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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

This report contains an outline of a working plan for the monitoring of small pelagic fish on the Dutch Continental Shelf. Pelagic fish include species that are not connected to the bottom and live large parts of their life in schools in midwater. Stakeholders within the North Sea Counsel (Noordzeeoverleg) discussed what kind of research is required in the context of sustainable economic use of the North Sea. This resulted in the North Sea Agreement (Noordzeeakkoord - NZA). Part of the North Sea Agreement is the Monitoring-Research- Nature Restoration-Species Protection (Monitoring-Onderzoek-Natuurherstel-Soortbescherming - MONS). A commission has defined the research questions that are at stake and the sort of research that is required to answer these questions from 2022 onwards. Part of this research has received priority - labelled “No regret studies” - of which the monitoring of small pelagic fish is one. The MONS commission has asked Wageningen Marine Research (WMR) to make a proposal for the monitoring of small pelagic fish in the next five years. The first year is a pilot year meant for testing (parts) of proposed methods. The key questions of the client are “What is the distribution of small pelagic fish species in Dutch waters, by season and from year to year?” and “How can these geographical and temporal distributions be explained by the known natural history of the species involved, in terms of known behaviour and habitat requirements?”. This information is required to describe the starting situation for future impact assessments of windfarms construction and other offshore infrastructural building. In addition, the client asks that the plan consists of the following components: (1) A year-round beach sampling of the shallow surf zone and (2) A year-round and annual sampling of small pelagic fish. A summary is given of existing and innovative survey methods. Followed by an overview of historic research on small pelagic fish and of coordinated internationa

In de Eems komt relatief veel jonge haring voor. Dat is bekend door monitoring met de ankerkuil die sinds 2006 in het kader van de Kaderrichtlijn Water tweemaal per jaar wordt uitgevoerd door Bioconsult in opdracht van Nederland en Duitsland. Omdat er weinig gegevens bekend zijn over pelagische vis in de Waddenzee is het niet duidelijk of de situatie in de Eems-Dollard wezenlijk anders is of dat er op andere plekken in de Waddenzee ook veel haring voorkomt. In deze studie richten we ons op het voedsel als sturende factor. Op verzoek van ED2050 hebben we in najaar 2021 een eerste onderzoek uitgevoerd waarbij het dieet van haring, gevangen op twee plekken in de Eems (Spijk en Oterdum), is geanalyseerd met behulp van DNA metabarcoding om de soortensamenstelling van de maaginhoud te bepalen. Behalve het dieet hebben we ook de maagvulling, de staat van vertering en de conditie van de jonge haring geanalyseerd.Op beide locaties is gedurende twee dagen zowel bij eb als bij vloed bemonsterd, waardoor ook een beeld is verkregen van het effect van het getij op het foerageergedrag en dieet. Het is namelijk voorstelbaar dat haring vooral op een bepaald moment in het getij foerageert.De vragen die we met de studie wilden beantwoorden waren:1. Waaruit bestaat het voedsel van de jonge haring in de Eems? 2. Zijn er verschillen in dieet of andere voedselgerelateerde factoren (maagvulling, mate van vertering of conditie) tussen de twee plekken in het gebied en tussen getijfasen? 3. Geeft de soortsamenstelling in de magen een indicatie of de haring ter plekke heeft gefoerageerd?Uit de DNA metabarcoding analyse bleek dat het voedsel van de jonge haring vooral bestond uit Mysidae (aasgarnalen), waarbij Neomysis americana en Neomysis integer veel voorkomende soorten waren. Ook Acartidae (roeipootkreeften) zijn veel gevonden. In het dieet kwam ook relatief vaak haring voor. Dat wordt waarschijnlijk veroorzaakt door materiaal van de maagwand van de haringen zelf, maar consumptie van haring

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

Bycatch is considered one of the most significant threats affecting cetaceans worldwide. In the North Sea, bottom-set gillnets are a specific risk for harbor porpoises (Phocoena phocoena). Methods to estimate bycatch rates include on-board observers, remote electronic monitoring, and fishermen voluntarily reporting; none of these are systematically conducted. Additionally, necropsies of stranded animals can provide insights into bycatch occurrence and health status of individuals. There are, however, uncertainties when it comes to the assessment of bycatch in stranded animals, mainly due to the lack of diagnostic tools specific for underwater entrapment. We conducted a literature review to establish criteria that aid in the assessment of bycatch in small cetaceans, and we tested which of these criteria applied to harbor porpoises retrieved from gillnets in the Netherlands (n = 12). Twenty-five criteria were gathered from literature. Of these, “superficial incisions,” “encircling imprints,” and “recent ingestion of prey” were observed in the vast majority of our confirmed bycatch cases. Criteria like “pulmonary edema,” “pulmonary emphysema,” and “organ congestion” were also frequently observed, although considered unspecific as an indicator of bycatch. Notably, previously mentioned criteria as “favorable health status,” “absence of disease,” or “good nutritional condition” did not apply to the majority of our bycaught porpoises. This may reflect an overall reduced fitness of harbor porpoises inhabiting the southern North Sea or a higher chance of a debilitated porpoise being bycaught, and could result in an underestimation of bycatch rates when assessing stranded animals.

In het kader van het Mosselconvenant zijn afspraken gemaakt over de optimalisatie van de kweekpercelen in de westelijke Waddenzee. Dit houdt in dat er nieuwe kweekpercelen voor mosselen uitgegeven worden op locaties waarvan men verwacht dat goede rendementen gerealiseerd kunnen worden en er op andere locaties percelen worden opgegeven. Dit resulteert in de aanleg van 850 ha nieuw kweekareaal. De schaalgrootte van deze maatregel is van dien aard, dat te verwachten valt dat deze maatregel effect kan hebben op populatieniveau van soorten die aangetrokken worden door de kweekmosselen als habitat in de vorm van hard substraat. De aan mosselen geassocieerde soorten betreffen bodemdieren, maar mogelijk ook vissoorten. In 2018 en 2019 zijn reeds T0 bemonsteringen (beoordeling voor aanleg) voor macrobenthos uitgevoerd en daarmee zijn de bodemdiergemeenschappen voor aanleg van nieuwe percelen in kaart gebracht. De huidige studie is erop gericht in kaart te brengen welke vissoorten in welke dichtheden aanwezig zijn in de gebieden waar nieuwe percelen voorzien zijn, om zo in de toekomst vast te kunnen stellen wat het effect van aanleg geweest is op deze soorten. De voorliggende technische rapportage beschrijft de methode en de voorlopige resultaten van de T0 bemonstering. Nadere analyse en discussie zal plaatsvinden wanneer de bemonsteringen uitgevoerd zijn nadat percelen in gebruik genomen zijn. Naast de aangetroffen vissoorten in de vangsten zijn ook de garnalen, krabben, kreeften, stekelhuidigen (zeesterren) en inktvissen geregistreerd en gerapporteerd. Er zijn vijf perceellocaties bemonsterd: Oosterom, Meep, Inschot in de Vliestroom komberging en Scheurrak en Scheer in de Marsdiep komberging. De bemonstering is uitgevoerd in september 2020 met een combinatie van actieve en passieve vistuigen, omdat elk tuig een bepaalde efficiëntie en selectiviteit heeft. Bovendien verschilt de ondergrond in de T0 en T1, waardoor we nu al rekening moesten houden met de mogelijkheden voor b

WGCATCH contributes to ensure the quality of commercial catch data, which underpins stock assessments and advice. At this year’s WGCATCH meeting all the proposed ToRs were covered and objectives were met. The group started documenting the national estimation procedures (Section 3.2). Most of the countries use ratio estimators for their estimation. Recent discussions at WGCATCH and other EGs have increasingly highlighted that estimation techniques currently used by many countries to process commercial catch data may not be the most up-to-date and/or ignore sampling design and/or are far from transparent and/or involve significant levels of adhoc decisions. Therefore, WGCATCH recommends a series of practical workshops on estimation procedures for the next 3 years to produce best practice guidelines for choosing methods and variables used to raise commercial sampling data. Under ToR a.3, the sample size thresholds used for national data provision were documented. WGCATCH discussed extensively use of specific thresholds, however, it is not possible to come up with a single universal rule to be applied across all countries and stocks. Instead, WGCATCH advises that specific analytical steps are taken during the benchmark process to test and evaluate the impacts of applying or not thresholds to national data before providing the data to the assessment. Intersessional work was carried out to develop tools to be used by the data submitters and stock coordinators to understand and summarise the quality and quantity of the data provided to Intercatch (Section 3.3). The work developed under SSF, ToR b), continued to develop best practice guidelines on SSF data collection, with quantitative analyses on the coverage/completeness of fishing activity. PCA analysis was carried out of data incompleteness issue or over-declaration to build a risk’ map where each country*area is positioned (Section 4.2). The sub-group reviewed the proposed CL and CE data formats from RDBES cor

The Lesser Black-backed Gull, Larus fuscus Linnaeus, 1758, is a surface feeder with a broad prey spectrum that forages in the North Sea on subsurface pelagic fishes and crabs swimming within 0.6 m of the sea surface. In July 2006 and in July/August 2009, we surveyed the Frisian Front area in the southern North Sea (53.4°N–54.3°N, 4.0°E–5.5°E) to determine the prey base for Lesser Black-backed Gulls. In July/August 2009, we conducted bird counts in an integrated ecosystem survey by simultaneously sampling subsurface pelagic prey by a combination of fishing and echosounding. Lesser Black-backed Gulls make use of facilitated foraging to improve the catchability of their prey. The two most important aids for facilitated foraging by Lesser Black-backed Gull in the Frisian Front were (1) multispecies feeding associations with Common Murre, Uria aalge (Pontoppidan, 1763), and (2) fisheries discarding bycatch and offal. We found that in the top meter of the water column, the natural prey base is large enough to provide for self-foraging; however, Lesser Black-backed Gulls were found to rely mainly on facilitated foraging.

Six Terms of Reference (ToRs; Annex 2) were addressed during the meeting through plenary and subgroups. The 2019 report is structured in the same order as the ToRs. Contributions to ToRs were requested in advance of the meeting and all data submissions were requested via a formal WGBYC/ICES data call (Annex 7). The data call requested data on fishing effort, monitoring effort and protected species (marine mammals, seabirds, reptiles and fish) bycatch incidents in 2017. Of the 24 countries contacted, 20 responded to the data call. Many countries continue to submit data late (one-third) and the quality of the data submissions is variable. The data call referred to bycatch of fish, as per the list provided in Table 1D of the Commission Implementing Decision (EU) 2016/1251 adopting a Multiannual Union Programme (EU-MAP); however, WGBYC this year reviewed this list to create a priority fish bycatch list since many of the species on D1 are commercially caught and other scientific bodies, e.g. ICES expert groups, carry out assessments for these. Member States (MS) reports on the implementation of Regulation 812/2004 during 2017 were reviewed. Most MS continue to monitor protected species bycatch using fisheries observers conducting sampling under the Data Collection Framework (DCF); only a few countries have a dedicated bycatch observer programme. With the upcoming repeal of Regulation 812/2004 in 2019, WGBYC will in future receive its data from monitoring under EU-MAP. Monitoring of smaller vessels (<15m) in the European fleet has to date generally been poor, and sampling designs under EU-MAP need to ensure representative coverage of relevant metiers for protected species bycatch. In 2017, bycatch records from the datacall included 148 cetaceans (5 species); 63 seals ( 4 species), 528 birds (22 species); 97,816 elasmobranchs (49 species) and 15 turtles (2 species) .. Equivalent data from non-EU countries was also received from the USA and Iceland. MS’s compliance with

The Lesser Black-backed Gull (Larus fuscus Linnaeus, 1758) is a surface feeder with a broad prey spectrum that forages in the North Sea on subsurface pelagic fishes and crabs swimming within 0.6 m of the sea surface. In July 2006 and in July/August 2009 we surveyed the Frisian Front area in the southern North Sea (53.4oN-54.3oN 4.0oE-5.5oE) to determine the prey base for Lesser Black-backed Gulls. In July/August 2009 we conducted bird counts in an integrated ecosystem survey by simultaneously sampling subsurface pelagic prey by a combination of fishing and echosounding. Lesser Black-backed Gulls make use of facilitated foraging to improve the catchability of their prey. The two most important aids for facilitated foraging by Lesser Black-backed Gull in the Frisian Front were i) multi-species feeding associations with Common Murre and ii) fisheries discarding bycatch and offal. We found that in the top meter of the water column the natural prey base is large enough to provide for self-foraging, however, Lesser Black-backed Gulls were found to rely mainly on facilitated foraging.

The Working Group of International Pelagic Surveys (WGIPS) met in Santa Cruz, Tenerife, Spain on 14–18 January 2019, under the chairmanship of Bram Couperus, Netherlands and Michael O’Malley, Ireland. This was the first meeting in the multi-annual ToR term. The core objectives of the Expert Group 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 the upcoming 2019 surveys. A session was held in 2019 to assess auxiliary pelagic ecosystem surveying techniques currently used on surveys coordinated by WGIPS. It was decided that this approach will be continued in future meetings during this term whereby results from the auxiliary monitoring of ecosystem components will be presented in a separate session from the standard fishery survey results for the target species. In practice this means that the session planned under Term of Reference (ToR) h for 2019 will be repeated in 2020 and 2021. Additionally, progress, developments and experiences with the survey analysis software StoX as well as with the ICES acoustic database repository were analysed and discussed amongst users and developers during the meeting and the intention to further consolidate both the software and the database as common tools to be utilized among all surveys coordinated within WGIPS was stated. Further work progressed on editing the current version of the SISP 9 Manual for International Pelagic Surveys and will continue intersessionally. WGIPS requests a workshop to establish and agree on survey design and protocols for coordinating and conducting acoustic surveys on herring spawning aggregations. The workshop will focus on industry acoustic surveys on herring spawning aggregations in 6.a and in the Irish Sea. WGIPS also requests a workshop o

Suppleties van zand op vooroever of strand worden in opdracht van Rijkswaterstaat uitgevoerd om de Nederlandse kust tegen erosie te beschermen en om voldoende zand in het kustfundament te houden. Een groot deel van de suppleties vindt plaats in of nabij de kuststrook die binnen de Natura2000 regelgeving wordt beschermd, de Noordzeekustzone. Het is dus van belang de eventuele effecten van deze praktijk op de natuur zorgvuldig te bestuderen, zodat dit effect kan worden afgezet tegenover het algemene nut voor de maatschappij. Betere kennis van de effecten kan leiden tot beperking van eventuele schade aan- en mogelijk zelfs tot versterking van- gewenste natuurwaarden en ecosysteemdiensten. Tot nog toe is er relatief weinig aandacht geweest voor de gevolgen van suppleren op vispopulaties in vergelijking met benthos, terwijl de kinderkamerfunctie van de ondiepe kustzone een zeer belangrijke economische ecosysteemdienst levert. Kennis van de habitatfactoren die het voorkomen van juveniele vis in kinderkamers bepalen leidt tot een verbeterd inzicht van de gevolgen van suppleties op vispopulaties en van de voedselketen van viseters in de ondiepe kustzone. In overleg met natuurorganisaties en de kennisinstituten Deltares en Wageningen Marine Research is in 2016 het document `Ecologische effecten van zandsuppleties’ (Herman et al., 2016) geschreven met als doel onderzoek te formuleren naar ecologische effecten van zandsuppleties. In het onderdeel ‘uitvoeringsplan’ (deel C in Herman et al. 2016) zijn 3 onderzoekslijnen (ook wel Krachtlijnen genoemd) gedefinieerd, te weten: Vooroever, Duinen en Waddenzee. Het hier beschreven meetplan voor een survey in 2017 valt onder de onderzoekslijn Vooroever. De onderzoeksvraag die in dit meetplan wordt behandeld volgt uit de prioritering van de krachtlijn Vooroever: (Cumulatieve) gevolgen van reguliere suppleties op samenstelling en functioneren van het ecosysteem van de vooroever. Deze onderzoeksvraag luidt: “Wat zijn de cumulatieve gevolg