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Fish body condition and growth are two interrelated traits closely associated with species life history and fitness, whose trade-off can ultimately impact population dynamics albeit seldom empirically demonstrated. They can intricately affect survival rates, which are particularly relevant for species under exploitation. Using individual spatiotemporal information in Northwestern Mediterranean, we document for the first time the existence of a trade-off between condition and growth in regulating survival dynamics in two important fish species for the Mediterranean fisheries that are characterized by contrasting life histories. For the European hake (Merluccius merluccius), a benthopelagic species, juveniles' body condition was detected to be positively linked to survival and negatively associated with the growth of this age group. For the red mullet (Mullus barbatus), the same pattern was observed for young adults. We also show that the observed patterns on a regional level have a clear spatial dependence as we found that observed body condition over a local scale had a broad effect on the population dynamics of the whole region, with the Ebro delta area emerging as the demographic engine of the two species. We discuss our results in the context of fisheries management and underline the importance of improving current stock assessment models and spatially based fishery management towards incorporating body condition and growth due to their influence on important parameters such as survival.

[EN] This study analyses information on blue shark catches from the longline fleet operating in Spanish Mediterranean waters. Data from observers and logbooks have been used to provide an exploratory analysis of the main factors associated with such catches. Catch per Unit of Effort (CPUE) has been calculated as the number of individuals caught per thousand hooks. Differences in catches and CPUEs have been observed for the different types of longline used, as well as spatio-temporal patterns. In addition, basic biological information on the BSH caught is provided. Further analysis can provide more accurate information on important aspects such as inter- and intra-annual variation in catches and identification of potential areas of higher concentration of catches of BSH., [FR] Cette étude analyse des informations sur les captures de requin peau bleue réalisées par la flottille palangrière opérant dans les eaux espagnoles de la Méditerranée. Les données des observateurs et des carnets de pêche ont été utilisées pour fournir une analyse exploratoire des principaux facteurs associés à ces captures. La capture par unité d’effort (CPUE) a été calculée en tant que nombre de spécimens capturés par mille hameçons. Des différences dans les captures et les CPUE ont été observées pour les différents types de palangre utilisés ainsi que des schémas spatio-temporels. Ce document fournit également des informations biologiques de base sur les BSH capturés. Une analyse plus approfondie peut apporter des informations plus précises sur certains aspects importants, comme la variation inter-annuelle et intra-annuelle des captures et l’identification des zones potentielles de plus forte concentration de captures de BSH., [ES] Este estudio analiza la información sobre las capturas de tiburón azul de la flota palangrera que opera en aguas del Mediterráneo español. Se han utilizado los datos de los observadores y de los cuadernos de pesca para proporcionar un análisis exploratorio de los principales factores asociados a dichas capturas. La captura por unidad de esfuerzo (CPUE) se ha calculado como el número de ejemplares capturados por cada mil anzuelos. Se han observado diferencias en las capturas y las CPUE para los distintos tipos de palangre utilizados, así como patrones espaciotemporales. Además, se ofrece información biológica básica sobre el tiburón azul capturado. Un análisis más detallado puede proporcionar información más precisa sobre aspectos importantes como la variación interanual e intraanual de las capturas y la identificación de posibles zonas de mayor concentración de capturas de tiburón azul.

[EN] A variety of candidate management procedures (CMPs) were developed and tested in the management strategy evaluation (MSE) of the northern swordfish fishery. The performance of the CMPs was evaluated across a set of nine reference operating models and five robustness models. The reference operating models spanned the uncertainty in the natural mortality rate and the steepness of the Beverton-Holt stock-recruit relationship. The robustness tests considered additional uncertainties, including hyperstability in the indices of abundance, the influence of climate change on future recruitment, and the impact of illegal, unreported, and unregulated fishing. A set of performance metrics (PMs) were defined to calculate the performance of the CMPs. The PMs included metrics related to the biological status of the stock, the probability of breaching the limit reference point, and the magnitude and variability of the total allowable catch recommendations from each CMP. The results from the MSE are presented in an interactive application. This paper provides an overview of the technical specifications of the north Atlantic swordfish MSE and describes the figures and tables that are available in the interactive application., [FR] Plusieurs procédures de gestion potentielles (CMP) ont été développées et testées dans le cadre de l’évaluation de la stratégie de gestion (MSE) de la pêcherie d’espadon du Nord. La performance des CMP a été évaluée sur un ensemble de neuf modèles opérationnels de référence et cinq modèles de robustesse. Les modèles opérationnels de référence couvraient l’incertitude dans le taux de mortalité naturelle et la pente de la relation stock-recrutement de Beverton-Holt. Les tests de robustesse étudiaient des incertitudes additionnelles, dont l’hyperstabilité des indices d’abondance, l’influence du changement climatique sur le futur recrutement et l’impact de la pêche illicite, non déclarée et non réglementée. Un ensemble de mesures de performance (PM) ont été définies pour calculer la performance des CMP. Les PM incluaient des mesures liées à l’état biologique du stock, la probabilité de dépasser le point de référence limite et l’ampleur et la variabilité du total admissible de captures recommandé par chaque CMP. Les résultats de la MSE sont présentés dans une application interactive. Ce document offre un aperçu des spécifications techniques de la MSE de l’espadon de l’Atlantique Nord et décrit les figures et tableaux qui sont disponibles dans l’application interactive., [ES] En la evaluación de la estrategia de ordenación (MSE) de la pesquería de pez espada del norte se desarrollaron y probaron diversos procedimientos de ordenación candidatos (CMP). El desempeño de los CMP se evaluó a través de un conjunto de nueve modelos operativos de referencia y cinco modelos de robustez. Los modelos operativos de referencia abarcaban la incertidumbre de la tasa de mortalidad natural y la inclinación de la relación stock-reclutamiento de Beverton-Holt. Las pruebas de robustez tuvieron en cuenta incertidumbres adicionales, como la hiperestabilidad en los índices de abundancia, la influencia del cambio climático en el reclutamiento futuro y el impacto de la pesca ilegal, no declarada y no reglamentada. Se definió un conjunto de métricas de desempeño (PM) para calcular el desempeño de los CMP. Las PM incluían métricas relacionadas con el estado biológico del stock, la probabilidad de superar el punto de referencia límite y la magnitud y variabilidad del total admisible de capturas recomendadas por cada CMP. Los resultados de la MSE se presentan en una aplicación interactiva. Este documento ofrece una visión general de las especificaciones técnicas de la MSE del pez espada del Atlántico norte y describe las figuras y tablas disponibles en la aplicación interactiva.

[EN] This document describes proposed updates to the North Atlantic Swordfish Management Strategy Evaluation Process including revisions to operating models and performance metrics. Many of these revisions are in response to the SCRS’s discussion with Panel 4 in March of 2023., [FR] Le présent document décrit les actualisations proposées au processus d'évaluation de la stratégie de gestion de l'espadon de l'Atlantique Nord, comprenant les révisions des modèles opérationnels et des mesures de performance. Bon nombre de ces révisions font suite à la discussion du SCRS avec la Sous-commission 4 au mois de mars 2023., [ES] Este documento describe las actualizaciones propuestas para el proceso de evaluación de la estrategia de ordenación para el pez espada del Atlántico norte, incluidas las revisiones de los modelos operativos y las mediciones de desempeño. Muchas de estas revisiones responden al debate del SCRS con la Subcomisión 4 en marzo de 2023.

Experiments based on the premise of uniformitarism are an effective tool to establish patterns of taphonomic processes acting either before, or after, burial. One process that has been extensively investigated experimentally is the impact of trampling to large mammal bones. Since trampling marks caused by sedimentary friction strongly mimic cut marks made by humans using stone tools during butchery, distinguishing the origin of such modifications is especially relevant to the study of human evolution. In contrast, damage resulting from trampling on small mammal fossil bones has received less attention, despite the fact that it may solve interesting problems relating to site formation processes. While it has been observed that the impact of compression depends on the type of substrate and dryness of the skeletal elements, the fragility of small mammal bones may imply that they will break as a response to compression. Here, we have undertaken a controlled experiment using material resistance compression equipment to simulate a preliminary experiment, previously devised by one of us, on human trampling of owl pellets. Our results demonstrate that different patterns of breakage can be distinguished under wet and dry conditions in mandibles, skulls and long bones that deform or break in a consistent way. Further, small compact bones almost always remain intact, resisting breakage under compression. The pattern obtained here was applied to a Pleistocene small mammal fossil assemblage from Wonderwerk Cave (South Africa). This collection showed unusually extensive breakage and skeletal element representation that could not be entirely explained by excavation procedures or digestion by the predator. We propose that trampling was a significant factor in small mammal bone destruction at Wonderwerk Cave, partly the product of trampling caused by the raptor that introduced the microfauna into the cave, as well as by hominins and other terrestrial animals that entered the cave an, Ministerio de Ciencia e Innovación (MICINN), Consejo Superior de Investigaciones Científicas (CSIC), Leakey Foundation, Universidad Complutense de Madrid/Banco de Santander, Canadian Social Sciences and Humanities Research Council, Université de Rennes 1, Museo Nacional de Ciencias Naturales, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

Experiments based on the premise of uniformitarism are an effective tool to establish patterns of taphonomic processes acting either before, or after, burial. One process that has been extensively investigated experimentally is the impact of trampling to large mammal bones. Since trampling marks caused by sedimentary friction strongly mimic cut marks made by humans using stone tools during butchery, distinguishing the origin of such modifications is especially relevant to the study of human evolution. In contrast, damage resulting from trampling on small mammal fossil bones has received less attention, despite the fact that it may solve interesting problems relating to site formation processes. While it has been observed that the impact of compression depends on the type of substrate and dryness of the skeletal elements, the fragility of small mammal bones may imply that they will break as a response to compression. Here, we have undertaken a controlled experiment using material resistance compression equipment to simulate a preliminary experiment, previously devised by one of us, on human trampling of owl pellets. Our results demonstrate that different patterns of breakage can be distinguished under wet and dry conditions in mandibles, skulls and long bones that deform or break in a consistent way. Further, small compact bones almost always remain intact, resisting breakage under compression. The pattern obtained here was applied to a Pleistocene small mammal fossil assemblage from Wonderwerk Cave (South Africa). This collection showed unusually extensive breakage and skeletal element representation that could not be entirely explained by excavation procedures or digestion by the predator. We propose that trampling was a significant factor in small mammal bone destruction at Wonderwerk Cave, partly the product of trampling caused by the raptor that introduced the microfauna into the cave, as well as by hominins and other terrestrial animals that entered the cave an

Experiments based on the premise of uniformitarism are an effective tool to establish patterns of taphonomic processes acting either before, or after, burial. One process that has been extensively investigated experimentally is the impact of trampling to large mammal bones. Since trampling marks caused by sedimentary friction strongly mimic cut marks made by humans using stone tools during butchery, distinguishing the origin of such modifications is especially relevant to the study of human evolution. In contrast, damage resulting from trampling on small mammal fossil bones has received less attention, despite the fact that it may solve interesting problems relating to site formation processes. While it has been observed that the impact of compression depends on the type of substrate and dryness of the skeletal elements, the fragility of small mammal bones may imply that they will break as a response to compression. Here, we have undertaken a controlled experiment using material resistance compression equipment to simulate a preliminary experiment, previously devised by one of us, on human trampling of owl pellets. Our results demonstrate that different patterns of breakage can be distinguished under wet and dry conditions in mandibles, skulls and long bones that deform or break in a consistent way. Further, small compact bones almost always remain intact, resisting breakage under compression. The pattern obtained here was applied to a Pleistocene small mammal fossil assemblage from Wonderwerk Cave (South Africa). This collection showed unusually extensive breakage and skeletal element representation that could not be entirely explained by excavation procedures or digestion by the predator. We propose that trampling was a significant factor in small mammal bone destruction at Wonderwerk Cave, partly the product of trampling caused by the raptor that introduced the microfauna into the cave, as well as by hominins and other terrestrial animals that entered the cave an

Introducción: La extracción de un diente genera cambios morfológicos y fisiológicos a nivel alveolar. Las técnicas de preservación alveolar tienen como principal objetivo limitar dichos cambios tras la exodoncia, con la finalidad de que, una vez finalizado el proceso de cicatrización, se disponga de un volumen óseo que facilite una rehabilitación protésica lo más estética y funcional posible tras la inserción de los implantes osteointegrados. Objetivos: Evaluar los efectos del injerto de dentina desmineralizada y plasma rico en fibrina en la preservación alveolar. Material y métodos: Caso clínico realizado en la Unidad Docente de Cirugía Oral de la USC, en un paciente varón joven, en el que inicialmente se le había planificado la exodoncia de un canino incluido a nivel palatino y colocación simultánea de un implante inmediato posextracción. Sin embargo, la amplia ostectomía necesaria para la extracción del canino, el gran tamaño de la cápsula eruptiva que rodeaba al diente incluido y la escasa disponibilidad ósea, aconsejaron demorar la inserción del implante a un segundo tiempo quirúrgico Conclusiones: El injerto de dentina desmineralizada es considerada una nueva opción terapéutica ante aquellos casos clínicos en los que se requiere obtener una importante cantidad de injerto. Con los estudios que disponemos en la actualidad, podemos afirmar que el injerto de dentina autóloga no provoca reacciones desfavorables, por lo que su integración biológica y funcional es rápida, efectiva y predecible, Introduction: The extraction of a tooth generates morphological and physiological changes at the alveolar level. The main objective of alveolar preservation techniques is to limir these changes after the extraction, so that, once the healing process is finished, there is a bone volumen that facilitates the most aesthetic and functional prosthetic rehabilitation posible after insertion of osseointegrated implants. Objective: To evaluate the effects of demineralized dentin and fibrin-rich plasma graft on alveolar preservation. Material and methods: Clinical case performed at the USC Oral Surgery Teaching Unit, in a Young male patient, in whom the extraction of a canine included at the palatal level and simultaneous placement of an immediate post-extraction implant had been planned. However, the wide ostectomy required to extract the canine, the large size of the eruptive capsule that surrounded the included tooth, and the scarce bone availability, made it advisable to delay the insertion of the implant to a second surgical time. Conclusions: The demineralized dentin graft is considered a new therapeutic option in those clinical cases in which it is required to obtain a significant amount of graft. With the limited studies that currently have, we can affirm that the autologous dentin graft does not provoke an immune reaction, so its biological and functional incorporation is fast, effective and predictable, Introdución: A extracción dun dente xera cambios morfolóxicos e fisiolóxicos a nivel alveolar. As técnicas de preservación alveolar teñen como principal obxectivo limitar devanditos cambios tras a exodoncia, coa finalidade de que, unha vez finalizado o proceso de cicatrización, dispóñase dun volume óseo que facilite unha rehabilitación protésica o máis estética e funcional posible tras a inserción dos implantes osteointegrados. Obxectivos: Avaliar os efectos do enxerto de dentina desmineralizada e plasma rico en fibrina na preservación alveolar. Material e métodos: Caso clínico realizado na Unidade Docente de Cirurxía Oral da USC, nun paciente home, no que inicialmente se lle planificou a exodoncia dun canino incluído a nivel palatino e colocación simultánea dun implante inmediato posextracción. Con todo, a ampla ostectomía necesaria para a extracción do canino, o gran tamaño da cápsula eruptiva que rodeaba ao dente incluído e a escasa dispoñibilidade ósea, aconsellaron demorar a inserción do implante a un segundo tempo cirúrxico Conclusión: O enxerto de dentina desmineralizada é considerada unha nova opción terapéutica ante aqueles casos clínicos nos que se require obter unha importante cantidade de enxerto. Cos estudos que dispoñemos na actualidade, podemos afirmar que o enxerto de dentina autóloga non provoca reaccións desfavorables, polo que a súa integración biolóxica e funcional é rápida, efectiva e predicible

This paper includes the available information of the Blackspot seabream (Pagellus bogaraveo) Spanish “voracera” target fishery of the Strait of Gibraltar. The documents presented in previous years were updated with the 2020 information: data about landings, fishing effort, CPUEs and landings length frequencies are presented to its discussion within the 2021 WGDEEP.

Overexploitation and climate change are increasingly causing unanticipated changes in marine ecosystems such as higher variability in fish recruitment or shifts in species dominance and distribution that alter the productivity of fish stocks. This study analyses how external and internal drivers influence population dynamics of hake (Merluccius merluccius), white anglerfish (Lophius piscatorius), four-spot megrim (Lepidorhombus boscii), and horse mackerel (Trachurus trachurus) of Iberian Peninsula waters of the Northeast Atlantic across different spatiotemporal scales. Available spawning stock biomass and recruitment have been used as biological data, whereas fishing mortality, demographic data as well as climatic and oceanographic data have been used as drivers. The obtained results indicate that population dynamics of these species are mainly driven by oceanographic variability at regional scale along with fishing pressure and demographic factors, while the impact of large-scale climate indices was minimal. The identified variables represent relevant oceanographic regional processes candidate to be potentially integrated into the stock assessment models and management procedures of these important fishery resources

Understanding the processes that influence octopus abundance is important in order to manage the fishing grounds and offer advice on the exploitation of this important resource. Fluctuations in abundance of exploited stocks may be due to a great variety of factors. However, in short-lived animals such as cephalopods, in which abundance depends on strength of the recruitment, it is well known that population abundance is highly influenced by the environmental conditions. In this study we investigated the relationship between octopus (Octopus vulgaris) catches from the fishery located in the area off the Gulf of Cadiz (Spanish South Atlantic Region) and several hydrographic and oceanographic parameters such as sea surface temperature, surface chlorophyll-a, inorganic surface turbidity and climatic indicators such as the NAO index, rain, WeMoi Index, AMO index and or Guadalquivir River discharges. In addition, a recruitment index was obtained from fishery-independent surveys, which was also used to investigate its effect on annual catches. Results revealed that abundance of octopus showed a significant negative relationship with rain in the previous year as well as a positive effect of the recruitment index. We have obtained a model using the rain and the recruit index to forecast the catches. This model explained a high percentage of variation in annual catches and was used to forecast the next year’s catch providing results within the expected confidence intervals. This represents a potentially useful tool to guide fishery managers since no assessment of the species is currently conducted in the area.

Long fisheries time series allow the review of baselines and inform our knowledge of past events that have conditioned the recent history of the stocks. In this study, we investigated trends in fisheries landings data for the most representative Atlantic and Mediterranean demersal fisheries off the Spanish Iberian Peninsula and the Balearic Islands (1933–1986). The aim was to analyse the evolution of demersal species exploitation and detect changes in landings and fishing tactics. Ten species were selected, which included teleosts, crustaceans, and cephalopods. Results indicated a decrease in Landings Per Unit of Capacity (LPUC) in six of the species examined. While in the Atlantic the process of substitution or incorporation of new species to the fisheries occurs progressively, in the Mediterranean this incorporation occurs simultaneously for many of the species. Four main fishing tactics (landing pattern obtained from the classification analysis of landings per species) were identified. Geographically nearby and connected regions developed similar fishing tactics to each other, and also changed over time. While the fleets from isolated regions were more specialized, and only carrying out one fishing tactic during the study period. Improvements in LPUC with the implementation of new technology and legislative and management measures were not observed.

To assess the likely economic outcomes to fishing fleets of the Landing Obligation (LO), bioeconomic models covering seven European fisheries, ranging from the North East Atlantic to the Mediterranean, have been applied to estimate the economic performance of fleets before and after implementing the LO. It is shown that for most of the analysed fisheries, their economic outcome will be negatively affected in the long term by the LO, when compared to the expected outcome with no LO. Efficient mitigation strategies (exemptions, quota uplifts, improved selectivity, effort reallocation and others) may, for some of the analysed fisheries, reduce the negative economic effect of the LO. Moreover, the possibility to trade quotas, both nationally and internationally, may also reduce the economic losses caused by the LO. However, even with mitigation strategies and/or quota trade in place, most of the analysed fisheries are worse off under the LO than what could be expected if the LO was not implemented

The demersal fisheries in the Mediterranean Sea are heavily overfished but the landing obligation will not help to reach MSY because it will not decrease fishing mortality. The new proposal of the Commission introduces total allowable effort as a new way to regulate Western Mediterranean demersal fisheries by significantly reducing fishing time. However, this new management measure must be complemented with increased gear selectivity, implementation of closed areas and local co-management plans. Different approaches to reduce fishing mortality may have different socio-economic impact.

According to their main life history traits, organisms can be arranged in a continuum from fast (species with small body size, short lifespan and high fecundity) to slow (species with opposite characteristics). Life history determines the responses of organisms to natural and anthropogenic factors, as slow species are expected to be more sensitive than fast species to perturbations. Owing to their contrasting traits, cephalopods and elasmobranchs are typical examples of fast and slow strategies, respectively. We investigated the responses of these two contrasting strategies to fishing exploitation and environmental conditions (temperature, productivity and depth) using generalized additive models. Our results confirmed the foreseen contrasting responses of cephalopods and elasmobranchs to natural (environment) and anthropogenic (harvesting) influences. Even though a priori foreseen, we did expect neither the clear-cut differential responses between groups nor the homogeneous sensitivity to the same factors within the two taxonomic groups. Apart from depth, which affected both groups equally, cephalopods and elasmobranchs were exclusively affected by environmental conditions and fishing exploitation, respectively. Owing to its short, annual cycle, cephalopods do not have overlapping generations and consequently lack the buffering effects conferred by different age classes observed in multi-aged species such as elasmobranchs. We suggest that cephalopods are sensitive to short-term perturbations, such as seasonal environmental changes, because they lack this buffering effect but they are in turn not influenced by continuous, long-term moderate disturbances such as fishing because of its high population growth and turnover. The contrary would apply to elasmobranchs, whose multi-aged population structure would buffer the seasonal environmental effects, but they would display strong responses to uninterrupted harvesting due to its low population resilience. Besides provid

Resolving drivers of spatial synchrony in marine species is fundamental for the management and conservation of deep-sea ecosystems. Here we examine an 11-year data set of monthly catches per unit of effort (CPUE) of the red-shrimp Aristeus antennatus. These data comprise 16 locations of two population subunits in the Western Mediterranean, the Catalan coast and the Balearic archipelago. The analysis of their seasonal covariation and its space-time structure showed small-scale geographical segregation of locations linked with the seasonal fluctuations of CPUE. Results further revealed that seasonal synchrony dominates at short spatial scales (ca. 50 km), while asynchrony prevails are broader spatial scales (ca. 200-300 km). This spatial pattern, however, varied over the period examined, although it was specific for each population subunit suggesting contrasting drivers of seasonal synchrony. The Balearic Islands, a patchier population subunit, displayed a seasonal synchrony pattern mainly dependent on biological and oceanographic processes at local scales. By contrast, in the Catalan coast, the pattern appeared related with regional-scale climate, which triggers spatial differences in the phenology of primary producers and the timing of food advection to the seabed. These cascading processes depicted by our investigation shed light on underlying mechanisms shaping the temporal synchrony of broadly distributed deep-sea populations.