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Recently, despite long-term systematic research of the Adriatic Sea ecosystem, the necessity to improve the existing protection of commercially exploited species occurred since the status of many renewable marine stocks were not in good state. In order to realize that review of scientific knowledge gather within the last two decades was required. In this paper emphasis has been placed on all the scientific knowledge concerning the reproductive biology, spawning and nursery grounds of four ecologically and economically important Adriatic fish species – sardine Sardina pilchardus, anchovy Engraulis encrasicolus, European hake Merluccius merluccius, Common pandora, Pagellus erythrinus. Main aim of this review was to establish new scientific platform that in near future should result with better conservation measures that will insure long-term sustainability of exploited marine living resources., U novije vrijeme, unatoč dugoročnom sustavnom istraživanju ekosustava Jadranskog mora, a s obzirom da status većine obnovljivih morskih stokova nije u biološki dobrom stanju biomase, pojavila se nužnost proširenja postojeće zaštite komercijalno iskorištavanih vrsta. Kako bi se to realiziralo bilo je potrebito napraviti pregled svih znanstvenih spoznaja stečenih u posljednja dva desetljeća. Tako je u ovom preglednom radu naglasak stavljen na znanstvene činjenice vezane uz reproduktivnu biologiju kao i mrijestilišta i rastilišta četiriju ekološki i ekonomski važnih jadranskih vrsta riba – srdela Sardina pilchardus, brgljun Engraulis encrasicolus, oslić Merluccius merluccius, arbun Pagellus erythrinus. Glavni cilj ovog preglednog rada je bio stvoriti novu znanstvenu platformu koja bi u bliskoj budućnosti trebala rezultirati boljim mjerama očuvanja koje bi nadalje rezultirale dugoročnim održivim iskorištavanjem živih morskih resursa u Jadranu.

The Mediterranean Sea shows a trend of increasing temperature and decreasing productivity from the western to the eastern basin. In this work we investigate whether this trend is reflected in the cephalopod assemblages found throughout the Mediterranean. Data obtained with bottom trawl surveys carried out during the last 22 years by EU Mediterranean countries were used. In addition to analysing spatial differences in cephalopod assemblages, we also analysed putative temporal changes during the last two decades. For this purpose, the basin was spatially divided into bioregions, the trawling grounds were subdivided into depth strata, and the dataset was split into two time series of 11 years each. All analyses were done using PRIMER software. The species richness did not vary with the longitudinal gradient, though in most bioregions it showed a mild decrease with depth before plummeting in the deepest waters. Cluster analysis revealed four different bathymetric assemblages in all bioregions. Despite the contrasting conditions between basins and the claims of biodiversity loss, our study revealed that spatial and temporal differences during the last two decades were restricted to changes in the relative abundance of species from a common pool of species inhabiting the whole Mediterranean. El mar Mediterráneo muestra un patrón de aumento de la temperatura y disminución de la productividad de la cuenca occidental a la oriental. En este trabajo se investiga si este patrón se refleja en las comunidades de cefalópodos que habitan el Mediterráneo. Se utilizaron datos obtenidos en campañas de arrastre de fondo realizadas durante los últimos 22 años por la mayoría de países mediterráneos de la UE. Junto con el análisis de las diferencias espaciales en las comunidades de cefalópodos, también se analizaron cambios temporales durante las dos últimas décadas. Para ello, la cuenca se dividió espacialmente en diferentes bioregiones, mientras que el conjunto de datos se dividió en dos series temporales de 11 años cada una. Todos los análisis se realizaron utilizando el software PRIMER. La riqueza específica no varió con el gradiente longitudinal, aunque en la mayoría de las bioregiones mostró una leve disminución con la profundidad antes de desplomarse en el estrato más profundo. El análisis cluster reveló cuatro comunidades batimétricas diferentes en todas las bioregiones. A pesar de las contrastadas condiciones ambientales entre las cuencas y las afirmaciones de pérdida de biodiversidad, nuestro estudio reveló que las diferencias espaciales y temporales durante las dos últimas décadas se limitaron a cambios en la abundancia relativa de las especies a partir de un conjunto faunístico común que habita todo el Mediterráneo.

The main characteristics concerning the distribution of two of the most important decapod crustaceans of commercial interest in the Mediterranean Sea, the deep-water rose shrimp, Parapenaeus longirostris, and the Norway lobster, Nephrops norvegicus, are studied in the European Mediterranean waters. The study is based on data collected under the MEDITS trawl surveys from 1994 to 2015 from the Gibraltar Straits to the northeastern Levantine Basin (Cyprus waters). The observed differences can be interpreted as different responses to environmental drivers related to the differing life history traits of the two species. In fact, N. norvegicus is a long-living, benthic burrowing species with low growth and mortality rates, while P. longirostris is an epibenthic, short-living species characterized by higher rates of growth and mortality, Se investigaron las características de la distribución de dos de los crustáceos decápodos más importantes a nivel comercial del mar Mediterráneo, la gamba de altura, Parapenaeus longirostris y la cigala, Nephrops norvegicus, en aguas mediterráneas europeas. El presente estudio se basa en datos recopilados en las campañas de pesca experimental de arrastre MEDITS, relizadas de 1994 a 2015 desde el estrecho de Gibraltar hasta la cuenca levantina nororiental (aguas de Chipre). Las diferencias observadas en el patrón de distribución se pueden interpretar como distintas respuestas a factores ambientales relacionados con los diferentes rasgos del ciclo vital de las dos especies. De hecho, N. norvegicus es una especie bentónica de vida larga, con bajas tasas de crecimiento y mortalidad, mientras que P. longirostris es una especie epibentónica de vida corta, caracterizada por tasas más altas de crecimiento y de mortalidad

Additional records of the Norwegian skate Dipturus nidarosiensis (Storm, 1881)from the Adri-atic Sea are reported. Two specimens were collected in the southern Adriatic Pit in 2008 and 2010, respectively. The records reported herein improve our knowledge on the distribution of a rarely encountered, deep water species D. nidarosiensis, whose presence has only recently been confirmed in the Mediterranean Sea.

European hake (Merluccius merluccius) is one of the most economically important fish for the Mediterranean Sea. It is an important predator of deep upper shelf slope communities currently characterized by growth overexploitation: the understanding of hake's diet might support next generation management tools. However, all current European hake diet studies depend on the morphological identification of prey remains in stomach content, with consequent limitations. In this study, we set up a metabarcoding approach based on cytochrome oxidase I PCR amplification and Miseq Illumina paired-end sequencing of M.merluccius stomach content remains and compared the results to classic morphological analyses. A total of 95 stomach contents of M.merluccius sampled in the North-Central Adriatic Sea were analyzed with both the metabarcoding and morphological approaches. Metabarcoding clearly outperformed the morphological method in the taxonomic identification of prey describing more complex trophic relationships even when considering the morphological identification of 200 stomach contents. Statistical analysis of diet composition revealed a weak differentiation among the hake's size classes, confirming an opportunistic feeding behavior. All the analyses performed showed the presence of a core of shared prey among the size classes and a cloud of size-specific prey. Our study highlights the exceptional potential of metabarcoding as an approach to provide unprecedented taxonomic resolution in the diet of M.merluccius and potentially of other marine predators, due to the broad-spectrum of detection of the primers used. A thorough description of these complex trophic relationships is fundamental for the implementation of an ecosystem approach to fisheries.

Dye pollution represents an important environmental concern, especially from textile industries in the South of Asia. On the other hand, biomass accumulation derived from mussel processing in alimentary industries is also an environmental problem. In this research, these two environmental issues are addressed by proposing the reuse of mussel's protein anchoring threads, the byssus, as disposable material for dye water removal. The byssus was selected as substrate because it contains a distinctive variety of functional groups that can be exploited for diverse chemical interactions. This material was utilized in its native metaled state and in the de-metaled one, in order to study how the chemical state of the functional groups influences the adsorption properties of both anionic and cationic aromatic dyes. The results of comparative experiments of adsorption showed a higher uptake in the native metaled byssus for a model cationic dye, methylene blue, while the de-metaled byssus showed a higher uptake for a model anionic dye, Eosin Y. These results are considered in light of different uptake mechanisms, supported by the analyses of isotherm model parameters, in which diverse functional groups are involved as a function of substrate and dye chemical states.

The main characteristics concerning the distribution of two of the most important decapod crustaceans of commercial interest in the Mediterranean Sea, the deep-water rose shrimp, Parapenaeus longirostris, and the Norway lobster, Nephrops norvegicus, are studied in the European Mediterranean waters. The study is based on data collected under the MEDITS trawl surveys from 1994 to 2015 from the Gibraltar Straits to the northeastern Levantine Basin (Cyprus waters). The observed differences can be interpreted as different responses to environmental drivers related to the differing life history traits of the two species. In fact, N. norvegicus is a long-living, benthic burrowing species with low growth and mortality rates, while P. longirostris is an epibenthic, short-living species characterized by higher rates of growth and mortality.

This study describes the distribution patterns and population structure of greater weever in the Adriatic Sea. Biological data were obtained during MEDITS surveys in the spring-summer period. The aim of this study is to provide recent data for better understanding of species biology and to create basis for fisheries management based on ecological approach.

Relationships among catch, fishing effort, and measures of fish stock abundance have several implications for fisheries research. In this context, spatial and seasonal aspects are of significant importance for management decisions, especially when effort regulation schemes are used. In this paper, the multispecies trawl fishery in the Northern and Central Adriatic Sea was investigated, taking into account the heterogeneous distribution of fish stocks. Two approaches are presented depending on the availability (or not) of fishery-independent indices of stock abundance. The empirical results indicate that (i) aggregation and targeting behaviours affect catches by modifying the relationship between abundance and catch per unit effort and (ii) these relationships are not homogenous across space. Data from the Adriatic Sea is still insufficient to guarantee reliable estimations. However, these preliminary results call into question management decisions being made on the basis of catch per unit effort. Furthermore, the high heterogeneity between the northern and central areas of the sea basin calls for the adoption of spatially explicit management systems.

Leptocephali are the characteristic larval forms of the superorder Elopomorpha, very difficult to identify at the species level and sharing few or no characters with the respective adult forms. In this study we used DNA barcoding coupled to classical taxonomy for the species identification of Chlopsis bicolor (Rafinesque, 1810) leptocephali. In the Mediterranean some individuals of C. bicolor in developmental stage, collected along the Sicilian shore of the Messina Strait, were already identified and their detailed morphological descriptions were provided. However, very few specimens of C. bicolor from the Adriatic Sea have been reported and this work represents the first record of its larval form. Three leptocephali of the false moray C.bicolor were morphologically identified among other eel larvae collected during scientific cruises performed in South Adriatic between 2010 and 2012. Moreover we sequenced a 655bp region of COI (cytochrome c oxidase I) in addition to classical taxonomy to provide a larval barcode voucher for species identification. COI barcoding has proven to be successful in larval fish identification, revealing also a good performance as a diagnostic method for the identification of leptocephali. Anyway, the limited number of anguilliform species annotated in the reference databases (Barcode of Life Data Systems and GenBank) allowed us to validate our barcode only at the family level (Chlopsidae). Nevertheless, the morphological description provided in this work together with the barcode sequence published in the project ‘Barcoding of the Adriatic Leptocephali’ (BAL) on the Barcode of Life Data System (BOLD, http://www.barcodinglife.org), represent a useful contribution to the knowledge of this species.

Coral reefs are the most biodiverse ecosystems of the ocean and they provide notable ecosystem services. Large-scale monitoring is necessary to understand the effects of anthropogenic threats and environmental change on coral reef habitats and citizen science programs can support this effort. Seventy-two marine taxa found in the Red Sea were surveyed by non-specialist volunteers during their regular recreational dives, using SCUBA Tourism for the Environment (STE) questionnaires. Over a period of 4-years, 7,125 divers completed 17,905 questionnaires (14,487 diving hours). Validation trials were carried out to assess the data reliability (Cronbach’s alpha >50 % in 83.6 % of validation trials), showing that non-specialists performed similarly to conservation volunteer divers on accurate transect. The resulting sightings-based index showed that the biodiversity status did not change significantly within the project time scale, but revealed spatial trends across areas subjected to different protection strategies. Higher biodiversity values were found in Sharm el-Sheikh, within protected Ras Mohammed National Park and Tiran Island, than in the less-regulated Hurghada area. Citizen science programs like STEproject represent novel, reliable, cost-effective models for biodiversity monitoring, which can be sustained and embedded within long-term monitoring programmes, and extended to include a wider geographical scale, while increasing the environmental education of the public.

Leptocephali are the characteristic larvae of the superorder Elopomorpha that are difficult to identify at the species level. In this study, we used DNA barcoding (i.e. short genetic sequences of DNA used as unique species tags) coupled with classical taxonomic methods to identify leptocephali in the southern Adriatic Sea. This information will provide an assessment of the biodiversity of the eel larvae in this region. A total of 2,785 leptocephali were collected, and using external morphology were assigned to seven morphotypes: Ariosoma balearicum, Conger conger, Gnathophis mystax, Facciolella sp., Nettastoma melanurum, Dalophis imberbis and Chlopsis bicolor. Collectively, these seven morphotypes are considered to be a good proxy for the Anguilliformes community (the main order of the Elopomorpha) in the southern Adriatic Sea (to date, seven families and sixteen species have been recorded in this region). Interestingly, the higher number of G. mystax larvae collected suggests an increased abundance of this genus. To validate the morphological identifications, we sequenced 61 leptocephali (at a 655 bp fragment from the cytochrome oxidase subunit 1 mitochondrial region) and developed barcode vouchers for the seven morphotypes. Using genetic information from reference databases, we validated three of these morphotypes. Where reference sequences were unavailable, we generated barcodes for both adult and juvenile forms to provide additional genetic information. Using this integrated approach allowed us to characterize a new species of Facciolella in the Adriatic Sea for the first time. Moreover, we also revealed a lack of differentiation, at the species level, between G. mistax and G. bathytopos, a western Atlantic Ocean species. Our morphological and barcode data have been published in the Barcoding of the Adriatic Leptocephali database. This work represents the first contribution to a wider project that aims to create a barcode database to support the assessment of leptocephali diversity in the Mediterranean Sea.

Data on distribution and abundance of the knobby swimcrab Macropipus tuberculatus were collected from the by-catch during fishery-biological investigations of the trawling grounds (“Pipeta” Expedition) in the area of the northern and middle Adriatic Sea from 1985 to 1994. The area investigated was approximately 59 000 km2 of the Adriatic continental shelf at predetermined, permanent stations along ten transects over different sediment types at depths of 10 to 430 m. The data obtained (abundance index: number of specimens per km2) were analysed in relation to depth, sediment type, time of day, and the stations where the species was recorded. The highest species abundance was recorded at depths greater than 200 m and in the area of clayey “relict” sand. In the area of investigation, M. tuberculatus was the most abundant on deeper parts of the continental shelf, and especially on the shelf border and upper slope bottoms in the southernmost part of the middle Adriatic Sea.

Summary Population structure and distribution of the thornback ray, Raja clavata, L. 1758, in the northern and central Adriatic Sea were described based on data from bottom trawl surveys conducted in the area between 1996 and 2006 within the scope of the ‘MEDITS’ project. R. clavata was caught at depths between 23 and 270 m; highest abundance and density indices were recorded at a depth stratum 50–100 m. The sex ratio was close to 1 : 1. Length at first sexual maturity for both sexes was calculated. Length–weight relationships were obtained for males, females and the whole sample. Calculated parameters of the length–weight ratio showed a positive allometry for both sexes. The recent state of the population was compared with data from the 1948–49 ‘Hvar’ expedition. The comparison revealed that significant changes have occurred in distribution and abundance of R. clavata in the Adriatic Sea since the time of the ‘Hvar’ expedition. During the 1948–49 ‘Hvar’ expedition R. clavata was distributed throughout the entire continental shelf; during the 1996–2006 MEDITS expedition the species was found only in restricted areas and with much lower abundances. Significant changes also occurred in the demographic composition of the population. All described changes indicate an over-fishing of the thornback ray in the Adriatic Sea, a result of the high fishing intensity to which the species has been exposed for the past 60 years.

This study presents the first extensive investigation of echinoderm distribution in the area of mobile bottoms in the open part of the northern and middle Adriatic Sea. Five hundred and eighteen bottom trawl hauls were performed at 56 predetermined permanent stations along ten transects over different sediment types, at depths of 10 to 430 m. A total of 34 species of Echinodermata were identified (9 from the class Holothuroidea, 12 from the class Asteroidea, 4 from the class Ophiuroidea and 9 from the class Echinoidea). The list of the species, together with data on depth and sediment distribution, and the stations where individual species were found, are presented.

European hake (EH), Merluccius merluccius, is a demersal fish distributed from the North Sea and Atlantic to the Levantine Sea in the Mediterranean. EH is an important predator of deep Mediterranean upper shelf slope communities and it is currently characterised by growth overexploitation. EH adults feed mainly on fish and squids whereas the young (

DNA barcoding is a molecular tool that enables rapid and accurate identification of biological species by sequencing a short, standardized region of the mitochondrial gene cytochrome c oxidase I ( COI) as internal species tag. The aim of the present study was to use DNA barcoding in addition to classical taxonomy in order to obtain a more reliable species-identification of leptocephali, the characteristic larval forms of the superorder Elopomorpha, often difficult to identify and to match with their adult stage. Based on the examination of external morphology, meristics, and pigmentation, 2785 leptocephalus larvae collected in the Adriatic Sea between 2010 and 2012, were ascribed to 7 morphotypes, belonging to Anguilliform order (Ariosoma balearicum, Conger conger, Gnathophis mystax, Nettastoma melanurum, Dalophis imberbis, Chlopsis bicolor, Facciolella sp.) and 69 specimens were sequenced for a 655 bp region of the mitochondrial cytochrome oxidase subunit I gene (COI) to confirm the previous morphological analysis. The highly consistent results obtained revealed a good performance of COI barcoding as a diagnostic method for the identification of these larvae, but the limited number of leptocephali species annotated in the reference databases for barcode (Barcode of Life Data Systems and GenBank) allowed to validate only partially the morphological analysis. Moreover two species, Gnathophis mystax and Facciolella sp., showed unexpected outcomes. The data obtained in this work represent the first results of a wider project aimed at the creation of a new barcode database for the assessment of leptocephali diversity in the Mediterranean Sea (Barcoding of the Adriatic Leptocephali [BAL]), contributing to the knowledge of these unusual larvae and of their adult forms.

On December 26th 2004, a earthquake west of Sumatra generated a devastating tsunami. Hundreds of thousands of people fell victim. Economic losses were greatest in those countries dependant on tourism. The impact in the Maldives on persons and things was modest. Immediately following the event and notwithstanding the lack of scientific data, the mass media gave catastrophic reports on the state of coral reefs in the area. This paper reports on the first survey on coral reefs in the Maldives after the Tsunami. Ocean walls, passes, inner reefs, and shoals in the North and South Malé atolls, were surveyed two weeks after the event. Significant damage was recorded in the passes in the South Malé atoll. Our observations showed that the damage was more or less extensive depending on latitude and topography. Sri Lanka may have broken the wave’s rush, reducing the extent of the impact on northern atolls. The water’s acceleration inside the passes was so intense as to cause reef collapses. The observed damage represents a minimum fraction of the entire coral reef system. Tourist perception of the area seems unchanged. These data may be used to disseminate correct information about the state of Maldives coral reefs, which would be useful in relaunching local economy

Seahorses ( Hippocampus) live in tropical and temperate waters. Habitat degradation and fishery overexploitation have led to drastic population declines on a global scale. Population monitoring is there- fore essential to determine current status and manage conservation. In this first study in Italian waters on the geographic and ecological distribution of the two Mediterranean species, Hippocampus hippocampus and Hippocampus ramulosus ,r ecreational scuba divers were recruited and trained to report sightings. A specially formulated questionnaire was produced and distributed to scuba diving schools and centers. In the 3-year study, 2536 divers spent 6077 diving hours gathering data and completed 8827 questionnaires. Eight percent of the questionnaires showed seahorse sightings, for a total of 3061 sighted specimens, 68% of which referred to Hippocampus ramulosus .T he two species had overlapping geographic distributions. Seahorse abundance var- ied, with the northern Adriatic Sea showing greatest abundance, followed by the central-southern Tyrrhenian Sea. Seahorses were rare in the Ligurian and northern Tyrrhenian seas. Preferred habitats were shallow areas with either sandy bottoms or Posidonia oceanica (L.) Delile meadows. Seahorse distribution may be correlated with the degree of degradation of P. oceanica meadows. Resource users (the divers) were willing to take part in biological monitoring and contributed in scientific terms by collecting considerable amounts of data over short time periods and in economic terms by decreasing costs. The greatest limitation with volunteers was the difficulty in obtaining a uniformly distributed sample across time and space. We conclude that recreational divers and other resource users can play an active part in monitoring the marine environment and that the Mediterranean Hippocampus Mission may be used as a model for biodiversity monitoring.

In order to study the genetic structure of the Adriatic shared stock of red mullet (Mullus barbatus), we developed a set of dinucleotide microsatellite markers. A dinucleotide-enriched genomic library was obtained, and 6 polymorphic dinucleotide loci were successfully optimized. The markers showed high expected heterozygosity (from 0.68 to 0.92) and allele number (from 12 to 33); thus they appear to be suitable for detecting genetic differences in the population of red mullet. Four Adriatic samples were subsequently analyzed for microsatellite variation, and the results showed subtle but statistically significant genetic differentiation, indicating that the Adriatic red mullet may group into local, genetically isolated populations. No correlation between geographic distance and genetic differentiation was observed. In addition, the evidence of recent bottlenecks in the Adriatic samples indicates that the observed population subdivision might reflect random local allelic variations, generated by reproductive success, survival rates, or fishing pressure.

In the semienclosed Adriatic Sea, the shared stocks of the cephalopods Loligo vulgaris and Sepia officinalis represent important marine fisheries resources exploited by all coastal countries. The improving of knowledge on the demographic features of these shared stocks is internationally relevant for adopting responsible management and conservation of these marine resources. Analyses of microsatellite variation in geographical samples collected from all parts of the Adriatic Sea were performed using arrays of species-specific di-nucleotide and tri-nucleotide loci. In L. vulgaris the level of genetic variability was consistent with that observed in other loliginid species, whereas the S. officinalis stock showed a microsatellite variation markedly lower than that estimated for the Atlantic and Mediterranean populations collected around the Iberian peninsula. The weak spatial genetic differentiation, the discordant results of the genetic divergence estimators and the lack of any geographical cline in the spatial genetic differences suggest the occurrence of single genetically homogeneous populations within the Adriatic stocks of both species, recommending a coordinated management of the squid and cuttlefish by the Adriatic fishing countries. On the contrary, significant differences detected in temporal replicates of S. officinalis might suggest that allelic frequency can change relating to reproductive behaviour.

The Northeast Atlantic and Mediterranean skates (Rajidae) showed remarkable species diversity but with high morphological and ecological conservatism. Since skates are particularly vulnerable to the bottom trawl fishery, species-specific demographic surveys as well as studies defining life history and evolutionary traits are important in prioritising conservation programs. However, the identification of juveniles and adults of some species may be difficult using referenced guidelines and identification keys. Therefore, we attempt to develop markers for species identification through the parallel analysis of a 16S rDNA gene sequence and of several morphological characters on 135 individuals collected by trawl surveys in the Adriatic Sea and putatively assigned to six taxa. Species-specific haplotypes were defined for Raja miraletus, Raja montagui, Dipturus oxyrinchus, since a solid accordance between species boundaries and well-differentiated haplotypes was observed. Comparative analysis of 16S rDNA sequences allowed the identification of three juvenile specimens of Leucoraja circularis, a species that rarely occurs in the Adriatic Sea. On the contrary, morphological traits and haplotype distribution were largely discordant in Raja asterias and R. clavata. While all putative R. clavata individuals showed a unique haplotype (H-CLA), only 8 of 30 putative R. asterias individuals possessed a second weakly divergent haplotype (H-AST). The remaining 22 R. asterias carried the H-CLA. The multivariate analyses of morphometric and meristic characters in putative R. clavata and R. asterias revealed the clustering of individuals regardless of haplotypes. However, a bimodal distribution of R. asterias and R. clavata samples would suggest that two separated taxa might exist, both sharing the two 16S rDNA haplotypes. The haplotype distribution appeared to be significantly correlated only to the standardised disc length/total length (DL/TL) variation. Three alternative explanations may support this scenario: (i) an incomplete lineage sorting process in two morphologically yet distinct taxa; (ii) a recent hybridisation between the two taxa; (iii) the two taxa are morphologically plastic species and all considered morphological characters may be misleading in discriminating between them at all maturity stages, except for the DL/TL. However, further analyses on larger data sets and using molecular key markers (i.e. nuclear genes) will be needed to definitely resolve the status of these taxa. Molecular relationships among rajid taxa are largely consistent with systematics based on internal and external anatomical features. This multidisciplinary study contributed to defining the pattern of species diversity and abundance of rajids in the Adriatic Sea.

On the basis of trawl survey data collected during the MEDITS project (1994-1999), the distribution of Mediterranean hake populations was described in coastal areas corresponding to about three quarters of both the latitudinal and longitudinal extensions of the Mediterranean Sea, and in the 0-800 m range. Abundance and biomass indices (in terms of number and kg per km2) are presented in 15 geographical sectors and 40 subareas from the Alborán Sea to the Aegean Sea. A statistical analysis by generalized linear modelling performed on such indices per main national blocks (Greece, France, Italy and Spain), and considering the effects of the six years of sampling and the depth, showed that biomass increased from west to east, while for all areas the most significant depth effect appeared between 100 and 200 m, corresponding to the depth range that hosts most of the summer nursery areas. The overall size-frequency distributions in shelf and slope waters, average sizes and total mortality coefficient Z per sector showed that the bulk of the MEDITS samples consisted of young individuals and, with only a few exceptions (western Sardinia, central Aegean), a generalized condition of growth overfishing was apparent. However, no negative trend was found, either in biomass or in average size of fishes, during the six years of the present study. Recruitment patterns were studied by distinguishing the youngest fish as Gaussian groups (modal length from 6 to 9 cm total length) in length-frequency distributions of each subarea and main stratum (shelf and slope). Considering the timing of MEDITS surveys (May-July), this approach emphasised the nurseries in the northern part of the western Mediterranean (Gulf of Lions, Ligurian Sea, northern Tyrrhenian Sea) and in the northern central Mediterranean, where recruitment occurs mainly during spring. On the other hand, few recruits were found in part of the central and particularly in the eastern Mediterranean, where recruitment occurs mainly in summer. MEDITS recruitment patterns therefore gave support to distinctions among Mediterranean hake populations, previously suggested on the basis of vertebral counts and other morpho-physiological, albeit fragmentary, data. In particular the central Mediterranean hake populations do not seem to be homogeneous, with an Adriatic unit very close to the northwestern one. The MEDITS experience therefore suggests that future management measures could take into account both general and regional patterns, the latter concerning mainly the younger fraction of the populations., No disponible

Nine common sole Solea vulgaris samples from five fishery Management Units (MUs) of the central Mediterranean exhibited differences in a control region sequence marker. Parsimony network showed two low-divergent haplotype phylogroups. The former predominated in samples from the Ligurian, Tyrrhenian, Adriatic and north-western Ionian Seas (MUs 9, 10, 17, 18 and northern part of 19, respectively), whereas the latter was abundant in the south-western Ionian (southern part of MU 19). The geographical clustering of maternal lineages accounts for population structuring and indicates geographical isolation of common sole stocks in the Mediterranean. Several life-history traits of common sole and hydro-geographical features of the basin might support this pattern of differentiation. Haplotype frequency differences were detected among samples either from different MUs or within the same MU. This situation indicates the presence of partially subdivided or nearly panmictic population units, whose exploitation should be based on appropriate bio-ecological features. The usefulness of control region sequence marker enhances the routinely use of the genetic stock structure analysis in low-dispersal demersal marine resources.

Fisheries management systems based on Transferable Fishing Concessions (TFC) and similar rights-based systems have been developed during the last decades in some European countries. However, at present there is not a clear view on the possible effects caused by the application of this management systems in the Mediterranean Sea. The current study, involving nine Geographical Sub-Areas (GSAs) of the Mediterranean Sea, focuses on the appropriateness, transferability and modes of applicability of a TFC system in the Mediterranean area. Three different scenarios of quota allocation have been analyzed by taking into account biological, ecological, environmental, economic and social aspects: quota in terms of resource quantity, quota as a portion of the total fishing time, quota as a portion of the total fishing capacity. Results show that the transferability of a TFC-based system to the Mediterranean context appears to be low due to the characteristics of the Mediterranean fisheries (multispecificity of resources, fishing grounds shared among different countries, multigear, importance of small-scale fisheries) and to the general lack of sound and reliable individual historical data. The study also highlights rights-based systems such as Territorial Use Rights in Fisheries (TURF) might only be applied for the exploitation of sedentary resources, such as clams. A management system based on TFC could be theoretically reasonable for anchovy fishing, where a few species are caught, even if all countries and stakeholders should be involved in the decision making process. © 2013 The Authors.

The first record of the deep-sea species Chtenopteryx sicula is reported from the Adriatic Sea. Atotal of six specimens of this rare species were caught, with bottom trawl and pelagic trawl nets, in the scope of the Deep Sea Research of the bathyal fauna in the South Adriatic Pit in 2008 and 2010. Specimens were caught at depths down to 1200 m, therefore making it the deepest and northernmost finding of this species in the Mediterranean Sea. The dorsal mantle lengths of analyzed specimens ranged between 21 and 60 mm. Only in females, a visceral photophore on the ventral side of the inc sac was detected. Some new information on morphometric body and beak features was given in the paper, including the description of beak pigmentation. A number of increments in statoliths revealed that individuals were between three and five months old. A positive linear correlation between the length of statoliths and number of increments/age in days was detected. Macroscopic and histological samples of gonads proved that one specimen was sexually mature (August), four specimens were in stages of sexual maturation (May and August) and two were immature (March). The results indicated that the maturation process of the species in the South Adriatic Sea starts in spring and the full sexual maturity is reached during summer., U radu su opisani prvi nalazi dubokomorske vrste Chtenopteryx sicula u Jadranskom moru. Pridnenom i pelagičnom mrežom ulovljeno je ukupno šest primjeraka ove rijetke vrste u sklopu istraživanja dubokomorskih zajednica u južnojadranskoj kotlini 2008 i 2010. godine. Primjerci su ulovljeni na dubinama do 1200 m te predstavljaju najdublji i ujedno najsjeverniji nalaz ove vrste u Mediteranu. Dorzalna dužina plašta analiziranih jedinki kretala se od 21 do 60 mm. Samo u ženki nađeni su visceralni fotofori na ventralnoj strani vrećice sa crnilom. U radu su date nove informacije vezane uz obilježja kljuna, uključujući detaljan opis pigmentacije. Broj zona prirasta u statolitima ukazuje na starost jedinki između tri i pet mjeseci. Utvrđena je pozitivna korelacija između dužine statolita i broja zoni prirasta/starosti u danima. Makroskopski i histološki uzorci gonada potvrdili su da je jedna jedinka bila spolno zrela (kolovoz), četiri jedinke su bile u stadiju spolnog sazrijevanja (svibanj i kolovoz), a dvije su bile spolno nezrele (ožujak). Rezultati ukazuju na to da proces spolnog sazrijevanja ove vrste u južnom Jadranu počinje u proljeće, dok se puna spolna zrelost doseže tijekom ljeta.

Trawl surveys carried out in the Adriatic Sea in 1948 and 1998 provided information on the changes that occurred in the composition and distribution of demersal fish resources over the 50 years period. The main change was the decrease of elasmobranchs diversity and frequency, mostly referring to the Hypotremata group. Life history parameters appeared to be determining factors, since small sized species such as the smallspotted catshark ( S. canicula ) or the brown ray ( R. miraletus ) were frequently collected in both surveys, while bigger shark species and most other rays disappeared or were rarely found during the 1998 survey. Regarding bony fishes, common species were collected with similar frequency in both surveys; some fishery target species (e.g. the hake) have similar percentage values (biomass) in both surveys, while others (the silver scabbardfish) have increased values, and some (mainly small sized species such as red mullet) replace elasmobranchs at the top of the catches. Despite the low number of observations (two surveys only) and some sampling differences, the data provide an interesting long-term comparison.

To increase knowledge about the systematics and evolution of Mediterranean soles, we assessed mitochondrial DNA variation, molecular phylogeny, and evolution in eight species from the genera Solea, Microchirus, Monochirus, and Buglossidium by large ribosomal subunit (16S) and cytochrome b (cytb) sequence analysis. Relevant molecular features are the great variation of base composition among species at the third codon in cytb and the heterogeneity of the nucleotide substitution rate. Phylogenies recovered using 16S nucleotide and cytb amino acid sequences agree with those based on morphology in assessing monophyly of Solea species and ancestry of Buglossidium luteum, but they are against the intergeneric differentiation of Microchirus and Monochirus. Conversely, phylogenetic trees based on cytb nucleotide sequences yielded relationships among taxa regardless of their evolutionary histories. The incongruities between morphological and molecular issues suggest the need for reassessing the systematic value of some morphological characters. Approximate estimates of the divergence time of Mediterranean soleid lineages range from 40 to 13 Mya (Oligocene-Miocene), indicating an ancient origin for the group.

Within the genus Solea, four sister lineages have been evolved that actually correspond to the species S. vulgaris, S. senegalensis, S. kleini and S. lascaris. The existence of S. aegyptiaca and S. impar is not supported and these species can be synonymized under S. vulgaris and S. lascaris, respectively. This pattern of taxonomy agrees fully with that proposed by Ben-Tuvia (1990; Journal of Fish Biology 36, 947–960) based on morphological features. In addition, mtDNA data contradict the widely accepted relatedness between S. kleini and S. lascaris based on the shared enlarged forenostril on the blind side. A sample of soles clearly related to S. senegalensis was caught in the Gulf of Taranto (Ionian Sea), representing the most western finding of this species in the Mediterranean Sea.

Corrigendum: Gene-associated markers provide tools for tackling illegal fishing and false eco-certification

A meta-analysis of the straight fork lengths (herewith abbreviated as L) of 2,458,028 Atlantic bluefin tuna, Thunnus thynnus (L.), taken from 224 scientific publications and unpublished L data from scientific organizations and fishing companies spanning most of the known Atlantic and Mediterranean Atlantic bluefin tuna fisheries dating from 1605 to 2011, give L values ranging from L min = 20 cm and L max = 330 cm. The results indicate that the parameter L ∞ = 318.85 cm of the growth equation used by ICCAT's Standing Committee on Research and Statistics Atlantic bluefin tuna assessment group for the eastern stock (Lt = 318.85 [1 – e−0.093 (t + 0.97)]) lies within the confidence limits of the maximum Ls presented in the study: L max = 319.93 ± 11.3 cm, confirming that this equation perfectly fits the biology of the growth of this species. These conclusions are also valid for the equation for the western stock (Lt = 314.90 [1 – e−0.089 (t +1.13)]). The ICCAT Atlantic bluefin tuna database contains numerous records of Atlantic bluefin tuna L outside the biological feasibility, and solutions are provided to recognize and remove these outliers based on the application of fixed values of Fulton's condition factor (K) between 1.4 and 2.6 and appropriate L-W relationships to correct this situation in the future., Sí

Institutes often lack funds and manpower to perform large-scale biodiversity monitoring. Citizens can be involved, contributing to the collection of data, thus decreasing costs. Underwater research requires specialist skills and SCUBA certification, and it can be difficult to involve volunteers. The aim of this study was to involve large numbers of recreational divers in marine biodiversity monitoring for increasing the environmental education of the public and collecting data on the status of marine biodiversity. Here we show that thousands of recreational divers can be enrolled in a short time. Using specially formulated questionnaires, nonspecialist volunteers reported the presence of 61 marine taxa encountered during recreational dives, performed as regular sport dives. Validation trials were carried out to assess the accuracy and consistency of volunteer-recorded data, and these were compared to reference data collected by an experienced researcher. In the majority of trials (76%) volunteers performed with an accuracy and consistency of 50-80%, comparable to the performance of conservation volunteer divers on precise transects in other projects. The recruitment of recreational divers involved the main diving and tour operators in Italy, a popular scientific magazine, and mass media. During the four-year study, 3825 divers completed 18 757 questionnaires, corresponding to 13 539 diving hours. The volunteer-sightings-based index showed that in the monitored area the biodiversity status did not change significantly within the project time scale, but there was a significant negative correlation with latitude, suggesting improved quality in the southernmost areas. This trend could be related to the presence of stressors in the northern areas and has been supported by investigations performed by the Italian Ministry of the Environment. The greatest limitation with using volunteers to collect data was the uneven spatial distribution of samples. The benefits were the considerable amounts of data collected over short time periods and at low costs. The successful development of citizen-based monitoring programs requires open-mindedness in the academic community; advantages of citizen involvement in research are not only adding large data sets to the ecological knowledge base but also aiding in the environmental education of the public

The sand star Astropecten irregularis (Pennant, 1777) is a very common species in the Adriatic Sea. This study establishes the distribution, biomass and abundance of that species on the continental shelf of the open waters in the northern and middle Adriatic Sea based on experimental sampling by bottom trawl during 11 cruises of the “Pipeta” Expedition (1985-1994). Five hundred and eighteen bottom trawl hauls were performed at 56 predetermined permanent stations along ten transects, over different sediment types at depths of 10 to 430 m. Astropecten irregularis was recorded in 82.2% of the hauls, with the highest biomass and abundance indices at depths from 10 to 50 m. The deepest record was in a haul from 313.5 to 412.5 m depth. Even though it was recorded all over the investigated area, it was most abundant in some areas of the northernmost part of the Adriatic, and very abundant in the areas along the western coast. The highest average biomass and abundance indices were recorded on sand-silt-clay sediment, on silty sand and sandy silt and on the clayey silt and silty clay., Morska zvijezda Astropecten irregularis (Pennant, 1777) je uobičajena vrsta u Jadranskom moru. Glavni ciljevi ovog istraživanja su bili ustanoviti njezinu distribuciju, biomasu i abundanciju na kontinentskoj podini otvorenih voda sjevernog i srednjeg Jadrana na osnovi eksperimentalnog uzorkovanja pridnenom kočom za vrijeme 11 putovanja ekspedicije Pipeta (1985.-1994.). Obavljeno je 518 potega pridnenom kočom na 56 unaprijed određenih stalnih postaja uzduž deset transekata, na različitim tipovima sedimenta na dubinama od 10 do 430 m. Vrsta A. irregularis je zabilježena u 82,2% potega, s najvećim vrijednostima indeksa biomase i abundancije na dubinama od 10 do 50 m. Najdublje je zabilježena tijekom potega od 313,5 do 412,5 m. Iako je vrsta zabilježena na cijelom istraživanom području, najabundantnija je bila na nekim područjima najsjevernijeg dijela Jadrana, te vrlo abundantna na područjima uzduž zapadne obale. Najveće srednje vrijednosti indeksa biomase i abundancije su zabilježene na pijesku-siltu-glini, siltoznom pijesku i pjeskovitom siltu te na glinovitom siltu i siltoznoj glini.

Samples of Coelorinchus caelorhincus were collected by bottom trawl during MEDITS (“Mediterranean International Trawl Survey”) in June 2003 in the northern and central Adriatic Sea. A total of 175 specimens of C. caelorhincus were used for analysis, of which 90 were males, 84 females and 1 indeterminate. Pre-anal length (PAL) in males ranged between 39 and 77 mm (x¯=50.91±7.63 mm) and in females between 29 and 115 mm (x¯=55.86±16.3 mm). The length-weight relationship for the whole sample was W=0.0004PAL2.65 (r2= 0.922) indicating negative allometric growth. The age structure of C. caelorhincus was determined from sagittal otolith readings. Maximum otolith length (LO) increased proportionally to fish length (LO=2.585+0.09PAL, r2=0.946). Age ranged from 2 to 8 years, with the majority of specimens being 3 (30%) and 4 (31%) years old. The von Bertalanffy growth parameters were: L∞ = 128 mm, K = 0.105 year-1 and t0 = -1.277 year., Uzorci morskog miša Coelorinchus caelorhincus sakupljeni su pridnenom povlačnom mrežom koćom tijekom ekspedicije MEDITS (“Mediterranean International Trawl Survey”) u lipnju 2003. u sjevernom i srednjem Jadranu. Za analizu je spremljeno sveukupno 175 primjeraka C. caelorhincus od čega 90 mužjaka, 84 ženke i 1 nedeterminirani primjerak. Pre-analna dužina kod mužjaka kretala se u rasponu od 39 do 77 mm (x=50.91±7.63 mm), a kod ženki od 29 do 115 mm (x=55.86±16.3 mm). Dužinsko - maseni odnos za cjelokupni uzorak iznosio je W=0.0004PAL2.65 (r2= 0.922) i ustanovljena je negativna alometrija. Starost C. caelorhincus je procijenjena očitavanjem otolita. Maksimalna dužina otolita (LO) je proporcionalna dužini tijela (LO=2.585+0.09PAL, r2=0.946). Starost se kretala od 2 do 8 godina, a većina primjeraka bila je stara između 3 (30%) i 4 (31%) godine. Von Bertalanffy parametri rasta iznosili su: L∞ = 128 mm, K = 0.105 godina-1 i t0 = -1.277.