Age validation of the European Anchovy (Engraulis encrasicolus Linnaeus, 1758) in the Central-Southern Tyrrhenian Sea (West Mediterranean Sea)

The validation of growth of the European Anchovy (Engraulis encrasicolus Linnaeus, 1758) presents several gaps in the Mediterranean Sea, despite its growth has been widely studied using different methods. The uncertainty in estimating the European Anchovy age by otolith interpretation is linked to (i) the identification of the first growth ring; (ii) the presence of false increments; (iii) discrepancies in the applied age scheme (e.g. theoretical birthdate); and (iv) the progressive compactness of the last annuli in older specimens. The present study was conducted on specimens caught in Central-southern Tyrrhenian Sea between 2012 and 2016. The analyses of the otolith edge type and the marginal increment analysis allowed to describe the annuli deposition pattern, with the opaque ring deposited from June to September, and the translucent ring from October to May. The growth pattern inferred from the European Anchovy otoliths was either corroborated or indirectly validated by the agreement between the length–frequency results and the otolith age estimation. No significant differences were found between the von Bertalanffy growth curves calculated by otolith interpretation (back-calculation and direct otolith reading) and the LFDA. These outcomes resulted highly relevant for species, such as small pelagic fish, for which the direct validation methods (e.g. mark-recapture, captivity, radiochemical) are particularly difficult to implement

Assessing stakeholder's experience and sensitivity on key issues for the economic growth of organic aquaculture production

Participatory management is widely recognised as a working method of paramount importance, based on the principles of knowledge sharing, accountability and legitimacy. Hence, it is broadly considered suitable for addressing issues related to the sustainable development of the seafood industry, and specifically, of the aquaculture system. A survey focused on the current EU regulatory framework was carried out to elicit stakeholders’ preferences, knowledge and experience on key issues for the development of organic aquaculture, supported by science-based regulations. The survey was completed by 65 stakeholders belonging to several categories, and it was supported by the implementation of the Analytic Hierarchy Process method. Stakeholders’ preferences were elicited on organic production methods and control systems, the quality of the environment and organic products, fish health and welfare. The views expressed by the participants revealed both competence and awareness, despite the complexity of the subject. Several ideas and useful suggestions emerged regarding unresolved technical issues. In addition, the need for a targeted communication strategy on the quality of organic aquaculture products and the necessity of fostering European/national programs to support the production and marketing of organic aquaculture products were highlighted

Fourth workshop on optimization of biological sampling (WKBIOPTIM4; Outputs from 2021 meeting)

The workshop on optimization of biological sampling (WKBIOPTIM4) was the fourth meeting of a series of workshops aiming at collaborating on fish sampling optimisation processes across ICES Member States. It aimed primarily at providing an update on the development of the different simulation approaches presented and tested during the third workshop (WKBIOPTIM3), at working on shared indicators across these tools, and at creating an R package for end users. Multiple simulation approaches were discussed during the first three workshops, developed as R scripts, and also contributed by separate projects (STREAM and FishPi2). The focus of WKPBIOPTIM4 was on the following tools: [1] two STREAM tools, BioSimTool and SDTool; [2] the Fishpi4WKBIOPTIM package; [3] SampleReferenceLevel (ADV); and [4] SampleOptim. While there is no current follow-up on the FishPi2 project that the group was made aware of, progress has been made on the other approaches aforementioned: a project called STREAMline is expected to build upon the outputs of STREAM; SampleOptim is being further developed and applied in Portugal; and the SampleReferenceLevel (ADV) approach was published (Wischnewski et al., 2020). Over the week of the workshop, one subgroup focused on the development of an R-package for indicators, with the objective of making the outputs of simulations comparable across approaches and facilitating interpretation for end-users through documentation. A second subgroup worked on testing the comparativeness of these tools in order to feed into this process of comparison and interpretation across tools. Additionally, the effect of simulating sampling with and without replacement on model outputs was discussed and some investigation was conducted in two case studies: one using the SampleOptim tool with blue whiting data and the other using data from a simulated population. Finally, a third subgroup focused on a significant upcoming change which will affect the data input of the tools being developed, i.e. the move from the current Regional Database (RDB) to the new Regional Database and Estimation System (RDBES). Future work on the WKBIOPTIM tools should include continuing development and testing, the R-package development, and adaptations to accommodate the sampling schemes from the different RDBES hierarchies

Distribución espacial a gran escala de la megafauna de aguas profundas en fondos arrastrables del Mediterráneo

The large-scale distribution pattern of megafauna communities along the Mediterranean middle slope was explored. The study was conducted between 500 and 800 m depth where deep-water fishery occurs. Although community studies carried out deeper than 500 m are partly available for some geographic areas, few large-scale comparative studies have been carried out. Within the framework of the MEDITS survey programme, we compared the megafauna community structure in ten geographical sub-areas (GSAs) along the Mediterranean coasts. Additionally, the spatial distribution of fishing was analysed using vessel monitoring by satellite information. Overall, the community showed a significant difference between sub-areas, with a decreasing eastward pattern in abundance and biomass. Longitude was the main factor explaining variation among sub-areas (by generalized additive models). However, we found a region which did not follow the general pattern. GSA 6 (northern Spain) showed significantly lower abundance and a different composition structure to the adjacent areas. The decrease in community descriptors (i.e. abundance and biomass) in this area is probably a symptom of population changes induced by intense fishery exploitation. Overall, a combination of environmental variables and human-induced impacts appears to influence the bentho-pelagic communities along the slope areas of the Mediterranean.En este estudio se describe la estructura y patrones de distribución de la comunidad de megafauna que habita en el margen continental medio a lo largo del Mediterráneo. El estudio se realizó entre los 500 y 800 m, coincidiendo espacialmente con las pesquerías de profundidad. A pesar de que se conoce parcialmente la estructura de las comunidades que habitan por debajo de 500 m, existe la necesidad de estudiar estas comunidades a una escala espacial más amplia. Dentro del marco del proyecto internacional MEDITS, se comparó la estructura de las comunidades en diez sub-áreas geográficas (GSAs) a lo largo de las costas mediterráneas. Además se analizó la distribución espacial del esfuerzo pesquero utilizando la información de los datos de seguimiento de buques. En general los resultados mostraron diferencias significativas entre subáreas mostrando un patrón decreciente en los valores de biomasa hacia el este, siendo la longitud el principal factor explicativo del modelo de distribución (GAMs). Sin embargo, encontramos una subárea que no seguía el patrón general, la GSA6 (norte de España). La GSA6 mostró una biomasa y estructura de la comunidad diferente a las áreas adyacentes. La disminución de la biomasa en esta área parece ser un síntoma de los cambios poblaciones causados por la elevada intensidad de pesca en la zona. Los resultados sugieren que la distribución y estructura de las comunidades bento-pelágicas parecen estar moduladas por la combinación de las variables ambientales y los impactos producidos por la actividad humana

SEAwise report on social indicators to evaluate the social impacts of management strategies

The SEAwise project works to deliver a fully operational tool that will allow fishers, managers, and policy makers to easily apply Ecosystem Based Fisheries Management (EBFM) to their own fisheries. Human behaviour changes in response to management measures and understanding how management influences human behaviour is key to this aim. Further, the resulting social impact of management measures or other changes affecting the ecosystem are key to implementing EBFM for the full social-ecological system. This report demonstrates the topics necessary to cover in a comprehensive analysis at different, especially higher scale levels in the EU. For ecosystem based fisheries management, it is crucial to understand that fishers respond to management measures with their behaviour and that management measures impact different fleets and communities in different ways. The better we are at anticipate this before measures are taken, the better unintended consequences can be prevented. Modelling of fleet behaviour with adequate behavioural sub-models and linked fleet-fishing communities allow for such foresight which will help improve the effectiveness of policy while collecting and incorporating social data on stakeholder perspectives enhances the legitimacy and acceptance of fisheries policy and management processes and allows for the development of policies that are equitable and inclusive.This deliverable demonstrates how these issues can be approached to derive a better understanding of social dynamics of fisheries and the way to full social impact assessments providing information about social and cultural factors that need to be considered in management decisions. We investigated the following topics in a case-by-case approach:ways to improve understanding of fisheries behaviour,ways to identify fishing communities and connecting them to fleets.how community profiles can be developedhow to make use of other social census data and link that with data on fleets and coastal and fisheries communities to develop social vulnerability indices, fishing engagement and reliance of coastal communities indices.how social impact can change and how people are affected by asking people via different methodsBy addressing these topics, this report contributes to a better understanding of how society is and can be impacted by fisheries

Análisis exploratorio de los datos de determinación de edad de Mullus barbatus en el Mediterráneo

The uncertainty in age estimation by otolith reading may be at the root of the large variability in red mullet (Mullus barbatus) growth models in the Mediterranean. In the MEDITS survey, red mullet age data are produced following the same sampling protocol and otolith reading methodology. However, ageing is assigned using different interpretation schemes, including variations in theoretical birthdate and number of false rings considered, in addition to differences in the experience level of readers. The present work analysed the influence of these variations and the geographical location of sampling on red mullet ageing using a multivariate approach (principal component analysis). Reader experience was the most important parameter correlated with the variability. The number of rings considered false showed a significant effect on the variability in the first age groups but had less influence on the older ones. The effect of the theoretical birthdate was low in all age groups. Geographical location had a significant influence, with longitude showing greater effects than latitude. In light of these results, workshops, exchanges and the adoption of a common ageing protocol based on age validation studies are considered fundamental tools for improving precision in red mullet ageing.La incertidumbre en la estimación de la edad mediante la lectura de otolitos puede ser la principal causa detrás de la gran variabilidad existente en los modelos de crecimiento del salmonete (Mullus barbatus) en el Mediterráneo. En la campaña MEDITS, los datos de edad del salmonete se generan siguiendo el mismo protocolo de muestreo y metodología de lectura de otolitos, aunque la asignación de la edad se lleva a cabo usando distintos esquemas para la interpretación de las lecturas, incluyendo variaciones en la fecha teórica de nacimiento y en el número de anillos considerados falsos, además de las diferencias existentes en cuanto al nivel de experiencia de los lectores. En este trabajo, la influencia de las variaciones en los esquemas de interpretación, el nivel de experiencia de los lectores, y la localización geográfica de las muestras, sobre la determinación de la edad en el salmonete se analiza mediante una aproximación multivariante (Análisis de Componentes Principales). La experiencia de los lectores fue el parámetro más correlacionado con la variabilidad. El número de anillos considerados falsos mostró un efecto significativo sobre la variabilidad de los primeros grupos de edad, mientras que su influencia sobre los más viejos fue menor. El efecto de la fecha teórica de nacimiento tuvo poca importancia en todos los grupos de edad. La localización geográfica tuvo una influencia significativa, con la longitud mostrando mayores efectos que la latitud. Teniendo en cuenta estos resultados, los grupos de trabajo e intercambios de otolitos así como la adopción de un protocolo de asignación de edad común basado en estudios de validación de edad, se consideran herramientas fundamentales para mejorar la precisión en la determinación de la edad del salmonete

Working Group on Biological Sampling Optimization (WGBIOPTIM)

86 páginasThe Working Group on Optimization of Biological Sampling (WGBIOPTIM) aims to develop and provide guidance on R-tools applications for evaluating strategies to optimize biological sampling programs under data collection national programs. The primary purpose of sampling optimization is to ensure that time and costs invested in sampling are effectively justified in terms of the quality of information ultimately provided to stock assessment end-users. During the 2023 and 2024 working group meetings, developers presented descriptions of the R-tools optimization methodologies and conducted specific hands-on sessions. These R-tools were made available on the WGBIOPTIM GitHub repository for exploration and testing during and after the meetings (Term of Reference (ToR) a, ToR b and ToR f). Participants conducted several case studies to test the different R-tools (ADV, SDTool, BioSim and SampleOptim). Additionally, the group initiated discussions on survey data to identify current needs for sampling optimization. Two case studies were identified by the participants for applying the available tools, specifically focusing on SampleOptim and ADV for age data optimization and number of length measurements. The group reviewed existing open-access simulation tools specifically designed for survey data. Furthermore, work began on R-code conversion functions from the RDBES format to the RDB from different hierarchies (ToR e). These conversion functions will be included in the BIOPTIMcore R-package, along with the indicators functions from the various optimization R-tools (ToR c). The WGBIOPTIM GitHub project webpage was updated to outline the next steps for each subgroup and their associated ToR, with a defined time schedule (ToR f). To see the full WGBIOPTIM Resolution and all the ToR defined, see Annex 2.Peer reviewe

SEAwise Report on the Key Social and Economic Aspects of Regional Fisheries

Fishing is a human activity with various social and economic implications. In most countries, those implications are key factors to consider when deciding on specific management strategies. In this report, the fisheries management strategies implemented in the different European marine regions are reviewed, and relevant indicators, models and tools that can be used to predict the effectiveness of these strategies, from a social and economic point of view are identified. The objective was to identify the critical social and economic aspects of fisheries, relevant social and economic indicators, and regionally-relevant management measures to be considered in the evaluations of different management strategies later in the project.The scoping consultations and systematic reviews identified a long list of potentially relevant key social and economic aspects and management measures. Among these, the most frequently mentioned items identified in scoping with stakeholders were windfarms, employment/jobs, MPAs, food supply, small-scale fisheries, local communities and pollution. The systematic review identified landings (volume or value), effort (days at sea), fuel costs, number of vessels, profit, aspects of costs, economic performance, sustainability-resilience, compliance and capacity as frequently occurring topics. The fisheries management policies most frequently mentioned were effort control, landing obligation, Individual Transferable Quota (ITQ), MPAs and TAC. Among the papers analyzed, more than 30%, concerned the Mediterranean region, followed by Western Waters, the North Sea and the Baltic Sea, indicating a higher contribution of Mediterranean studies to the conclusions.Aspects identified frequently in both scoping and in systematic reviews included MPAs and small-scale fisheries, which were all identified in both methods as frequently occurring. However, there were also aspects which appeared to be represented differently in the evaluations (e.g. employment and local communities) indicating discrepancies between the available knowledge and that sought by the end users

The Seascape of Demersal Fish Nursery Areas in the North Mediterranean Sea, a First Step Towards the Implementation of Spatial Planning for Trawl Fisheries

The identification of nursery grounds and other essential fish habitats of exploited stocks is a key requirement for the development of spatial conservation planning aimed at reducing the adverse impact of fishing on the exploited populations and ecosystems. The reduction in juvenile mortality is particularly relevant in the Mediterranean and is considered as one of the main prerequisites for the future sustainability of trawl fisheries. The distribution of nursery areas of 11 important commercial species of demersal fish and shellfish was analysed in the European Union Mediterranean waters using time series of bottom trawl survey data with the aim of identifying the most persistent recruitment areas. A high interspecific spatial overlap between nursery areas was mainly found along the shelf break of many different sectors of the Northern Mediterranean indicating a high potential for the implementation of conservation measures. Overlap of the nursery grounds with existing spatial fisheries management measures and trawl fisheries restricted areas was also investigated. Spatial analyses revealed considerable variation depending on species and associated habitat/depth preferences with increased protection seen in coastal nurseries and minimal protection seen for deeper nurseries (e.g. Parapenaeus longirostris 6%). This is partly attributed to existing environmental policy instruments (e.g. Habitats Directive and Mediterranean Regulation EC 1967/2006) aiming at minimising impacts on coastal priority habitats such as seagrass, coralligenous and maerl beds. The new knowledge on the distribution and persistence of demersal nurseries provided in this study can support the application of spatial conservation measures, such as the designation of no-take Marine Protected Areas in EU Mediterranean waters and their inclusion in a conservation network. The establishment of no-take zones will be consistent with the objectives of the Common Fisheries Policy applying the ecosystem approach to fisheries management and with the requirements of the Marine Strategy Framework Directive to maintain or achieve seafloor integrity and good environmental status.Versión del editor4,411