Advice October 2014 Version 2, December-2014

Transcription

1 Advice October 2014 Version 2, December-2014 ECOREGION STOCK Celtic Sea and west of Scotland Undulate ray (Raja undulata) in Divisions VIId, e (English Channel) Advice for 2015 and 2016 ICES advises on the basis of precautionary considerations that there should be no targeted fisheries on this stock. Any possible provision for bycatch to be landed should be part of a management plan, including close monitoring of the stock and fishery. Stock status MSY (FMSY) Precautionary approach (Fpa, Flim) Qualitative evaluation MSY (Btrigger) Precautionary approach (Bpa, Blim) Qualitative evaluation Fishing pressure Decreasing Stock size Stable or increasing The current surveys cover only the fringe of the stock distribution and cannot be considered representative of the stock abundance. However, the slight increases in these surveys indices are considered to reflect range expansion from the core stock area (see supporting information), which might indicate an increasing stock. Fishing mortality is inferred to have decreased as the species is no longer targeted, and landings have ceased. Management plans There is no management plan for this stock, or for any ray or skate stock in the ICES area. ICES Advice 2014, Book 5 1

2 Biology Raja undulata forms a discrete population in the English Channel It is also one of the larger-bodied coastal skates. In view of these biological features, it may be vulnerable to localized overexploitation. Raja undulata is a patchily distributed coastal skate, occurring mostly in the central English Channel from the Normano Breton Gulf (Division VIIe) to the Isle of Wight (Division VIId).This coastal and fragmented distribution does not appear to have changed over the last century. In the English Channel R. undulata also has a wide, but patchy distribution. Length-at-maturity is between 78 cm and 83 cm. The length range is from cm (Stéphan et al., 2014). Throughout the species range neonates, juveniles, and egg-laying females have been observed in estuarine and lagoon habitats. The fisheries Undulate ray is one of the main species of skate captured as bycatch in the central English Channel. This is a coastal species that was traditionally exploited by inshore fishing fleets (trawl, tanglenets, and longline) in areas of high localized abundance. French discards in Divisions VIId,e were estimated at >1700 tonnes in 2013, and at similar levels in Catch distribution Total catch (2013) is unknown. Discarding is known to take place but cannot be quantified. Quality considerations The advice is based on precautionary low catches because of missing or non-representative data. The methods applied to derive quantitative advice for data-limited stocks are expected to evolve as they are further developed and validated. Species-specific landings data before the prohibition on landing are unreliable, since the obligation to report such data was only implemented in 2009 and the prohibition on landing undulate ray was introduced in the same year. Fishery-independent trawl surveys provide the longest time-series of species-specific information, although these surveys do not sample all the size classes and habitats for the various species. Improved survey coverage of the main part of the stock range (Division VIIe) has now been introduced. Scientific basis Stock data category Assessment type Input data Discards and bycatch Indicators Other information Working group (ICES, 2014a). No assessment. Commercial catches. Discarding is known to take place but cannot be quantified. French CGFS in Division VIId and UK BTS in Division VIId. None. Working Group on Elasmobranch Fishes (WGEF). 2 ICES Advice 2014, Book 5

3 Supporting information October 2014 ECOREGION STOCK Celtic Sea and west of Scotland Undulate ray (Raja undulata) in Divisions VIId, e (English Channel) Reference points No reference points have been defined for this stock. Outlook for 2015 and 2016 No analytic assessment can be presented for this stock. Therefore, fishing possibilities cannot be projected. Precautionary approach Based on the precautionary approach, ICES advises that there be no targeted fishery for undulate ray unless information is provided to show that such fisheries are sustainable. Additional considerations Available evidence shows that there may be discrete stocks in the English Channel. In view of the patchy distribution, and following the precautionary approach, ICES recommends that no target fisheries should be permitted unless information is provided to show that such fisheries are sustainable. Although locally abundant, this stock has a patchy distribution and is susceptible to local depletion if fishing mortality is too high. ICES advises against targeted fisheries. Measures to prevent targeting and control bycatch should be implemented as part of an agreed management plan. Proposed management measures must be evaluated and ICES is prepared to be involved in such a management plan evaluation. Discard survival is relatively high for this species in this area. The FAO Code of Conduct for developing fisheries should be followed in developing management strategies for this stock (FAO, 1996). The generic TACs and quotas for skates in the Celtic Seas eco-region does not apply to Raja undulata. The TAC regulation states that, when accidentally caught, this species must not be harmed, must be promptly released, and fishermen are encouraged to use techniques to facilitate the rapid and safe release. This stock was placed on the EU s prohibited species list from 2009 until This was a high level, long-term conservation strategy aimed at very depleted and vulnerable species. ICES did not support the listing of Raja undulata on this designation (ICES, 2010). Information from the fishing industry Scientific studies in collaboration with the fishing industry have confirmed the localised abundance of Raja undulata in the central English Channel, from the Normano-Breton Gulf to the Isle of Wight (Divisions VIId,e). Comparison of the basis of previous assessment and advice The basis for the assessment has not changed from last year and is based on the precautionary approach. Sources Ellis, J. R., McCully, S. R., and Brown, M. J An overview of the biology and status of undulate ray Raja undulata. Journal of Fish Biology, 80: Ellis, J. R., McCully, S. R., Silva, J. F., Catchpole, T. L., Goldsmith, D., Bendall, V., and Burt, G Assessing discard mortality of commercially caught skates (Rajidae) validation of experimental results. Report to Defra, xi pp. FAO Precautionary approach to capture fisheries and species introductions. Elaborated by the Technical Consultation on the Precautionary Approach to Capture Fisheries (Including Species Introductions). Lysekil, Sweden, 6 13 June FAO Technical Guidelines for Responsible Fisheries, No. 2. Rome, FAO Section , pp ICES Advice 2014, Book 5 3

4 ICES EC request on Raja undulata. In Report of ICES Advisory Committee, ICES Advice 2010, Book 9, Section ICES. 2014a. Advice basis. In Report of the ICES Advisory Committee, ICES Advice 2014, Book 1, Section 1.2. ICES Report of the Working Group on Elasmobranch Fishes (WGEF), June 2014, Lisbon, Portugal. ICES CM 2014/ACOM: pp. Stéphan E., Hennache, C., Delamare, A., Leblanc, N., Legrand, V., Morel, G., Meheust, E., and Jung, J. L Length at maturity, conversion factors, movement patterns and population genetic structure of undulate ray (Raja undulata) along the French Atlantic and English Channel coasts: preliminary results. Working Document presented at the Working Group on Elasmobranch Fishes (WGEF) meeting, June, Figure Raja undulata in Divisions VIId and VIIe. Mean cpue of Divisions IVc VIId, UK Beam-trawl survey Q3 abundance index. Figure Raja undulata in the English Channel (Divisions VIId,e). Biomass index (cpue standardized to the mean of the whole time-series) in Division VIId, from the French bottom otter trawl survey in Division VIId (CGFS). 4 ICES Advice 2014, Book 5

5 Table Raja undulata in Divisions VIId, e (English Channel). ICES advice and landings. Year ICES advice Predicted catch corresp. to advice Discards ICES Species-specific landings: minimum estimate based on reported landings 2009 No targeted fishery - na na 2010 No new advice, same as 2009 na na 2011 No targeted fishery - >c No new advice, same as 2011 >c No targeted fishery, minimize bycatch - > No targeted fishery, minimize bycatch No targeted fisheries. Any possible provision for bycatch to be landed should be part of a management plan No new advice, same as Weights in tonnes. 1 Version 2, text amended to be in line with the upfront Advice sentence. ICES Advice 2014, Book 5 5