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WGIPS met in January 2023 to combine and review the results of the annual pelagic ecosystem surveys and provide indices for the stocks of herring, sprat, mackerel, boarfish, and blue whiting in the Northeast Atlantic, Norwegian Sea, North Sea, and Western Baltic. Timing, coverage and methodologies were assessed and coordinated for the upcoming 2023 surveys. Progression on the update of the WGIPS survey manual (SISP 9) in the TIMES format continued, with an expected first draft to be submitted in spring 2023 and the completion planned within the present WGIPS reporting cycle. The group discussed the future and development of databases used by the group (the ICES DB and the PGNAPES database). The use of StoX and progress on TAF were reviewed during a joint session with the ICES Data Centre and the StoX development team. The biological sampling strategies in WGIPS surveys continue to be discussed and progress is being made on documenting the sampling strategies used in all WGIPS surveys in the new format of the sampling manual. The planned workshop on sampling strategies in the HERAS survey has been postponed until further progress is made on data availability for analysis. WGIPS reviewed progress in using genetic stock separation methods for splitting survey results to component herring stocks and assessed ways forward for the development of these methods whilst maintaining the integrity of the survey indices. The group encourages continued close collaboration of the ICES survey and assessment groups and institutes carrying out the genetic analysis work. WGIPS continues to follow progress on mesopelagic fish sampling in the International Blue Whiting Spawning Survey (IBWSS) through updates from the Ecologically and Economically Sustainable Mesopelagic Fisheries EU project (MEESO) and other developments within this area of relevance to the WGIPS surveys.

The core objectives of the Working Group on International Pelagic Surveys (WGIPS) are to combine and review the results of annual pelagic ecosystem surveys to provide indices for the stocks of herring, sprat, mackerel, boarfish, and blue whiting in the Northeast Atlantic, Norwegian Sea, North Sea, and Western Baltic; and to coordinate timing, coverage and methodologies for the upcoming 2022 surveys. To support this work, the group is drafting an update to the Series of ICES Survey Protocols 9 - Manual for International Pelagic Surveys (SISP9-IPS). This past year, WGIPS held a number of focal sessions including: (1) a session for presenting auxiliary monitoring of ecosystem components beyond the standard fishery survey results for the target species. This session has been held annually since 2019, with presentations this year on tests with an in-trawl stereo camera system during part of the 2021 International Ecosystem Summer Survey in the Nordic Seas (IESSNS), (2) a session on the future and development of databases used to store data from surveys in WGIPS (ICES Acoustic Database and the “PGNAPES” database), developments and use of the acoustic survey analysis software “StoX” and progress on adopting the ICES Transparent Assessment Framework (TAF) for archiving and documenting acoustic index calculations, and (3) a session on biological sampling strategies in WGIPS surveys. The group is documenting the sampling strategies used in all WGIPS surveys (on request from ICES Working group on Acoustic Trawl Data Portal Governance (WGAcousticGov) and is planning a workshop on sampling strategies in the ICES Coordinated Acoustic Survey in the Skagerrak and Kattegat, the North Sea, West of Scotland and the Malin Shelf area (HERAS). The group also reviewed progress on mesopelagic sampling with an update from the European Union Horizon 2020-programme on Ecologically and Economically Sustainable Mesopelagic Fisheries (MEESO), presentations on new net developmen

Seamounts have long been recognised as hotspots for pelagic productivity and diversity in the world’s open ocean habitats. Recent studies have suggested that productivity may vary greatly between different seamounts, depending on complex interactions between the bathymetric features and local oceanography. These processes may enhance local primary production which support elevated biomass at higher trophic levels. In addition to enhancing local biomass, seamounts may also act as aggregative features, attracting pelagic species from the surrounding waters. Such characteristics make seamounts attractive targets for fisheries. However, as these unique habitats are localised and relatively small, they are vulnerable to overexploitation, which may have detrimental impact on the wider region. Mapping and quantitative assessments of the fish biomass at different seamounts are crucial prerequisites to identifying vulnerable seamounts and will aid toward understanding the dynamics of these important ecosystems and their vulnerability to fishing pressures. We used fisheries acoustics during two expeditions in 2018 and 2019, to investigate the distribution and abundance of fish and micronekton on and around five little studied seamounts of Tristan da Cunha, a remote archipelago in the South Atlantic Ocean. The results confirmed increased productivity at the seamounts, compared to the surrounding open ocean with higher acoustic backscatter values, a proxy for biomass, particularly at the shallower (~200 m depth) seamounts. Fish largely dominated the backscatter on most of the seamounts especially over the plateau areas where large densities of prey fish, primarily the mesopelagic Maurolicus inventionis, were detected. Very large aggregations, thought to consist of bentho-pelagic fish, were also observed over the slope of McNish Seamount that resulted in very high biomass estimates. Aggregations of this size and magnitude, have, to our knowledge, never been mapped or quantified

This year the group changed its name to Working Group on Acoustic and Egg Surveys for small pelagic fish in NE Atlantic (WGACEGG). WGACEGG coordinates, assesses and quality controls acoustic and daily egg production (DEPM) surveys of several pelagic stocks in ICES areas 6-9. During three 2020 WGACEGG meetings, results of three DEPM surveys, three spring/summer acoustic surveys and all six autumn surveys were presented. Implications of the cancellation of three surveys (SAREVA and PELACUS (Spain)) and PELGAS (France) were also discussed, as were possible mitigations to minimize the effects on the relevant stock assessments. No concerns were raised about the surveys that took place. The results from the DEPM survey for sardine in 9a could not be provided until December, as COVID-19 had restricted laboratory access. WGACEGG also met with members of the Working Group on Southern Horse Mackerel, Anchovy, and Sardine (WGHANSA) to present the results from the 2020 Portuguese (PELAGO) acoustic survey in advance of the June assessment meeting. The working groups discussed the implications of PELAGO using a different vessel and of the earlier timing (compared to the timeseries) on the sardine and anchovy indices. The joint meeting also identified which surveys were at risk of being cancelled because of COVID-19 and discussed possible mitigations. Biomass estimates for both sardine and anchovy in division 9a were higher than observed in recent years as confirmed by both acoustic and DEPM surveys; DEPM derived Bay of Biscay anchovy spawning stock biomass was the highest on record although the number of recruits in the Bay of Biscay observed later in autumn did not reflect this increase. However, this was at least partly due to a northwards expansion into the English Channel where Bay of Biscay juveniles were found for the first time; sardine biomass in the Bay of Biscay from all available surveys suggested slightly lower values than the long-term average; in the English Channel

The core objectives of The Working Group of International Pelagic Surveys (WGIPS) are to combine and review results of annual pelagic ecosystem surveys to provide indices for the stocks of herring, sprat, mackerel, boarfish, and blue whiting in the Northeast Atlantic, Norwegian Sea, North Sea, and Western Baltic; and to coordinate timing, coverage and methodologies for upcoming surveys. Results from all WGIPS surveys as well as coordination plans for multinational pelagic acoustic surveys and individual surveys were the primary focus at meetings over the past 3 years (2019-2021). WGIPS discussed developments and experiences with the ICES database and the survey analysis software StoX. WGIPS recommends that all surveys use StoX as the primary method for biomass and abundance estimation, and this has been a welcome improvement in the overall working of the group for the surveys that use StoX. Harmonising procedures across surveys increases transparency and promotes understanding and sharing of survey methods within the group. In 2021, a session was held to begin the process of moving surveys onto the Transparent Assessment Framework (TAF). Some surveys had started the TAF process before the meeting and their pro- gress was presented to the group. WGIPS will work with the ICES Data Centre to produce aworkflow and/or documentation to assist with the transition to TAF. Harmonising surveying techniques that measure other aspects of the marine ecosystem has been flagged as requiring attention. As such, the group annually assessed auxiliary pelagic ecosystem surveying techniques currently used on surveys coordinated by WGIPS. The discussions highlighted the range of additional work being undertaken across the group. WGIPS has continued to respond to requests from other ICES expert groups and contribute to workshops. In 2021, WGIPS held a subgroup made up of IBWSS participants (NO, FO, NL, IE, ES) to discuss the formulation of scrutiny procedures t

Identification of the potential habitat of European anchovy (Engraulis encrasicolus) at different life stages in relation to environmental conditions is an interesting subject from both ecological and management points of view. For this purpose, acoustic data from different seasons and different parts of the Mediterranean Sea along with satellite environmental and bathymetry data were modelled using generalized additive models. Similarly, egg distribution data from summer ichthyoplankton surveys were used to model potential spawning habitat. Selected models were used to produce maps presenting the probability of anchovy presence (adults, juveniles and eggs) in the entire Mediterranean basin, as a measure of habitat adequacy. Bottom depth and sea surface chlorophyll concentration were the variables found important in all models. Potential anchovy habitats were located over the continental shelf for all life stages examined. An expansion of the potential habitat from the peak spawning (early summer) to the late spawning season (early autumn) was observed. However, the most suitable areas for the presence of anchovy spawners seem to maintain the same size between seasons. Potential juvenile habitats were associated with highly productive inshore waters, being less extended and closer to coast during winter than late autumn. Potential spawning habitat in June and July based on ichthyoplankton surveys overlapped but were wider in extent compared with adult potential habitat from acoustics in the same season. Similarities and dissimilarities between the anchovy habitats as well as comparisons with sardine habitats in the oligotrophic Mediterranean Sea and other ecosystems with higher productivity are discussed

Identification of potential juvenile grounds of short-lived species such as European sardine (Sardina pilchardus) in relation to the environment is a crucial issue for effective management. In the current work, habitat suitability modelling was applied to acoustic data derived from both the western and eastern part of the Mediterranean Sea. Early summer acoustic data of sardine juveniles were modelled using generalized additive models along with satellite environmental and bathymetry data. Selected models were used to construct maps that exhibit the probability of presence in the study areas, as well as throughout the entire Mediterranean basin, as a measure of habitat adequacy. Areas with high probability of supporting sardine juvenile presence persistently within the study period were identified throughout the Mediterranean Sea. Furthermore, within the study period, a positive relationship was found between suitable habitat extent and the changes in abundance of sardine juveniles in each study area.