Flapper skate

Dipturus intermedius

5: Avoid How we work out the ratings

What to check for

Location

North Sea and Skagerrak; Celtic Sea and West of Scotland

Technical location

Atlantic, Northeast, Irish Sea, Porcupine Bank, English Channel, Bristol Channel, Celtic Seas, West and Southwest of Ireland, Rockall, West of Scotland

Caught by

Bottom trawl (beam), Bottom trawl (otter), Net (gill or fixed)

Rating summary

It is prohibited to fish for, land, or retain blue and flapper skate in UK or EU waters. Very little is know about the stock, but both species are assessed as Critically Endangered by IUCN and are listed by OSPAR as a threatened and declining species. Therefore, they are automatically a red-rated species.Rating last updated October 2023.

Technical consultation summary

How we worked out this Rating

It is prohibited to catch blue and flapper skate across this area of Europe. Therefore, it is a critical fail on the Good Fish Guide.There are a lack of reference points for the stock, which prevents the development of management plans. ICES advises that the collection of species-specific landings data should be introduced for more species of rays and skates to help inform on the status of these stocks. However, species-specific quotas may increase misreporting or discarding.Current UK and EU regulations prohibit the fishing, retention on board, transshipping, or landing of the common skate complex (blue skate and flapper skate). This prohibition applies to UK and EU waters of ICES Division 2.a and subareas 3-4 and 6-10. The species’ are also on The UK List of Priority Species and Habitats and have been listed as priorities for conservation action under the UK Biodiversity Action Plan (UK BAP). The Plan aims to stabilise populations by minimising fishing mortality and legally protect it in at least 5 key areas. The Loch Sunart to the Sound of Jura Marine Conservation Order lists “common skate” as the designation feature of this MPA which should reduce fishing mortality and maintain habitat in an important area for the species.Identification of skate and ray species at the point of sale is difficult as they are commercially valued for their wings and so the bodies are often discarded and the wings skinned. However, DNA analysis of skate wings on sale in the UK suggests that blue and flapper skate do not often reach the market. Landings for both flapper and blue skate are reported, however, they are often misidentified and recorded as Norwegian skate or longnosed skate.The Skate Working Group and OSPAR highlight the need to build on and develop a greater understanding of the species’ current distributions and critical habitat to inform future management options. Additionally, flapper skate may be more vulnerable to overfishing which highlights the need to monitor and assess these two species separately.Skates and rays caught in the Northwest waters (ICES subareas 6 and 7) and North Sea waters (ICES subareas 2a, 3a and 4) with all fishing gears, are exempt from the landing obligation, based on their high survivability rates. Any skates and rays that are discarded are required to be released immediately and below the sea surface.Both the EU and UK have fishery management measures in place, which can include catch limits, targets for population sizes and fishing mortality, and controls on what fishing gear can be used and where. In the EU, compliance with regulations has been variable, and there are ongoing challenges with implementing some of them. There was a target for fishing to be at Maximum Sustainable Yield by 2020, but this was not achieved.In the UK, it is too early to tell how effective management is, as the Fisheries Act only came into force in January 2021. The Act requires the development of Fisheries Management Plans (FMPs) (replacing EU Multi-Annual Plans) but there are no details yet on how and when these will be developed. FMPs have the potential to be very important tools for managing UK fisheries, although data limitations may delay them for some stocks. MCS is keen to see FMPs for all commercially exploited stocks, especially where stocks are depleted, that include:Targets for fishing pressure and biomass, and additional management when those targets are not being metTimeframes for stock recoveryTechnologies such as Remote Electronic Monitoring (REM) to support data collection and improve transparency and accountabilityConsideration of wider environmental impacts of the fishery

References

Dedman, S., Officer, R. Brophy, D., Clarke, M. Reid, D. G. 2017. Towards a flexible Decision Support Tool for MSY-based Marine Protected Area design for skates and rays, ICES, 74 (2) pp. 576-587. Available at https://academic.oup.com/icesjms/article/74/2/576/2669563 [Accessed on 04.10.2023].Eigaard, O.R., Bastardie, F., Breen, M., Dinesen, G.E., Hintzen, N.T., Laffargue, P., Mortensen, L.O., Nielsen, J.R., Nilsson, H.C., O'Neill, F.G., Polet, H., Reid, D.G., Sala, A., Sköld, M., Smith, C., Sorensen, T.K., Tully, O., Zengin, M., Rijnsdorp, A.D., 2016. Estimating seabed pressure from demersal trawls, seines, and dredges based on gear design and dimensions. ICES Journal of Marine Science, Volume 73, Issue suppl 1. Pages i27-i43. Available at https://academic.oup.com/icesjms/article/73/suppl_1/i27/2573989 [Accessed on 04.10.2023].Ellis, J.R., McCully-Philipps, S.R., Sims, D., Walls, R.H.L., Cheok, J., Derrick, D., et al., 2021. Dipturus intermedius. The IUCN Red List of Threatened Species 2021: e.T18903491A68783461. Available at https://dx.doi.org/10.2305/IUCN.UK.2021-2.RLTS.T18903491A68783461.en. [Accessed on 11.10.2023].Ellis J., McCully-Philipps, S.R., Sims, D., Derrick, D., Cheok, J., Dulvy, N.K., 2021. Dipturus batis. The IUCN Red List of Threatened Species 2021: e.T203364219A203375487. Available at https://dx.doi.org/10.2305/IUCN.UK.2021-2.RLTS.T203364219A203375487.en. [Accessed on 11.10.2023].Ellis, J. R., Burt, G.J., Grilli, G., McCully Phillips, S.R., Catchpole, T.L., Maxwell, D.L. 2018. At-vessel mortality of skates (Rajidae) taken in coastal fisheries and evidence of longer-term survival. Journal of Fish Biology. 92, 1702-1719. Available at https://pubmed.ncbi.nlm.nih.gov/29675895/ [Accessed on 04.10.2023].Fowler, S., Mogensen, C.B. and Blasdale, T., 2004. Plan of Action for the Conservation and Management of Sharks in UK Waters. JNCC Report No. 360. Available at https://data.jncc.gov.uk/data/1db13bd9-ead2-4b22-a965-99de5de1c457/JNCC-Report-360-FINAL-WEB.pdf [Accessed on 10.10.2023].Froese, R. and Pauly, D. (Editors), 2023. Blue skate - Dipturus batis. Available at https://www.fishbase.se/Summary/SpeciesSummary.php?ID=2058&AT=blue+skate [Accessed on 11.10.2023].Froese, R. and Pauly, D. (Editors), 2023. Flapper skate, Dipturus intermedius – Fishbase. Available at https://www.fishbase.se/summary/Dipturus-intermedius.html [Accessed on 11.10.2023].Frost M, Neat FC, Stirling D, Bendall V, Noble LR, Jones CS., 2020. Distribution and thermal niche of the common skate species complex in the north-east Atlantic. Mar Ecol Prog Ser, 656:65–74.Garbett A, Phillips ND, Houghton JDR, Prodöhl P, Thorburn J, Loca SL, et al., 2021. The critically endangered flapper skate (Dipturus intermedius): Recommendations from the first flapper skate working group meeting. Mar Policy: 1;124:104367.Griffiths AM, Sims DW, Cotterell SP, El Nagar A, Ellis JR, Lynghammar A, et al. 2010. Molecular markers reveal spatially segregated cryptic species in a critically endangered fish, the common skate (Dipturus batis). Proc R Soc B Biol Sci 277(1687):1497–503.Hiddink, J., Jennings, S., Sciberras, M., Szostek, C.L., Hughes, K.M., Ellis, N., Rijnsdorp, A.D., McConnaughey, R.A., Mazor, T., Hilborn, R., Collie, J.S., Pitcher, C.R., Amoroso, R.O., Parma, A.M., Suuronen, P. and Kaiser, M.J. 2017. Global analysis of depletion and recovery of seabed biota after bottom trawling disturbance. PNAS. 114:31, pp. 8301-8306. Available at https://doi.org/10.1073/pnas.1618858114 [Accessed on 04.10.2023].ICES. 2022. Common skate complex (blue skate [Dipturus batis] and flapper skate [Dipturus intermedius]) in Subarea 6 and divisions 7.a–c and 7.e–k (Celtic Seas and western English Channel). In Report of the ICES Advisory Committee, 2022. ICES Advice 2022, rju.27.67a-ce-k. Available at https://doi.org/10.17895/ices.advice.19754416 [Accessed on 10.11.2023].ICES. 2022. Working Group on Elasmobranch Fishes(WGEF).ICES Scientific Reports. 4:74. 848pp. Available at http://doi.org/10.17895/ices.pub.21089833 [Accessed on 04.10.2023].Kennelly, S. J. & Broadhurst, M. K., 2021. A review of bycatch reduction in demersal fish trawls. Rev Fish Biol Fisheries 31, 289–318. Available at https://doi.org/10.1007/s11160-021-09644-0. [Accessed on 04.10.2023].Kynoch, R., Fryer, R. & Neat, F., 2015. A simple technical measure to reduce bycatch and discard of skates and sharks in mixed-species bottom-trawl fisheries. ICES J Mar Sci,72(6):1861. Available at https://academic.oup.com/icesjms/article/72/6/1861/921176 [Accessed on 04.10.2023].Mangi, S., Kupschus, S., Mackinson, S., Rodmell, D., Lee, A., Bourke, E., Rossiter, T., Masters, J., Hetherington, S., Catchpole, T. and Righton, D. 2018. Progress in designing and delivering effective fishing industry science data collection in the UK. Fish 00:1-21. Available at https://onlinelibrary.wiley.com/doi/10.1111/faf.12279 [Accessed on 04.10.2023].Peverley. M., Stewart, J.E., 2021. Fisheries Research & Management Plan: Skates & Rays in the North of Devon and Severn IFCA’s District. Devon and Severn Inshore Fisheries and Conservation Authority & North Devon Biosphere.. Available from: https://www.devonandsevernifca.gov.uk/Environment-and-Research/Fisheries-Research-Management-Plans/FRMP-Documents [Accessed on 10.10.2023].Shark Trust. 2023. Fisheries Advisories. Available at https://www.sharktrust.org/pages/category/fisheries-advisories [Accessed on 04.10.2023].Shephard, S. Reid, D.G.,Gerritsen, H.D, Farnsworth, K.D. Estimating biomass, fishing mortality, and total allowable discards for surveyed non-target fish, ICES Journal of Marine Science, Volume 72, Issue 2, 1 January 2015, Pages 458-466. Available at https://academic.oup.com/icesjms/article/72/2/458/2801434 [Accessed on 04.10.2023].Silva, F., Ellis, J. & Catchpole, T., 2012. Species composition of skates (Rajidae) in commercial fisheries around the British Isles and their discarding patterns. J Fish Biol., 80:1678–1703. Available at https://www.nwwac.org/_fileupload/Papers%20and%20Presentations/2016/06%20FG%20Skates%20and%20Rays/Silva,%20Ellis%20&%20Catchpole_2012_Skate%20catches.pdf [Accessed on 04.10.2023].Sguotti, C., Lynam, C. P., Garcia-Carreras, B., Ellis, J. R. and Engelhard, G. H. 2016. Distribution of skates and sharks in the North Sea: 112 years of change. Glob Change Biol, 22: 2729-2743. doi:10.1111/gcb.13316. Available at https://onlinelibrary.wiley.com/doi/full/10.1111/gcb.13316 [Accessed 04.10.2023].Thorburn J., Dodd J., Neat F., 2018. Spatial ecology of flapper skate (Dipturus intermedius-Dipturus batis complex) and spurdog (Squalus acanthias) in relation to the Loch Sunart to the Sound of Jura Marine Protected Area and Loch Etive.van Denderen, P. Bolam, S., Hiddink, J.G., Jennings, S., Kenny, A., Rijnsdorp, A., and van Kooten, T., 2015. Similar effects of bottom trawling and natural disturbance on composition and function of benthic communities across habitats. Mar Ecol Prog Ser. 2015;541:31–43. Available at https://backend.orbit.dtu.dk/ws/portalfiles/portal/119579329/Post_print.pdf [Accessed on 04.10.2023].