Library
Back to ICES Scientific Reports

Working Group on Beam Trawl Surveys (WGBEAM)

ICES
2020

Record created 10/06/2020 | Last updated 10/06/2020
ICES Scientific Reports volume 2, issue 48
DOI: https://doi.org/10.17895/ices.pub.6028

Abstract

The Working Group on Beam Trawl Surveys (WGBEAM) plans, coordinates, and implements European inshore and offshore beam trawl surveys. The group’s activities relate mostly to the role of the group, i.e. to coordinate beam trawl surveys in the ICES area, including planning, standardization, data transmission and data quality assurance. The 2019 inshore and offshore beam trawl survey data for North Sea (subarea 4) and Western Waters (subareas 7 and 8) have been uploaded to the ICES dataportal DATRAS, and are available for the stock assessments. In the North Sea as well as in division 7d, the strong 2018 cohort for both plaice and sole is still visible as 1-year old. For plaice, the 1-year olds are mainly visible in the offshore surveys (BTS), for sole the 2018 cohort is well visible in both the offshore and the inshore survey indices. Annually, an update assessment is carried out for sole in autumn, using the Dutch BTS data in the southeastern North Sea of the running year. Generally, it is to be expected that the signal from that survey is incomplete to provide a proper forecast based on the 1-year olds in the survey year, because the inshore surveys are still running at the time of the update assessment. As in the past years, the data delivery deadlines for the update assessment for plaice and sole could only nearly be met. WGBEAM has discussed this issue and proposes achievable deadlines for data delivery based on the processing time (technical sample and data processing combined with the time available beside other workflows in the institute), and including sufficient time for qual-ity checks, for both the offshore and the inshore beam trawl surveys. The planning for the 2020 surveys has been completed, including an overview of rectangles for comparative fishing during the German and Dutch North Sea beam trawl surveys. An outline was created for the Manual on inshore beam trawl surveys, including intersessional actions to be taken. Updates to the Manual on offshore beam trawl surveys have been added and a full update is scheduled for 2022. During the meeting R scripts for data consistency checks were developed. Although not final-ized, it is proposed that the scripts are stored at a WGBEAM GitHub to facilitate versioned scripts and to support efficient workflows and processing of similar data.