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Campañas de Ictioplancton para Evaluación de Stocks, CIES, EVALICES2, Evaluación de Recursos Marinos Vivos en el Área ICES

In habitat modelling, environmental variables are assumed to be proxies of lower trophic levels distribution and by extension, of marine top predator distributions. More proximal variables, such as potential prey fields, could refine relationships between top predator distributions and their environment. In situ data on prey distributions are not available over large spatial scales but, a numerical model, the Spatial Ecosystem And POpulation DYnamics Model (SEAPODYM), provides simulations of the biomass and production of zooplankton and six functional groups of micronekton at the global scale. Here, we explored whether generalised additive models fitted to simulated prey distribution data better predicted deepdiver densities (here beaked whales Ziphiidae and sperm whales Physeter macrocephalus) than models fitted to environmental variables. We assessed whether the combination of environmental and prey distribution data would further improve model fit by comparing their explanatory power. For both taxa, results were suggestive of a preference for habitats associated with topographic features and thermal fronts but also for habitats with an extended euphotic zone and with large prey of the lower mesopelagic layer. For beaked whales, no SEAPODYM variable was selected in the best model that combined the two types of variables, possibly because SEAPODYM does not accurately simulate the organisms on which beaked whales feed on. For sperm whales, the increase model performance was only marginal. SEAPODYM outputs were at best weakly correlated with sightings of deep-diving cetaceans, suggesting SEAPODYM may not accurately predict the prey fields of these taxa. This study was a first investigation and mostly highlighted the importance of the physiographic variables to understand mechanisms that influence the distribution of deep-diving cetaceans. A more systematic use of SEAPODYM could allow to better define the limits of its use and a development of the model that would simulate larger prey beyond 1,000 m would probably better characterise the prey of deep-diving cetaceans.

Aim Deep-diving cetaceans are oceanic species exposed to multiple anthropogenic pressures including high intensity underwater noise, and knowledge of their distribution is crucial to manage their conservation. Due to intrinsic low densities, wide distribution ranges and limited presence at the sea surface, these species are rarely sighted. Pooling data from multiple visual surveys sharing a common line-transect methodology can increase sightings but requires accounting for heterogeneity in protocols and platforms. Location North Atlantic Ocean and Mediterranean Sea. Time period 1998 to 2015. Major taxa Ziphiidae; Physeteriidae; Kogiidae. Methods About 1,240,000 km of pooled effort provided 630 sightings of ziphiids, 836 of physeteriids and 106 of kogiids. For each taxon, we built a hierarchical model to estimate the effective strip width depending on observation conditions and survey types. We then modelled relative densities in a generalized additive modelling framework. Geographical predictions were limited to interpolations identified with a gap analysis of environmental space coverage. Results Deeper areas of the North Atlantic gyre were mostly environmental extrapolation in the predictions, thereby highlighting gaps in sampling across the different surveys. For the three species groups, the highest relative densities were predicted along continental slopes, particularly in the western North Atlantic Ocean where the Gulf Stream creates dynamic frontal zones and eddies. Main conclusions Pooling a large number of surveys provided the first basin-wide models of distribution for deep-diving cetaceans, including several data-deficient taxa, across the North Atlantic Ocean and the Mediterranean Sea. These models can help the conservation of elusive and poorly known marine megafauna., SI

The marine environment faces an increasing number of threats, mainly driven by anthropogenic activities, that are causing growing impacts on marine species and processes. In Europe, the EU Marine Strategy Framework Directive (MSFD) aims to achieve or maintain Good Environmental Status (GES) of the European waters by 2020. The Directive specifically refers to biodiversity with the first of the eleven qualitative descriptors (proposed to help describe what GES should look like) being Biodiversity is maintained. For this descriptor, the status of several functional groups, including marine megafauna species, need to be assessed using criteria such as population size and condition, and mortality due to bycatch in fishing gear, that compare current values against agreed thresholds. To contribute to this process, we performed an assessment of the threats affecting the marine megafauna community (i.e. seabirds and cetaceans) in the Bay of Biscay synthesizing the available evidences and identifying the main threats affecting the marine megafauna to help prioritise the required management and conservation actions. We analysed 4,023 admissions of seabirds recorded during 2004–2016 from four Wildlife Rehabilitation Centres to obtain an initial quantitative assessment of the pressures exerted on seabirds. The main marine threats identified in the Spanish North Atlantic sub-region were cachexia (52.3%), exposure to crude oil (10%) and interaction with fishing gears (5.3%). When considering all threats together, the common guillemot, the yellow-legged gull, the northern gannet, the great cormorant and the razorbill were the main affected species. In addition, we summarised the available information to perform an updated qualitative assessment of the severity of the threats faced by seabirds and cetaceans. The qualitative assessment showed that cetaceans are especially vulnerable to bycatch, vessel collision, and pollution-related threats, whilst seabirds are particularly sensitive to oil spills, bycatch and marine litter. This type of assessment studies can aid in the identification of priority areas and/or species where management measures should be applied to ensure that the ultimate goal of the MSFD, sustainable conservation of the marine environment, is reached., Sí

This Special Issue on Crustacean Genomics arises from the TCS 2017 conference held in Barcelona, Spain, between 19 and 22 June, 2017. Applications of next generation sequencing have expanded rapidly over recent years, unveiling many new and exciting areas of genomic research. This includes novel insights into physiology, reproductive biology, response to environmental challenges, and their evolutionary history. Despite their importance, crustaceans still lack genomic resources compared with other widely-studied groups such as insects and vertebrates. The present volume integrates a collection of contributions from the speakers, and compiles the main results presented during the symposium. Following the structure of the Crustacean Genomics workshop, contributed papers have been arranged in two main blocks, a first set of studies focused on the use of transcriptomics to investigate crustacean physiology and reproduction while the second set focused on molecular systematics and evolutionary studies.

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The Working Group on Marine Mammal Ecology (WGMME), chaired by Begoña Santos (Spain) and Graham Pierce (Spain), met in St Andrews, UK 6–9 February 2017. It report-ed on recent information on status of, and threats to, marine mammal populations and briefly reviewed current knowledge of effects of plastics and underwater noise. Direct interactions between seals and fisheries were reviewed and the group also reported on the current status of the ICES / OSPAR seal database(s). The group provided text for five ecosystem overviews. Criteria for assessment of abundance trends in offshore cetaceans in the context of the MSFD were reviewed, modifying the proposed indicator (previously based solely on the rate of decline) to make specific reference to baseline values. Linked to this, the group reported on the outcomes of the 2016 SCANS III survey. Given that the three main large-scale surveys of cetaceans in European Atlantic waters have all arisen from individual projects and were separated by intervals of eleven years, there is concern as to the future and utility of these surveys. WGMME recommends that the surveys be co-organised and coordinated by Member States as part of their routine monitoring and that the frequency is increased to once every six years to match the MSFD reporting cy-cle.

This study describes fisheries, stock status, ICES advice and management measures for the Northern and Southern sardine stocks in EU Atlantic waters. Information on sardine biology and ecology is provided for a better understanding of stock development. Social and economic dimensions are addressed for sardine fisheries in France, Spain and Portugal. The study provides recommendations to improve knowledge on the species and indicates management measures which might be considered for the sustainability of the fisheries. Versión del editor

The Spanish acoustic-trawl times PELACUS 0314 was carried out on board R/V Miguel Oliver from 9th March to 8th April, covering the north Spanish waters (Atlantic and Bay of Biscay) from the coast to the 1000 m isobath on a systematic grid with tracks 8 nmi apart and equally spaced. Acoustic , fishing stations, fish egg counting, microplastic, and apical predators observations were done during daytime whilst the oceanographic characterisation was done during night time. A total of 1903 nautical miles were steamed, 1075 corresponding to the survey track. Besides 52 fishing stations were performed (Figure 2). PELCACUS 0314 was characterised by relative stable weather conditions along the surveyed area. Besides, there was an important increase in backscattering energy as compared with the previous year. This resulted in an increase of the biomass estimated for the majority of the fish species, but still sardine is at lowest productivity ever recorded. Good recruitment would be observed in horse mackerel, but for the rest of the fish species, no strong signals for age group 1 have been detected. The reasons for this increase would be related to the weather stability which could have increased the fish availability either for a change in the behaviour (i.e. spatial pattern distribution) or for an increase in the food availability. This is relevant accounting the increase of the occurrence of mackerel subsurface layers observed this year. As PELACUS is a multidisciplinary survey series (we collect environmental and biological ancillary information, stomach contents, including CTD cats, plankton tows or continuous records of plankton, eggs, S, T and flourometry), we will try to explain this change of behaviour. Our main hypothesis is that these species could follow mackerel when is undertaking vertical migration, probably related with the spawning activity, just for feeding eggs and, therefore, changing the expected schooling behaviour by the dispersed one, used during the feeding activity.

As part of a project which aimed to evaluate the feasibility of developing indicators of marine ecosystem status based on cephalopods, we analysed spatiotemporal variation in abundance,, and environmental relationships, using trawl survey catch data for cephalopods in UK waters (1980-2013) from Cefas and Marine Scotland Science databases. These data presented some challenges, notably the use of several different trawl gears, variable tow durations, and varying levels of taxonomic resolution. Accounting for gear type and tow duration, data were analysed separately for each cephalopod family and season to account for different phases of the life cycles being present at different times of year. The families investigated were Loliginidae, Octopodidae, Ommastrephidade, Sepiidae and Sepiolidae. A GAM framework was used to summarise spatiotemporal variation in abundance at family level and the relationships of spatial and long-term temporal variation with environmental variables, including depth, substrate (available for inshore waters) and several oceanographic variables (e.g., SST, chl signals), also considering fishing pressure. Long-term trends for each family varied between areas and seasons, although this may reflect the presence of several species within families. In Scotland, where Loligo vulgaris is rare and L. forbesii is normally distinguished from Alloteuthis spp., survey data suggested a peak in abundance of this species around 1990 and a generally increasing trend since the mid-1990s. Spatial patterns in distribution in all families were related to both physiographic and oceanographic features. As expected substrate type had most effect on those families in which eggs are attached to objects on the seabed.

Bycatch from interactions with fisherie s remains the biggest global threat to marine mammals. Galicia, north - west Spain, is one of the world’s main fishing regions and a high level of cetacean - fisheries interactions has been reported from on - board observers, interviews with fisheries stakeholde rs and analysis of stranded and by - caught carcasses. Delphinus delphis is the most abundant cetacean in the area and since 1990 necropsies of over 1800 stranded and by - caught Delphinus have been conducted. Life history data (age, maturity, and pregnancy ra te data) from stranded and by - caught cetaceans can be used to construct life tables and to estimate overall mortality and fisheries mortality rates. Age and maturity were determined from stranded and by - caught Delphinus between 1990 and 2009. Males and fem ales reach sexual maturity at 8.5 and 7.5 years of age, respectively, and no temporal difference in age at sexual maturity was observed. Results indicate 13% annual mortality in the Delphinus delphis north - east Atlantic population and necropsy data suggest s that 60% of mortality (i.e. 7.2% annual mortality) is attributable to fisheries interactions, predominantly from pair trawls and gillnets. By - caught Delphinus were found to die significantly younger than non - by - caught animals (p=

Existe muy poca información sobre la dieta del delfín listado (Stenella coeruleoalba) en aguas del sur de España. En este estudio se analizaron los estómagos de 61 delfines varados en Andalucía en los últimos ocho años (2007-2014). Diez estómagos estaban vacios y de los 51 individuos restantes, 35 vararon en la costa del Mar de Alborán y 11 en el Golfo de Cádiz. Para las 5 muestras restantes no se dispone de localidad concreta. Los restos de las presas en los estómagos consistieron sobre todo en estructuras duras: otolitos, cristalinos y unos pocos huesos de peces, así como mandíbulas y cristalinos de cefalópodos. No aparecieron otro tipo de restos lo que parece indicar que los individuos no se habían alimentado recientemente. Para caracterizar la dieta se calcularon tres índices (calculados para cada categoría de presa): frecuencia de aparición en los estómagos, número de individuos y peso reconstruido y sus porcentajes respectivos. El delfín listado parece ser una especie predominantemente piscívora (se identificaron restos de 5682 peces frente a solamente 210 cefalópodos) que se alimenta de especies mesopelágicas principalmente. La familia más importante tanto en número como en frecuencia de aparición fue Myctophidae, principalmente Ceratoscopelus maderensis y Myctophum punctatum a las que pertenecieron casi la mitad de los peces identificados (36,4%N, 35,3%F y 12,3%N, 25,5%F, respectivamente). También se identificó Maurolicus muelleri (Sternoptychidae 13,4%N y 17,6%F). Otras familias identificadas presentan una distribución más costera: Sparidae (Boops boops) y Carangidae (Trachurus sp.) (4,5%N, 9,8%F y 1,2%N, 3,9%F, respectivamente). Los cefalópodos identificados pertenecieron a 11 familias siendo la más abundante Ommastrephidae (26,7%N y 39,2%F). Otras familias incluyen representantes oceánicos, Brachioteuthidae (16,7%N y 21,5%F); Chiroteuthidae (6,7%N y 9,8%F); Enoploteuthidae (4,8%N y 3,9%F), Ancistrocheridae (0.5%N y 2%F) y otros de distribución más costera, Sepiolidae (19%N y 19,6%F), Sepiidae (5,7%N y 3,9%F) y Loliginidae (3,8%N y 5,9%F).

En prensa

Con el fin de identificar áreas ecológicamente significativas, necesitamos relacionar la distribución de especies con descriptores ecológicos que nos ayuden a comprender su distribución. En el medio marino, los modelos de distribución de especies (MDE) han sido tradicionalmente desarrollado en base a descriptores ecológicos indirectos (como clorofila y temperatura superficial del mar) recogidos a través de imágenes de satélite. Aunque las especies marinas pueden utilizar estas señales ambientales para localizar sus presas, el uso de información sobre la distribución de las mismas sería más informativo que el uso de estos descriptores indirectos. Gracias a las campañas oceanográficas multidisciplinares se puede recoger información simultánea de varios niveles tróficos, desde el plancton a los depredadores marinos, incluyendo sus principales presas pelágicas: los pequeños peces pelágicos. Por lo tanto, la inclusión de esta información en los MDE debería ser más relevante que las variables oceanográficas indirectas. Para testar esta hipótesis, desarrollamos MDE para las tres especies más abundantes de cetáceos que se registran en el norte de la Península Ibérica durante las campañas de primavera del Instituto Español de Oceanografía, PELACUS (2007-2013). Estas especies fueron el delfín común Delphinus delphis, el delfín mular Tursiops truncatus y el calderón común Globicephala melas. Dependiendo de las especies consideradas, se identificaron diferentes variables ambientales como importantes a la hora de explicar los patrones de distribución; pero las cifras globales ponen de manifiesto la principal contribución de la batimetría, seguido de la temperatura superficial del mar y la variabilidad espacial en la distribución de los pequeños peces pelágicos. Estos resultados tienen importantes implicaciones en reconocer la importancia de los estudios oceanográficos multidisciplinares para la obtención de descriptores ecológicos directos para mejorar los modelos de distribución de depredadores marinos.

El objetivo de las Estrategias Marinas es permitir el uso sostenible del medio marino mediante la gestión de las actividades y presiones humanas siguiendo un enfoque ecosistémico. La evaluación del estado de conservación de las especies marinas y su monitorización para determinar si alcanza el Buen Estado Ambiental (BEA) son sus pilares básicos. Para establecer medidas de gestión que permitan a una población alcanzar el BEA, se debe estudiar el estado de la misma y el efecto que diferentes niveles de amenazas antropogénicas pueden tener sobre ella. La creación de modelos dinámicos permite estudiar las posibles trayectorias de una población ante diferentes escenarios. La fuente de información biológica más importante que poseemos es aquella proveniente de los varamientos, que también proporcionan información sobre la causa de la muerte. El análisis de las muestras de individuos varados nos permite calcular tasas de natalidad, mortalidad, estructura de edad poblacional y el impacto directo o indirecto de las presiones antropogénicas (captura accidental, colisiones con embarcaciones, contaminación, etc.). Asimismo, los patrones observados en los varamientos nos dan información sobre la tendencia en la abundancia de una especie y sobre posibles desplazamientos. La abundancia de una población puede ser obtenida mediante campañas de avistamiento y, dependiendo de la metodología empleada, pueden obtenerse estimas relativas o absolutas. Además, la dieta de los cetáceos nos permite estudiar sus preferencias alimentarias y el papel que pueden estar jugando en el ecosistema. Los modelos multiespecíficos (p.ej. Gadget) posibilitan estudiar su interacción con los stocks pesqueros e informar una gestión ecosistémica. En este trabajo se presentan datos preliminares sobre abundancia del delfín común en el N y NW peninsular, tendencias en la abundancia, parámetros biológicos y su estructura poblacional, mortalidad natural, pesquera y ejemplos de puntos de referencia que permitan determinar si la población alcanza el BEA.

El objetivo de este trabajo es detallar el proceso de construcción de modelos poblacionales para las principales especies de cetáceos en aguas atlánticas de la Península Ibérica a partir de las fuentes de información disponibles. La importancia de la disponibilidad de modelos dinámicos radica en que permiten seguir las trayectorias de las poblaciones ante diferentes escenarios posibilitando así informar sobre posibles medidas de gestión para una conservación efectiva de estas especies, protegidas tanto por legislación nacional como europea. La fuente de información biológica más importante que poseemos es aquella proveniente de los varamientos, ya que por motivos obvios no podemos muestrear a los individuos directamente. A partir del examen de los ejemplares varados y la toma de muestras se obtiene la talla de los individuos, el peso, la edad, la madurez, y se derivan estimas poblacionales (a partir de nuestra muestra) como tasas de natalidad, mortalidad, estructura de edad poblacional y una tasa del impacto que, a nivel poblacional, pueden estar teniendo las diferentes presiones antrópicas a las que están sometidos. Para interpretar las tendencias temporales y espaciales en los patrones de mortalidad derivados de los varamientos, se puede utilizar información complementaria como la variabilidad de los índices oceanográficos y la actividad pesquera. Además, dado que los cetáceos son unos de los principales predadores de nuestras costas y ejercen gran influencia en la regulación del ecosistema en el que habitan, los modelos poblacionales también nos permiten, a partir de su inclusión en modelos multiespecíficos, estudiar su interacción con los stocks pesqueros de los que se alimentan, evaluar su papel en los ecosistemas y contribuir a la mejora de los actuales modelos de gestión pesquera.

The short-beaked common dolphin (Delphinus delphis) is the most abundant small cetacean in the north eastern Atlantic and in some regions by-catch is considered to be unsustainable. To help inform conservation measures, population models are needed to explore how the population will react under different scenarios. In order to build a population model, mortality-at-age curves derived from stranding data were constructed, using a Siler model fitted to the total observed dataset. Due to the paucity of data for the youngest age classes, a separate model was fit to a subset of the data that did not include the youngest age classes. Finally, a Heligman-Pollard model was fitted to the second subset of data as well, taking into account the proportion of by-caught dolphins in the sample. The survivorship curves for the Siler models reported that a median of 30% of the females achieve maturity when we used the total observed data set but only the 18% if we remove the youngest ages. The Heligman-Pollard model showed a more realistic shape since by-catch mortality was taken into account. The results of this model show an effective growth of 0.912 which indicate a population decline, likely due to high rates of by-catch.

There is little previous information on feeding habits of long-finned pilot whales (Globicephala melas) in the northeast Atlantic. The present study analyzed stomach contents of pilot whales stranded in Portugal (n = 6), Galicia (northwest Spain) (n = 32), and Scotland (United Kingdom) (n = 10), from 1990 to 2011. These animals ranged from 213 to 555 cm in length (24 females, 19 males and 5 of unknown sex). The main prey identified were cephalopods of the families Octopodidae and Ommastrephidae, the former being numerically more important in Iberia (Portugal and Galicia) and the latter more important in Scotland, with Iberian whales also showing a more diverse diet. Multivariate analysis revealed evidence of geographical and seasonal variation in diet. Generalized Additive Modeling results indicated that more octopus (Eledone cirrhosa) were eaten in Iberia than in Scotland, more in the first half of the year, and more in larger whales. Numbers of ommastrephid squids in the stomach decreased over the study period and varied with season and whale length. This study confirms cephalopods as the main prey of pilot whales, as previously reported, although our results also suggest that, in the northeast Atlantic, ommastrephid squid are largely replaced as the main prey by octopods at lower latitudes., Sí

The European Union has adopted the Marine Strategy Framework Directive (MSFD, Directive 2008/56/EC) with the objective of achieving or maintaining Good Environmental Status (GES) of European waters by 2020. The MSFD constitutes the legislative instrument devised to protect the marine environment across European waters from the human-­‐related environmental changes that had already negatively affected marine ecosystem functioning and the dynamics of many populations of marine organisms. To achieve GES, Member States will need to address all human activities that have an impact on the marine environment, through an integrated ecosystem-­‐based approach that is spatially explicit. Multidisciplinay surveys are an ideal platform that can provide a synoptic view of the status of marine habitats. PELACUS surveys are conducted annually for acoustic assessment and mapping of the oceanographic and biological conditions of the northern and northwestern shelf of the Iberian Peninsula. The main objective is to monitor the pelagic ecosystem collecting concurrent information on several trophic levels. Since 2007, marine mammal and seabirds sightings have been recorded by dedicated observers, who also collect information on the type and abundance of different types of human pressures (e.g. fishing, marine debris). Using distance sampling methodology, we were able to estimate relative abundance of marine predator species in the region in addition to mapping the areas where they could be more at risk from anthropogenic pressures such as fishing and marine litter. Our objective is to highlight the importance of observer programmes not only in providing (1) baseline information on distribution and abundance of top predators, but (2) also additional information on human pressures. Both types of data are needed to inform any conservation and management plans such as the MSFD.

This study demonstrates the utility of trawl data, collected during acoustic surveys of pelagic fish stocks as a way of confirming fish identification, to characterize the pelagic community, as well as allowing description and prediction of fish distribution patterns, based on data from Spanish Atlantic Ocean shelf surveys during spring 2005–2011. The composition of the pelagic community is described, as well as spatial and temporal patterns of variation in both the community composition and the presence and importance of two of the main exploited pelagic species, sardine Sardina pilchardus and anchovy Engraulis encrasicolus. The most important species in terms of both frequency of occurrence and standardized mass in hauls were mackerel Scomber scombrus, hake Merluccius merluccius, horse mackerel Trachurus trachurus, S. pilchardus and bogue Boops boops. Multivariate analysis indicated significant effects of depth, geographical area and year on haul composition. Descriptive generalized additive models (GAM), with latitude, longitude and depth as predictors, identified clear spatial patterns in the occurrence and abundance of both S. pilchardus and E. encrasicolus, with abundance being highest closer to the coast and, in the case of E. encrasicolus, higher near the French and Portuguese borders. Further GAM analysis, using environmental variables to explain spatial patterns, revealed significant effects of depth and sea surface temperature (SST) gradient and depth on S. pilchardus importance, while E. encrasicolus importance was related to SST. The importance of both species in hauls was higher in the years of higher spawning stock biomass (SSB) and E. encrasicolus also appeared to expand its range when SSB was higher. 2