Aran, Galway Bay and Slyne Head Nephrops Grounds (FU17) 2022 UWTV Survey Report and catch scenarios for 2023

Abstract

This report provides the main results and findings of the 21st annual underwater television survey on the Aran, Galway Bay and Slyne head Nephrops grounds, ICES assessment area; Functional Unit 17. In 2022, due to disruption to the survey schedule caused by weather downtime, the UWTV survey could not complete the Aran Grounds and Slyne Head stations, and was only able to complete successfully the 5 Galway Bay stations. The survey was multi-disciplinary in nature collecting UWTV, CTD and other ecosystem data. The mean burrow density observed in Galway Bay, adjusted for edge effect, was 0.19 burrows/m2; and the final abundance estimate for this ground was 15 million burrows with a CV (Coefficient of Variance; relative standard error) of 3%. There were no sea-pen species nor trawl marks observed in the footage from Galway Bay. The 2022 UWTV survey was not deemed robust enough to derive fishing advice for 2023 owing to the reduced number of stations. As such, the stock size is considered unknown for 2022. Therefore, the assessment and catch advice for 2023 is based on the 2021 UWTV survey. The 2021 combined abundance estimate (331 million burrows) was below the MSY Btrigger reference (540 million burrows). Using the 2021 estimate of abundance and updated stock data imply that catches in 2023 should be no more than 363 tonnes, according to the EU MAP and ICES MSY approach and assuming that discard rates and fishery selection patterns do not change from the average of 2019–2021.