Search Results (196)

Although marine caves are among the most species-diverse habitats in the Mediterranean Sea, most available studies have focused on their sessile fauna. This study provides the first quantitative assessment of motile fauna in 27 marine caves across four geographical subareas of the Aegean and Ionian Seas, using a rapid assessment visual census protocol, applied through 3 min time transects in each ecological cave zone. Multivariate analysis revealed that the motile community structure of the cave entrance was differentiated from that of the semidark and dark zones. Deeper caves were distinct from shallower ones while caves of the east Aegean differed from those around Crete Island. A total of 163 taxa were recorded, 27 of which are reported herein for the first time in marine caves of the eastern Mediterranean Sea, while three species (two native and one introduced) are recorded in Greek waters for the first time, enriching our knowledge on the permanent and occasional cave residents. Seventeen species were introduced, comprising more than half of the total fish abundance in the southeasternmost cave. Our limited knowledge of the motile fauna of Mediterranean marine caves coupled with the continued spread of introduced species highlights the urgent need for monitoring and conservation actions, especially within marine protected areas. Full article

The advanced determination of the type (foreshock–aftershock–swarm) of an ongoing seismic cluster is quite challenging; only retrospective solutions have thus far been proposed. In the period of January–March 2025, a seismic cluster, recorded between Santorini volcano and Amorgos Island, South Aegean Sea, caused considerable social concern. A rapid increase in both the seismicity rate and the earthquake magnitudes was noted until the mainshock of M_L = 5.3 on 10 February; afterwards, activity gradually diminished. Fault-plane solutions indicated SW-NE normal faulting. The epicenters moved with a mean velocity of ~0.72 km/day from SW to NE up to the mainshock area at a distance of ~25 km. Crucial questions publicly emerged during the cluster. Was it a foreshock–aftershock activity or a swarm of possibly volcanic origin? We performed real-time discrimination of the cluster type based on a daily re-evaluation of the space–time–magnitude changes and their significance relative to background seismicity using earthquake statistics and the topological metric betweenness centrality. Our findings were periodically documented during the ongoing cluster starting from the fourth cluster day (2 February 2025), at which point we determined that it was a foreshock and not a case of seismic swarm. The third day after the M_L = 5.3 mainshock, a typical aftershock decay was detected. The observed foreshock properties favored a cascade mechanism, likely facilitated by non-volcanic material softening and the likely subdiffusion processes in a dense fault network. This mechanism was possibly combined with an aseismic nucleation process if transient geodetic deformation was present. No significant aftershock expansion towards the NE was noted, possibly due to the presence of a geometrical fault barrier east of the Anydros Ridge. The 2025 activity offered an excellent opportunity to investigate deciphering the type of ongoing seismicity cluster for real-time discrimination between foreshocks, aftershocks, and swarms. Full article

Recent archaeological discoveries across the Aegean, Cyprus, and western Anatolia have renewed interest in pre-Neolithic seafaring and early island colonization. However, the environmental contexts that support such early coastal occupations remain poorly understood, largely due to the submergence of Pleistocene shorelines following post-glacial sea-level rise. This study addresses this gap through an integrated geoarchaeological investigation of the pre-Neolithic site of Ouriakos on Lemnos Island, northeastern Aegean (Greece), dated to the mid-11th millennium BCE. By reconstructing both the terrestrial and submerged paleolandscapes of the site, we examine ecological conditions, resource availability, and sedimentary processes that shaped human activity and site preservation. Employing a multiscale methodological approach—combining bathymetric survey, geomorphological mapping, soil micromorphology, geochemical analysis, and Optically Stimulated Luminescence (OSL) dating—we present a comprehensive framework for identifying and interpreting early coastal settlements. Stratigraphic evidence reveals phases of fluvial, aeolian, and colluvial deposition associated with an alternating coastline. The core findings reveal that Ouriakos was established during a phase of environmental stability marked by paleosol development, indicating sustained human presence. By bridging terrestrial and marine data, this research contributes significantly to the understanding of human coastal mobility during the Pleistocene–Holocene transition. Full article

Due to the potential role of Auchenorrhyncha in the transmission of the bacterium Xylella fastidiosa in a wide variety of cultivations, during recent years in Europe, many studies have focused on species composition, abundance and seasonal appearance of Auchenorrhyncha. However, females and nymphs are difficult to identify, as species-level identification relies primarily on male genitalia morphology. Sampling was conducted over four years in olive fields in Lesvos Island, in the Northeast Aegean, Greece, using sweep nets and Malaise traps. Both adults and nymphs were collected, with males identified to species level, while females and nymphs were separated on different morphotypes. Representatives from each morphotype and identified adults were sequenced using the mitochondrial cytochrome oxidase subunit I (COI) gene. Using a classical morphological approach, 58 species were identified to species level, and using DNA barcoding, nymph morphotypes and females were successfully identified within the families Cicadellidae, Aphrophoridae, Delphacidae and Issidae. A phylogenetic tree was generated, clustering nymphs together with the corresponding adults. Our results demonstrate the utility of combining morphological and molecular methods for accurate species identification and highlight the importance of enriching online databases with additional species records. Full article

Tinos Island, part of the Cyclades Complex in the central Aegean Sea, represents a distinctive case of geocultural heritage where geological formations and cultural identity intersect. This study evaluates the geoeducational and geotouristic potential of Tinos’ geosites using GEOAM methodology, which assesses their scientific, educational, and conservation value. Six geosites are examined to explore their geoeducational potential, including prominent locations such as the Tafoni formations and the Exombourgo granite massif. The findings highlight the significance of these sites, while also identifying challenges related to infrastructure, stakeholder engagement, and sustainable management. By integrating geoethics into geotourism practices, Tinos can adopt a balanced approach that enhances environmental conservation alongside community-driven economic benefits. The study underscores the need for collaborative initiatives to optimize the island’s geoheritage for education and tourism, ensuring its long-term preservation. Geotourism, when responsibly implemented, has the potential to strengthen local identity while advancing sustainable tourism development. Full article

Lethocerus patruelis (Stål, 1854) is a large aquatic hemipteran and the only European representative of the family Belostomatidae. Commonly known as the giant water bug, this species was historically restricted to the Balkans, Anatolia, and parts of the Middle East, but has exhibited a marked westward and northward range expansion in recent decades. In this study, we report the first confirmed occurrence of L. patruelis on Lesvos Island, in the northeastern Aegean Sea, based on a direct observation made within a wastewater treatment facility. The individual was identified in situ using diagnostic morphological traits and photographed without disturbance. This finding extends the known insular distribution of the species and underscores its capacity to exploit anthropogenically modified aquatic systems. Given the island’s rich mosaic of natural and artificial wetland habitats—including over 200 mapped sites—Lesvos may offer suitable conditions for the establishment of local populations. This record highlights the need for targeted surveys and long-term monitoring across under-sampled insular landscapes. Full article

In early 2025, the Santorini–Amorgos area (Aegean Volcanic Arc, Greece) experienced a seismic swarm, with dozens of M ≥ 4.0 earthquakes and a maximum magnitude of M = 5.2. Beyond its seismological interest, the sequence was notable for triggering rare increased preparedness actions by Greek Civil Protection operational structures in anticipation of an imminent destructive earthquake. These actions included (i) risk communication, (ii) the reinforcement of operational structures with additional personnel and equipment on the affected islands, (iii) updates to local emergency plans, (iv) the dissemination of self-protection guidance, (v) the activation of emergency alert systems, and (vi) volunteer mobilization, including first aid and mental health first aid courses. Although it was in line with contingency plans, public participation was limited. Volunteers helped bridge this gap, focusing on vulnerable groups. The implemented actions in Greece are also compared with increased preparedness during the 2024–2025 seismic swarms in Ethiopia, as well as preparedness before the highly anticipated major earthquake in Istanbul (Turkey). In Greece and Turkey, legal and technical frameworks enabled swift institutional responses. In contrast, Ethiopia highlighted the risks of limited preparedness and the need to embed disaster risk reduction in national development strategies. All cases affirm that preparedness, through infrastructure, planning, communication, and community engagement, is vital to reducing earthquake impacts. Full article

The Eastern Aegean Sea hosts a diverse assemblage of elasmobranchs, many of which are vulnerable or endangered. This study presents a fishery-independent assessment of species composition, catch characteristics, and spatial patterns in bottom trawl fisheries between Lesvos Island and Ayvalik. A total of 48 surveys were conducted between September 2022 and October 2024, identifying nine elasmobranch species, with Scyliorhinus canicula (small-spotted catshark) and Mustelus mustelus (common smooth-hound) dominating the catch. Biological parameters, sex ratios, and condition upon capture and release were recorded, while catch per unit effort (CPUE) and diversity indices were used to evaluate temporal patterns. The survival probability was negatively affected by the trawl duration and elevated temperatures, emphasizing the need for mitigation measures. Spatial models revealed high-density zones that likely function as foraging or nursery grounds. Seasonal shifts in community composition were also evident. Many non-commercial species were discarded irrespective of their size or condition. These findings underscore the ecological importance of this understudied region and support the need for spatially explicit, species-specific management strategies, including gear selectivity improvements, seasonal closures, and Electronic Monitoring. The study offers a critical baseline for enhancing the sustainability of elasmobranch populations in the Eastern Mediterranean. Full article

Serpentinite is a common lithology in Greece with significant geotectonic and petrogenetic implications, yet its archaeometric study remains limited. This also applies to the Ras serpentinite outcrop on Tinos Island—an enigmatic ancient quarry with no prior documentation of its exploitation. This study aims to provide a holistic provenance analysis and full material characterization to establish a unique fingerprint for future comparative research. A multidisciplinary methodology was applied, including petrography, XRD, FTIR, BET, LA-ICP-MS, electron microprobe analyses, and lichenometry—the latter used to estimate the quarry’s period of activity. The Ras serpentinite consists of a dark-green, brecciated lizardite matrix cut by a pale-green chrysotile network, and notably hosts the first recorded occurrence of minnesotaite in Greece. Relict antigorite within the matrix indicates high-pressure, high-temperature metamorphism preceding a greenschist facies overprint. Geochemical data classify the Ras occurrence as a subduction-related serpentinite derived from a depleted ultrabasic protolith. The aforementioned traits distinguish it from other Greek examples. Lichenometric analysis suggests the quarry was active in the 13th century A.D., with evidence of deliberate extraction techniques. These findings offer valuable insights into archaeometric studies and the provenance of serpentinites in the Aegean. Full article

Argonauta argo (Linnaeus, 1758), commonly known as the greater argonaut, is a pelagic octopod with a circumglobal distribution in warm and temperate seas. Although the species is occasionally reported in the Mediterranean Sea, confirmed in situ observations of live individuals remain scarce, particularly in the eastern basin. Here, we document the occurrence of a live female A. argo entangled in aquaculture nets at a sea bass (Dicentrarchus labrax) facility off the coast of Lesvos Island in the northeastern Aegean Sea, Greece. This represents the first confirmed observation in this part of the Mediterranean and only the second confirmed observation of a live individual in Greek waters. The individual was photographed in situ and identified based on diagnostic morphological features. The encounter occurred under specific hydrodynamic and environmental conditions potentially favorable to the species, including enhanced prey availability and structural refuge within the aquaculture infrastructure. This record contributes to the limited dataset on Mediterranean argonauts and underscores the need for further research into their ecology, distribution patterns, and potential interactions with anthropogenic marine structures. Full article

The objective of this study is to compare the most common methods for forecasting wave characteristics (height and period) for the maximum in height 1/3, 1/10, and 1/100 of the waves, using available wind and wave datasets. The testing marine region is the Central Aegean Sea and, in particular, the east coast of Evia Island that is exposed to N, NE, E, and SE incoming offshore waves. The estimated values of wave characteristics resulting from three different wind datasets and the two wave datasets present differences of 2–60%. These variations are attributed to the different methodological approaches followed, to the different types of raw data in terms of space and time periods, and to the fetch limitations. The proposed methodology for the calculation of wave characteristics for the highest (1/10) and (1/100) waves appears to yield reasonable outcomes when compared to the corresponding significant (highest 1/3) wave heights and periods. Finally, mean values of wave height and period calculated from the five available datasets, considering their standard deviation, seem to be more representative than the values calculated separately from each dataset. Full article

Unraveling the evolutionary history of Brassica L. crops and their wild relatives remains a key challenge in plant evolutionary biology. Brassica cretica is considered the closest living relative of the cultivated B. oleracea. It is mainly distributed in the Aegean Islands and the neighboring mainland regions of Greece and Anatolia, and exhibits extensive phenotypic variability, obscuring its infraspecific classification. In this study, we analyzed five Greek populations of B. cretica and one B. oleracea botanical variety using SSR markers to assess genetic diversity and differentiation. High genetic diversity was detected within natural populations, with a mean of 21.9 alleles per locus and an expected heterozygosity of 0.647. Significant genetic differentiation (Fst = 0.812) revealed the presence of four distinct gene pools, partly supporting the current infraspecific classification of B. cretica. The cultivated plants cluster closely with B. cretica subsp. cretica, supporting the hypothesis of an Eastern Mediterranean origin. Our findings suggest that B. cretica subsp. cretica may have been introduced to suitable habitats or that cultivated plants may have reverted to a feral state in the Peloponnese, given the genetic similarity between populations from Crete and northern Peloponnese. The identified genetic diversity underscores the importance of B. cretica as a genetic resource for breeding programs and highlights the need for conservation, particularly for populations exhibited unique genetic traits. Full article

The diversification of lineages sometimes exhibits patterns that are often described as ‘radiations’, which can be seen at various time scales, but researchers most often focus on a fast divergence of parental forms within short time spans. Adaptive radiations are widely discussed and have served as important showcases of Darwinian evolutionary processes. Other types of radiation have been identified, too, and several classifications have been suggested. Among these, ‘non-adaptive radiations’ remain controversial till today. Despite concerns on the conceptual basis of such a process, more and more cases of radiation that are described as ‘non-adaptive’ are published, and the continuously accumulating genetic/genomic data for more and more taxa seem to reveal extensive lineage diversification that is often not attributable to any apparent selective force. Given that allopatric divergence due to stochastic processes is presumably the cause of non-adaptive radiations, insular systems provide a rich pool of case studies. Using examples of lineage divergence from various taxa living on the Aegean islands, I discuss the processes leading to non-adaptive radiations in view of the alternative classifications of radiation by other authors, and show that such patterns may also result from a mixture of adaptive and non-adaptive processes. Full article

Anthropogenic climate and land use change pose major threats to island floras worldwide, yet few studies have integrated these drivers in a single vulnerability assessment. Here, we examine the endemic flora of Evvia, the second-largest Aegean island in Greece and an important biodiversity hotspot, as a model system to address how these disturbances may reshape species distributions, community composition, and phylogenetic diversity patterns. We used species distribution models under the Ensemble of Small Models and the ENphylo framework, specifically designed to overcome parameter uncertainty in rare species with inherently limited occurrence records. By integrating climate projections and dynamic land use data, we forecasted potential range shifts, habitat fragmentation, and biodiversity patterns for 114 endemic taxa through the year 2100. We addressed transferability uncertainty, a key challenge in projecting distributions under novel conditions, using the Shape framework extrapolation analysis, thus ensuring robust model projections. Our findings reveal pronounced projected range contractions and increased habitat fragmentation for all studied taxa, with more severe impacts on single-island endemics. Our models demonstrated high concordance with established IUCN Red List assessments, validating their ecological relevance despite the sample size limitations of single-island endemics. Current biodiversity hotspots, primarily located in mountainous regions, are expected to shift towards lowland areas, probably becoming extinction hotspots due to projected species losses, especially for Evvia’s single-island endemics. Emerging hotspot analysis identified new biodiversity centres in lowland zones, while high-altitude areas showed sporadic hotspot patterns. Temporal beta diversity analysis indicated higher species turnover of distantly related taxa at higher elevations, with closely related species clustering at lower altitudes. This pattern suggests a homogenisation of plant communities in lowland areas. The assessment of protected area effectiveness revealed that while 94.6% of current biodiversity hotspots are within protected zones, this coverage is projected to decline by 2100. Our analysis identified conservation gaps, highlighting areas requiring urgent protection to preserve future biodiversity. Our study reveals valuable information regarding the vulnerability of island endemic floras to global change, offering a framework applicable to other insular systems. Our findings demonstrate that adaptive conservation strategies should account for projected biodiversity shifts and serve as a warning for other insular biodiversity hotspots, urging immediate actions to maintain the unique evolutionary heritage of islands. Full article

Climate conditions in combination with the concentration of pollutants increase the human health stress and exacerbate systemic diseases. The city of Rhodes is a desirable tourist destination that is located in a sensitive climate region of the southeastern Aegean Sea in the Mediterranean region. In this work, hourly recordings from a mobile air quality monitoring system, which is located in an urban area of Rhodes city, are employed in order to measure the concentration of regulated pollutants (${\mathrm{S}\mathrm{O}}_2,{\mathrm{N}\mathrm{O}}_2,{\mathrm{O}}_3,{\mathrm{P}\mathrm{M}}_{10} \mathrm{a}\mathrm{n}\mathrm{d} {\mathrm{P}\mathrm{M}}_{2.5})$ and meteorological factors (pressure, temperature, and relative humidity). The air quality health index (AQHI) and the discomfort index (DI) are calculated to study the impact of air quality and meteorological conditions on human health. The analysis is conducted during a hot summer period, from 29 June to 14 July 2024. During the second half of the studied period, a heatwave episode occurred that affected the bioclimatic conditions over the city. The results show that despite the fact that the concentration of pollutants is lower than the pollutant thresholds (according to Directive 2008/50/EC), the AQHI and DI conditions degrade significantly over the heatwave days. In particular, the AQHI is classified in the “Moderate” class, and the DI indicates that most of the population suffers discomfort. The AQHI and DI simultaneously increase during the days of the heat episode, showing a possible negative synergy for the health risk. Finally, both the day maximum and night minimum temperature are increased (about 0.8 and 0.6 °C, respectively) during the heatwave days as compared to the whole studied period. Full article