Tuesday, 4 December 2018

Celtic Seas ecoregion – Fisheries overview, including mixed-fisheries considerations.

Executive summary

The commercial fisheries in the Celtic Sea target a large number of stocks. The pelagic fisheries, which account for the largest catches (by weight) in the region are the mid-water trawl fisheries for blue whiting, mackerel, horse mackerel, herring, boarfish, and sprat. The largest demersal fishery targets hake along the shelf edge using gillnets and longlines. There are also large mixed bottom-trawl fisheries targeting benthic species, Nephrops, and gadoids. The species composition of these mixed fisheries tend to vary, depending on the area and the countries involved in the fishery.

The relationship of biomass status or the fishing mortality to reference points is not known for more than 50% of the 106 stocks that are assessed in the ecoregion.. Though only 29% of the stocks are fished below FMSY, these stocks account for nearly 12% of the total landings. There has been a trend of declining fishing mortality since the mid-1990s for the benthic and demersal stocks with known status, and the average F/FMSY ratio is now approaching 1 for the first time. The trend for stock size in assessed benthic and demersal stocks has been increasing over the same period. The trend in average F/FMSY ratio for pelagic assessed stocks has been increasing in the last few years although the average stock size indicator remains above MSY trigger.

The technical interactions in demersal mixed fisheries are described for three areas within the ecoregion. Nephrops account for the highest landings in the Irish Sea; they are mainly taken in trawl fisheries where they account for more than 90% of the total landings. In the Celtic Sea and west of Ireland hake account for the majority of the landings; they are mainly taken in longline and gillnet fisheries which are also dominated by hake. In the west of Scotland Nephrops again account for the highest landings; they are mainly taken using otter trawls, but also in pots. ICES carries out mixed-fisheries forecasts for cod, haddock, and whiting caught in mixed demersal fisheries in the Celtic Sea. These forecasts take account of the technical interactions not included in the single-stock forecasts. For 2019, no catch of haddock or whiting is consistent with the cod single