ICES coordinated acoustic survey of ICES divisions IIIa, IVa, IVb AND Via (North) 2002 Results and long term trends

Six surveys were carried out during late June and July covering most of the continental shelf north of 54oN in the North Sea and to the west of Scotland to a northern limit of 62oN. The eastern edge of the survey area was bounded by the Norwegian and Danish, Swedish and German coasts, and to the west by the shelf edge between 200 and 400 m depth. The surveys are reported individually in the report of the planning group for herring surveys, and a combined report has been prepared from the data from all surveys. The combined survey results provide spatial distributions of herring abundance by number and biomass at age by statistical rectangle; and distributions of mean weight and fraction mature at age. The estimates of North Sea autumn spawning herring are consistent with previous years at 2.9 million tonnes and 17,200 million herring. The survey also shows two exceptional year classes of herring (the 1998 and 2000 year classes) in the North Sea, which is consistent with the observation of exceptionally large year classes observed in the MIK and IBTS surveys. The estimates of Western Baltic spring spawning herring SSB are 255,000 tonnes and 2.9 millions (Table 2) and show a large increase compared with the previous year. The Western Baltic survey produces a rather noisy signal but the indications are of a stock that is higher now than between 1996 to 2000. The West of Scotland survey estimates of 548,000 tonnes and 2,900 million and shows the high 1995 year class again this year. The 1998 year class now (3 ring) is also a large one. Total adult mortality shows much lower mortality than last year (0.1 compared to 0.5 ) but the mean mortality over the last 4 years has been 0.3: this is consistent with the 2002 assessment that the stock is lightly exploited. The overall time series of abundance by age from 1989 to 2002 are summarised by simple models describing the spatial distribution over time. The changes over time with latitude, longitude and area occupied are compared with changes in abundance

ICES coordinated acoustic survey of ICES divisions IIIa, IVa, IVb AND Via (North) 2002 Results and long term trends

Six surveys were carried out during late June and July covering most of the continental shelf north of 54oN in the North Sea and to the west of Scotland to a northern limit of 62oN. The eastern edge of the survey area was bounded by the Norwegian and Danish, Swedish and German coasts, and to the west by the shelf edge between 200 and 400 m depth. The surveys are reported individually in the report of the planning group for herring surveys, and a combined report has been prepared from the data from all surveys. The combined survey results provide spatial distributions of herring abundance by number and biomass at age by statistical rectangle; and distributions of mean weight and fraction mature at age. The estimates of North Sea autumn spawning herring are consistent with previous years at 2.9 million tonnes and 17,200 million herring. The survey also shows two exceptional year classes of herring (the 1998 and 2000 year classes) in the North Sea, which is consistent with the observation of exceptionally large year classes observed in the MIK and IBTS surveys. The estimates of Western Baltic spring spawning herring SSB are 255,000 tonnes and 2.9 millions (Table 2) and show a large increase compared with the previous year. The Western Baltic survey produces a rather noisy signal but the indications are of a stock that is higher now than between 1996 to 2000. The West of Scotland survey estimates of 548,000 tonnes and 2,900 million and shows the high 1995 year class again this year. The 1998 year class now (3 ring) is also a large one. Total adult mortality shows much lower mortality than last year (0.1 compared to 0.5 ) but the mean mortality over the last 4 years has been 0.3: this is consistent with the 2002 assessment that the stock is lightly exploited. The overall time series of abundance by age from 1989 to 2002 are summarised by simple models describing the spatial distribution over time. The changes over time with latitude, longitude and area occupied are compared with changes in abundance

Workshop on fish of conservation and bycatch relevance (WKCOFIBYC)

WKCOFIBYC was convened to develop a list of species of conservation and/or bycatch interest, that could be used to prioritize and plan for future work within ICES. WKCOFIBYC compiled a list of fish species (including non-commercial and commercial) of conservation concern (threatened, sensitive, or already listed in legislation) that could be included in future assessments by ICES. This is termed the Comprehensive Species List (CSL). This list is composed of international and national hard law, along with national hard law designations, in addition to relevant red lists of extinction risk and various academic exercises to identify sensitive species. Through the work of WKCOFIBYC, for the first time, lists of priority sensitive species for future conservation/biodiversity-concern assessment have been developed: the regional assessment lists (RALs). The workshop also compiled ecoregion-level lists (regional bycatch lists or RBLs) of fish species of bycatch concern, which can be used for future planning. To avoid duplication, the RALs and RBLs exclude species for which ICES or other bodies already provide quantitative assessments. Additionally, the RBLs exclude most remaining species already advised upon by ICES or equivalent bodies. A set of guidelines for establishing assessment units are presented in the report. This process started by identifying over 4501 species from the Northeast Atlantic and the Mediterranean, including some brackish water and diadromous species, from the ‘Lists of Fishes of Conservation Interest’. However, 1282 of these species were deemed not relevant, mainly due to not being representative of the main fish fauna of the regions (as determined by regional experts)3. The list is structured by relevance, geography, and according to which legal, scientific, or other designations of being sensitive to overexploitation were relevant. The ICES ecoregions or Mediterranean subregions where the species occur are indicated. Also, the listing of each species in hard and soft law is noted. Hard law includes the EU Habitats Directive, the Common Fisheries Policy Prohibited Species list, and (where EU law may not apply)4 national legislation in the UK and Iceland. Where species are listed in various Red Lists of extinction risk, this is also noted. The methodology by which the lists were compiled is provided. A key challenge for ICES will be to maintain the list and ensure it remains current. As WKCOFIBYC is a one-off initiative, it remains unclear how the lists will be maintained going forward. The attention of ACOM is drawn to this matter

Workshop on estimation of mortality of marine mammals due to bycatch (WKMOMA)

The Workshop on estimation of MOrtality of Marine MAmmals due to Bycatch (WKMOMA) addressed a special request from OSPAR regarding the bycatch mortality of marine mammals (harbour porpoise Phocoena phocoena; common dolphin Delphinus delphis; and grey seal Halicho-erus grypus) within the OSPAR maritime area. The objective of the workshop was to generate bycatch rates and associated confidence intervals for static and towed gears for relevant species within the three species assessment areas defined by OSPAR. Subsequently, the species-specific bycatch mortality estimates in the defined assessment area were requested. OSPAR provided thresholds for the relevant species/assessment units and ICES were tasked to compare the mortality estimates to the provided thresholds and identify any critical issues relevant for the comparison

Third workshop on appropriate sampling schemes for protected, endangered and threatened species bycatch (WKPETSAMP3)

The workshops WKPETSAMP2 and WKPETSAMP3 were convened following a special request from the European Union’s Directorate-General for Environment (DG ENV) on appropriate sampling schemes for endangered, threatened and protected (ETP) species. In particular, these workshops were tasked with providing concrete inputs and results to inform ICES advice to DG ENV on ‘appropriate bycatch monitoring systems at Member State level and on regional coordination’. An aim of the PETSAMP workshops was to generate improved insights into how aspects of sampling design may impact the precision and accuracy of bycatch estimates and the detection probability of bycatch events. The workshop considered key issues such as: how sampling coverage (percentage of monitored fishing operations) impacts the precision of bycatch estimates and how this is dependent on the bycatch probability (how often a bycatch is encountered); if stratification improves precision and if this is dependent on bycatch probability; if it is better to sample few vessels but many trips (e.g. typical of reference fleets and Electronic Monitoring programmes) or many vessels but fewer trips (e.g. typical of at-sea observer programmes). To do this the WKPETSAMP2 extended the simulation framework (SCOTI) developed by WGBYC in 2022. This framework was used in WKPETSAMP3 and was parameterized with data from several case studies. The case studies are from ongoing or historical sampling programs and represent different waters across Europe and different fisheries

Working group on bycatch of protected species (WGBYC 2021)

The Working Group on Bycatch of Protected Species (WGBYC) was established in 2007 and collates and analyses information from across the Northeast Atlantic and adjacent sea areas (Baltic, Mediterranean and Black Seas) related to the bycatch of marine mammals, seabirds, turtles, and sensitive fish species in commercial fishing operations. Sensitive fish species were not considered at the 2021 meeting pending approval from the ICES Advisory Committee (ACOM) on fish species lists of bycatch interest that were developed at the ICES Workshop on Fish of Conservation and Bycatch Relevance (WKCOFIBYC) in 2020. WGBYC seeks to describe and improve under-standing of the likely impacts of fishing activities on affected populations at biologically relevant scales, to inform on the suitability of existing at-sea monitoring programmes for the quantification of robust bycatch estimates, and to collate information on and coordinate bycatch mitigation efforts at an international scale. In 2021, the WG met by correspondence to address eight Terms of Reference (ToR), including a data scoping exercise as part of a special request on seabird bycatch from the North East Atlantic Fisheries Commission (NEAFC), which concluded that there was insufficient bycatch monitoring data from NEAFC waters to warrant further analyses at this time. The report also provides an overview of monitoring and fishing effort data contained in the WGBYC database for 2019 and 2020. This showed that during 2020, in most geographical areas of relevance, at-sea monitoring effort was significantly affected by the Covid-19 pandemic. Specific analyses were carried out to describe potential fisheries impacts (reported bycatch numbers, min/max bycatch rates and/or mortality estimates) for harbour seal in the Greater North Sea ecoregion and parts of the Baltic ecoregion, three turtle species in four Mediterranean ecoregions and in the Azores and Bay of Biscay and Iberian Coast ecoregions, and several seabird species in six ecoregions (Adriatic, Baltic, Bay of Biscay and Iberian Coast, Celtic Seas, Greater North Sea and Icelandic Waters). A risk-based approach, developed by WGBYC in 2020 to highlight monitoring gaps, was expanded using information from multiple sources and identified several high-risk métiers for bycatch which are relatively under-sampled by existing data collection programmes. Several members of WGBYC also participated simultaneously in the ICES Workshop on Estimation of Mortality of Marine Mammals due to Bycatch (WKMOMA) which ran over schedule due to data issues. Data used by WGBYC on fishing effort, at-sea monitoring effort and bycatch records are primarily acquired through an ICES dedicated data call which has been issued annually to all ICES member states since 2018 and all non-ICES EU coastal states from 2021. Although data quality and quantity are improving, WGBYC reiterate that significant gaps remain in data collection efforts and in data resolution, that limits the Working Group’s ability to provide useful assessments of the likely impacts of fishing activity across a wide range of protected species and areas. WGBYC note that broadscale low level monitoring programmes may be insufficient to highlight very rare bycatch occurrences for populations at low abundance and/or low susceptibility to by-catch, but which could have significant population levels impacts