27 research outputs found

    Patrón de abundancia espacio-temporal de la gamba de altura, Parapenaeus longirostris, y de la cigala, Nephrops norvegicus, en las aguas mediterráneas europeas

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    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

    Estabilidad de las relaciones entre las agrupaciones de peces demersales y los factores ambientales-actividad pesquera a gran escala espacio-temporal en el norte del mar Mediterráneo

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    Trawling pressure and environmental changes may affect the composition of fish assemblages. Our knowledge on large spatio-temporal patterns of demersal fish composition remains incomplete for the Mediterranean Sea. We investigated (1) the spatio-temporal stability of demersal assemblages, (2) the relationships between these assemblages and potential structuring factors (trawling pressure and environmental conditions) in order to assess the dynamic of the assemblage structure at the scale of the northern Mediterranean Sea. We analysed a dataset of 18062 hauls from 10 to 800 m depth performed annually during the last two decades across 17 Geographical Sub-Areas (GSAs) (MEDITS program). A multi-table analysis (STATICO-CoA) evidenced a strong inter-GSAs stability in the organization of assemblages, with specificities for some GSAs. The most stable structuring factors were linked to combined gradients of chlorophyll a, phytoplancton carbon biomass and temperature, inversely correlated with depth, salinity and nutrient gradients (axis 1 of the STATICO-CoA compromise, 93.74% of the total variability). A common pattern linking the distribution of species to these environmental gradients was evidenced for most of the 17 GSAs. Estimate of trawling pressure showed a minor role in the organization of the assemblages for the spatial scale and years investigated (axis 2, 4.67%).La presión pesquera y los cambios ambientales pueden afectar a la composición de las agrupaciones de peces. En el Mediterráneo, nuestro conocimiento a gran escala sobre los patrones espacio-temporales de la composición de especies de peces demersales sigue siendo incompleto. Investigamos (1) la estabilidad espacio-temporal de las agrupaciones demersales (2) las relaciones entre dichas agrupaciones y los posibles factores estructurantes (presión pesquera de arrastre y condiciones ambientales) para evaluar la dinámica de la estructura de las agrupaciones en el norte del mar Mediterráneo. Analizamos un conjunto de 18062 lances entre 10 y 800 m. de profundidad realizados anualmente, durante las últimas dos décadas, en 17 sub-áreas geográficas (GSAs) (Proyecto MEDITS). El análisis multi-tablas (STATICO-CoA) evidenció una fuerte estabilidad inter-GSAs en la organización de agrupaciones, con especificidades para algunas GSAs. Los factores estructurantes más estables se relacionaron con los gradientes combinados de clorofila a, fitoplancton, carbono y temperatura, correlacionados inversamente con los gradientes de profundidad, salinidad y nutrientes (eje 1 del STATICO-CoA, 93.74% de la variabilidad total). En la mayoría de las GSAs encontramos un patrón común que vincula la distribución de las especies a estos gradientes ambientales. La estimación de la presión pesquera de arrastre mostró un papel menor en la organización de las agrupaciones para la escala espacial y los años investigados (eje 2, 4.67%)

    Otolith shape analysis as a tool for stock identification of two commercially important marine fishes: Helicolenus dactylopterus and Merluccius merluccius

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    Stock identification studies are essential to understanding fish population structure and connectivity across wide geographical areas, and thus contribute to efficient fisheries management. The blackbelly rosefish, Helicolenus dactylopterus, and European hake, Merluccius merluccius, are two economically important marine fishes, but there are still gaps in knowledge regarding their present stock structure. Our objective was to assess the ability of otolith shape to define stock structure for the two species along the Northeastern Atlantic Ocean and the Mediterranean Sea, based on samples from eight and seven areas, for blackbelly rosefish and European hake, respectively. Shape analysis was obtained through Wavelet analysis. Canonical analysis of principal coordinates provided significant evidence for different population units with a clear separation between the Atlantic and Mediterranean populations for both species. However, random forest procedures indicated that the discrimination power varied with species and locations. For blackbelly rosefish, various Atlantic populations were more evident than for European hake. Overall, the usefulness of otolith shape to delineate stock structure of two species with distinct life history traits across a broad spatial region from the mid-Atlantic isles to the polar region, as well as the Mediterranean was demonstrated. Moving forward, it will be key to align our growing understanding of population structure with our increasing knowledge on species’ biological traits to ensure management units reflect population structure.Samples from Levantine Sea were collected under the Cypriot National Data Collection Programme (Regulations EC 2017/1004, 665/2008 and Decisions 2019/909, 2019/910, 2019/910), co-funded by the Operational Programme “Thalassa” 2014–2020 financed by EMFF 2014–2020. Ana Vaz is funded by national funds (OE), through Fundação para a Ciência e Tecnologia, I.P. (FCT), in the scope of a PhD Grant (SFRH/BD/137862/2018). Susanne Tanner was supported by FCT through institutional funding UIDP/04292/2020, LA/P/0069/2020 and research contract (2021.02710. CEECIND). Milene Alexandra Guerreiro is funded by national funds (OE), through Fundação para a Ciência e Tecnologia, I.P. (FCT), in the scope of a PhD Grant (2020.06503. BD). Filipe Martinho was also funded by FCT in the scope of Decree-Law 57/2016 and supported by institutional funding - Centre for Functional Ecology - Science for People and the Planet (CFE; UIDB/04004/2020), financed by FCT/MCTES through national funds (PIDDAC), and Associate Laboratory TERRA (LA/P/0092/2020).Peer reviewe

    New records of rare species in the Mediterranean Sea (May 2020)

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    This Collective Article presents information about 17 taxa belonging to four Phyla (one Cnidaria, two Arthropoda, four Mollusca, and ten Chordata) and extending from the Western Mediterranean to the Levantine Sea. The new records were reported from nine countries as follows: Algeria: first published records of the clingfishes Apletodon dentatus and Lepadogaster lepadogaster after 1955; France: first record of the tripletail Lobotes surinamensis in French Mediterranean waters; Italy: new records of the rare bonito Orcynopsis unicolor and the recently described nudibranch Elysia rubeni from Sicily; first records of the parasitic cirriped Sacculina eriphiae and the nudibranch Dondice trainitoi in the Ionian Sea; first record of the nudibranch Taringa tritorquis in the Mediterranean Sea; first record of the tripletail Lobotes surinamensis in the North Ionian Sea; first documented record of the cephalopod Macrotritopus defilippi in the Adriatic Sea; Slovenia: first record of the Mediterranean endemic cryptobenthic goby Odondebuenia balearica; Montenegro: several recent occurrences of the critically endangered bull ray Aetomylaeus bovinus in the South-eastern Adriatic Sea; Greece: records of the nudibranch Dondice trainitoi in the Eastern Mediterranean Sea; new record of the occurrence of the Mediterranean spearfish Tetrapturus belone from Greece (Rhodes Island); Turkey: recent captures of the vulnerable ocean sunfish Mola mola, caught by purse-seine, in the Aegean Sea and the Dardanelles; new record of the luvar Luvarus imperialis along the Aegean coast of Turkey; Cyprus: first record of the habitat-forming hydroid Lytocarpia myriophyllum, often in considerable densities; first confirmed record of the agujon needlefish Tylosurus imperialis; Syria: first record of the decapod Ethusa mascarone

    Análisis exploratorio de los datos de determinación de edad de Mullus barbatus en el Mediterráneo

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    The uncertainty in age estimation by otolith reading may be at the root of the large variability in red mullet (Mullus barbatus) growth models in the Mediterranean. In the MEDITS survey, red mullet age data are produced following the same sampling protocol and otolith reading methodology. However, ageing is assigned using different interpretation schemes, including variations in theoretical birthdate and number of false rings considered, in addition to differences in the experience level of readers. The present work analysed the influence of these variations and the geographical location of sampling on red mullet ageing using a multivariate approach (principal component analysis). Reader experience was the most important parameter correlated with the variability. The number of rings considered false showed a significant effect on the variability in the first age groups but had less influence on the older ones. The effect of the theoretical birthdate was low in all age groups. Geographical location had a significant influence, with longitude showing greater effects than latitude. In light of these results, workshops, exchanges and the adoption of a common ageing protocol based on age validation studies are considered fundamental tools for improving precision in red mullet ageing.La incertidumbre en la estimación de la edad mediante la lectura de otolitos puede ser la principal causa detrás de la gran variabilidad existente en los modelos de crecimiento del salmonete (Mullus barbatus) en el Mediterráneo. En la campaña MEDITS, los datos de edad del salmonete se generan siguiendo el mismo protocolo de muestreo y metodología de lectura de otolitos, aunque la asignación de la edad se lleva a cabo usando distintos esquemas para la interpretación de las lecturas, incluyendo variaciones en la fecha teórica de nacimiento y en el número de anillos considerados falsos, además de las diferencias existentes en cuanto al nivel de experiencia de los lectores. En este trabajo, la influencia de las variaciones en los esquemas de interpretación, el nivel de experiencia de los lectores, y la localización geográfica de las muestras, sobre la determinación de la edad en el salmonete se analiza mediante una aproximación multivariante (Análisis de Componentes Principales). La experiencia de los lectores fue el parámetro más correlacionado con la variabilidad. El número de anillos considerados falsos mostró un efecto significativo sobre la variabilidad de los primeros grupos de edad, mientras que su influencia sobre los más viejos fue menor. El efecto de la fecha teórica de nacimiento tuvo poca importancia en todos los grupos de edad. La localización geográfica tuvo una influencia significativa, con la longitud mostrando mayores efectos que la latitud. Teniendo en cuenta estos resultados, los grupos de trabajo e intercambios de otolitos así como la adopción de un protocolo de asignación de edad común basado en estudios de validación de edad, se consideran herramientas fundamentales para mejorar la precisión en la determinación de la edad del salmonete

    New Mediterranean Biodiversity Records (November 2018)

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    In the present article, new records are given for 18 species (6 native, 9 alien and 3 cryptogenic), belonging to 5 Phyla (i.e. Chlorophyta, Cnidaria, Annelida, Mollusca and Chordata), from 8 Mediterranean countries: Spain: A large population of Polycerella emertoni reported from the Ebro Delta, the presence of pinimuricea klavereni is confirmed for the first time in the Catalan coast; Italy: the new record of Cryptonome turcica extends its distribution to the western Mediterranean Sea, the findings of Mawia benovici constitute the southernmost record of this species in the Adriatic Sea; Slovenia: second record of the alien seaslug Cuthona perca in the Mediterranean Sea; Montenegro: Styela plicata communities were recorded in Boka Kotorska Bay; Albania: the native great torpedo ray Tetronarce nobiliana recorded for the first time in Albanian waters; Greece: first record of Lagocephalus sceleratus in the Greek side of the Adriatic, the records of Cassiopea andromeda and Pterois miles are first records of these species from the Ionian Sea, the colonial ascidians Aplidium coeruleum and Didemnum protectum are recorded for the first time in the Eastern Mediterranean, an extremely abundant population of Melibe viridis is found in Messolonghi lagoon, the record of Synchiropus sechellensis is the range expansion of this species in Greek Seas, Acetabularia caliculus is recorded for the first time from Greece; Cyprus: first records of Callionymus filamentosus and Haminoea cyanomarginata from the island; Turkey: the presence of Berthellina citrina in the Mediterranean is confirmed.info:eu-repo/semantics/publishedVersio

    The Third Workshop on Population of the RDBES Data Model (WKRDB-POP3)

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    The aims of this workshop were to explain the data model developed for the commercial fisheries Regional Database and Estimation System (RDBES), assist in populating it with real data for the second test data call for the RDBES, and encourage participants to take part in ongoing testing of the RDBES data submission system. This report documents the progress that participants have done to prepare their institutes for future use of the RDBES system. Some issues with data conversion have been identified and are documented in this report. None of the identified issues are thought to be serious impediments to moving forward with the RDBES development according to the roadmap decided by the Steering Committee of the Regional Fisheries Database in 2020. The RDBES Core Group (the group of people developing the RDBES data model) and ICES Data Centre will look at the results of this workshop and either respond to individual questions or adapt the data model and documentation as required. The workshop concluded and reported before the deadline of the test data call. For a complete test of the data model, all participants were encouraged to complete the data call. A report on the degree of completion of the data call may be expected from WGRDBESGOV which convenes after the data call deadline

    Workshop on Raising Data using the RDBES and TAF (WKRDBESRaiseTAF; outputs from 2022 meeting)

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    41 páginasThe Workshop on Raising Data using the RDBES and TAF (WKRDBES-Raise&TAF) met online (26–30 of September 2022) to evaluate the use of the Regional Database and Estimation System (RDBES) format to reproduce the 2022 InterCatch input and output, identifying a Transparent Assessment Framework (TAF) structure to organize the intermediate steps and to propose standardized output formats. The main outcomes of WKRDBES-Raise&TAF were: · RDBES provides sufficient support for current national estimation protocols. However, some minor issues were reported that hampered an exact reproduction of the estimates. Therefore, adaptations of the data model should not be excluded completely. · All the input to stock assessment that InterCatch currently provides, could be reproduced. The participants started from the current stock extracts that can be downloaded from InterCatch. · A workflow was proposed with a national TAF repository for each country, a stock estimation repository and a stock assessment repository. The intermediate output of those repositories will be stored in an ‘intermediate output database’ and depending on the user role, you will get access to the relevant stages in this workflow. · The following requirements for the standard output formats were defined: they cannot be more restrictive than the InterCatch input and output format; they should present measures of uncertainty and sample sizes (for national estimates) and should have a configurable domain definition (for national estimates). Despite those successful outcomes, the current plan for transition to an operational system was concluded to be too optimistic. WKRDBES-Raise&TAF therefore recommends to the Working Group on Governance of the Regional Database and Estimation System (WGRDBESGOV) to revise the roadmap and allow RDBES to be in a test phase also for 2023. WKRDBES-Raise&TAF felt the need to test the proposed workflow on a small scale and therefore recommends to the WGRDBESGOV to arrange a workshop where two stocks (pok.27.3a46 (Saithe (Pollachius virens) in Subareas 4, 6 and Division 3.a (North Sea, Rockall and West of Scotland, Skagerrak and Kattegat) and wit.27.3a47d (Witch (Glyptocephalus cynoglossus) in Subarea 4 and Divisions 3.a and 7.d (North Sea, Skagerrak and Kattegat, eastern English Channel)) will be set up to go through the whole flow.Peer reviewe

    Endobiotic communities of Marine Sponges in Cyprus (Levantine Sea)

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    Sponges host cryptic endobionts within their network of canals, with representatives from all major animal phyla. This study investigates the endobiotic community of four sponge species (Spongia officinalis, Sarcotragus spinosulus, Ircinia cf. variabilis and Ircinia oros) that were collected during scientific trawl surveys in the coastal area of Cyprus. Moreover, it examines the endobiotic community composition of S. spinosulus in relation to sponges' volume, and various environmental variables. In general, the four sponge endobiotic communities were similar; S. officinalis had a significantly different community composition to I. cf. variabilis and I. oros. The phyla identified followed the general infauna composition of sponges, with the relative abundances of the dominant phyla, Arthropoda and Annelida, ranging from 66.9 - 83.7 % and 4.8–26.5 %, respectively. The highest intensity (I) corresponded to the isopod Cymodoce truncata in S. officinalis (I = 85 individuals/sponge) and S. spinosulus (I = 27.2 individuals/sponge). A general linear model also suggested that distance from shore influenced the total endobiotic abundance of S. spinosulus. This is the first sponge endobiotic community baseline study that covers the whole coastal area of the Republic of Cyprus and is particularly important due to potential changes of Eastern Mediterranean endobiotic communities due to the invasion through the Suez Canal of non-indigenous species

    First genetically confirmed records of the little gulper shark Centrophorus uyato (Squaliformes: Centrophoridae) from Cypriot waters

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    The taxonomy within the genus Centrophorus has been controversial almost since its origin, raising uncertainties about the identification, the phylogenetic placement and the geographical distribution of several species. The partial nucleotide sequences of two mitochondrial DNA gene regions, the cytochrome c oxidase subunit I and the 16S ribosomal RNA, genetically confirmed the presence of the little gulper shark in Cypriot waters. The species presence in the Mediterranean Sea is revised and discussed
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