Working Group on Beam Trawl Surveys (WGBEAM)

The Working Group on Beam Trawl Surveys (WGBEAM) coordinates and implements European inshore and offshore beam trawl surveys, including planning, standardization, data transmission and data quality assurance. The group also coordinates the Italian/Croatian/Slovenian beam trawl survey in the Adriatic Sea as there is no other body in the EU coordinating beam trawl surveys, and the EU Data Collection Framework requires survey coordination. In 2021, eleven beam trawl surveys were planned, covering the North Sea, 7d, 7e, 7fg, 7a, 8a, 8b and the Northern Adriatic Sea. Despite the COVID-19 pandemic, most surveys could be carried out according to schedule, but sometimes with less staff, or leaving out some part of the sampling, e.g. limited marine litter data collection in German offshore survey. All data have been transmitted to the ICES Database of Trawl Surveys (DATRAS). The German inshore survey was conducted by commercial shrimp vessels due to technical issues with the research vessel. Shortly before the end of the survey one of the commercial vessels sank, and the remainder of the survey (3 more days) was cancelled. A new hermit crab species for the North Sea was encountered (Pagurus longicarpus) in the German inshore survey. In 2022, a combined session with North Sea and Celtic Sea stock coordinators took place where all surveys were presented. Stock coordinators discussed developments in data use and provided an overview of current beam trawl survey data use in the assessments. Main topics that arose from this session were the request for additional age data collection on witch flounder (Glyptocephalus cynoglossus) and a further investigation of the changing maturation and growth patterns in plaice (Pleuronectes platessa). The 2018 cohort for sole (Solea solea) and plaice (Pleuronectes platessa) in the North Sea and 7d is still visible as 3-year olds in the 2021 beam trawl surveys. No additional strong year classes could be seen for sole and plaice. R scripts to evaluate the combined offshore and inshore beam trawl surveys data by region and cross-regionally have been further developed, and a preferred calculation method for swept area has been created. Specific analyses have been conducted on elasmobranchs (patterns in abundance and spatial distribution), brown shrimp Crangon crangon (numbers measured and length ranges by survey), and marine litter (consistency in reporting). The manual for the offshore beam trawl surveys has been updated and made ready for publication in 2022. The manual for the inshore beam trawl surveys has been further developed towards a final draft, to be finalised in autumn 2022.