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The ICES Working Group on Southern horse mackerel, anchovy and sardine (WGHANSA) assessed the status of anchovy in Atlantic Iberian waters (ane.27.9a; western and southern components) and horse mackerel in Atlantic Iberian waters (hom.27.9a) in the May meeting. The status of anchovy in Bay of Biscay (ane.27.8), sardine in southern Celtic Seas and the English Channel (pil.27.7), sardine in Bay of Biscay (pil.27.8abd) and sardine in Cantabrian Sea and Atlantic Iberian waters (pil.27.8c9a) will be assessed in the November meeting. The status of jack mackerel in Subdivision 10.a.2 (Azores grounds) (jaa.10.a2) won’t be assessed this year, since the advice is provided biannually. The stock of anchovy in Bay of Biscay (ane.27.8) has been above Blim since the reopening of the fishery in 2010. SSB in 2023 has been estimated as the second highest of the historical series. Recruitment (age 1 biomass at the beginning of the year) in 2024 is estimated above the average of the time-series. Harvest rates (catch/SSB) have been stable in the last years. The stock of anchovy in Atlantic Iberian waters (ane.27.9a) is composed by the western component (distributed in areas 9.a North, Central–North, and Central–South) and the southern component (distributed in area 9.a South). The advice is provided for the two components separately for the management calendar from July to June next year. Based on the MSE work developed for each component, the advice is based for the first time on constant harvest rate rules. For the western component, the combined PELACUS and PELAGO acoustic biomass estimate is used as an indicator of stock development and the advice is based on the stock indicator for 2023, multiplied by a constant harvest rate of 0.25, with no biomass safeguard. For the southern component, the relative SSB from an analytical assessment conducted with GADGET is used as the index of stock size development and the advice is based on the stock indicator for 2023, multiplied by a constant

Understanding the key factors influencing population dynamics of fish stocks requires knowledge of their spatial distribution and seasonal habitat selection, but these spatio-temporal dynamics are often not explicitly included in ecological studies and stock assessment models. This study standardized the data of sardine fishery-dependent catch-per- unit- effort (CPUE) from the west coast of Portugal using Bayesian hierarchical spatio-temporal models (BHSTM) with the integrated nested Laplace approximation (INLA). Sardine CPUE was best explained by length of the vessel, vessel ID, month, year, and location (latitude, longitude). In terms of spatio-temporal distribution, sardine biomass prediction maps showed a constant pattern that changed every quarter of the year. In addition, sardine CPUE index showed a cyclical trend along the year with minimum values in July and maximum peak in November. This approach provided insights on variables and corresponding modelling effects that may be relevant in spatio-temporal fishery-dependent data standardization, and that could be applied to other fish species and areas.

The aim of this WD was to explore surplus production models to assess the western component of the anchovy 27.9a stock. Models were fitted to catch per quarter or semester (1991 – 2021) and to one biomass index, the spring acoustic survey (1999 – 2021), or two biomass indices, the acoustic survey and the autumn groundfish survey (1991 – 2018) using SPiCT. Various assumptions regarding the shape of the production curve, the initial biomass depletion and the intrinsic growth rate of the population were combined such that models varied from nearly unconstrained (more complex) to increasingly constrained (less complex). Bi-annual catch data and two survey indices lead to a higher number of convergent models. Several models passed all ICES criteria to accept a SPiCT assessment, except for a higher level of uncertainty in F/FMSY than the agreed one for long-lived stocks. A model assuming a Schaefer production curve, a prior on r from a meta-analysis and, an initial depletion rate of 80%, showed better retrospective analysis, survey hindcast cross-validation and convergence performance than other candidate models. The results indicated that F/FMSY was below 1 across most of the period, B/BMSY fluctuated well below 1 until 2010 and above 1 since 2016. The present results may be considered for further work in a benchmark workshop.

The model speci fications presented below correspond to those benchmarked in WKPELA 2018. The main difference is that results are presented now for the end of the second quarter of each year instead of be presented at the end of the fourth quarter. This responds to practical modi cations in the defi nition of the assessment year, now it goes from July 1st to June 30th of the next year. Specifi c model assumptions for this year are presented in section 2.2 and 3, as well as estimated parameters after optimization in Table 2.

The ESA-supported Primary-productivity in Upwelling Systems (PRIMUS) project aims to provide the best possible characterisation of net primary productivity (NPP) and its relationship to upwelling in Atlantic Eastern Boundary Upwelling Systems (EBUS), including the Iberian/Canary and Benguela systems. It will create a 25-year time series of 1-km satellite-derived NPP over the Atlantic, and, experimentally, at higher-resolution (300m) using the unique capabilities of the MERIS and OLCI satellite sensors. PRIMUS will use these data to advance analyses of Atlantic EBUS including temporal and spatial variability in NPP and its statistical relationship to upwelling and climate indices (such as the North Atlantic Oscillation). PRIMUS will also conduct eight further science cases in specific science áreas / regional settings: aquaculture in Galicia; fisheries and eutrophication in the Portuguese upwelling region; potential EBUS impacts on ocean carbón pools; Lagrangian estimates of NPP; and air-sea interaction and acidification impacts. Science cases will make use of EO and in situ data, as well as numerical model outputs (freely available through the EU’s Copernicus and elsewhere) to investigate the 4D character of EBUS, for example linking Lagrangian NPP with sediment traps samples at depth. PRIMUS will also conduct demonstrations that transfer science into solutions for society, working together with scientific, agency, policy and commercial “early-adopters”, building on three science case studies (EBUS and aquaculture; fisheries; and eutrophication monitoring). Furthermore, evaluating transition of data production to operational initiatives such as Copernicus and GMES and Africa and the potential for data exploitation by the European and international ecosystem modelling community. This communication will present initial results from the 25-year NPP time series and high resolution NPP computations as well as selected science cases

Small pelagic fish (SPF) play extremely important ecological roles in marine ecosystems, form some of the most economically valuable fisheries resources, and play a vital role in global food security. Due to their short generation times and tight coupling to lower trophic levels, populations of SPF display large boom-and-bust dynamics that are closely linked to climate variability. To reveal emerging global research trends on SPF as opposed to more recently published, ecosystem-specific reviews of SPF, we reviewed the literature published in two, 6-year periods in the new millennium (2001–2006, and 2011–2016) straddling the publication of a large, global review of the dynamics of SPF in 2009. We explored intrinsic and extrinsic (bottom-up) factors influencing the dynamics of SPF such as anchovies, sardines, herrings and sprats within the sub-order Clupeidae. Published research efforts within 16 different biogeographic ocean regions were compiled (more than 900 studies) and compared to identify i) new milestones and advances in our understanding, ii) emerging research trends and iii) remaining gaps in knowledge. Studies were separated into 5 categories (field, laboratory, mesocosms, long-term statistical analyses and spatially-explicit modelling) and discussed in relation to 10 bottom-up categories including 5 abiotic factors (temperature, salinity, pH, dissolved oxygen, density), 3 physical processes (advection, turbulence, turbidity) and 2 biotic factors (prey quantity and quality). The peer-reviewed literature reflects changes in the number of studies between the two time periods including increases (Mediterranean Sea, Humboldt Current) and decreases (Australia, Benguela Current). Our review highlights i) gaps in ecological knowledge on young juveniles and, in general, on the impacts of hypoxia and heatwaves on SPF, ii) the utility of paleo studies in exploring population drivers, iii) the continued need to develop spatially-explicit, full life-cycle models, iv) t

Climate change often leads to shifts in the distribution of small pelagic fish, likely by changing the match-mismatch dynamics between these sensitive species within their environmental optima. Using present-day habitat suitability, we projected how different scenarios of climate change (IPCC Representative Concentration Pathways 2.6, 4.5 and 8.5) may alter the large scale distribution of European sardine Sardina pilchardus (a model species) by 2050 and 2100. We evaluated the variability of species-specific environmental optima allowing a comparison between present-day and future scenarios. Regardless of the scenario, sea surface temperature and salinity and the interaction between current velocity and distance to the nearest coast were the main descriptors responsible for the main effects on sardine's distribution. Present-day and future potential “hotspots” for sardine were neritic zones (<250 km) with water currents <0.4 m s−1, where SST was between 10 and 22 °C and SSS > 20 (PSU), on average. Most variability in projected shifts among climatic scenarios was in habitats with moderate to low suitability. By the end of this century, habitat suitability was projected to increase in the Canary Islands, Iberian Peninsula, central North Sea, northern Mediterranean, and eastern Black Sea and to decrease in the Atlantic African coast, southwest Mediterranean, English Channel, northern North Sea and Western U.K. A gradual poleward-eastward shift in sardine distribution was also projected among scenarios. This shift was most pronounced in 2100 under RCP 8.5. In that scenario, sardines had a 9.6% range expansion which included waters along the entire coast of Norway up and into the White Sea. As habitat suitability is mediated by the synergic effects of climate variability and change on species fitness, it is critical to apply models with robust underlying species-habitat data that integrate knowledge on the full range of processes shaping species productivity and distribut

Fishery data is one of the most accessible sources of information currently used for ecological studies and stock assessments. Unlike scientific surveys that are usually restricted to a given time of the year, fisheries dependent data is almost continuously available in time. Moreover, the information collected from the fisheries is less expensive and time consuming. However, for use as a relative abundance index, fishery-dependent data requires standardization as catch-per-unit-effort (CPUE) in order to remove the impact of vessel-specific differences and fishing behavior. Understanding the key factors that influence the population dynamics of fish species implies assessment of their spatial distribution and seasonal habitat selection but, spatio-temporal dependence issues are often not explicitly included in the modeling process. This study standardizes sardine fishery-dependent data obtained from the west coast of Portugal as CPUE by means of a Bayesian hierarchical spatio-temporal model using integrated nested Laplace approximation (INLA). This is one of the first studies of the region to provide maps of the relative abundance of this species for all months of the year. The best model included length of the vessel, vessel ID, month, year and location (latitude, longitude), while none of the five environmental covariates (Chl-a, SST, bathymetry, current velocity and direction) were relevant. In terms of spatial distribution, sardines were more abundant in the northern area, especially during the last quarter of the year. The applied methodology has contributed to improve our knowledge of European sardine distribution throughout the year, providing accurate predictive maps and insights into the standardization process of fishery-dependent data that could also be applied to other fish species and areas.

The Atlantic chub mackerel Scomber colias has become an increasingly important commercial species in the European Atlantic waters in the last 10–15 years, probably through an expansion process from NW African waters and due to market needs. However, at present there are no assessment or advice requirements. In the WK framework, available information of the species in the West Atlantic waters has been compiled in order to evaluate possible geographical differences and trends, and the feasibility to describe its population structure. Though the Atlantic chub mackerel is not routinely included among the target species in the acoustic surveys performed in the Atlantic Iberian waters and the Mediterranean Sea, a synoptic overview of the species is possible over all its West Atlantic distribution. Moreover, the data available have indicated latitudinal trends, mainly in the landings’ length composition, L50 and the spawning periods. Nevertheless, even if some degree of connectivity likely exists and migrations are occurring between adjacent areas, some subunits could be considered for management purposes. From the assessment models’ trials carried out, the results or reference points obtained for the European fisheries cannot be retained at present. Therefore, continuing collating information from fisheries and biological sampling of the species, obtaining reliable biomass estimations from scientific surveys and identifying management units seem the main priorities to address in future research work and in case of assessment requirements.

Small pelagic fish (SPF) play extremely important ecological roles in marine ecosystems, form some of the most economically valuable fisheries resources, and play a vital role in global food security. Due to their short generation times and tight coupling to lower trophic levels, populations of SPF display large boom-and-bust dynamics that are closely linked to climate variability. To reveal emerging global research trends on SPF as opposed to more recently published, ecosystem-specific reviews of SPF, we reviewed the literature published in two, 6-year periods in the new millennium (2001–2006, and 2011–2016) straddling the publication of a large, global review of the dynamics of SPF in 2009. We explored intrinsic and extrinsic (bottom-up) factors influencing the dynamics of SPF such as anchovies, sardines, herrings and sprats within the sub-order Clupeidae. Published research efforts within 16 different biogeographic ocean regions were compiled (more than 900 studies) and compared to identify i) new milestones and advances in our understanding, ii) emerging research trends and iii) remaining gaps in knowledge. Studies were separated into 5 categories (field, laboratory, mesocosms, long-term statistical analyses and spatially-explicit modelling) and discussed in relation to 10 bottom-up categories including 5 abiotic factors (temperature, salinity, pH, dissolved oxygen, density), 3 physical processes (advection, turbulence, turbidity) and 2 biotic factors (prey quantity and quality). The peer-reviewed literature reflects changes in the number of studies between the two time periods including increases (Mediterranean Sea, Humboldt Current) and decreases (Australia, Benguela Current). Our review highlights i) gaps in ecological knowledge on young juveniles and, in general, on the impacts of hypoxia and heatwaves on SPF, ii) the utility of paleo studies in exploring population drivers, iii) the continued need to develop spatially-explicit, full life-cycle models, iv) t

The main task of WGHANSA was to assess the status of the stocks of sardine in the Celtic Seas and English Channel (pil.27.7), sardine in the Bay of Biscay (pil.27.8abd), sardine in the Cantabrian Sea and Atlantic Iberian waters (pil.27.8c9a), anchovy in the Bay of Biscay (ane.27.8), anchovy in Atlantic Iberian waters (ane.27.9a; components west and south), horse mackerel in Atlantic Iberian waters (hom.27.9a) and jack mackerel in the Azores (jaa.27.10). Assessments and short-term forecasts were updated with modifications to mitigate the impact of missing surveys in 2020 due to the COVID19 disruption. For sardine in 8c9a, the PELAGO index was raised by a linear regression model to accommodate the lack of the PELACUS estimation; the age composition of PELAGO was assumed to represent the whole stock. The biomass of sardine (age 1+) is above MSY Btrigger for the first time since 2009. Fishing mortality is the lowest in the time-series but still above FMSY. To answer a special request from Portugal and Spain catch scenarios for 2020 were revised. For anchovy 9a.west, the PELAGO index was raised by a linear regression to accommodate the lack of the PELACUS2020 estimate. The stock size indicator increased from 4129 tonnes in 2019 to 56 526 tonnes in 2020. The harvest rate increased from 0.155 in management year 2018 to 0.63 in management year 2019. The relative SSB of anchovy 9.a.south increased 26% from 2019 to 2020 being well above Bpa. Relative Fishing mortality (F) has fluctuated with no clear trend. From management year 2018 to 2019, relative F decreased 22%. The index ratio (1over2 rule) showed a 98% increase of the stock size indicator in 2020. The assessment of horse mackerel in Division 9.a was modified due to the lack of the Portuguese demersal survey in autumn 2019. The SSB reached a historical maximum in 2020 of 1 102 627 tonnes. High recruitment since 2011 has contributed to the SSB increase. Fishing mortality, estimated to be 0.028 year -1 in 2019 has been be