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It is well known that bottom trawling affects the abiotic (seafloor morphology, sediment resuspension, water turbidity) and biotic components (biodiversity, biomass and production) of habitats. However, comparative studies on the effect of trawling on epibenthic communities of sedimentary bottoms are scarce. One of the objectives of LIFE IP INTEMARES project is to assess the impact of bottom trawling on vulnerable benthic habitats of the circalittoral bottoms of the Menorca Channel (western Mediterranean), designated Site of Community Importance (SCI) within the Natura 2000 network. The present study compares the benthic communities of four areas subjected to different bottom trawl fishing intensity levels (null, intermediate and high). The assignment of fishing effort levels was based on the fishing effort distribution in the area calculated from Vessel Monitoring System (VMS) data. The biological samples were collected from 46 beam trawl stations sampled during a scientific survey on April 2019. In order to detect differences related to the different levels of fishing intensity, we calculated four “traditional” diversity indices (i.e. species richness, Margalef’s richness, Pielou’s evenness and Shannon’s diversity), and the recently developed N90 diversity index, which has shown to be useful in the detection of the response of demersal and benthic communities to fishing pressure. Our results show the highest values of all the analyzed indices in the nonimpacted area, suggesting a negative effect of bottom trawling on the benthic communities present in Menorca Channel. However, no clear pattern was observed between different degrees of trawling intensity and diversity values, so other factors such as environmental conditions must be also considered to explain these results.

Based on geophysical (multibeam echosounder and very high resolution parametric profiles) and sedimentological (Shipek dredge) data acquired during the INTEMARESCANAL0419 expedition, different geomorphologic features have been identified. The study area is located in the continental shelf of the Menorca Channel between 37 and 116 m water depth (mwd). Shallower zones are dominated by lense shaped bedforms, up to 1 m high. They are characterized by very low backscatter values. Also small circular -or slightly elongated- mounds are very frequent morphologies occurring up to 100 mwd. Their sizes range from 1 to 5 m high and 20 to 80 m of diameter with high backscatter values. The most prominent morphological features at intermediate depths are a set of channels that dig in the shelf from 60 to 90 mwd. They show vertical walls and extend up to several km. In the parametric profiles, paleochannels filled by a sedimentary layer approximately 30 ms (two-way time) thick can be observed. The deepest zones are characterized by an erosive surface covered by a thin layer of no consolidated sediments. A visual analysis of the samples shows that sediments are characterized by coarse sand and gravel mainly composed of biogenic particles (carbonated fragmented bioclasts). Higher values of backscatter correspond to samples with a variable abundance of rhodoliths whereas lower values correspond to sands. The variety of morphological features can be mainly related to erosive and depositional Quaternary processes in the continental. Benthic communities strongly influence sediment composition, which was found to be characterized by a high carbonate content.

Póster para el 41e Congres de la Commission Internationale pour l’Exploration Scientifique de la Mer Méditerranée (CIESM), celebrado entre el 12 y el 16 de septiembre de 2016 en Kiel.-- 1 page, This study was conducted in the NW Mediterranean where the fishermen associaGon of Roses has closed during two years one of their fishing grounds. We compared the community structure between the closed fishing ground, and an adjacent area where fishing was allowed in order to explore the effects of a closed area on the epibenthic community. Results indicate that density of most representaGve taxonomic groups (i.e. teleost fishes, cnidarians, crustaceans and echinoderms) is significantly higher in the closed zone than in the surrounding fishing area. AddiGonally, mulGdimensional scaling analysis showed two well-defined assemblages corresponding to the samples where fishing was allowed and the closed zone. These results indicate that fishing closure is an appropriate measure to protect the epibenthic community

41e Congres de la Commission Internationale pour l’Exploration Scientifique de la Mer Méditerranée (CIESM), 12-16 September 2016, Kiel.-- 1 page, 2 figures, A hake nursery area has been closed during two years by the Roses fishermen association (NW Mediterranean Sea) in order to protect the recruitment of hake in the area. The aim of this study is to evaluate the effectiveness of this measure. Hake landings displayed marked fluctuations in the last 15 years although effort decreased. First results regarding the measure of closing the hake nursery area indicate that abundance and biomass of recruits were higher in the closed zone than in the surrounding fishing area, suggesting that this measure could contribute to protect significantly the hake recruitment

VI Congreso Ibérico de Ictiología - VI Iberian Congress of Ichthyology (SIBIC2016), celebrado del 21 al 24 de junio de 2016 en Murcia.-- 1 page, The increase in abundance, biomass and diversity within protected areas has been well documented, especially in rocky littoral areas. In this study we assess the effects of a two years fishing ban in a muddy-sandy bottom Roses' fishing ground (NW Mediterranean) located at 130 m depth. This fishing ground was closed by fishermen during 2014-15, in order to protect hake (Merluccius merluccius) recruitment, the main target species of the trawl fleet in Roses. Population density, biomass, size and diversity were compared inside and outside the protected zone to evaluate changes in the fish community. Biological data were collected monthly on board of trawl fishery vessels from March to June 2015. A total of 51 fish species were found inside the protected and 40 outside. From the 13 species found exclusively in the protected area, stands out the presence of vulnerable species as Raja polystigma, suggesting that the closed area could act as a refuge for some species. Results showed significant higher values of density inside (mean value= 15.724 ind/km2) in comparison with outside (6.616 ind/km2) and also biomass (875 kg/km2 inside, 299 kg/km2 outside) for the overall community values, as well as for the most frequent species. The observed differences between areas were more marked in commercial species (i.e. Merluccius merluccius, Lepidotrigla cavillone, Lepidorhombus boscii, Argentina shpyraena and Trachurus trachurus) than in non-commercial ones (i.e. Capros aper and Scyliorhinus canicula). Moreover, both small-sized and large-sized individuals of the most frequent species were found mainly into the protected area. Our results suggest that the management measure adopted by Roses fishermen has positive effects on the demersal community

14th Deep-Sea Biology Symposium (DSBS), 31 August 2015 - 04 September 2015, Aveiro

14th Deep-Sea Biology Symposium (DSBS), 31 August 2015 - 04 September 2015, Aveiro

Presentación para el 2nd International Symposium on Submarine Canyons (INCISE2014), 29th September-1st October 2014, Edinburgh.-- 17 pages

2013 Annual Symposium of the Fisheries Society of the British Isles (FSBI Symposium 2013) Deep Sea Fish Biology, 8-11 July 2013, Glasgow, The description of reproductive strategies and fecundity of fish has an important relevance in the study of their biology and population dynamics. However, our knowledge of the reproductive capacity of deep-sea fish is still very poor. Production of eggs is an energy-demanding process and, thus, a shortfall in food supply may cause a decrease in fecundity and/or egg size. Continental slopes are transitional environments between the shelf and deep basins, with strong gradients in pressure, temperature, food supply and light. Therefore, the study of fecundity and egg size of fish along the continental slope can provide important data to better understand the modulation of reproductive capacity. The fish community of the Catalan margin (northwestern Mediterranean) was sampled between 400 and 2700 m depth. The gonads of 2672 individuals from 13 different species were analyzed macroscopically to determine sex and maturity stage. The mature ovaries of a subsample of 300 individuals were dissected out for histological and image analyses. The oocyte-size distribution patterns show that all species analyzed present group synchronous ovarian organization. Total fecundity and egg size were quantified for the first time for the 13 species considered. The results were compared with previous published data on shallow-water and Atlantic species. Preliminary results showed a pattern of decreased fecundity with depth. Fecundity and egg sizes were lower in Mediterranean species compared to congeneric species in the Atlantic Ocean as reported in the literature. The results are discussed in relation to environmental characteristics

Memoria de tesis doctoral presentada por Ulla Fernández de Arcaya Redondo para optar al grado de Doctora en Ciencias del Mar por la Universitat de Barcelona (UB), realizada bajo la dirección del Dr. Joan Baptista Company Claret, de la Dra. Laura Recasens Albaladejo y de la Dra. Eva Ramirez Llodra del Institut de Ciències del Mar (ICM-CSIC), The present thesis starts from the premise that the knowledge of reproductive strategies of species is a fundamental tool for the understanding of ecological system characteristics (Giangrande et al., 1994). The deep sea (>1000 m depth) is the largest ecosystem on Earth and, although a large effort has been made in its exploration, it is still one of the least known habitats in the planet (Ramirez-Llodra et al., 2010). Our understanding in diversity, distribution and ecology aspects of deep-sea fish populations has increased considerably, however, the reproductive aspects of most of the fishes inhabiting these unique environments is still poorly understood. This lack of information represents a great opportunity to explore and further investigate these important topics to better understand, following a comparative approach, the ecological processes that shape the life-history patterns of deep-water fishes in the Mediterranean Sea. But first, we must have a well knowledge of species specific life strategies. [...], This thesis was conducted at the Institute of Marine Sciences of Barcelona (ICM-CSIC) thanks to PhD grant (BFR 08/067) from the Spanish Ministry of Economy and Competitiveness (FPI Program). The thesis was also conducted in the frame of RECS, PROMETEO and DOS MARES projects to JBC funded by the Spanish Science and Innovation Ministry (refs. REN02/04556/C02/MAR, CTM2007-66316- C02/MAR and CTM2010-21810-C03-03/MAR, respectively) and Hermione project to ERLL founded by the European Commission Seventh Framework Program (grant agreement 226354)

40th CIESM Congress: The largest Forum on Mediterranean and Black Sea Research, 28 October - 1 November 2013, Marseille, France.-- 1 page, 1 figure, The reproductive strategies and fecundity of 13 species of the NW Mediterranean deep-sea fish community (750-2250 m depth) were analyzed. The results were compared with previous published data of shallower-living NW Mediterranean species . The results showed that all species analyzed present group-synchronous ovarian organization. All the species present the general pattern of large eggs and low Total Fecundity (TF) in comparison with shallower distributed fish species. TF is positively correlated with fish length. However, no significant relationship between length and depth was found, suggesting that the environmental factors associated with depth play an important role in determining fecundity

RESUMEN.- Del 24 de Octubre al 18 de Diciembre de 2007, se han realizado 67 pescas experimentales de arrastre de fondo, a bordo de las embarcaciones B/P Berto y B/P Sort de Taranet, en caladeros del talud del Golfo de León, situados en aguas internacionales al este del Cabo Creus y alejados entre 70 y 100 millas de su puerto base (Port de la Selva). Ambos barcos trabajaron de manera continuada durante 46 horas semanales (su período de actividad habitual es de 5 días semanales y 12 ó 16 horas diarias), utilizando una red de arrastre tipo cuadrado-dragón, que habitualmente usan para sus operaciones de pesca comercial en el área. De manera simultánea, un barco utilizó el copo tradicional de malla rómbica de 40 mm, mientras que el otro utilizó un copo de malla cuadrada de 40 mm. Ello permitió comparar la selectividad de ambos copos por el método de pescas paralelas. Del total de pescas, 50 fueron consideradas válidas para el análisis de datos, en base a dos estratos batimétricos: (i) 300-450 m, dirigidas a cigala (B/P Berto: 14 pescas entre 357 y 434 m; B/P Sort de Taranet: 14 pescas entre 371 y 451 m); (ii) 450-700 m, dirigidas a gamba roja (B/P Berto: 11 pescas entre 478 y 692 m; B/P Sort de Taranet: 11 pescas entre 493 y 571 m). Se han estimado los rendimientos medios, estandarizados a hora de arrastre efectivo, su fracción comercial y descartada y la distribución de tallas de las principales especies de interés comercial y ecológico. Paralelamente, se ha recogido información de los desembarcos y consumo de combustible esta acción piloto y para el mismo período de 2006, en que estas embarcaciones realizaron su actividad pesquera rutinaria. El análisis de esta información se ha realizado mediante técnicas uni- y multi-variantes. Los elevados rendimientos, así como la distribución de tallas de la captura de las principales especies explotadas, indican que los fondos prospectados están poco explotados. En ambos estratos batimétricos, con la malla cuadrada se redujeron los descartes, sin una disminución significativa de los rendimientos comerciales. Del mismo modo, la estrategia de pesca aplicada durante la acción piloto redujo el esfuerzo efectivo de pesca, sin disminuir el rendimiento de la pesquería respecto del mismo período de 2006. Además, se redujo considerablemente el consumo de combustible, lo que repercutió positivamente en las tasas de combustible consumido por unidad de desembarcos. La estrategia de explotación aplicada en la acción piloto mejora la relación coste-eficiencia de la pesquería y presenta una serie de ventajas, tanto de mejora en el rendimiento pesquero y en la explotación de los recursos, como de carácter medioambiental y social. No obstante, aplicar esta estrategia a la explotación comercial conlleva riesgos para el mantenimiento de los stocks de especies explotadas y la conservación de hábitats de especial interés y ecosistemas marinos vulnerables, en un área con numerosos cañones submarinos, como el Golfo de León., RESUM.- INFORME DEL SEGUIMENT CIENTÍFIC DE L’ACCIÓ PILOT RAI/AP-26/2007: PESCA EXPERIMENTAL AMB ART DE RÒSSEC DE FONS EN EL GOLF DE LLEÓ (MEDITERRÀNIA NOR-OCCIDENTAL): Del 24 de Octubre al 18 de Desembre de 2007, s’han dut a terme 67 pesques experimentals de ròssec de fons, a bord de les embarcacions B/P Berto i B/P Sort de Taranet, en caladors del talús del Golf de Lleó, situats en aigües internacionals a l’est del Cap de Creus, allunyats entre 70 i 100 milles del seu port base (Port de la Selva). Ambdós vaixells van treballar de manera continuada durant 46 hores setmanals (el seu període d’activitat habitual és de 5 dies setmanals i 12 ó 16 hores diàries), utilitzant una xarxa de ròssec de tipus quadratdragó, que habitualment utilitzen per les operacions de pesca comercial a l’àrea. De manera simultània, un vaixell va emprar el cóp tradicional de malla ròmbica de 40 mm, mentre que l’altre va emprar un cóp de malla quadrada de 40 mm. Això va permetre comparar la selectivitat d’ambdós cóps, mitjançant el mètode de pesques paral·leles. Del total de pesques, 50 foren considerades vàlides per l’anàlisi de dades, en base a dos estrats batimètrics: (i) 300-450 m, dirigides a escamerlà (B/P Berto: 14 pesques entre 357 i 434 m; B/P Sort de Taranet: 14 pesques entre 371 i 451 m); (ii) 450-700 m, dirigides a gamba vermella (B/P Berto: 11 pesques entre 478 i 692 m; B/P Sort de Taranet: 11 pesques entre 493 i 571 m). S’han estimat els rendiments mitjans, estandarditzats a hora efectiva de ròssec, la seva fracció comercial i rebutjada i la distribució de talles de les principals espècies d’interès comercial i ecològic. Paral·lelament, s’ha recollit informació dels desembarcaments i consum de combustible durant l’acció pilot de 2007 i pel mateix període de 2006, en que aquestes embarcacions van realitzar la seva activitat pesquera rutinària. L’anàlisi d’aquesta informació s’ha realitzat mitjançant tècniques uni- i multi-variants. Els elevats rendiments, així com la distribució de talles de la captura de les principals espècies explotades, indiquen que els fons prospectats estan poc explotats. En ambdós estrats batimètrics, amb la malla quadrada es van reduir els rebuigs, sense una disminució significativa dels rendiments comercials. De manera semblant, l’estratègia de pesca aplicada durant l’acció pilot va reduir l’esforç efectiu de pesca, sense disminuir el rendiment de la pesquera respecte del mateix període de 2006. A més, es va reduir considerablement el consum de combustible, la qual cosa va repercutir positivament en les tases de combustible consumit per unitat de desembarcaments. L’estratègia d’explotació aplicada en l’acció pilot incrementa la relació cost-eficiència de la pesquera i presenta una sèrie d’avantatges, tant de millora en el rendiment pesquer i en l’explotació dels recursos, com de caràcter mediambiental i social. No obstant, aplicar aquesta estratègia a l’explotació comercial comporta riscs pel manteniment dels estocs d’espècies explotades i la conservació d’hàbitats d’especial interès i ecosistemes marins vulnerables, a una àrea amb nombrosos canons submarins, com el Golf de Lleó., Secretaria General de Pesca Marítima

12 pages, 13 figures, The continental margin of the Catalonia is crossed by several submarine canyons of different evolutionary history (Fig. 1) (Canals et al., 2004a). The main characteristic of the circulation pattern on the Catalan coast is a slope current referred to as the Northern current, which is associated with a shelf–slope density front that in this area flows mainly towards the southwest (Font et al., 1988). This baroclinic current separates the low-salinity shelf waters from the denser open-sea saline waters

12th International Deep-Sea Biology Symposium, 7-11 June 2010, Reykjavík, Iceland, The present study is an analysis of seasonal and depth-related trends in abundance, biomass, body size and reproductive strategies of four grenadier species Coelorinchus mediterraneus, Coryphaenoides guentheri, Nezumia aequalis, and Trachyrinchus scabrus of the deep western Mediterranean. The specimens were obtained using an OTMS bottom trawl along a seasonal period (autumn 2008 - autumn 2009), inside and outside the Blanes Canyon (Catalan Sea) at depths between 900 m and 2000 m. These species present a different depth range distribution: Nezumia aequalis and Trachyrinchus scabrus show its maximum in abundance and biomass at upper slope (900–1050 m), Coelorinchus mediterraneus at middle slope (1200–1500 m) and Coryphaenoides guentheri at lower slope (1500–2000 m). Size trends varied depending on the species. Females grow larger than males and, except for Coelorinchus mediterraneus, females outnumbered males. The Mediterranean Sea is a physically fairly constant and oligotrophic environment. Hence, we might expect a consistent pattern of reproduction of all the above-mentioned species. In contrast, the macroscopic and microscopic analyses of the gonads exhibit different reproductive strategies within the macrourid family, which vary between continuous (Nezumia aequalis), quasi-continuous (Coelorinchus mediterraneus) and seasonal (Trachyrinchus scabrus and Coryphaenoides guentheri) reproductive cycle. The adoption of different reproductive strategies is probably related to avoid competence between these species for the same trophic resources. Moreover, our results indicate that the main reproductive period is from autumn to winter, coinciding with the formation of mixed layers in the Mediterranean Sea. This further corroborates the hypothesis that reproductive periods in deep-sea fish have adapted to fluxes of organic matter from the photic zone. Further analyses of additional species belong to the same deep-sea community (e.g. Moridae and Notacanthidae) and the characterization of the environmental conditions will help us in finding the existence of a general demographic and reproductive pattern and identifying the underlying environmental factors

Trabajo final presentado por Elena Fagín García para el Máster en Oceanografía y Gestión del Medio Marino de la Universitat de Barcelona (UB), realizado bajo la dirección de la Dra. Ulla Fernández-Arcaya y la Dra. Laura Recasens del Institut de Ciències del Mar (ICM-CSIC).-- 29 pages, 12 figures, 5 tables, Protection zones provide an effective tool for fisheries management and biodiversity conservation. In fact, an increase in abundance, biomass and diversity within protected areas have been well documented. In this study we assess the no fishing effects in a Roses` fishing ground which was closed by fishermen in 2014, in order to protect the Merluccius merluccius recruitment. We conducted a comparative approach between inside and outside protected zone to evaluate changes in population density, biomass and diversity of the whole fish community. The size frequency distribution between inside and outside area was also studied to evaluate changes in population size structure for the most abundant species. In addition, for the target species, Merluccius merluccius, the sex ratio and the hepatosomatic index was analysed in both areas. The biological data were collectedmonthly on board trawl fishery vessels, inside and outside the protected area. Results indicate significant increases in all the studied parameters inside the protected area, mainly in biomass. Furthermore, the recruitment of the 6 most abundant species (observed as small-sizes individuals), including hake recruits, was found into the protected area. Also, large-sized individuals of these species were more frequent in this protected area. Our results suggest that the management measured adopted by Roses fishermen have a positive effects in the density, biomass and diversity of fish community, thus aiding recovery of fish stock. However, longer temporally sampling of fishery catches inside and outside the closure area is required in order to confirm the observed positivetrends

Trabajo final presentado por María Peiró Expósito para el Master en Oceanografía de la Universidad de Las Palmas de Gran Canaria (ULPGC), realizado bajo la dirección del Dr. Joan Baptista Company Claret y de la Dra. Ulla Fernández Arcaya del Institut de Ciències del Mar (ICM-CSIC)

Trabajo presentado por Manolis Metaxakis para la obtención del Grado realizado bajo la dirección del Dr. Joan B. Company y la Dra. Ulla Fernandez-Arcaya del Institut de Ciències del Mar (ICM-CSIC)

Trabajo final presentado por Clara Cerviño para el Master en Ciencias del Mar de la Universitat de Barcelona (UB), realizado bajo la dirección de Joan Baptista Company Claret, Laura Recasens Albaladejo y Ulla Carolina Fernandez de Arcaya Redondo del Institut de Ciències del Mar (ICM-CSIC)