Suchergebnisse

The time series of elasmobranch catch rates off the Tuscany coasts (NW Mediterranean) were investigated by means of min/max auto-correlation factor analysis in order to estimate variations in population abundance and evaluate the influence of environmental and anthropogenic factors. The analyses highlighted a general decreasing trend in the catch rates of sharks and skates from 1961 to the mid-1990s, mainly influenced by the increase in fishing effort. Since the 1990s, the EU Common Fishery Policy for the Mediterranean has promoted the reduction of fishing fleets through incentives to vessel demolition. The Porto S. Stefano trawl fleet has decreased by about 50%, leading to a decrease in fishing effort which seemed to be the most relevant factor affecting the increasing trend shown by the catch rates of Galeus melastomus, Scyliorhinus canicula and skates from 1991 to 2009. The elasmobranch assemblage did not undergo major shifts but the weighted frequency of occurrence shows that elasmobranchs were more frequent in the past. Particular caution should be paid in interpreting the recent rebound of some species as an early sign of recovery: trawl survey data and landing data show that over the last 50 years elasmobranch fauna have undergone a drastic decline and that recent rebounds are still far from a recovery to historical levels. ; Se investigaron las series históricas de datos de captura de algunas especies de Elasmobranquios en los mares de Toscana (Mediterráneo noroccidental), por medio del análisis de auto-correlación factorial MAFA, con el fin de evaluar las variaciones en la abundancia de poblaciones y la influencia de factores ambientales y antropogénicos. Los análisis permitieron poner en relieve una tendencia a la disminución, a partir de 1961 hasta la mitad de los años 1990, de las tasas de captura de las especies de tiburones y rayas demersales. Esta disminución parece ser debida principalmente al aumento del esfuerzo pesquero. Sin embargo, desde 1990 capacidad y actividad pesquera mostraron una tendencia a la disminución, como resultado de la Política Pesquera Común de la UE para el Mediterráneo. La flota de arrastre de Porto Santo Stefano disminuyó en un 50%; esta reducción parece ser el factor más importante que produjo un aumento en los indices de abundancia relativa de Galeus melastomus, Scyliorhinus canicula y de las rayas, desde 1991 a 2009. Sin embargo la composición en especies de los Elasmobranquios no ha mostrado evidentes cambios en el tiempo, a pesar de muchas especies que han sufrido una disminución en la frecuencia de occurrencia. Por lo tanto, la interpretación de estos resultados como señal de recuperación de las poblaciones de elasmobranquios, necesita de una precaución especial. De hecho durante los últimos 50 años la fauna de elasmobranquios en el Mediterráneo ha sufrido una drástica reducción y todavía no se está observando ninguna considerable señal de recuperación.

There is currently very little information on the survival of discards of unwanted and unregulated catches of invertebrates after the stresses caused by capture. A great number of the unregulated invertebrate species form the basis of essential fish habitats for important fisheries resources such as hake, red mullet and cuttlefish. Thus, data on their survival after discarding may help to interpret the role of these species within the benthic ecosystems. Furthermore, descriptor 6 of the Marine Strategy Framework Directive (EU Directive 2008/56/E) foresees maintaining sea floor integrity at a level that ensures that the structure and functions of the ecosystems are safeguarded, and Article 7(d) of the Common Fisheries Policy (EU Reg. 1380/2013) foresees the implementation of management measures for fishing with low impact on the marine ecosystem and fishery resources. Survival measurements by direct recovery of tagged discarded species are not effective in bottom trawl fisheries, for which alternative studies such as semi-quantitative measures obtained on board prior to discarding can be considered as appropriate for mortality estimation. The present work assessed the survival of unwanted species using a semi-quantitative assessment on the deck of trawlers and at the laboratory for a period of 96 hours in two Mediterranean areas (the Catalan coast and the Ligurian and Northern Tyrrhenian seas). A high number of discarded invertebrates showed a high percentage of survival (>70%) in both assessments. The results can be used to provide information that can help to achieve higher survival levels of discarded specimens and enhance the productivity of fishing grounds by increasing the health of benthic ecosystems. ; Actualmente, hay muy poca información sobre la supervivencia del descarte de los invertebrados no-deseados y no-regulados después del stress de la captura. Un gran número de especies de estos invertebrados son básicas para los hábitats esenciales de importantes recursos pesqueros como la merluza, el salmonete o la sepia. Por lo tanto, información sobre su supervivencia al ser descartados pueden ayudar a interpretar el papel de estas especies dentro de los ecosistemas bentónicos. Además, el punto 6 de la Directiva Marco de Estrategia Marina (MSFD, EU Directive 2008/56/E) prevé mantener la integridad del fondo marino a un nivel que garantice la protección de la estructura y de las funciones de los ecosistemas, y el artículo 7 (d) de la Política Pesquera Común (PPC EU Reg. 1380/2013) prevé la implementación de medidas de gestión para la pesca, que tengan bajo impacto tanto en el ecosistema marino como en los recursos pesqueros. En el caso de las pescas de arrastre de fondo, no es efectiva la estimación de la supervivencia a partir del método directo de captura-recapture de las especies del descarte marcadas, por lo que los estudios alternativos, como las medidas semicuantitativas obtenidas a bordo antes del descarte, pueden considerarse una estimación de la mortalidad apropiada. El presente trabajo evaluó la supervivencia del descarte de especies no-deseadas utilizando una Evaluación Semicuantitativa (SQA) mediante dos estudios: uno sobre la cubierta de los arrastreros y el otro en laboratorio durante un período de 96 horas, en dos áreas del Mediterráneo, las costas Catalanas y en los mares de Liguria y del Tirreno Norte. Los resultados mostraron en ambos estudios, que un alto número de invertebrados descartados tenía un alto porcentaje de supervivencia (>70%). El propósito de estos resultados es proporcionar información que puede ayudar a alcanzar niveles de supervivencia más altos de los individuos descartados. Al mismo tiempo, se espera que con esta mejora se consiga potenciar la productividad de los caladeros al aumentar la salud de los ecosistemas bentónicos.

Special issue on Discards regulation vs Mediterranean fisheries sustainability.-- 10 pages, 5 figures, 5 tables, supplementary material http://scimar.icm.csic.es/scimar/supplm/sm04784esm.pdf ; [EN] There is currently very little information on the survival to discarding of unwanted and non-regulated catches of invertebrates, after the stresses due to capture. A great number of the non-regulated invertebrate species are the basis of Essential Fish Habitats for important fisheries resources such as hake, red mullet or cuttlefish. Thus, data on their survival to discarding may help to interpret the role of these species within the benthic ecosystems. Furthermore, descriptor 6 of Marine Strategy Framework Directive (MSFD, EU Directive 2008/56/E) foresees maintaining sea floor integrity at a level that ensures that the structure and functions of the ecosystems are safeguarded and article 7(d) of the Common Fishery Policy (CFP, EU Reg. 1380/2013) foresees the implementation of management measures for fishing with low impact on the marine ecosystem and fishery resources. Survival measurements by direct recovering tagged discarded species are not effective in bottom trawl fisheries for which alternative studies, such as semi-quantitative measures obtained on board prior to discarding, can be considered as appropriate for mortality estimation. The present work assessed the survival of unwanted species using a Semi-Quantitative Assessment (SQA) on deck of trawlers and at the laboratory for a period of 96 hours in two Mediterranean areas (Catalan Coasts and Ligurian and Northern Tyrrhenian Sea). The results showed that a high number of discarded invertebrates had a high percentage of survival (>70%) in both assessments. The purpose of these results is to provide information that can help to achieve higher survival levels of the discarded specimens. At the same time, it is expected that this improvement can enhance the productivity of the fishing grounds by increasing the health of the benthic ecosystems ; [ES] Actualmente, hay muy poca información sobre la supervivencia del descarte de los invertebrados no-deseados y no-regulados después del stress de la captura. Un gran número de especies de estos invertebrados son básicas para los hábitats esenciales de importantes recursos pesqueros como la merluza, el salmonete o la sepia. Por lo tanto, información sobre su supervivencia al ser descartados pueden ayudar a interpretar el papel de estas especies dentro de los ecosistemas bentónicos. Además, el punto 6 de la Directiva Marco de Estrategia Marina (MSFD, EU Directive 2008/56/E) prevé mantener la inte-gridad del fondo marino a un nivel que garantice la protección de la estructura y de las funciones de los ecosistemas, y el artículo 7 (d) de la Política Pesquera Común (PPC EU Reg. 1380/2013) prevé la implementación de medidas de gestión para la pesca, que tengan bajo impacto tanto en el ecosistema marino como en los recursos pesqueros. En el caso de las pescas de arrastre de fondo, no es efectiva la estimación de la supervivencia a partir del método directo de captura-recapture de las especies del descarte marcadas, por lo que los estudios alternativos, como las medidas semicuantitativas obtenidas a bordo antes del descarte, pueden considerarse una estimación de la mortalidad apropiada. El presente trabajo evaluó la supervivencia del descarte de especies no-deseadas utilizando una Evaluación Semicuantitativa (SQA) mediante dos estudios: uno sobre la cubierta de los arrastreros y el otro en laboratorio durante un período de 96 horas, en dos áreas del Mediterráneo, las costas Catalanas y en los mares de Liguria y del Tirreno Norte. Los resultados mostraron en ambos estudios, que un alto número de invertebrados descartados tenía un alto porcentaje de supervivencia (>70%). El propósito de estos resultados es proporcionar información que puede ayudar a alcanzar niveles de supervivencia más altos de los individuos descartados. Al mismo tiempo, se espera que con esta mejora se consiga potenciar la productividad de los caladeros al aumentar la salud de los ecosistemas bentónicos ; This study received funding from the European Commission's Horizon 2020 Research and Innovation Programme under Grant Agreement No. 634495 for the project "Science, Technology, and Society Initiative to Minimize Unwanted Catches in European Fisheries" (MINOUW) ; Peer Reviewed

Since the first introduction of the landing obligation (a.k.a. Discard ban) in 2015, the EU Mediterranean fisheries are facing some unforeseen challenges. The demersal bottom trawl fisheries, being the most significant contributors to the so-called 'discard problem', are confronted with the greatest challenges. Data from the Italian and the Greek fleet, spanning over two decades (1995–2015), were analysed with the intention of revealing the diversity and heterogeneity of the discard problem, especially for regulated species. Species composition of discards, as well as discarding rates, were shown to be irregular, fluctuating among areas, depth strata, seasons and years. Although fish dominated the discarded gross catch in weight, benthic invertebrates (other than commercial cephalopods and crustaceans) were the taxa discarded almost exclusively. The established minimum conservation reference size was largely ignored by fishers. From a management point of view, the present investigation suggests that the recently established Discard Management Plans lack scientific evidence (given the high intrinsic variability of the parameters and confusion regarding the rules) and provide exemptions from the landing obligation that will in practice allow the average Mediterranean bottom trawl vessel to continue business as usual. Moreover, detecting if these rules are actually respected is an almost impossible task for the Mediterranean control and enforcement authorities. Incentivizing the adoption of fishing technologies and practices that reduce pre-harvest mortality and post-harvest discards, while avoiding damage to sensitive marine species and habitats, seems the only way to move forward, rather than dealing with the problem after it has occurred.

Since the first introduction of the landing obligation (a.k.a. Discard ban) in 2015, the EU Mediterranean fisheries are facing some unforeseen challenges. The demersal bottom trawl fisheries, being the most significant contributors to the so-called 'discard problem', are confronted with the greatest challenges. Data from the Italian and the Greek fleet, spanning over two decades (1995–2015), were analysed with the intention of revealing the diversity and heterogeneity of the discard problem, especially for regulated species. Species composition of discards, as well as discarding rates, were shown to be irregular, fluctuating among areas, depth strata, seasons and years. Although fish dominated the discarded gross catch in weight, benthic invertebrates (other than commercial cephalopods and crustaceans) were the taxa discarded almost exclusively. The established minimum conservation reference size was largely ignored by fishers. From a management point of view, the present investigation suggests that the recently established Discard Management Plans lack scientific evidence (given the high intrinsic variability of the parameters and confusion regarding the rules) and provide exemptions from the landing obligation that will in practice allow the average Mediterranean bottom trawl vessel to continue business as usual. Moreover, detecting if these rules are actually respected is an almost impossible task for the Mediterranean control and enforcement authorities. Incentivizing the adoption of fishing technologies and practices that reduce pre-harvest mortality and post-harvest discards, while avoiding damage to sensitive marine species and habitats, seems the only way to move forward, rather than dealing with the problem after it has occurred.

Commission Decision of 25 February 2016 setting up a Scientific, Technical and Economic Committee for Fisheries, C(2016) 1084, OJ C 74, 26.2.2016, p. 4–10. The Commission may consult the group on any matter relating to marine and fisheries biology, fishing gear technology, fisheries economics, fisheries governance, ecosystem effects of fisheries, aquaculture or similar disciplines. This report, on methods for supporting stock assessment in the Mediterranean (STECF-21-02), addresses the data checking and preparation for stock assessment once the data has been submitted following the annual data calls. The report provides an overview of the data errors and quality control carried out on both commercial landings data and MEDITS survey data. The analyses reported also address the small fraction of commercial catch with sampling gaps, and how these are assigned appropriate length frequency distributions. The results of these check and assignments are provided by species, GSA and country. Quality checks were carried out on Medits data check consistency of the main reporting files and highlighting where data inconsistencies occurred. Additionally the total landings reported to the European Commission under the Black & Med-Sea data call, the Fisheries Independent Data call and the Annual Economic Report data call were compared at species aggregated to GSA. Some important differences were observed and these are reported. In addition the EWG reviewed a technical report on the sampling of commercial catch in the Greek Fisheries, the review and some suggested further work are included in this report. ; European Union, Joint Research Centre ; Published ; Refereed