Working Group on Nephrops Surveys (WGNEPS outputs from 2021)

183 pages, figures, 6 annexesThe Working Group on Nephrops Surveys (WGNEPS) is the international coordination group for Nephrops underwater television and trawl surveys within ICES. This report summarizes the national contributions on the results of the surveys conducted in 2021 together with time series covering all survey years, problems encountered, data quality checks and technological improvements as well as the planning for survey activities for 2022. In total, 19 surveys covering 25 functional units (FU’s) in the ICES area and 1 geographical sub- area (GSA) in the Adriatic Sea were discussed and further improvements in respect to survey design and data analysis standardization and the use of recent technologies were reviewed. Due to the COVID-19 pandemic there were minimal disruptions to survey operations where one survey was not completed (GSA 17). A trial trawl Nephrops survey offshore Portugal was carried out on the new research vessel. Preliminary work on how to measure burrow system size was presented using high definition (HD) and standard definition (SD) image data. Further work on comparison of SD and HD indi- cates the change to HD system mounted with a different camera angle was not significantly different for two survey areas (FU 16 and FU 20-21). Automatic burrow detection based on deep learning methods continues to show promising re- sults where datasets from multiple institutes were used. The working group members have agreed to draft a roadmap for automatic system technology requirements with links to the Work- ing Group on Machine Learning in Marine Science (WGMLEARN) and current researchers. The working group is progressing plans for an international Nephrops Underwater television (UWTW) database to be established at the ICES Data Centre. End-users of UWTV datasets for epifauna reporting presented their work and showed the potential for adding value to the survey data, where many of the institutes are involved in providing data for similar research purposesPeer reviewe