A review on the biodiversity of hard substrate invertebrate communities in the Aegean Sea

This review attempts to estimate the biodiversity of the macrobenthic communities that develop on hard bottoms in the Aegean Sea. Literature analysis revealed that 1,171 species inhabit the hard substrate communities, constituting 20.9% of the total Mediterranean species. The hierarchical cluster analysis of the available data identified five major types: (1) the supralittoral communities, (2) the midlittoral communities, (3) the port communities, (4) the various facies of the photophilic algae community, and (5) the facies of the sciaphilic algae community. Thus, hard bottom communities in the Aegean seem to be separated mainly according to vertical zonation. A total of 68 hard-bottom species are under multiple exploitation, providing considerable economic profit. Taking into account the structural complexity of hard substrate benthic communities and their sensitivity to disturbances, it is essential to preserve the biodiversity of these biotopes

Clinical efficacy and safety of a light mask for prevention of dark adaptation in treating and preventing progression of early diabetic macular oedema at 24 months (CLEOPATRA): a multicentre, phase 3, randomised controlled trial

Background: We aimed to assess 24-month outcomes of wearing an organic light-emitting sleep mask as an intervention to treat and prevent progression of non-central diabetic macular oedema. Methods: CLEOPATRA was a phase 3, single-blind, parallel-group, randomised controlled trial undertaken at 15 ophthalmic centres in the UK. Adults with non-centre-involving diabetic macular oedema were randomly assigned (1:1) to wearing either a light mask during sleep (Noctura 400 Sleep Mask, PolyPhotonix Medical, Sedgefield, UK) or a sham (non-light) mask, for 24 months. Randomisation was by minimisation generated by a central web-based computer system. Outcome assessors were masked technicians and optometrists. The primary outcome was the change in maximum retinal thickness on optical coherence tomography (OCT) at 24 months, analysed using a linear mixed-effects model incorporating 4-monthly measurements and baseline adjustment. Analysis was done using the intention-to-treat principle in all randomised patients with OCT data. Safety was assessed in all patients. This trial is registered with Controlled-Trials.com, number ISRCTN85596558. Findings: Between April 10, 2014, and June 15, 2015, 308 patients were randomly assigned to wearing the light mask (n=155) or a sham mask (n=153). 277 patients (144 assigned the light mask and 133 the sham mask) contributed to the mixed-effects model over time, including 246 patients with OCT data at 24 months. The change in maximum retinal thickness at 24 months did not differ between treatment groups (mean change −9·2 μm [SE 2·5] for the light mask vs −12·9 μm [SE 2·9] for the sham mask; adjusted mean difference −0·65 μm, 95% CI −6·90 to 5·59; p=0·84). Median compliance with wearing the light mask at 24 months was 19·5% (IQR 1·9–51·6). No serious adverse events were related to either mask. The most frequent adverse events related to the assigned treatment were discomfort on the eyes (14 with the light mask vs seven with the sham mask), painful, sticky, or watery eyes (14 vs six), and sleep disturbance (seven vs one). Interpretation: The light mask as used in this study did not confer long-term therapeutic benefit on non-centre-involving diabetic macular oedema and the study does not support its use for this indication. Funding: The Efficacy and Mechanism Evaluation Programme, a Medical Research Council and National Institute for Health Research partnership

The Biodiversity of the Mediterranean Sea: Estimates, Patterns, and Threats

The Mediterranean Sea is a marine biodiversity hot spot. Here we combined an extensive literature analysis with expert opinions to update publicly available estimates of major taxa in this marine ecosystem and to revise and update several species lists. We also assessed overall spatial and temporal patterns of species diversity and identified major changes and threats. Our results listed approximately 17,000 marine species occurring in the Mediterranean Sea. However, our estimates of marine diversity are still incomplete as yet—undescribed species will be added in the future. Diversity for microbes is substantially underestimated, and the deep-sea areas and portions of the southern and eastern region are still poorly known. In addition, the invasion of alien species is a crucial factor that will continue to change the biodiversity of the Mediterranean, mainly in its eastern basin that can spread rapidly northwards and westwards due to the warming of the Mediterranean Sea. Spatial patterns showed a general decrease in biodiversity from northwestern to southeastern regions following a gradient of production, with some exceptions and caution due to gaps in our knowledge of the biota along the southern and eastern rims. Biodiversity was also generally higher in coastal areas and continental shelves, and decreases with depth. Temporal trends indicated that overexploitation and habitat loss have been the main human drivers of historical changes in biodiversity. At present, habitat loss and degradation, followed by fishing impacts, pollution, climate change, eutrophication, and the establishment of alien species are the most important threats and affect the greatest number of taxonomic groups. All these impacts are expected to grow in importance in the future, especially climate change and habitat degradation. The spatial identification of hot spots highlighted the ecological importance of most of the western Mediterranean shelves (and in particular, the Strait of Gibraltar and the adjacent Alboran Sea), western African coast, the Adriatic, and the Aegean Sea, which show high concentrations of endangered, threatened, or vulnerable species. The Levantine Basin, severely impacted by the invasion of species, is endangered as well

First assessment of Microcosmus sabatieri (Tunicata : Ascidiacea) small-scale artisanal fishery in the south Aegean sea (Eastern mediterranean)

The small-scale artisanal fishery of the edible turricate Microcosmus sabatieri was studied in the South Aegean Sea. Mean abundance was 156 +/- 53 ind.20' dive(-1) and the pattern of distribution was even. Size-frequency analysis indicated a mode around 10 cm at all surveyed islands; nevertheless, significant differences on mean size of the ascidians were observed, as average size decreased eastwards, probably related to increased demand

Net fisheries'métiers in the eastern Mediterranean: Insights for small-scale fishery management on Kalymnos Island

Small-scale fisheries constitute an important component of coastal human societies. The present study describes the small-scale net fisheries on Kalymnos Island (south-east Aegean Sea) that harbors the largest small-scale fleet in the eastern Mediterranean Sea. In addition, this study aims to evaluate their characteristics and economics. Relevant métiers were identified through a multivariate analysis by inputting the main resources and fishing gear data that were recorded during landings. Four main practices were observed being used as fishing gears, gillnets and trammel nets, targeting the species Mullus barbatus, Boops boops, Mullus surmuletus, Scorpaena porcus, and Sepia officinalis. Further analysis, which incorporated data concerning the type of the gear used, revealed 11 distinct métiers. Most of these métiers are practiced by other Mediterranean small-scale fisheries as well, in terms of target species, gear and seasonality. However, the métier that had its target species as B.boops is not practiced in other Mediterranean small-scale fisheries. The seasonal rotation of métiers was determined by the availability of different species rather than their market price. The results revealed the difference in fishing practice used by the fishermen in the study area compared to other fishing practices in the Mediterranean Sea. In particular, the fishermen of this study area targeted more species (B.boops) with a very low market price. They also provided essential information for the development and implementation of management plans aiming at the sustainability of small-scale fisheries. © 2019 by the authors

Marine invertebrate diversity in Aristotle's zoology

The aim of this paper is to bring to light Aristotle's knowledge of marine invertebrate diversity as this has been recorded in his works 25 centuries ago, and set it against current knowledge. The analysis of information derived from a thorough study of his zoological writings revealed 866 records related to animals currently classified as marine invertebrates. These records corresponded to 94 different animal names or descriptive phrases which were assigned to 85 current marine invertebrate taxa, mostly (58%) at the species level. A detailed, annotated catalogue of all marine anhaima (a = without, haima = blood) appearing in Aristotle's zoological works was constructed and several older confusions were clarified. Some of Aristotle's "genera" were found to be directly correlated to current invertebrate higher taxa. Almost the total of the marine anhaima were benthic invertebrates. The great philosopher had a remarkable, well-balanced scientific knowledge of the diversity of the various invertebrate groups, very similar to that acquired by modern marine biologists in the same area of study. The results of the present study should be considered as a necessary starting point for a further analysis of Aristotle's priceless contribution to the marine environment and its organisms

Small-scale fisheries in the south Aegean Sea: métiers and associated economics

Small-scale fishery is a major part of the society and the economy of the coastal and insular areas of the Mediterranean Sea. There has been an extensive interest in securing its sustainable exploitation and viability. This study presents the small-scale fishery of the Dodecanese Islands (Kalymnos, Kos, Leros, Patmos, Symi) where the largest small-scale fleet in the eastern Mediterranean is located. The aim is to evaluate the economic viability of small scale fishing fleets, based on calculating economic performance and by using linear regression models. The related métiers were identified by using a multivariate analysis and by inputting the main resources and fishing gear data that were collected during landings. The most important métiers concerning the fishing gear and the target species are: gillnet, Boops boops, trammel net, Scorpaena porcus and Mullus surmuletus, set longline, Pagellus erythrinus, Pagrus pagrus, Diplodus sargus, drifting longlines, Xiphias gladius and handlines, Octopus vulgaris. The economic analysis aims to present a methodology to measure the importance of small scale fishing fleets, on the basis of economic data and technical characteristics of the fleet. The length (m) of the vessel and the operation days were identified as the main factors affecting the gross revenue of the small-scale fishing fleet. Vital information for the development and implementation of management plans was provided by the results with the aim to sustain small-scale fisheries. © 2022 Elsevier Lt

Population structure and morphometric relationships of Paracentrotus lividus (Echinodermata: Echinoidea) in the South Aegean Sea

The gonads of the common sea urchin Paracentrotus lividus are a pricey gastronomic delicacy, and so the species is intensively harvested. Considering the recent collapse of its Populations in many Mediterranean areas and the lack of information for the Aegean Sea, a three-year survey was carried out focusing on population structure, morphometric relationships and reproductive status of P lividus in Astypalea, a South Aegean island, where the species is traditionally commercially exploited. Population density showed significant inter-annual variability, while its distribution pattern was contagious. P lividus individuals had larger size at the most sheltered site. Nevertheless, a significant interaction was detected among sites and years or seasons confounding the effect of these factors on the urchin's biometry. All the examined morphometric relationships followed negative allometry. The body diameter appeared to be a good predictor of its biomass. Voluminous gonads were present in several specimens of P lividus in all temporal samples; the gonad-somatic index peaked in early spring, particularly at the most sheltered site. Size-frequency distribution analysis revealed the presence of one mode of large sized individuals, implying that P lividus stocks have not been heavily fished yet in this area