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16 pages, 5 tables, 6 figures.-- This is an Open Access article distributed under the terms of the Creative Commons Attribution License, Knowledge of stock structure is a priority for effective assessment of commercially-fished cephalopods. Loligo forbesii squid are thought to migrate inshore for breeding and offshore for feeding and long-range movements are implied from past studies showing genetic homogeneity in the entire neritic population. Only offshore populations (Faroe and Rockall Bank) were considered distinct. The present study applied mitchondrial and microsatellite markers (nine loci) to samples from Rockall Bank, north Scotland, North Sea, various shelf locations in Ireland, English Channel, northern Bay of Biscay, north Spain, and Bay of Cadiz. No statistically significant genetic sub-structure was found, although some non-significant trends involving Rockall were seen using microsatellite markers. Differences in L. forbesii statolith shape were apparent at a subset of locations, with most locations showing pairwise differences and statoliths from north Ireland being highly distinct. This suggests that (i) statolith shape is highly sensitive to local conditions and (ii) L. forbesii forms distinguishable groups (based on shape statistics), maintaining these groups over sufficiently long periods for local conditions to affect the shape of the statolith. Overall evidence suggests that L. forbesii forms separable (ecological) groups over short timescales with a semi-isolated breeding group at Rockall whose distinctiveness varies over time, This research comes from the Cephs & Chefs project (https://www.cephsandchefs.com/) and was funded by the European Regional Development Fund through the Interreg Atlantic Area Programme grant number EAPA_282/2016

Rapports Scientifiques du CIEM. Volume 5, nº 1 WGCEPH worked on six Terms of Reference. These involved reporting on the status of stocks; reviewing advances in stock identification, assessment for fisheries management and for the Ma- rine Strategy Framework Directive (MSFD), including some exploratory stock assessments; re- viewing impacts of human activities on cephalopods; developing identification guides and rec- ommendations for fishery data collection; describing the value chain and evaluating market driv- ers; and reviewing advances in research on environmental tolerance of cephalopods. ToR A is supported by an annual data call for fishery and survey data. During 2019–2021, com- pared to 1990–2020, cuttlefish remained the most important cephalopod group in terms of weight landed along the European North Atlantic coast, while loliginid squid overtook octopus as the second most important group. Short-finned squid remained the least important group in land- ings although their relative importance was almost double in 2019–2022 compared to 1992–2020. Total cephalopod landings have been fairly stable since 1992. Cuttlefish landings are towards the low end of the recent range, part of a general downward trend since 2004. Loliginid squid landings in 2019 were close to the maximum seen during the last 20 years but totals for 2020 and 2021 were lower. Annual ommastrephid squid landings are more variable than those of the other two groups and close to the maximum seen during 1992– 2021. Octopod landings have generally declined since 2002 but the amount landed in 2021 was higher than in the previous four years. Under ToR B we illustrate that the combination of genetic analysis and statolith shape analysis is a promising method to provide some stock structure information for L. forbsii. With the sum- mary of cephalopod assessments, we could illustrate that many cephalopod species could al- ready be included into the MSFD. We further provide material from two reviews in preparation, covering stock assessment methods and challenges faced for cephalopod fisheries management. Finally, we summarise trends in abundance indices, noting evidence of recent declines in cuttle- fish and some octopuses of the genus Eledone. Under ToR C, we describe progress on the reviews of (i) anthropogenic impacts on cephalopods and (ii) life history and ecology. In relation to life history, new information on Eledone cirrhosa from Portugal is included. Under ToR D we provide an update on identification guides, discuss best practice in fishery data collection in relation to maturity determination and sampling intensity for fishery monitoring. Among others, we recommend i) to include the sampling of cephalopods in any fishery that (a) targets cephalopods, (b) targets both cephalopods and demersal fishes or (c) takes cephalopods as an important bycatch, ii) Size-distribution sampling, iii) the use of standardized sampling pro- tocols, iv) an increased sampling effort in cephalopod. Work under ToR E on value chains and market drivers, in conjunction with the Cephs & Chefs INTERREG project, has resulted in two papers being submitted. Abstracts of these are in the report. Finally, progress under ToR F on environmental tolerance limits of cephalopods and climate en- velope models is discussed, noting the need to continue this work during the next cycle. info:eu-repo/semantics/publishedVersion

Cephalopod International Advisory Council Conference, Cephalopods in the Anthropocene: Multiple Challenges in a Changing Ocean, April 2-8, 2022, Sesimbra, Portugal, Because cephalopods in the Northeast Atlantic have long been considered as minor commercial resources data acquisition is often scanty and fisheries scientists are tempted to apply DLS (Data Limited Stocks) methods to these stocks. However, progress made in the understanding of cephalopod population dynamics or of their role in the ecosystem reveals that cephalopod population assessment is data demanding. Each progress, from the adaptation of Leslie-DeLury methods to its generalized version required data at a finer temporal resolution than in most fin fish stock assessments. The difficulty and huge effort in obtaining finer scale information on a routine basis has led to some approaches being abandoned (like age-based methods). The ecosystem approach also requires a better integration of cephalopods in trophic models and accurate diet data. The challenges that we are facing with possible spatial distribution shifts or the need to understand the consequences of local dynamic fishing pressure are not likely detected by DLS tools and will also require data at a fine spatial and temporal scale. Examples such as "the September 2017 cuttlefish rush in the Southwest of England" or the interaction between small-scale and large-scale fisheries, underline the difficulties in estimating the level of fishing mortality in short-lived migrating populations. Recent diagnostics about large management units assessed on an annual basis do not confirm fishers’ observations

Changing oceans impact the whole marine ecosystem in different ways. For example, rising ocean temperatures can affect the presence / absence of species, especially when local environmental conditions exceed individual species’ physiological tolerances. Accordingly, climate change has caused shifts in distribution and expansions for various cephalopods worldwide. Cephalopods play an important role in the ecosystem, especially in food webs. Consequently, spatial distribution shifts might help explain observed ecosystem changes. Therefore, maps for cephalopod distributions need to be reviewed and updated. Meanwhile, information on the associated environmental conditions will permit future occurrence of cephalopods to be modelled, which is interesting from a fishery and ecological perspective. Some information about physiological tolerances of cephalopods are known from laboratory studies and aquaculture experience, as well as from field observations. Laboratory data are often based on narrow ranges, depending on the experimental design, and can therefore provide only a limited understanding of physiological tolerances. On the other hand, field observations are also limited due to the spatial and temporal limitations of surveys, but these might provide a more realistic picture of natural tolerances. Here, we use the ICES Datras dataset to, first, describe the current distribution of cephalopods associated with the European shelf and, second, advance the knowledge regarding environmental ranges of the various species included in the analysis by combining occurrence data with in-situ oceanographic data. An additional literature review will provide information about the different environmental requirements of various life stages. The results allow us to increase the knowledge of physiological preferences of various cephalopod species within the North-East Atlantic Ocean. Finally, we will discuss and present potential future trends in cephalopod occurrence within the NE Atlantic. In order to further strengthen our knowledge of physiological tolerances of various cephalopod species more data on life history and life stages is needed to develop a more advanced mechanistic model. info:eu-repo/semantics/publishedVersion

World Fisheries Congress 2021 (WFC), 20-24 September

Sem resumo disponível. INTERREG Atlantic Area (EAPA 282/2016) published

The lack of management leaves fishery resources vulnerable to increases in fishing pressure.Although some cephalopods are of commercial importance, most of Northeast Atlantic stocks are non-quota species(no catch or effort limits in large-scale fisheries and only some harvest control rules at the local scale in inshore fisheries). Cephalopods are short-lived, fast growing species, with highly plastic lifehistory characteristics and wide year to year variation in abundance linked to environmental variation. This had contributedto prevent the use of classical stock assessments methods and monitoringsuch species is also data-demanding with some of the largest EU cephalopod fisheriesbeing not includein fishery data collection protocols.These factors have led the cephalopods to be classified under the ICES category 3 data limited stocks.Severalstock assessment exercises were already carried out in European cephalopods but the wide variety of models tested to tackle distinctive features of different species makes it difficult to compare results. The progress on assessment methods for short-lived data limited stocks that are cephalopods and estimation of biological and MSY proxy reference points, focused on the application of the model SPiCT for stochastic production in continuous time (Pedersen and Berg, 2017).This model allowed the abundance time series for several Northeast Atlantic cephalopod stocksto be fit, including cuttlefish and squids(Loliginidae and Ommastrephidae) and octopuses (Octopodidae). The different assessed stocks were distributedfrom Scottish to Spanish and Portuguese fishing grounds. All models have beenfitted with the R package SPiCT, the homogeneous protocol allowingcomparisons between outputs. In the presentedcases, the model converged and the exercise provided useful preliminary diagnostics, allowing long-term trends in productivity to be considered reasonable(only the Rockall6.b exercise for Loligospp.showed unreliable outputs). Results for the cuttlefish indicated a rather good condition of the stock since 2008, relative fishing mortality interestingly following the fishing efforts trends on the available time-series. For several Loliginidstocks, results allowed statements to be made about whether biomass and fishing effort were above or below MSY reference values. However, especiallyforOmmastrephidaeand Octopodidae, confidence intervals were still huge and it was generally not possible to be sure whether biomass and fishing effort were above or below reference levels.Also the convergence was sometimes obtained after a set of input parametrization on the priors.The possible causes for this uncertaintyare discussed andwill have to be further exploredeven if some refinements to the approach taken arealreadyproposed for future work. non-peer-reviewed

Poster.-- ICES Annual Science Conference 2021, 6–10 September, Virtual conference, Visual analysis of prey remains in squid stomachs underline that Loliginid squid eat predominantly teleost fish. However, a significant proportion of these preys cannot be identified to the species and are presented as "undetermined teleost fish, This poster is based on work undertaken under the auspices of ICES WGCEPH and the Cephs & Chefs project (EAPA_282/2016, Atlantic INTERREG)

4th International Congress on Applied Ichthyology, Oceanography and Aquatic Environment. Hydromedit, Virtual, 4-6 November 2021

International audience; The presence of shells of the Atlantic rangia, Rangia cuneata, a brackish-water species native from the Gulf of Mexico also known as gulf wedge clam, was reported in 2017 on the French coasts of the English Channel, in the waterway that connects Caen to the sea. However, no information was available on whether a population of this alien species had successfully established in the region. Here, only empty shells-except for one live individual-were sampled in that waterway, and the sampling was shifted to the nearby marina of Ouistreham, where water is mesohaline (6.89 ± SD 0.06 PSU). In spring 2017, the mean density in the marina reached 110.45 ± 86.08 ind m-2 , largely dominating the benthos community. The population was mostly composed of fairly large individuals, with no young-of-the-year found inside the marina. The modal values of the size frequency distribution ranged between 35 and 40 mm shell length. The growth patterns determined from the annual rings suggest a maximum lifespan of eight completed years. Following the assumption that colonization occurred at the larval stage, as in other European countries, this population may have established in 2009, i.e. only four years after its first detection in Europe, in the Antwerp harbour. The specimens collected are the largest recorded in European waters, suggesting a highly suitable environment for the species in the region. Given the invasive potential of Atlantic rangia within the last decade, a close monitoring of this population and of the spread of the species in French and European waters appears necessary to determine its impacts on these ecosystems.

info:eu-repo/semantics/publishedVersion

Le niveau trophique moyen (MTL) est couramment utilisé pour caractériser la structure des écosystèmes marins exploités et évaluer leur état de santé. Afin d’atteindre une description plus complète du fonctionnement des écosystèmes, il peut être complété par les indices ENA (Ecological Network Analysis). Ces derniers caractérisent les propriétés émergentes des écosystèmes, reliées par les théories écologiques, à stabilité et la maturité des systèmes. Il existe un grand nombre d’indices ENA, comme le recyclage, l’efficacité de transfert trophique ou encore le rapport détritivorie / herbivorie. Pour étudier le cumul de l’effet du changement climatique avec celui attendu de l’implantation d’éoliennes offshore en baie de Seine, un modèle Ecospace, composé de cellules d’un mille marin de côté, a été créé, du trait de côte jusqu’à la limite de la zone économique exclusive française. Le modèle est utilisé pour simuler l’effet du réchauffement climatique par l’intégration de résultats de modèles de niches écologiques, et l’effet du parc éolien offshore par l’effet réserve qu’il induit. Nous pouvons ainsi calculer des cartes d’indices ENA afin de comprendre les conséquences du cumul d’impacts sur l’écosystème de la baie de Seine. Même si la réponse varie en fonction de l’échelle spatiale considérée, l’effet du changement climatique domine, engendrant une baisse importante de la biomasse des 44 espèces considérées dont 27 espèces de poissons. Les indices ENA les plus sensibles à l’effet changement climatique sont le rapport D/H et l’efficacité de transfert trophique, ce dernier et le recyclage étant les plus sensibles à l’effet réserve. Le modèle permet ainsi de comparer l’évolution du service d’approvisionnement halieutique avec les propriétés émergentes, de l’écosystème.

Les études environnementales réalisées en amont des projets éoliens offshores permettent de mettre en évidence leurs impacts potentiels, en s’attachant à considérer la sensibilité aux perturbations de chacun des compartiments écologiques (benthos, poissons, oiseaux, mammifères marins etc), de façon fractionnée. Le projet TROPHIK porte sur l’impact du futur parc éolien au large de Courseulles-sur-mer, cumulé avec ceux des changements climatiques et de la pêche. Avec ce projet nous avons développé une vue d’ensemble, intégrée, par la mise en place d’outils de modélisation, complémentaires aux approches utilisées lors des études d’impact. Nous avons considéré le réseau trophique et le socio-écosystème dans son ensemble, en combinant différents modèles. La modélisation de niches écologiques a permis de simuler le probable déplacement des espèces de la Manche selon les scénarios du GIEC (Groupe d'experts intergouvernemental sur l'évolution du climat). L’analyse inverse linéaire (LIM-MCMC) a permis une modélisation en 0D du site du parc. Les scénarios ont pu combiner les effets du changement climatique et les effets récifs et réserve associés à la construction du parc, tout en appliquant les indices ENA (analyse des réseaux écologiques) avec une quantification de leur incertitude. Le modèle Ecopath-Ecosim-Ecospace, a permis de modéliser le réseau trophique en 2D sur toute la baie de Seine étendue jusqu’à la frontière franco-britannique, et de réaliser différents scénarios ayant pour sorties des cartes d’indices ENA. Enfin, la modélisation qualitative en digraphes orientés des socio-écosystèmes a permis de faire un pas vers une intégration équilibrée des réseaux d’interactions entre acteurs et espèces. Cette combinaison d’approches constitue un socle, transférable à toute situation similaire d’impacts en mer, qui sera présenté avec différentes recommandations tirées du projet.

ICES Annual Science Conference, 9-12 September 2019, Gothenburg, Sweden, Cephalopods have been termed ‘weeds of the sea’ and many groups have apparently increased over recent decades. Commercially relevant cephalopods such as Loligo forbesii have increased in landings in recent years, but little is known about their vulnerability to over-fishing given their short lifecycles and status as non-quota species. Some trends in landings of this species will be presented, with an analysis of data gaps for its sustainable exploitation. Despite its commercial appeal, basic information including length-maturity data are not routinely captured for L. forbesii; however several discrete EU projects have collected this information in the last three decades. These data have been gathered by the Cephs&Chefs project and will be analysed to provide spatial and temporal trends in length-maturity as well as life-history (sex ratio) and biomass (length-weight) indices. Trends over time in this information will be examined in the context of changing ocean temperatures in the north-east Atlantic

ICES Annual Science Conference, 9-12 September 2019, Gothenburg, Sweden

ICES Annual Science Conference, 9-12 September 2019, Gothenburg, Sweden, Cephalopods are short-lived fast growing species which are highly sensitive to environmental variation, as reflected in wide year-to-year fluctuations in abundance. Understanding the relative importance of environmental variation and fishing mortality in determining stock trajectories is essential to underpin appropriate management measures and support sustainable exploitation of these species. Over three decades ICES WGCEPH has reported on patterns and trends in cephalopod landings in the ICES area but there has been no comprehensive analysis of patterns and trends. We assembled data series on loliginid squid, ommastrephid squid, octopus and cuttlefish from landings (where possible considering landings per unit effort) and survey catches. For most series it is not possible to be sure of the cephalopod species involved so the main analysis is at family level. We used a combination of standard time series analysis, dynamic factor analysis, generalised additive models and generalised additive mixed models to analyse patterns and trends in these datasets and to try to identify the underlying causes of abundance variation and thus provide a basis for deigning management measures. We quantified common trends so as to assess whether cephalopods are generally increasing in abundance. We also separated out the variation related to taxon, country and gear-type, and compared commercial fishery and research survey data. For survey data we examined seasonal and regional variation in abundance. We tested whether observed interannual variation and trends were related to largescale environmental variation (as captured by the NAO and similar indices) and to fishery catches in the previous year

The Workshop on Data Limited Stocks of Short-Lived Species aimed to provide guidelines on the estimation of MSY proxy reference points for category 3–4 short-lived species and to evaluate the management procedures currently in use and their appropriateness for short-lived species by means of Long-Term Management Strategy Evaluations (LT-MSE).In relation to assessment methods for short-lived data-limited stocks and estimation of biological and MSY proxy reference points, the WK focused on the application of SPICT (Pedersen and Berg, 2017). The WK was updated on recent improvements of SPiCT and the harvest control rules (HCRs) used to manage stocks after WKLIFE VII and VIII by including either the MSYfractile or MSY-PA rules. For the optimal SPiCT advice rule, users should refer to the update ICES guidelines. Work on fitting SPICT to case studies was made before and during the workshop: Assessments to Anchovy in 9.a South resulted in a satisfactory fitting of SPICT, whilst fitsto Anchovy in 9.a West and to Sprat 7.de were still unsatisfactory. In addition, there were some presentations on applications of SPiCT to several Cephalopod populations. Length-based indicators of stock status were discarded as generally they are not suitable for short-lived species where recruitment induces major interannual changes in the length distribution of catches. Aprovisional application of a two-stage assessment was presented for Sprat in 7de, but results were still provisional.In relation to the evaluation of management procedures for these stocks, MSE testing of harvest control rules based on trends of biomass indices were analysed for anchovy-, sprat-, and sardinelike stocks including several operating models. All simulations showed that the shorter the lag between observations, advice and management, the bigger the catches and the smaller the risk.This implies that In-year advice should always be preferred over the normal calendar (with an interim) year advice for these stocks. Major drivers of risks are by order of relevance: historical exploitation level (and trajectory), and the harvest control rule (HCR) with its selected Uncertainty Cap (UCap). This emphasizes the relevance of trying an initial assessment of the relative status of the stock regarding optimal exploitation to judge if a precautionary buffer is required to start management. Further work on the assessment of past exploitation level is required.Regarding the trend-based harvest control rules (HCRs): In general, 1-over-2 outperforms 2- over-3 rule (ICES default rule) because for quite similar catches the former implies lower risks. For symmetrical application of the interannual uncertainty cap, best performance (least risks for minimum reduction of catches) occurs using the 1-over-2 rule with a symmetrical 80% uncertaintycap. The riskiest performance results were from applying a 20% uncertainty cap, both for 1-over-2 and 2-over-3, and the performance worsens with time. For asymmetrical Uncertainty Caps, tested for rules with a maximum interannual upward revision of 20%, results showed optimal performance when allowing reductions of 60% or greater percentages from the previousadvices for in-year advice, and of 70% or greater for normal (calendar) advice. While the 1-over-2 rule with asymmetric uncertainty cap is the most precautionary, it implies a continued large reduction of catches. The 1-over-2 rule with no uncertainty cap gives the highest catches at all times. Intermediate rules in terms of balance between catches and risks are: 1-over-2 (with symmetrical80%Ucap) and 1-over-2 with biomass safeguard (using either Imin, the minimum past observed abundance index, or Itrigger, 1.4*Imin). Rule 1-over-2 with symmetrical 80% Uncertainty cap might be preferred as a good compromise between moderate risks and catches though it can lead to major reduction of catches in the long term.Given the trade-off between competing rules, it seems that selection of a rule should better be made in consultancy with managers and stake holders according to their objectives for each fishery.Further research will be needed on the definition of proxies for BRPs and of the optimal harvest control rules (including the SPiCT advice rules) for the management of these SLDLS, covering further testing of biomass safeguards and of asymmetric uncertainty caps or the use of constant or variant harvest rate strategies instead of the trend-based rules.

Poster.-- ICES Annual Science Conference, 9-12 September 2019, Gothenburg, Sweden