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A number of marine mammal populations is currently threatened by their interactions with fisheries. The present study aimed to provide insights into the severity of potential impacts of operational and biological interactions between top predators and fisheries, in the Bay of Biscay region. Our approach was to modify an Ecopath with Ecosim (EwE) model describing the overall structure and function of the ecosystem by including landings and discards of exploited stocks and estimations of the bycatch of non-target compartments. Second, a set of ecological indices and a trophic level (TL)-based model (EcoTroph, ET) were derived from the EwE model. ET was used to simulate the effects of increasing fishing pressure on the ecosystem and, more particularly, on top predators. The Bay of Biscay was demonstrated to be not far from overexploitation at the current fishing rate, this phenomenon being particularly noticeable for the highest TLs. Within the toothed cetacean community, bottlenose dolphins appeared the most sensitive to resource depletion, whereas common dolphins and harbour porpoises were most impacted by their incidental captures in fishing gears. This study provides a methodological framework to assess the impacts of fisheries on ecosystems for which EwE, or other ecosystem models, already exist.

In the NE Atlantic, evidence has been found of genetic discontinuities between Iberian bottlenose dolphins and those of Scotland and the Mediterranean. Here, we explored the genetic relationships between resident populations of dolphins from southern Galicia (NW Spain) and the Sado estuary (S Portugal), and their relationship with dolphins inhabiting neighbouring areas. A total of 91 skin and muscle samples were taken from stranded and biopsied animals between 1994 and 2008 in southern Galicia (N = 29), the Sado estuary (N = 5) and five other geographical locations (N = 57) including sites around the Iberian Peninsula, the Canary Islands and the Azores. Individuals were genotyped at 10 microsatellite loci and sequenced at the highly variable mitochondrial control region. From individual-based analyses of microsatellite data, dolphins from southern Galicia and the Sado estuary were assigned to an individual genetic population, though nine dolphins were identified as possible migrants between putative populations as their genetic makeup did not correspond with their geographical stranding location. Pairwise estimates of genetic differentiation (F ST) based on mitochondrial and nuclear DNA also revealed genetic differences between populations. The existence of fine-scale population substructure should be considered in the future designation of Special Areas of Conservation (SACs) for the species, as required by the European Habitats Directive.

It has been widely acknowledged that fishery discard practices constitute a purposeless waste of valuable living resources, which plays an important role in the depletion of marine populations. Furthermore, discarding may have a number of adverse ecological impacts in marine ecosystems, provoking changes in the overall structure of trophic webs and habitats, which in turn could pose risks for the sustainability of current fisheries. The present review aims to describe the current state-of-the-art in discards research, with particular emphasis on the needs and challenges associated with the implementation of the Ecosystem Approach to Fisheries Management (EAFM) in European waters. We briefly review the international and European policy contexts of discarding, how discard data are collected and incorporated into stock assessments, selectivity in fishing and the main consequences of discarding for ecosystem dynamics. We then review implementation issues related to reducing discards under the EAFM and the associated scientific challenges, and conclude with some comments on lessons learned and future directions.

The Iberian sardine ( Sardine pilchardus ) is a good example of the typical life strategy of small pelagic fish species around the world: short life span, fast growth and long spawning season, which in the case of the Iberian stock presents two peaks (in winter and spring). This life strategy makes new year classes ve ry dependent on the right environmental conditions to survive the early life stages. Egg and larval survival relies on the right oceanographic mechanisms, to ensure retention in favourable areas, and availability of food. Dispersal of eggs and larvae serio usly reduces their survival and decreases the chances of a good new year class. Because of this dependency on environmental conditions in early life, there is no relationship between the stock size (measured as SSB) and recruitment. Previous studies have e xplored the relationship between environmental variables, at large and local spatial scales, and sardine recruitment in the Galician and Portuguese sardine fishery but have faced two main analytical challenges: short time series and autocorrelated data. We carry out new analysis using statistical methods designed to cope with these challenges, including Dynamic factor Analysis and mixed modelling, to identify and characterise relationships between sardine populations (recruitment, spawning stock biomass, an d (to extend the time series) fishery landings in the area) and a series of global, regional and local environmental variables.

El Instituto Español de Oceanografía inició sus campañas acústicas de primavera para evaluar los recursos pesqueros en la plataforma norte y nordeste de la Península Ibérica en 1986. La serie anual de campañas ha sufrido variaciones metodológicas a lo largo de los años y un cambio en su enfoque. Durante los primeros años de la serie (hasta el 1996) el objetivo principal de las campañas (SARACUS, PELACUS) fue la determinación de la abundancia y distribución del stock de sardina que se realizaba mediante prospección acústica combinada con la información proveniente de arrastres pelágicos. El objetivo principal de los cambios que se han producido en la campaña en los últimos años ha sido el permitir su evolución hacia una plataforma de seguimiento del ecosistema pelágico de la plataforma norte y noroeste peninsular. Con esta evolución, se intenta dar respuesta a la necesidad planteada por la UE y otros organismos internacionales de obtener los datos e información necesarios para alimentar los modelos de ecosistema, concebidos como parte clave del Ecosystem Approach to Fisheries Management (EAFM) y posibilitar la monitorización integrada que pueda dar respuesta a los requerimientos de la Directiva Marco de la Estrategia Marina (2008/56/CE).PELACUS 0411 es la vigésimo octava campaña de la serie histórica cuya extensión permite el llevar a cabo estudios retrospectivos sobre las posibles causas de la variabilidad temporal en las propiedades físicas y biológicas y en los procesos observados en el ecosistema pelágico. Al mismo tiempo, constituye una fuente de datos importante para la calibración y validación de los modelos físicos, acoplados (físico-biológicos) y de hábitat y la recopilación de información necesaria para el cálculo de indicadores que permitan determinar el Buen Estado Medioambiental (GES en inglés) de las aguas de la plataforma del norte y noreste de la Península Ibérica dentro de los requerimientos de la Estrategia Marina. Las campañas PELACUS se engloban e

Depredation, i.e. the damage or removal, of Patagonian toothfish (Dissostichus eleginoides) from longlines by sperm whales (Physeter macrocephalus) can cause considerable economic loss for Spanish fishing vessels in the Southwest Atlantic. The fishery also suffers high bycatch rates of seabirds. The main goal of the study was to assess the extent of depredation and seabird bycatch and to test the potential of the so-called “umbrella” system, coupled with attached stones for faster sinking, for minimizing both. Moreover, we investigated the relationships between sightings of sperm whales, depredation, catches, and environmental variables using generalized additive modelling. Data were collected during 297 hauls on a longliner in 2007/2008 in international waters of the Southwest Atlantic. Sperm whales were sighted during 35% of the hauls, always during gear retrieval, and their presence was positively related to fish damage. The overall depredation rate (0.44% of the total catch) was low, but is assumed to be underestimated because sperm whales were suspected of also taking fish without leaving visual evidence. The “umbrella-and-stones” system was highly effective in preventing bycatch and appeared to restrict depredation, but significantly reduced the catches. The results demonstrate that there is still some way to go to solve the problem of depredation.

The abundance of fin whales (Balaenoptera physalus), sei whales (B. borealis) and minke whales (B. acutorostrata) was estimated from data collected during shipboard sightings surveys conducted as part of CODA and TNASS (Faroese block) in July 2007 in offshore waters of the European Atlantic west of the UK, Ireland, France and Spain, combined with data collected from shipboard and aerial surveys of European Atlantic continental shelf waters conducted as part of SCANS-II in July 2005. Double platform methods employing the trial-configuration method (BT-method) were used in all shipboard surveys. Analysis used Mark-Recapture Distance Sampling to account for animals missed on the transect line. Density surface modelling was undertaken to generate model-based abundance estimates and maps of predicted density. Estimates are presented for the SCANS-II and CODA survey areas. Estimates for the Faroese block of TNASS have been presented elsewhere. The abundance of fin whales in the CODA and SCANS-II areas was estimated as 19,354 (CV 0.24) for identified sightings and 29,512 (CV 0.26) when adjusted to include a proportion of unidentified large whale abundance (which included large baleen and sperm whales), prorated by number of sightings, because there were a large number of such sightings in one of the CODA survey blocks. The model-based estimate of identified fin whales was 19,751 (CV 0.17), more precise than the design-based estimate. Fin whales were mainly found in the southern part of the CODA survey area. Estimates based on identified sightings were comparable to those from the Spanish survey conducted as part of 1989 NASS but were larger if adjusted for a proportion of unidentified large whales. Sei whales were rare except in the southwest of the survey area; the estimate of abundance was 619 (CV 0.34) for identified sightings and 765 (CV 0.43) adjusted for a proportion of unidentified large whales. Minke whale abundance was estimated for shelf and offshore European Atl

Stomach contents were collected from 27 monk seal carcasses between 1997 and 2008 from different areas along the Greek coast. This sample included nine animals that had been deliberately killed and five accidental deaths due to fisheries interactions. Stomachs from monk seals of both sexes, including adults and subadults, were analysed. A total of 530 prey items from at least 71 prey species was identified, with approximately 74% of prey identified at least to genus, while 2.8% could be identified only to class level (i.e., fish or cephalopods). We found 266 cephalopods (50%), 253 fish (48%), a few non-cephalopod molluscs (1.5%), and two crustaceans (0.4%). Faecal samples were also collected but contained no identifiable prey remains. Octopuses were the most important prey in terms of numbers eaten and contribution to reconstructed prey biomass. The common octopus (Octopus vulgaris) (33.9% of prey by number) was around three times as numerous in the diet as the lesser octopus (Eledone cirrhosa) (11.1%). Fish of the families Sparidae (28.1%) and, to a lesser extent, Scorpaenidae (2.3%), Congridae (2.5%), and Atherinidae (2.5%) were also frequent in the stomachs. Many of the prey species recorded are of commercial fishery importance. Exploratory multivariate analysis (redundancy analysis [RDA]) indicated weakly significant seasonal, spatial, and interannual variation in diet and also suggested a relationship between diet composition and cause of death. No trends in diet related to sex or age class were identified. Sparids occurred more frequently in animals that had been deliberately killed than those that had died due to other causes, highlighting the interactions taking place between monk seals and fishing activities.

Resumen Las condiciones hidrográficas observadas durante la campaña Pelacus0411, realizada entre el 26 de marzo y 20 de Abril de 2011 en aguas de la plataforma continental Nord Ibérica, son las propias de comienzos de primavera, caracterizadas por una incipiente estratificación térmica y la presencia de agua de baja salinidad cerca de la costa, principalmente en las proximidades de las desembocaduras de los principales ríos. La fluorescencia (variable indicadora de la abundancia de fitoplancton –producción primaria) presentó los valores más elevados en superficie sobre el talud continental en la zona de Galicia, influenciada por la masa de agua de alta salinidad asociada a la contracorriente de talud (‘Corriente Ibérica hacia el Polo’). A partir del Cantábrico Central, frente a la costa Asturiana, y hacia la zona interna del Golfo de Vizcaya, se observó un máximo sub-superficial de clorofila entorno a los 20 o 30 m. La biomasa total de sardina en la zona de estudio estimada mediante métodos acústicos fue de 11.768 toneladas (t) (151106 individuos). Esta especie se localizó preferentemente en la plataforma de Asturias (sub-área ICES VIIIcE-w), en contraste con su práctica ausencia en aguas de la plataforma de Gallicia (sub-áreas ICES IXa-N y VIIIcW). Los individuos más jóvenes, de edades entre 1 y 2 años, predominaron en Galicia (sub-área ICES IXaN), mientras que los de mayor edad, 3 años, fueron más abundantes en la plataforma de Asturias y del País Vasco (sub-áreas ICES VIIIcE-w y VIIIcE-e respectivamente). Las estimas de abundancia de sardina en la campaña de 2011 son las más bajas de la serie desde 2001 y suponen un motivo de preocupación en relación al estado del stock. Si no tiene lugar un reclutamiento importante, el último de los cuales tuvo lugar en 2004, la previsión apunta hacia un descenso continuado de la biomasa de sardina en la plataforma Nord Ibérica. La biomasa estimada de anchoa fue de 2071 t, correspondiente a 142000 individuos. Éstos se localizaro

Over the past two decades, cephalopod molluscs have attracted increased attention from marine biologists and fishery scientists. Several species are important for European fisheries, as targets of small‐scale coastal fisheries and/or as bycatch in multispecies fisheries for demersal fish. The present report draws on a series of reviews prepared in 2005 for the CEPHSTOCK project (see Section 1). The taxonomy of the main resource species is reviewed (Section 2), and brief descriptions of each species are provided, along with information from studies of population genetics, habitat requirements of paralarvae and adults, and health and ecotoxicology (Section 3). The main fisheries are described, including illustration of gears used in specialized small‐scale fisheries and a discussion of the socio-economic importance of the fisheries. The current status of cephalopod aquaculture is reviewed, highlighting notable advances in commercial culture of octopus and cuttlefish (Section 4). Current fishery data collection and fishery management are described, noting that there is no setting of landings quotas and no routine assessment of stock status. Optns for stock assessment are discussed, drawing on one off assessments made during specific projects and current practice elsewhere in the world. The “live fast, die yong” lifehistory strategies of cephalopods present particular challenges, buparallels can be drawn with shortlived fish (Section 5). Finally, the report looks to the future, reviewing possible effects of climate change on cephalopods. It discusses the future development of aquaculture and fisheries for cephalopods, including prospects for fishery forecasting and fishery management - especially in relation to the small-scale directed fisheries. Various knowledge gaps are identified, and ideas for research to fill these gaps are presented

We report a record of the largest known specimen of Ommastrephes bartramii. It was an almost mature female, with dorsal mantle length (ML) of 1020 mm and weighing around 35 kg, caught by a Spanish fishing vessel in October 2007 on a surface long-line in the Eastern Tropical Pacific. Growth increments on a statolith indicate an age of 492-512 days. The stomach was full and contained beaks of ommastrephid squids and of a small pelagic octopus (Japetella spp.), and remains of mackerel (possibly bait from the long-line) and unidentified fish., En este trabajo se presenta información sobre el mayor ejemplar de Ommastrephes bartramii descrito hasta la actualidad. Se trata de una hembra casi madura, cuya longitud dorsal del manto es de 1020 mm y con un peso total de aproximadamente 35 kg, capturada en octubre de 2007 por un pesquero español utilizando palangre de superficie en el Pacífico Tropical Este. Los incrementos de crecimiento observados en un estatolito indican una edad comprendida entre 492 y 512 días. El estómago estaba lleno y contenía picos de potas (omastréfidos) y de un pulpo pelágico pequeño (Japatella spp.), así como restos de caballas (posiblemente cebo del palangre) y de otros peces que no pudieron ser identificados.

Over the past two decades, cephalopod molluscs have attracted increased attention from marine biologists and fishery scientists. Several species are important for European fisheries, as targets of small-scale coastal fisheries and/or as bycatch in multispecies fisheries for demersal fish. The present report draws on a series of reviews prepared in 2005 for the CEPHSTOCK project (see Section 1). The taxonomy of the main resource species is reviewed (Section 2), and brief descriptions of each species are provided, along with information from studies of population genetics, habitat requirements of paralarvae and adults, and health and ecotoxicology (Section 3). The main fisheries are described, including illustration of gears used in specialized small‐scale fisheries and a discussion of the socio-economic importance of the fisheries. The current status of cephalopod aquaculture is reviewed, highlighting notable advances in commercial culture of octopus and cuttlefish (Section 4). Current fishery data collection and fishery management are described, noting that there is no setting of landings quotas and no routine assessment of stock status. Optns for stock assessment are discussed, drawing on one off assessments made during specific projects and current practice elsewhere in the world. The “live fast, die yong” lifehistory strategies of cephalopods present particular challenges, buparallels can be drawn with shortlived fish (Section 5). Finally, the report looks to the future, reviewing possible effects of climate change on cephalopods. It discusses the future development of aquaculture and fisheries for cephalopods, including prospects for fishery forecasting and fishery management - especially in relation to the small-scale directed fisheries. Various knowledge gaps are identified, and ideas for research to fill these gaps are presented