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Data with high spatial resolution on the structure and diversity of marine assemblages are valuable for fisheries management and conservation planning but are seldom available. This study provides fisheries-independent, baseline information on the structure and diversity of the demersal fish assemblages of the continental shelf and upper slope off the island of Psara (Central Aegean Sea). Experimental bottom trawl hauls were conducted during 2009–2010, using identically designed trawls. All the fish in the catches were identified onboard, enumerated, and weighted to the nearest g. Species abundance and biomass were transformed to CPUE. Forty-seven taxa were identified in the catches. For 18 of the species caught no other fisheries-independent information on their abundances and distributions is available for the wider area. Among the Elasmobranchii species collected, Squalus acanthias, Dipturus oxyrinchus, and Raja clavata are species of conservation concern. Species composition was generally more similar to that reported for assemblages of the Cretan Sea and the South Aegean Sea than for assemblages of the North Aegean. The assemblages were structured with depth, a pattern that may be driven in part by the differences in benthic habitat between depth zones. No trends by depth in total numerical abundance and species diversity were identified, whereas the bathymetric change in taxonomic diversity was attributed to the depth distributions of certain species-rich orders and families. The frequency distribution of the trophic level of the species followed the broad-scale pattern that applies in the Mediterranean Sea.

Research known as Citizen Science (CS) has been recognized as an important tool for both biodiversity restoration and fisheries management projects through active involvement of citizens and therefore for public environmental awareness too. CS projects should be well designed and state clear questions, that will benefit both the research goals and the citizen scientists themselves. In January 2019, the “Red Fish Project” group was created on Facebook consisting of SCUBA divers and fishers and offering the main data source and the relevant digital material. The project’s establishment was based on previous personal experience and following specific protocols. Further information was provided by personal communications. Till October 21st, 2020 the FB group consisted of 464 members who recorded 348 European spiny lobster individuals from all sub-regions of the Aegean Sea. Based on the findings of the present study it seems that most of the citizens were unaware that the species is listed as “Vulnerable” in the IUCN Red List. Lastly, we discuss the important role of the spiny lobster in the country’s culture and that it can be listed as a charismatic, flagship species for citizens to be ocean-literate since it has been shown, that it can raise the interest of recreational divers and increase their awareness.

This study investigates the trophic diversity of fishes living in a meadow of Caulerpa prolifera on a bimonthly basis between May 2006 and April 2007 in a semi-enclosed coastal marine ecosystem of the Mediterranean Sea (Elounda Bay, Crete Island). The study area is shallow and protected from waves, and it is covered by a C. prolifera bed, characterized by high organic input and a highly diverse macrobenthic community. Feeding patterns of the fish, investigated on the basis of stomach content analyses, were described in terms of numerical abundance and frequency of occurrence of prey taxa. A total of 1642 fish individuals, belonging to 17 species, were examined. In total, 45,674 prey individuals were identified belonging to 110 prey taxa, most of which were Malacostraca including their larvae and Copepoda (41,175 individuals identified to 71 taxa). Four different trophic groups were identified: herbivorous, pelagic, benthic (hyperbenthic) and piscivorous. Trophic diversity patterns of the fish species studied were also compared to the relative availability of macrobenthic and zooplanktonic taxa during the same period in the study area. The coexistence of many different, mostly benthic but also pelagic, fishes and their juveniles implies their high trophic flexibility, which is probably important for their survival in this particular habitat. Results of the present study provide basic knowledge on trophic diversity and interactions in the marine ecosystem and, therefore, some evidence as to the protection value of this particular habitat, which is essential for the implementation of a multispecies approach to decision-makers and managers of fisheries sources of the region.

The European spiny lobster Palinurus elephas is a vulnerable species that inhabits and is harvested in the Mediterranean Sea and the adjacent Atlantic waters. The fisheries associated with the spiny lobster are mainly conducted with tangle nets, trammel nets, pots, and creels. The fishing pressure has greatly reduced their numbers, changing them from a common shallow coastal species to a largely remnant population. The relative research on the species&rsquo, biology and fisheries from the eastern Mediterranean Sea is almost absent. The fishery along the Chalkidiki Peninsula, Greece, is multispecies, and fishing is conducted by a small number of artisanal fishermen mainly using trammel nets. The lobster stock&mdash, both spiny and clawed lobsters&mdash, declined significantly during the late 1980s and early 1990s, later than most cases in the Mediterranean Sea. However, data regarding the nature and status of the fishery associated with the spiny lobster in Greece are lacking. Data regarding the characteristics of the spiny regional fishery were obtained by interviews and questionnaires. Additionally, fishery surveys were conducted during the main lobster fishing season from 1 May 2017 to 31 August 2017. Sixteen species were identified (15 finfish species and one invertebrate species) as targeted. In total, 79 spiny lobsters were sampled in this study, the population&rsquo, s sex ratio significantly diverts from the theoretical 1:1 (&chi, 2 = 4.57, p &lt, 0.05), and males were dominant. Both male and female individuals demonstrate negative allometric growth profiles. In addition, no significant differences were observed between sexes. In Greece, thus far, the knowledge and information are sporadic, limited, and/or species-specific, most of which regard finfish fisheries. Furthermore, the national legislation is rather complicated&mdash, or too generalized&mdash, thus creating great uncertainties. The in-depth knowledge and experience of fishermen should be further acknowledged and utilized, and wider collaborations among scientists, practitioners, and policy-makers should be established. The present study poses some thoughts on the effectiveness of the recent EU Landing Obligation and its contribution to the potential restoration of the species.

The spread of artificial night lighting is increasingly acknowledged as a major threat to global biodiversity. Identifying and exploring the impacts of nightlight pollution upon species behavior, ecology and population dynamics could enhance conservation capacity. Sea turtle hatchlings emerge from nest at night and use visual cues to direct towards the brightest and lowest horizon, eventually leading them to the sea. Nightlight pollution could alter the cues perceived, disorienting the fragile hatchlings. We examined the level of artificial lighting and orientation patterns of sea turtles hatchling, in Zakynthos Island, Greece, one of the main nesting rookeries of the loggerheads ( Caretta caretta ) in the Mediterranean Sea. We analyzed movement patterns of 5967 hatchlings from 230 nests, and demonstrate that nightlight pollution could reduce population recruitment by more than 7%, suggesting that mitigation measures should become a high conservation priority. Our results further suggest that the responses of sea turtle hatchlings to artificial nighttime lighting could vary significantly depending on various factors, either anthropogenic or natural. Local conditions operating at the nesting site level determine the fine scale responses of hatchlings, thus conservation measures should be drawn in respect to site-specific properties.

The present study investigates the structure and intra-annual variation of the benthic macrofaunal community associated with a monospecific C. prolifera meadow in a shallow semi-enclosed coastal marine ecosystem of the eastern Mediterranean Sea (Elounda Bay, Crete Island). The samples were collected on five occasions (May, September and November 2006, February and April 2007) by using an epibenthic sledge (0.5 mm mesh size). The analysis of the macrofauna revealed 319 taxa with densities ranging from 71 to 410 individuals m −2 . The most diversified animal groups were polychaetes, gastropods and amphipods. Crustaceans were by far the most abundant group with densities exceeding 50% of the total macrofauna during the study period. The dominant species were the amphipods Caprella acanthifera acanthifera, C. rapax and Microdeutopus stationis, the gastropod Pusillina lineolata, the tanaid Leptochelia sp. and the bivalve Abra alba. The results of the present study revealed a relatively high diversified and abundant benthic macrofauna, which is supported by the presence of the dense and continuous canopy of C. prolifera in this shallow wave-sheltered area characterized by high organic matter input.

15 pages, 6 figures, 4 tables, Coralligenous formations are biogenic structures typical of the underwater Mediterranean seascape. Their intricate, multi-layered species assemblages are composed of perennial, long-lived organisms, particularly vulnerable to natural or human-induced disturbances. Despite their high ecological role and conservation value, few studies have addressed the assemblages outside the NW Mediterranean. This is the first quantitative assessment of coralligenous in the N Aegean Sea (NE Mediterranean), specifically focusing at the upper bathymetric limit of assemblages that are dominated by the yellow gorgonian Eunicella cavolini. The number and percent cover of macrobenthic species were studied at depths of 18 to 35 m, using a photoquadrat method. A total of 99 benthic taxa were identified, out of which 89 perennial ones were used to investigate spatial patterns in assemblage structure, composition, and biodiversity. A mean number of 47 perennial taxa were recorded per site, with encrusting coralline algae and sponges being the dominant groups in percent cover and species number, respectively. Across the studied localities, structural complexity and community composition were overall similar, but assemblages presented distinctive differences at the level of sites highlighting the role of local abiotic and anthropogenic factors in the shaping of the coralligenous. Compared to the rest of the Mediterranean, assemblages hosted a similar number of taxa. However, the number and percent cover of erect bryozoans were generally low, while, apart from E. cavolini, other erect anthozoan species were absent. This work provides an important baseline for comparisons and monitoring at a local or Mediterranean scale level, This work has been co-financed by the EU Social Fund and Greek National Funds through the NSRF 2007-2013 Research Funding Program: Heracleitus II, Investing in knowledge society

Understanding the interactions among invasive species, native species and marine protected areas (MPAs), and the long-term regime shifts in MPAs is receiving increased attention, since biological invasions can alter the structure and functioning of the protected ecosystems and challenge conservation efforts. Here we found evidence of marked modifications in the rocky reef associated biota in a Mediterranean MPA from 2009 to 2019 through visual census surveys, due to the presence of invasive species altering the structure of the ecosystem and triggering complex cascading effects on the long term. Low levels of the populations of native high-level predators were accompanied by the population increase and high performance of both native and invasive fish herbivores. Subsequently the overgrazing and habitat degradation resulted in cascading effects towards the diminishing of the native and invasive invertebrate grazers and omnivorous benthic species. Our study represents a good showcase of how invasive species can coexist or exclude native biota and at the same time regulate or out-compete other established invaders and native species.

The present study investigated for the first time in the eastern Mediterranean Sea species composition, density, wet biomass and body size of fish and cephalopod species associated with a Caulerpa prolifera meadow in a shallow semi-enclosed coastal marine ecosystem (Elounda Bay, Crete Island). Quantitative sampling with a local boat seine, revealed 34 fish species belonging to 22 families and three cephalopod taxa. The number and density of species peaked during the summer sampling period due to high numbers of juveniles, while the highest wet biomass was observed during the autumn sampling period. The fish species Boops boops , Spicara smaris , Mullus barbatus and the non-indigenous Siganus luridus were dominant, making up a high proportion of the total fish fauna of the studied area. The cephalopod Sepia officinalis was the most important species, in terms of wet biomass. The results of the study indicated that the semi-enclosed coastal marine ecosystem of Elounda Bay, characterized by a dense monospecific C. prolifera bed as well as specific abiotic and biotic features could be regarded as an important habitat for the development of fish and cephalopod species, thus contributing to the conservation and maintenance of marine biological resources of the area.

In the Mediterranean Sea, infralittoral and circalittoral rocky bottoms (from 15 to 120 m) are characterized by a biogenic habitat, named “coralligenous”, formed by the concretion of calcareous organisms, mainly algal thalli, and to a lesser extent by animal skeletons. This complex habitat is inhabited by a rich fauna that belongs to different taxonomic groups. Sponges, bryozoans, cnidarians and ascidians are the most common sessile organisms that inhabit the area, while crustacea and molluscs are the most common mobile organisms. Little information on the diversity of the molluscs that thrive in the coralligenous habitat is known, though this information is highly important for biodiversity management purposes. A database for the molluscs of the coralligenous habitat was compiled and a method implemented for the management of this information. More than 511 species of molluscs have been recorded so far from the coralligenous formations, the majority of which belong to the class Gastropoda (357 sp.) followed by Bivalvia (137 sp.), Polyplacophora (14 sp.), Cephalopoda (2 sp.) and Scaphopoda (1 sp.). Among these, the gastropod Luria lurida (Linnaeus, 1758) and Charonia lampas (Linnaeus, 1758), the endemic bivalve Pinna nobilis (Linnaeus, 1758) and the endolithic bivalve Lithophaga lithophaga (Linnaeus, 1758), are protected by international conventions.

Environmental change can alter both species distribution range patterns at a regional scale and their feeding habits at a local scale. While several studies have highlighted the mechanisms driving such changes separately, little is known on their combined effect on the local communities. In this manuscript, we used both feeding and distributional traits of macro-benthic species and examined their combined response across an environmental gradient induced by an aquaculture unit. Our results mainly suggest that specialized predators with narrow geographic distributions and niches were more sensitive to environmental change than the less specialized groups. Moreover, under harsh environmental conditions, predatory species with a wide dispersion capacity can sustain viable populations through niche generalization. In contrast, in areas of low environmental disturbance, predatory species with a more restricted dispersal capability (i.e. some endemic species) can coexist via niche differentiation. In this context, our findings contribute towards a better understanding of benthic communities’ functional response to environmental change and may be of use in environmental impact assessment.

The benthic boundary layer (BBL) macrofauna consists of epibenthic, hyperbenthic and zooplanktonic organisms with different degrees of mobility and bottom dependence. The top-level predators within this habitat include demersal fish species. The BBL species are considered to be the most readily available prey for these fish making them an attractive source of food and therefore key taxa in marine food webs. The present study is a field experiment in the oligotrophic continental shelf of Heraklion Bay (Cretan Sea, eastern Mediterranean) investigating the ways in which demersal fish utilize BBL sources as food. Species diversity patterns derived from samples collected by using a modified hyperbenthic sledge as well as different benthic, hyperbenthic and pelagic samplers are described. These patterns are compared with those derived from stomach content analysis of demersal fish species inhabiting the same area. Results reveal that BBL macrofaunal communities which comprise most of the available prey communities are largely exploited by demersal fish species. Furthermore, the application of different samplers provides complementary information on prey selectivity of macrofaunal organisms by demersal fish species, highlighting further the trophic interactions within the BBL habitat.

The effective conservation of marine biodiversity through an integrated ecosystem-based management approach requires a sound knowledge of the spatial distribution of habitats and species. Although costly in terms of time and resources, acquiring such information is essential for the development of rigorous management plans and the meaningful prioritization of conservation actions. Located in the northeastern part of the Mediterranean, the Aegean Sea represents a stronghold for marine biodiversity. However, conservation efforts are hampered by the apparent lack of spatial information regarding marine habitats and species. This work is the first to address this knowledge gap by assembling, updating, and mapping information on the distribution of key ecological components. A range of data sources and methodological approaches was utilized to compile and complement the available data on 68 ecological features of conservation interest (58 animal species, six habitat categories, and four other vulnerable ecological features). A standardized data evaluation procedure was applied, based on five semi-quantitative data quality indicators in the form of a pedigree matrix. This approach assessed the sufficiency of the datasets and allowed the identification of the main sources of uncertainty, highlighting aspects that require further investigation. The overall dataset was found to be sufficient in terms of reliability and spatiotemporal relevance. However, it lacked in completeness, showing that there are still large areas of the Aegean that remain understudied, while further research is needed to elucidate the distribution patterns and conservation status of several ecological features; especially the less charismatic ones and those found in waters deeper than 40 m. Moreover, existing conservation measures appear to be inadequate to safeguard biodiversity. Only 2.3% of the study area corresponds to designated areas for conservation, while 41 of the ecological features are underrepresented in these areas. Considering the high geomorphological complexity and transnational character of the Aegean Sea, this study does not offer a complete account of the multifaceted diversity of this ecoregion. Instead, it represents a significant starting point and a solid basis for the development of systematic conservation plans that will allow the effective protection of biodiversity within an adaptive management framework.

Marine Protected Areas (MPAs) now form an important part of marine conservation and fisheries management; hence, there is broad interest in developing procedures that optimize their design. We used data collected over a 10-year period (2003–2012) from direct surveys and >100 adult male and female loggerhead sea turtles (Caretta caretta) tracked with devices, including GPS loggers and Fastloc GPS-Argos, to consider the optimum design for a MPA at a globally important breeding area, where there is already an existing national marine park aiming to protect the population (Zakynthos, Greece). Turtles primarily used areas very close to shore (approx. 7 km in length by 1 km in width, within the

This paper describes two datasets on the molluscan fauna from the Mediterranean infralittoral reef ecosystem - the biocoenosis of photophilic algae. The first dataset is taken from the East Mediterranean node of the NAGISA project. The second one is a compilation based on the available published material in peer - reviewed journals as well as from the accessible grey literature. These datasets cover a time period of 43 years from 1969 to 2012 from several locations spanning the Mediterranean Sea. This dataset is the only one available from this important Mediterranean Habitat, coded as 1170 in the Habitats Directive (92/43/EEC) and can provide valuable information on the needs of ecosystems functions and services assessment, habitat and species conservation as well as marine spatial planning.

Giakoumi, Sylvaine ... et al.-- 12 pages, 4 figures, 1 table, supporting information https://dx.doi.org/10.1111/ddi.12491.-- Data accessibility: Critical habitats GIS layers (distribution of seagrass meadows Posidonia oceanica and coralligenous formations) used in this article are available on MedOBIS database: http://lifewww-00.her.hcmr.gr:8080/medobis/resource.do?r=posidonia, http://life www-00.her.hcmr.gr:8080/medobis/resource.do?r=coralligenous. Endemic fish GIS layers are available on Ecological Archives: http://www.esapubs.org/archive/ecol/E096/203/#data, Aim: Biological invasions are major contributors to global change and native biodiversity decline. However, they are overlooked in marine conservation plans. Here, we examine for the first time the extent to which marine conservation planning research has addressed (or ignored) biological invasions. Furthermore, we explore the change of spatial priorities in conservation plans when different approaches are used to incorporate the presence and impacts of invasive species. Location: Global analysis with a focus on the Mediterranean Sea region. Methods: We conducted a systematic literature review consisting of three steps: (1) article selection using a search engine, (2) abstract screening and (3) review of pertinent articles, which were identified in the second step. The information extracted included the scale and geographical location of each case study as well as the approach followed regarding invasive species. We also applied the software Marxan to produce and compare conservation plans for the Mediterranean Sea that either protect, or avoid areas impacted by invasives, or ignore the issue. One case study focused on the protection of critical habitats, and the other on endemic fish species. Results: We found that of 119 papers on marine spatial plans in specific biogeographic regions, only three (2.5%) explicitly took into account invasive species. When comparing the different conservation plans for each case study, we found that the majority of selected sites for protection (ca. 80%) changed in the critical habitat case study, while this proportion was lower but substantial (27%) in the endemic fish species case study. Main conclusions: Biological invasions are being widely disregarded when planning for conservation in the marine environment across local to global scales. More explicit consideration of biological invasions can significantly alter spatial conservation priorities. Future conservation plans should explicitly account for biological invasions to optimize the selection of marine protected areas, G. was supported by ARC CEED (University of Queensland) funding and the ANR project PAVIS; S. Kark by the Australian Research Council; J.C. by ERa-Net BiodivERsA (BUFFER project); R.D. by the programme DEVOTES (7FP); S.F. by the EU Project COCONET (7FP, Grant Agreement No. 287844); M.C. by a Marie Curie Career Integration Grant Fellowship (PCIG10-GA-2011-303534); and J.B.L by a post-doctoral grant (SFRH/BPD/74400/2010) from the Portuguese Foundation for Science and Technology. F.M. acknowledges the support of the Pew Charitable Trust

The present study aims to detect functional diversity as well as functional redundancy patterns of soft bottom benthic communities in relation to the prevailing environmental factors, across several brackish water areas. We further tested whether differences in spatial scale can account for the possible variability in functional trait distribution, as well as for the local community assembly processes driven by species functional traits. Our main results suggested that environmental variation induces a large amount of variability in functional trait distribution at local and regional scale, a result which underscores the importance of habitat and environmental variation in the functioning of soft sediments in brackish areas. Conversely to functional diversity, functional redundancy remained invariable in both local and regional scales, therefore acting as an insurance against the enhanced environmental variability and maintaining ecosystem processes and services. Our findings led us also to conclude that environmental factors control the distribution of certain functional traits thus acting as environmental filters, in both local and regional scales. On the other hand, dominant species interactions accounted for the reduced levels of functional divergence at the less confined brackish water areas. This finding supported the view that interactions among dominant species can potentially induce negative effects on the functionality of brackish water soft sediments. From all the above, it is reasonable to assume that community shaping and functioning of the examined brackish water areas are governed by both biotic interactions and environmental filters, which are acting simultaneously at varying degrees of influence.

The relation of macrobenthic species turnover (beta diversity) and species plylogenetic variation with functional diversity patterns, across an environmental gradient induced by an aquaculture unit, in a coastal area of the island of Lesvos (NE Aegean) has been investigated in this study. The contribution of rare species response and species dispersal ability in the variation of functional diversity patterns along the environmental gradient, on a spatio-temporal scale, has been also examined. Our results revealed that benthic functional diversity was decreasing monotonically with increasing species turnover rate and hence with increasing spatial variability along the environmental gradient. Increased environmental stress which was detected in the immediate vicinity of the fish cages resulted to low species functional redundancy, since different species didn’t perform the same functional role at the most disturbed part of the established gradient. Functional diversity patterns were found to be correlated with species population size, whereas a strong linear relationship was also detected with phylogenetic diversity patterns, thus supporting the claim that wider local taxonomic trees can support a wider range of species functions even in small spatial scales. Rare species loss seemed to be one of the dominant factors ruling functional diversity variation. Species with the minimum possible dispersal ability, which were mostly rare, tend to diminish both in species number and population size faster than species with wider dispersal ability towards the most disturbed areas. The aforementioned results indicate that rare species variation and endemic species loss are critical factors in determining functional diversity loss across a human-induced environmental gradient in soft bottom benthic communities.

Solar saltworks are extremely heterogeneous coastal aquatic ecosystems whose benthic biodiversity patterns have not been comprehensively investigated yet. The present study focuses on the seasonal community structure of the macrobenthic molluscs at the marine‐lagoonal environmental transition that takes place at Kalloni solar saltworks (Lesvos Island, NE Aegean Sea, Greece). The molluscan community was studied by means of four seasonal collections carried out in 2004 at four sites in the study area. The molluscan community was found to be considerably species‐rich and forming a coenocline, as marine species were gradually replaced by lagoonal species with increasing distance from the sea. The major variable in the implied environmental gradient structuring the molluscan community appeared to be confinement rather than salinity, although zonation of the molluscan community structure was rather broad. The pattern of spatial organization of the molluscan fauna did not appear to change seasonally, although se...

The distribution patterns of fish assemblages within streams can provide insights for river type classifications and may warrant specific conservation actions. However, there is limited knowledge of how fish assemblages assort along a longitudinal axis in Mediterranean intermittent streams. Patterns in spatial and temporal distribution of fish communities were analysed in a Mediterranean intermittent river (Evrotas River) located in Southern Greece, hosting three endemic range restricted species of high conservation concern, during the period 2007−2009, with 80% of the river’s total length desiccating in the 2007 and 2008 droughts. The general trend was an increase in fish density and species richness along an upstream-downstream gradient. Fish assemblages from upstream to downstream were characterized by a decrease of the most rheophilic species (Squalius keadicus) and an increase of the most stagnophilic species (Tropidophoxinellus spartiaticus). Three river segments, characterized by a high degree of homogeneity were delineated. Habitat and environmental preferences for the studied fish species were identified, with elevation and low flowing habitats being the most important environmental factors affecting fish distribution patterns. The current study provides evidence that even in an intermittent river an assemblage pattern following a longitudinal gradient can be identified, mainly due to the lack of instream barriers that allows recolonization after flow resumption.

19 pages, 7 figures, 6 tables, supporting information http://dx.doi.org/10.1371/journal.pone.0126253, The yellow octocoral Eunicella cavolini is one of the most common gorgonians thriving in Mediterranean hard-bottom communities. However, information regarding its distribution and ecology in several parts of the Mediterranean is lacking, while population trends and conservation status remain largely unknown. We investigated 19 populations of E. cavolini over three representative geographic regions: the NW Mediterranean, CE Adriatic, and N Aegean. Focusing on the upper bathymetric range of the species (30 cm). The CE Adriatic displayed intermediate densities, with well-structured populations, and continuous recruitment. In the N Aegean, most populations presented low densities, high proportion of large colonies, but low number of small colonies, signifying limited recruitment. Disturbance levels, as a function of extent and type of injury, are discussed in relation to past or present human-induced threats. This work represents geographically the most wide ranging demographic study of a Mediterranean octocoral to date. The quantitative information obtained provides a basis for future monitoring at a Mediterranean scale. © 2015 Sini et al., MS research activity has been co-financed by the European Union (European Social Fund – ESF) and Greek national funds (Ministry of Education and Religious Affairs managing authority) through the Operational Program >Education and Lifelong Learning> of the National Strategic Reference Framework (NSRF) - Research Funding Program: Heracleitus II. Investing in knowledge society through the European Social Fund. SK received funding provided by the Croatian Ministry of Culture through the grant allocated to Marine Explorers Society –“20,000 leagues” in 2009 and by the Croatian Ministry of Science and Education (project 119-0362975-1226)

Cross-community congruence patterns of species diversity metrics and community sim- ilarity between macrobenthic infauna, epibenthic megafauna, demersal fish and microzooplankton ciliates were studied in 6 areas in the Eastern Mediterranean. These species-rich communities, co- occurring in space and time, were intensively sampled during 2 cruises, in seasons reflecting differ- ent levels of subtle anthropogenic stress. Comparisons of patterns showed high positive correlation of similarities in community structure between macrofauna and megafauna, megafauna and fish and fish and microzooplankton. However, the employed diversity metrics varied between communities, occasionally showing negative correlations. We suggest that the species composition and diversity of these communities reflect different environmental gradients and sources of heterogeneity, and there- fore none of them can be used as a surrogate for ecosystem biodiversity in the context of marine conservation planning.

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.

The purpose of this paper is to test the performance of rapid biodiversity assessment techniques in the lagoonal environment at the pan-Mediterranean scale. The multivariate techniques can produce patterns of lagoonal biodiversity along the Mediterranean. Additionally, it is shown that the polychaete inventory can preferably be used rather than the aggregation of information at the family level for the purposes of rapid biodiversity assessment. These techniques, however, appear to be weak for the environmental assessment because they cannot detect differences between the naturally disturbed and the anthropogenically impacted lagoons. Both taxonomic distinctness indices are found to be robust in providing meaningful results for rapid biodiversity/environmental assessment when the crustacean inventory and the polychaete and molluscan ones are used for the estimation of the average taxonomic distinctness and of the variation in taxonomic distinctness values, correspondingly. Conversely, information on the distribution of the macrofaunal species to the Mediterranean lagoons appears to be inadequate for the needs of such rapid biodiversity assessment at a regional scale. It is suggested that information on ecological convergence of the macrofaunal species would probably provide biodiversity indices with additional power, at least in the lagoonal environment.

An attempt is made to compare the results of different rapid biodiversity assessment techniques at the pan-Mediterranean, sectorial and local levels. A uniform multivariate pattern exists at the pan-Mediterranean and national (sectorial) levels: lagoons can be different when they host only a few species, but as species numbers increase, lagoons become homogenous in composition. Multivariate techniques cannot distinguish anthropogenically-impacted lagoons from those, which are naturally disturbed. In the pan-Mediterranean context it is the higher taxonomic levels, but in the national and local context it is the most abundant macrobenthic groups (polychaetes, molluscs and crustaceans) and meiobenthos which provide patterns closest to that derived from the species level. Taxonomic distinctness indices applied to polychaete and mollusc inventories provide meaningful results at most levels and scales of observation. These indices seem to be robust enough to discriminate anthropogenically impacted from naturally disturbed lagoons.

Ten alien species were recorded in a first-time survey of the benthic biodiversity of the upper sublittoral at Sigri Bay (Lesvos Island, north-eastern Aegean Sea). The record of the mollusc Syrnola fasciata is the first in Hellenic territorial waters. The records of the brown alga Stypopodium schimperi, the bivalve Septifer cumingii, the gastropods Syrnola fasciata and Smaragdia souverbiana and the bony fish Siganus luridus constitute evidence for a further northwards extension of their geographic ranges in the Aegean Sea. The record of Cerithium scabridum is the first in Lesvos Island and partially fills the gap in the distribution of the species in the eastern Aegean Sea. We also recorded the green alga Caulerpa cylindracea, the angiosperm Halophila stipulacea and the bivalve Pinctada imbricata radiata, which are widely distributed in the eastern Mediterranean. The polychaete Marphysa adenensis, which was also found at Sigri Bay, has recently been reported for the first time from the Mediterranean as a cryptogenic species.

According to reports, the following 16 species have extended their distribution to other Mediterranean areas or have made a new appearance in other regions. The first category includes the following organisms: The rare and common Indo-Pacific seaweed Codium arabicum (Lebanese coasts), the acari Thalassarachna affinis (Marmara Sea), and the non-indigenous nudibranch Flabellina rubrolineata , which has also been found in many other areas of the Aegean Sea. In addition, the rare sea slug Thecacera pennigera (Piccolo of Taranto), the fangtooth moray Enchelycore anatina (National Marine Park of Zakynthos, Ionian Sea), the carangid Seriola fasciata (Gulf of Antalya), Lagocephalus sceleratus (SE. Ionian Sea), the reticulated leatherjacket Stephanolepis diaspro s (Slovenia, N. Adriatic Sea), the marbled stingray, Dasyatis marmorata (NE Levantine), the starry smooth-hound Mustelus asterias (Iskenderun Bay, NE Mediterranean), the cephalopod Ommastrephes bartramii (Ionian Sea) have also been reported. The Atlantic crab Dyspanopeus sayi has expanded to many Italian areas and the blue crab Callinectes sapidus to a lake in N. Greece and in the S. Adriatic Sea. Finally, Farfantepenaeus aztecus has been found in the Ionian Sea, thus showing its wide expansion in the Mediterranean. The larval stages of Faccionella oxyrhyncha have been found, after many years, in the Aegean Sea and the first report of an existence on intersexual acari Litarachna duboscqi in Split (Adriatic Sea) was reported.

The deep sea molluscan fauna of the Cretan Sea (Eastern Mediterranean) was investigated from living material collected by the R/Vs“AEGAEO” and“PHILIA” cruises in the framework of the MTP/MAST EU research programme CINCS, carried out by the I.M.B.C. Examination of the deep sea benthos, with particular reference to the phylum Mollusca, over a grid of stations from depths between 40 and 1570 m, revealed the presence in the area of a diverse fauna consisting of 147 species belonging to 6 different classes. Large numbers of species (44) are new elements of the molluscan fauna of the Cretan Sea while another 4 species (1 Polyplacophora, 2 Gastropoda, and 1 Bivalvia) have not been reported so far from the Aegean or the Eastern Mediterranean. The majority of the species exhibit a wide bathymetrie distribution, from the continental shelf region to the bathyal slope, and only a few species are considered as deep sea species (reported only from the latter). The faunal composition of the collected material from the studied area (in depths over 200 m) clearly demonstrates the presence in the Cretan Sea of theAbra longicallus-association, already reported in other deep basins of the Mediterranean where similar research has been carried out. However, the presence of the bivalveNuculoma aegeensis even in the shallow waters of the continental shelf strengthens the opinion of other authors (Janssen 1989;Dounas &Koukouras 1992) that theNuculoma aegeensis “facies” of the above association is not found as deep asdi Geronimo (1974) had claimed (1500 m). Most of the deep sea mollusc species collected from the Cretan Sea are distributed from the Mediterranean to the Atlanto-Mediterranean and Boreal province while no species with an Indo-Pacific origin (Lessepsian immigrants) were found. Taking into consideration results of studies on the molluscan fauna from shallow waters of the Cretan Sea (Koutsoubas et al. 1992) it can be concluded that this part of the Mediterranean could not be considered as an impoverished system, as it hosts a rather enriched and diverse molluscan fauna numbering more than 400 species.

The annelid community of a shallow Mediterranean lagoon (Gialova Lagoon, Ionian Sea) was studied on a seasonal basis. Out of the 39 species identified eight are reported for the first time from the central Mediterranean. The dominant species were the polychaetes Capitella capitata, Neodexiospira pseudocorrugata, Malacoceros fuliginosus, Perinereis cultrifera, Hediste diversicolor, Heteromastus filiformis and the oligochaete Limnodriloides maslinicensis. Uni- and multivariate methods were employed to study the community structure. The coenocline observed is strongly related to the degree of isolation; its main features (i.e. number of species, density, geometric abundance and size-classes) in space and time are presented and discussed in detail. The distribution pattern of the annelid community has been found to be governed by a different set of environmental factors in each season. Although this narrow lagoonal habitat suffers severe dystrophic episodes it manages to recover, demonstrating a seasonal community pattern.

Fiorenza Micheli ... et al. -- 17 páginas, 7 figuras, 3 tablas, Spatial prioritization in conservation is required to direct limited resources to where actions are most urgently needed and most likely to produce effective conservation outcomes. In an effort to advance the protection of a highly threatened hotspot of marine biodiversity, the Mediterranean Sea, multiple spatial conservation plans have been developed in recent years. Here, we review and integrate these different plans with the goal of identifying priority conservation areas that represent the current consensus among the different initiatives. A review of six existing and twelve proposed conservation initiatives highlights gaps in conservation and management planning, particularly within the southern and eastern regions of the Mediterranean and for offshore and deep sea habitats. The eighteen initiatives vary substantially in their extent (covering 0.1–58.5% of the Mediterranean Sea) and in the location of additional proposed conservation and management areas. Differences in the criteria, approaches and data used explain such variation. Despite the diversity among proposals, our analyses identified ten areas, encompassing 10% of the Mediterranean Sea, that are consistently identified among the existing proposals, with an additional 10% selected by at least five proposals. These areas represent top priorities for immediate conservation action. Despite the plethora of initiatives, major challenges face Mediterranean biodiversity and conservation. These include the need for spatial prioritization within a comprehensive framework for regional conservation planning, the acquisition of additional information from data-poor areas, species or habitats, and addressing the challenges of establishing transboundary governance and collaboration in socially, culturally and politically complex conditions. Collective prioritised action, not new conservation plans, is needed for the north, western, and high seas of the Mediterranean, while developing initial information-based plans for the south and eastern Mediterranean is an urgent requirement for true regional conservation planning, The workshop in which this work was initiated was funded by The Australian Research Council Centre of Excellence for Environmental Decisions (www.ceed.edu.au). The Greek television channel SKAI (www.skai.gr/tv/) covered workshop participants’ accommodation. The Biodiversity Research Group provided the workshop with consumables. FM acknowledges the support of the Pew Marine Trust and the Oak Foundation. SG was supported by the project "NETMED" cofinanced by the European Union and the Greek State. MC was funded through the Ramon y Cajal fellowship program of the Spanish Government. DK was funded through the MedPAN Network (www.medpan.org). SF was also supported by the European Community’s 7th Framework Programme (FP7/2007–2013) under Grant Agreement No. 287844 for the project ’Towards COast to Coast NETworks of marine protected areas (from the shore to the high and deep sea), coupled with sea-based wind energy potential (COCONET)’. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Aim Tracking the dispersal patterns and habitat use of migratory species is necessary to delineate optimal areas for protection, with large sample sizes being more representative of the population. Here, we examine the dispersal patterns of a key Mediterranean loggerhead turtle (Caretta caretta) breeding population to identify priority foraging sites for protection. Location Zakynthos Island, Greece and the wider Mediterranean. Method We examined the dispersal patterns and foraging sites of 75 adult loggerheads (n = 38 males and 37 females) tracked from the breeding area of Zakynthos Island (Greece) from 2004 to 2011. We then combined our data with published sea turtle literature to identify key foraging sites for protection. Results While both males and females exhibited similar dispersal patterns, about 25% males remained 200 km. Integration of our data with the wider literature isolated 10 core sites in proximity to existing protected areas, which could potentially protect 64% of the Zakynthos population, while five sites support individuals from at least 10 other loggerhead breeding populations. Main conclusions Due to the widespread availability of neritic foraging grounds across the Mediterranean, sea turtles from Zakynthos exhibit disparate dispersal patterns. However, protecting only a few objectively defined important sites can encompass a large proportion of the foraging areas used and hence have considerable conservation benefit.

Eight opisthobranch species of the orders Sacoglossa and Nudibranchia found in different areas of the Aegean Sea, and representing new records for the Eastern Mediterranean are presented. Additional information is given on the morphology, the habitat, and the geographical distribution of each species.

Five opisthobranch species (Pleurobranchus testudinarius, Caloria elegans, Dondice banyulensis, Janolus cristatus and Flabellina babai) unrecorded up-to-date in the Greek seas along with Scyllaea pelagica and Notarchus punctatus species reported after more than a century from their first finding in the Mediterranean (southern Aegean—Milos and Serifos Islands) by Forbes (1844), and zoogeographical and ecological details, are presented in this study. Scyllaea pelagica, N. punctatus and F. babai seem to have a narrow distribution in Greek waters while the rest of the species seem well established similar to what has been reported from other seas in the western Mediterranean or the Atlantic.

Marphysa is one of the largest genera in the family Eunicidae, containing 76 valid species. However, among them there are only five species that share the diagnostic characters of having only composite falcigers in inferior setae and branchiae confined in the anterior body. These species are relatively rare and less described while in their original descriptions their differentiation is mainly based on features believed to be age-specific today. In this study, the type-materials of M. adenensis, M. purcellana and M. gemmata have been re-examined and re-described with illustrations. For M. adenensis, new material from the Mediterranean Sea was also examined, where this group has not been recorded up to date. The above species were compared to each other and new differential characters are being highlighted. A revised key for the Marphysa species found in the Mediterranean is also provided.

Recognising the need for data gathering at taxon level besides the taxa of commercial interest and those listed as endangered in the Protocol of the Barcelona Convention, but still exploited by Man, the present study attempts to gather and review the available scientific information on molluscs of minor commercial importance in order to assist in the adequate management and protection of their populations. Forty one species (18 gastropods, 13 bivalves, and 10 cephalopods) of minor commercial interest are treated in the present work with details on their biogeographic distribution, exploitation and conservation status in Hellas. Apart from a few species (e.g., Pinna nobilis, Lithophaga lithophaga, Donacilla cornea), and these only at a local scale, there is no population assessment in Hellenic seas. The existing legislation for eleven of these species is not enforced in practice, and seems insufficient to guarantee their conservation. It is suggested that targeted collection data, networked nationally and internationally, should be promoted so this invaluable source of biodiversity information can be accessed for conservation and planning purposes.