Defining métier for the Celtic Sea mixed fisheries: A multiannual international study of typology

There is growing international focus on ecosystem based fisheries management. Within the EU this has manifested in the provision of mixed fisheries advice, using the FCube model. The operational implementation and accuracy of this model relies on accurate identification of the technical interactions between fleets, gears and the resulting composition of species in the retained catch. These interactions are defined using units of fishing activity based on gear type and target species assemblage, but with no consideration for spatiotemporal heterogeneity. We assess the relevance of the fishing units used in relation to the spatial and temporal trends in retained catch within the Celtic Sea. To achieve this multivariate analysis (principal component and hierarchical clustering) were conducted to identify homogenous groupings of fishing activity using 5 years of international Celtic Sea retained catch data. The groupings identified demonstrate that a fairly simplistic structure of fishing activity units (country of provenance, fishing location, gear and target species) can effectively describe the complex mixed fisheries scenarios being executed within the Celtic Sea consistently across multiple years. This international and multiannual analysis improves our understanding of the mixed fisheries scenarios within the Celtic Sea and reveals a multifaceted spatial structure in the species assemblages landed, indicating the presence of several distinct mixed fisheries within the region appropriate for mixed fisheries analyses

Benchmark Workshop on selected stocks in the Western Waters in 2021 (WKWEST).

The goal of a benchmark is consensus agreement on an assessment methodology that is to be used in future update assessments. This assessment methodology can be an analytical assessment, but can also be non-analytical, for instance based on trends in an assessment or in a selected set of (survey) indicators, with or without forecasts. The result will be the 'best available' method that ICES advice will be based on. WKWEST 2021 dealt with the following stocks: Sardine (Sardina pilchardus) in Subarea 7 (southern Celtic Seas, and the English Channel); Pollack (Pollachius pollachius) in subareas 6-7 (Celtic Seas and the English Channel); Red gurnard (Chelidonichthys cuculus) in subareas 3–8 (Northeast Atlantic); Plaice (Pleuronectes platessa) in divisions 7.h–k (Celtic Sea South, southwest of Ireland); Sole (Solea solea) in divisions 8.c and 9.a (Cantabrian Sea and Atlantic Iberian waters)

ICES. 2023. Working Group on Southern Horse Mackerel, Anchovy and Sardine (WGHANSA).

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 harvest rate of 0.5 with a biomass safeguard. In the last years sardine in the Bay of Biscay (pil.27.8abd) shows a decreasing trend in SSB. In 2023 spawning-stock biomass is estimated below MSY Btrigger, Bpa and above Blim. Since 2013 the fishing mortality has been oscillating above FMSY and Fpa, and below Flim. The advice for sardine in southern Celtic Seas and the English Channel (pil.27.7) is based on the PELTIC survey biomass index in the total area. The index ratio indicates an increase of 62% in 2023 compared with the two previous years. The biomass (age 1+) of sardine in Atlantic Iberian waters (pil.27.8c9a) in 2023 is estimated to be above MSY Btrigger, Bpa and Blim for the fourth consecutive year. Fishing mortality in 2022 is below FMSY. ICES advice is based on the ICES MSY advice rule. However, the catch options explored for 2024 include several harvest control rules that were assessed by ICES as precautionary. The SSB of horse mackerel in Atlantic Iberian waters (hom.27.9a) fluctuated from 1992 (the beginning of the assessment) to 2013 and afterwards has increased continuously to historical maximum values in 2023. In 2023 SSB is estimated at 1 214 200 tonnes, well above MSY Btrigger, Bpa, and Blim. Fishing mortality has been below FMSY over the whole time-series, with a decreasing trend in the last years. Recruitment shows a decreasing trend from 2017 to 2021 but is still above the average of the time series. The lack of the survey index in 2019 and 2020 is reflected in larger confidence intervals for SSB and recruitment in the last years. The jack mackerel in Subdivision 10.a.2 (Azores grounds) (jaa.10.a2) is classified in category 5 and advice is provided biannually. The latest advice for this stock was provided last year.This work was mainly funded by a European Union-Next Generation EU project. Agreement of the Ministry of Agriculture, Fishing and Food, as well as the Spanish Research Council (CSIC) through the Spanish Oceanographic Institute (IEO). Project Math4Fish: New tools for mathemat-ical modelling in stock assessment of spanish fisheries

ICES. 2019. Working Group on Southern Horse Mackerel, Anchovy and Sardine (WGHANSA).

The Working Group on Southern Horse Mackerel, Anchovy and Sardine (WGHANSA1) met by correspondence from 3 to 7 June 2019, and in Madrid from the 25 to the 28 of November 2019, and was chaired by Alexandra Silva (Portugal). There were 13 participants from France, Portugal, Spain and UK. The main task of WGHANSA was to assess the status 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 according to the stock annexes. There is no assessment method adopted for pil.27.7 due to the lack of data. The stock of pil.27.8abd was assessed as category 1 for the first time, following an interbenchmark. Recruitment has been above the average, the spawning–stock biomass declined and fishing mortality steeply increased in 2010–2012. SSB is fluctuating above MSY Btrigger and F2018 is above FMSY and below Fpa. This year, the DEPM datapoint for 2017 was included in the pil.27.9a assessment for the first time, following a revision of the survey data. The stock has decreased since 2006 and stabilized to a historical low since 2012. The biomass of age 1 and older fish has been decreasing since 2006 and reached the lowest historical value in 2015. It has since increased slightly but is below Blim since 2011. Recruitment has been below the time-series average since 2005. Recruitment in 2018 was around the geometric mean of the last five years. Fishing mortality has been decreasing from a peak in 2011. In 2018, it was the lowest in the time-series and below Fpa and Flim. The stock size indicator for anchovy in 9a.west decreased 90% from 2018 to 2019 (4129 t), after a period of an increasing trend since 2014. The harvest rate decreased 67% from management year 2017 to 2018 being below the median of the historical time-series.The relative spawning–stock biomass of the south component of the anchovy 9.a stock has fluctuated without a trend over the time-series, with most of the values above Bpa. From 2018 to 2019, the relative SSB decreased 5% but is still well above Bpa. Relative Fishing mortality (F) has fluctuated with no clear trend. From management year 2017 to 2018, relative F decreased 93%. The SSB of horse mackerel in Division 9.a fluctuated from 1992, the beginning of the assessment period, to 2012–2013 and afterwards increased continuously to a historical maximum, in 2018. The consistently high recruitment since 2011 has contributed to the SSB increase. Fishing mortality was 0.029 year -1 in 2018, showing a 29% decrease compared to 2017. Fishing mortality has been below FMSY over the whole time-series. The spawning–stock biomass has been above MSY Btrigger over the whole time-series. The exploration of data on anchovy abundance-at-age from juvenile surveys IBERAS-JUVESAR and ECOCADIZ-RECLUTAS indicated the series are still short to conclude about their future incorporation into the assessments. The analyses of internal consistency of the indices and of their consistency with spring acoustic surveys showed promising results for ECOCADIZ-RECLUTAS and pointed out the need to revisit the results of some of the surveys, particularly the IBERAS_JUVESAR series. For sardine, 0-group abundance from IBERAS-JUVESAR (2013–2019) combined with data from an earlier autumn survey, SAR-PT-AUT (discontinued in 2008) covering the northwestern Iberian waters, showed a significant correlation with the abundance of age 1 individuals in surveys carried out in the following spring

a4a short research project. Spatial effects on the stock dynamics of European Atlantic sardine stocks

Under the scope of the a4a Initiative a workshop dedicated to studying spatial effects on the stock dynamics of European Atlantic sardine took place in Ispra, Italy, the 14th to the 18th of December 2015, with the objectives of (i) explore a4a methods to assess the Southern sardine stock (Atlanto-Iberian stock) and compare the results with the current ICES assessment carried out with SS3; (ii) explore a4a methods to assess the Northern stock of sardine stock; and (iii) apply a4a to assess putative sub-stock units; discuss local depletion and mixing among sub-units of the stock. Sardine is fished mainly by UK, Netherlands France, Spain and Portugal across ICES areas VII, VIII and IXa. In France, Spain and Portugal sardine has significant social and economic importance to the fishing and canning industries. Sardine shows a complex population structure characterized by spatial heterogeneity in phenotypic characters and life-history traits. Evidence of spatial variability in dynamics does not preclude some fish mixing across the whole region, in agreement with both genetic homogeneity and the similarity in otolith element composition in larger fish. Current knowledge on sardine biology and dynamics is consistent with the hypothesis of a meta-population composed of three populations recruiting in the Bay of Biscay, off northern Portugal, and in the Gulf of Cadiz. The workshop looked into three options of spatial structures (i) current stock structure Bay of Biscay stock (BB; VIIIa,b) and Ibero Atlantic stock (IB; IXa and VIIIc); (ii) three separate sub-units Bay of Biscay, Northwest stock (NW; VIIIc, IXa-North to IXa-Central South) and South stock (S; IXa South); and (iii) a single stock. The a4a stock assessment model was used to estimate the dynamics of each sub-units in each option. To carry out the comparison across sub-units the models used were kept as similar as possible, to mitigate the effect that the choice of model can have on the final results. Uncertainty was estimated using MCMC with the ADMB implementation, which, in the most recent version, can be assessed through the FLa4a package. In the case of the overall stock, a sensitivity analysis about survey's data processing options was carried out, to investigate the robustness of the assessment results. For the Bay of Biscay a bayesian approach has also been implemented. In order to compare both methods (a4a and bayesian) a very simple separable model was selected. A visual evaluation of the consistency between the spatial hypothesis was done based on the SSB estimates, showing that both trends are remarkably similar until 2012, when they start to diverge. In 2012 the Iberian stock (sub-units NW and S) was at a very low level and the migration rates between the Iberian and the Bay of Biscay sub-units may have increased. In such case, the stock assessment model assumption of closed population is less likely to be maintained and the two estimates of SSB diverge. One of the advantages of the approach proposed is to make it possible to look into sub-units of the stock with regards to their productivity and exploitation. These results are shown as time series of fishing mortality and recruitment for each sub-unit.JRC.E.6-Demography, Migration and Governanc

ICES. 2020. Working Group on Acoustic and Egg Surveys for Sardine and Anchovy in ICES areas 7, 8 and 9

he Working Group on Acoustic and Egg Surveys (WGACEGG) coordinates pelagic surveys for a number of stocks and provides monitoring for the two major sardine and anchovy stocks in ICES areas 6, 7, 8, and 9. The group evaluated small pelagic fish biomass indices derived from acoustic and Daily Egg Production Method (DEPM) surveys in ICES areas 6, 7, 8 and 9. These indices have been provided to the ICES Working Group on Southern Horse Mackerel, Anchovy and Sardine (WGHANSA), the Working Group on Widely Distributed Stocks (WGWIDE) and the Herring Assessment Working Group for the Area South of 62ºN (HAWG) stock assessment group, to serve as fishery-independent input for analytical assessment purposes. DEPM and acoustic indices were derived based on data collected using independent methods. Acoustic- and DEPM-derived biomass indices from quasi-synoptic surveys conducted in the Bay of Biscay in spring were compared, to assess the presence of potential bias and to improve the precision of fish stock biomass estimates. The DEPM-based anchovy biomass index was 22% higher than the acoustic index in 2019. Unusual concentrations of anchovy in Eastern Cantabrian Sea, an area not covered by the acoustic survey, and the presence near the sea surface of actively spawning individuals possibly under-sampled by acoustics in central Bay of Bay had been postulated as potential causes of this discrepancy. No significant difference was found between sardine biomass indices derived from DEPM and acoustics in 2019. The group has updated its database of standard gridded maps covering the European Atlantic area. This initiative continues to inform on the spatial dynamics of various parameters collected during the surveys coordinated under the auspices of the group (fish acoustic densities, anchovy and sardine egg abundance, surface temperature and salinity). Results of an analysis of the time series of gridded maps (anchovy and sardine acoustic density, surface salinity and temperature) showed quantitative changes in the spatial and temporal distribution of anchovy and sardine over the last 15 years, and further define their habitats in European Atlantic waters in spring. The timing and spatial coverage of DEPM and acoustic surveys that will be conducted by group members in 2020 were planned to optimise the monitoring of anchovy and sardine populations and their pelagic environment in the European Atlantic area. The synoptic nature of the survey components has been assessed for each target species. A manual describing the protocols used during the DEPM surveys coordinated by the WGACEGG group was reviewed, and writing of a manual of WGACEGG acoustic surveys continued. Both manuals will be available in 2020. The final results of the 2017 sardine DEPM assessment were endorsed by the group

Towards transdisciplinary decision-support processes in fisheries: experiences and recommendations from a multidisciplinary collective of researchers

The shifting policy focus towards Ecosystem Based Management in Fisheries (EBFM) requires the integration of knowledge and disciplines and the engagement of stakeholders to support decision-making processes. Scientists contribute to this through (i) participatory research projects, (ii) stakeholder partnerships and (iii) institutional scientific advice processes. Understanding the role of scientists in such processes, the nature of the interactions between scientists, stakeholders and managers in knowledge integration and the link between science and policy is an emerging field of research addressing transdisciplinary challenges. In 2018, Ifremer-UMR AMURE organized the workshop ‘Science, Partnership and Decision-support in Fisheries’ bringing together international scientists from natural and social sciences to conduct a review based on twenty concrete case studies. Findings indicate that science-stakeholder-manager partnerships for decision-support in fisheries can play an essential role in the transition to EBFM. To foster this transition, eight recommendations are presented that cover the roles of the different participants, the expectations of partnerships, capacity building, the integration of the social sciences, and funding structures. Further, it is recommended that future research and innovation framework programmes into sustainable fisheries and other ocean uses should explicitly include mechanisms to foster transdisciplinary approaches and the development of best practices. Building-up networks and developing reflexive approaches to review experiences and practices for transdisciplinary approaches in EFBM decision-support will contribute to design the next generation transdisciplinary platforms and generating actionable knowledge towards EBFM

ICES. 2020. Working Group on Acoustic and Egg Surveys for Sardine and Anchovy in ICES areas 7, 8 and 9

he Working Group on Acoustic and Egg Surveys (WGACEGG) coordinates pelagic surveys for a number of stocks and provides monitoring for the two major sardine and anchovy stocks in ICES areas 6, 7, 8, and 9. The group evaluated small pelagic fish biomass indices derived from acoustic and Daily Egg Production Method (DEPM) surveys in ICES areas 6, 7, 8 and 9. These indices have been provided to the ICES Working Group on Southern Horse Mackerel, Anchovy and Sardine (WGHANSA), the Working Group on Widely Distributed Stocks (WGWIDE) and the Herring Assessment Working Group for the Area South of 62ºN (HAWG) stock assessment group, to serve as fishery-independent input for analytical assessment purposes. DEPM and acoustic indices were derived based on data collected using independent methods. Acoustic- and DEPM-derived biomass indices from quasi-synoptic surveys conducted in the Bay of Biscay in spring were compared, to assess the presence of potential bias and to improve the precision of fish stock biomass estimates. The DEPM-based anchovy biomass index was 22% higher than the acoustic index in 2019. Unusual concentrations of anchovy in Eastern Cantabrian Sea, an area not covered by the acoustic survey, and the presence near the sea surface of actively spawning individuals possibly under-sampled by acoustics in central Bay of Bay had been postulated as potential causes of this discrepancy. No significant difference was found between sardine biomass indices derived from DEPM and acoustics in 2019. The group has updated its database of standard gridded maps covering the European Atlantic area. This initiative continues to inform on the spatial dynamics of various parameters collected during the surveys coordinated under the auspices of the group (fish acoustic densities, anchovy and sardine egg abundance, surface temperature and salinity). Results of an analysis of the time series of gridded maps (anchovy and sardine acoustic density, surface salinity and temperature) showed quantitative changes in the spatial and temporal distribution of anchovy and sardine over the last 15 years, and further define their habitats in European Atlantic waters in spring. The timing and spatial coverage of DEPM and acoustic surveys that will be conducted by group members in 2020 were planned to optimise the monitoring of anchovy and sardine populations and their pelagic environment in the European Atlantic area. The synoptic nature of the survey components has been assessed for each target species. A manual describing the protocols used during the DEPM surveys coordinated by the WGACEGG group was reviewed, and writing of a manual of WGACEGG acoustic surveys continued. Both manuals will be available in 2020. The final results of the 2017 sardine DEPM assessment were endorsed by the group

Modélisation de l'incorporation du carbone photosynthétique en environnement marin piloté par ordinateur

PARIS-BIUSJ-Thèses (751052125) / SudocPARIS-BIUSJ-Physique recherche (751052113) / SudocSudocFranceF