Nephrops on the Aran Grounds (FU17), Demersal otter trawl
- Content last updated
- 20 September 2019
- Nephrops in Division 7.b (Aran Grounds, FU17)
- Stock Status
Nephrops in Division 7b (Aran Grounds, FU17) has been scored low to moderate risk. The stock is in a safe condition because the stock size is just above MSY Btrigger and the harvest rate (F) is below that of maximum sustainable yield (FMSY). However, the stock size is only just above MSY Btrigger and the harvest rate has fluctuated substantially over recent years so this justifies a moderate rather than a low risk score.
Nephrops in Division 7b (Aran Grounds, FU17) has been scored low risk. The stock is assessed annually by ICES. The Total Allowable Catch (TAC) is set for ICES Subarea 7 as a whole, which could lead to increases in fishing effort on individual functional units of Nephrops. However, there are safeguards under the Multi Annual Plan for the management of Western Waters fisheries to avoid overexploitation of individual functional units.
Surveillance of enforceable measures outside of quota management can be considered moderately effective with adequate enforcement and compliance.
Bycatch for this fishery has been scored high risk. This is because the bycatch and discard rates are high at 47% in Nephrops trawls in this fishery due to the small cod end mesh requirements of the target species. There is also a moderate risk to Protected, Endangered and Threatened (PET) species; these are likely to be impacted by the fishery but have high survival rates. However, measures to reduce bycatch and discards in these fisheries have been the subject of much research over the years, resulting in technical measures which improve selectivity, which in turn have been implemented as a statutory requirement. Further measures, such as modified trawl designs, have been implemented on a non-statutory basis.
The habitat impact of this fishery has been scored a very high risk. This is because Nephrops trawlers target specific habitats containing burrowing mud communities. Changes in the biodiversity of these areas have been associated with trawling. There is a process in place under the OSPAR convention and UK Marine Acts to avoid adverse impacts through the designation of Marine Protected Areas of which two are designated for this FU, one with an overlapping area that may be vulnerable to the gear.