• Aran, Galway Bay and Slyne Head Nephrops Grounds (FU17) 2021UWTV Survey Report and catch scenarios for 2022

      Aristegui, M.; Doyle, J.; Ryan, G.; Fitzgerald, R.; White, Jonathan; O’ Brien, S.; Tully, D.; Sullivan, M. (Marine Institute, 2021)
      This report provides the main results and findings of the twentieth annual underwater television survey on the Aran, Galway Bay and Slyne head Nephrops grounds, ICES assessment area; Functional Unit 17. The survey was multi-disciplinary in nature collecting UWTV, CTD and other ecosystem data. In 2021 a total of 44 UWTV stations were successfully completed, 34 on the Aran Grounds, 5 on Galway Bay and 5 on Slyne Head patches. The mean burrow density observed in 2021, adjusted for edge effect, was medium at 0.26 burrows/m². The final krigged burrow abundance estimate for the Aran Grounds was 311 million burrows with a CV (Coefficient of Variance; relative standard error) of 4%. The final abundance estimate for Galway Bay was 12 million and for Slyne Head was 9 million, with CVs of 2% and 2% respectively. The total abundance estimates have fluctuated considerably over the time series. The 2021 combined abundance estimate (331 million burrows) is 16% lower than in 2020, the MSY Btrigger reference and it is below point (540 million burrows). Using the 2021 estimate of abundance and updated stock data imply that catches in 2022 should be no more than 360 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 2018–2020. Virgularia mirabilis was the only sea-pen species observed on the UWTV footage. Trawl marks were present at 5% of the Aran stations surveyed.
    • Cruise report: Irish Anglerfish & Megrim Survey 2020

      Kelly, Eoghan; Gerritsen, Hans D; Coleman, Paul; Stokes, David; O’ Brien, S.; White, Jonathan; Aristegui, M.; O’Connor, Sean (Marine Institute, 2020)
      The 2020 Irish Anglerfish and Megrim Survey (IAMS) took place from 23rd February to 18th March (area 7bcjk) and 12-21st April 2020 (area 6a) on RV Celtic Explorer. The main objective of the survey is to obtain biomass and abundance indices for anglerfish (Lophius piscatorius and L. budegassa) and megrim (Lepidorhombus whiffiagonis and L. boscii) in areas 6a (south of 58°N) and 7 (west of 8°W). Secondary objectives are to collect data on the distribution, relative abundance and biology of other commercially exploited species. For the second year, additional sampling took place in deep water (up to 1,500m) in order to monitor the recovery of exploited deep-water species following the decline of the deep-water fisheries in Irish waters. The IAMS survey is coordinated with the Scottish Anglerfish and Megrim Survey (SIAMISS) and uses the same gear and fishing practices.
    • FU19 Nephrops Grounds 2021 UWTV Survey Report and catch scenarios for 2022

      Doyle, Jennifer; Ryan, G; Aristegui, M.; Fitzgerald, Ross; Tully, D.; O’Brien, S.; White, Jonathan; Sullivan, M.; Lynch, Deirdre; McAuliffe, M (Marine Institute, 2021)
      This report provides the main results of the twelfth underwater television survey of the various Nephrops patches in Functional Unit 19. The survey was multi-disciplinary in nature collecting UWTV and other ecosystem data. In 2021 a total 42 UWTV stations were successfully completed. The mean density estimates varied considerably across the different patches. The 2021 raised abundance estimate was a 16% decrease from the 2020 estimate and at 270 million burrows is below the MSY Btrigger reference point (430 million). Using the 2021 estimate of abundance and updated stock data implies catch in 2022 that correspond to the F ranges in the EU multi annual plan for Western Waters are between 363 and 407 tonnes (assuming that discard rates and fishery selection patterns do not change from the average of 2018–2020). One species of sea pen were observed; Virgularia mirabilis which has been observed on previous surveys of FU19. Trawl marks were observed at 19% of the stations surveyed.
    • The Labadie, Jones and Cockburn Banks Nephrops Grounds (FU2021) 2021 UWTV Survey Report and catch scenarios for 2022.

      Doyle, Jennifer; Ryan, G.; Aristegui, M.; Fitzgerald, Ross; Tully, D.; O'Brien, S.; White, Jonathan; Sullivan, M.; Lynch, Deirdre; McAuliffe, M (Marine Institute, 2021)
      This report provides the main results of the 2021 underwater television survey on the ‘Labadie, Jones and Cockburn Banks’ ICES assessment area; Functional Unit 2021. The 2021 survey was multi-disciplinary in nature collecting UWTV and other ecosystem data. A total of 97 UWTV stations were completed at 6 nm intervals over a randomised isometric grid design. The mean burrow density was 0.12 burrows/m2 compared with 0.102 burrows/m2 in 2020. The 2021 geostatistical abundance estimate was 1202 million, a 18% increase on the abundance from 2020, with a CV of 5%, which is well below the upper limit of 20% recommended by SGNEPS 2012. Low to medium densities were observed throughout the ground. Using the 2021 estimate of abundance and updated stock data implies catch in 2022 that correspond to the ICES MSY approach of 1978 tonnes assuming that discard rates and fishery selection patterns do not change from the average of 2018–2020. One species of sea-pen (Virgularia mirabilis) were recorded as present at the stations surveyed. Trawl marks were observed at 21% of the stations surveyed.
    • The “Smalls” Nephrops Grounds (FU22) 2021 UWTV Survey Report and catch scenarios for 2022

      Aristegui, M.; Fitzgerald, Ross; Lynch, Deirdre; White, Jonathan; Doyle, Jennifer; McAuliffe, M (Marine Institute, 2021)
      This report provides the main results and findings of the sixteenth annual underwater television survey on the ‘Smalls grounds’ ICES assessment area; Functional Unit 22. The survey was multi-disciplinary in nature collecting UWTV and other ecosystem data. A total of 42 UWTV stations were surveyed successfully (high quality image data), carried out over an isometric grid at 4.5nmi or 8.3km intervals. The precision, with a CV of 7%, was well below the upper limit of 20% recommended by SGNEPS (ICES, 2012). The 2021 abundance estimate was 13% lower than in 2020 and at 656 million is below the MSY Btrigger reference point (990 million). Using the 2021 estimate of abundance and updated stock data implies catch in 2022 that correspond to the ICES MSY approach of 1257 tonnes assuming that discard rates and fishery selection patterns do not change from the average of 2018–2020. One species of sea pen was recorded as present at the stations surveyed: Virgularia mirabilis. Trawl marks were observed at 24% of the stations surveyed.