating variable conditions for invasion. Long-term suitability was assessed by comparing forecasted conditions against thresholds, revealing that salinity and chlorophyll a consistently fall below suitable levels for both species. L. sceleratus showed stable suitability with occasional declines, while P. miles exhibited greater variability. These findings underscore the importance of fine-scale benthic data and integrated modeling approaches for early detection and adaptive management of invasive species in Mediterranean ecosystems. The study provides clear thresholds to guide ongoing environmental monitoring and emphasizes the need for continuous assessments to anticipate future invasion risks under changing climatic conditions. Full article