SWWRAC (problemas de datos, afeccion de estos a la evaluacion y consejo) Anglerfish (L. piscatorius & L.budegassa) in Subarea VII & Divisions

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1 1 SWWRAC (problemas de datos, afeccion de estos a la evaluacion y consejo) Anglerfish (L. piscatorius & L.budegassa) in Subarea VII & Divisions VIIIa,b,d,e

2 OVERVIEW 2 Megrim (Divisions VIIb-k and VIIIabd): Marina Santurtun 1. review of current stock status and assessment method and quality 2. review of available data and data quality 3. consideration of new input data 4. stakeholder input 1. Presentacion de los fallos o faltas de los que adolece la evaluacion 2. Como afecta esta falta de datos a la evaluacion y gestión. 3. Identificacion de las acciones necesarias para la mejora de la evaluacion. Plan de Accion. 4. Conclusiones

3 2. Review of available data and data quality 3 Issue Problem/Aim Work needed / Biological Parameters Split of the landings between both species of anglerfish not known for some countries and suspect of not being correctly done some years due to differences between species propor6on among different countries fishing the same grounds. possible direction of solution Have the historical detailed informa6on on methods used by each country. Historically apply the split between species from the best iden6fied method/country/ fleet (i.e. the propor6ons in landings of countries spli?ng the species due to market reasons ). Data needed to be able to do this: are these available / where should these come from? Available directly from historic data or from Member States External expertise needed at benchmark type of expertise / proposed names No need Sex ra9o and maturity of anglerfish only from an European project done in Compila6on of the data collected under DCF and analysis for new sex- ra6o and maturity parameters (COST) Raw data from DCF, NO

4 2. Main issues: Review of available data and data4 quality) Issue Problem/Aim Work needed / Discards Enforcement of laws about minimum landing weight (0.5 kg) changed totally the reten9on ogive and the landings length distribu9on. possible direction of solution Try to reconstruct the length distribu6on of specimens bellow 0.5 kg in the catch or remove the historical data of fish below 0.5 kg from the catch matrix Data needed to be able to do this: are these available / where should these come from? Discard es6mates from all the involved countries External expertise needed at benchmark type of expertise / proposed names No (- RAC incolvement: Basically, I think that RACs can not help much as data should be available at the Fisheries Institutes. It will be maybe good to remember the importance of a good (number of samples and sample size). This is, maybe RAC member could facilitate sampling on board to get discard data which are really important for this stock) Issue Problem/Aim Work needed / Tuning series No standardized commercial tuning data is available possible direction of solution Standardiza6on of commercial tuning data by lengths Data needed to be able to do this: are these available / where should these come from? Raw data from logbooks and the length distribu6ons for that fleet. Data should be available from member states External expertise needed at benchmark type of expertise / proposed names No needed (-RAC involvement. Maybe qualitative information, as for example, technological creeping can be given by Industry.)

5 2. Review of available data and data quality 5 Issue Problem/Aim Work needed / Biological Parameters Growth paiern unknown or poorly known possible direction of solution Research on anglerfishes growth pasern. Could come from tag/recapture experiments, analysis of length distribu6ons from surveys. Data needed to be able to do this: are these available / where should these come from? Workshop to be conducted by ICES in Results are not likely to be applicable to a benchmark in 2012 due to 6me constraints. External expertise needed at benchmark type of expertise / proposed names No Assessment model It depends on data available. If all the data with the needed length distribu6ons is available a length structured model could be used. If only landings data and some tuning series are available a produc6on model could be used. All the above plus exploratory analysis from stock coordinators NO

6 2. Review of available data and data quality 6 Before benchmark Country Improvement SPAIN FRANCE UK IRELAND Revision of landed lengths by metiers for possibility of using them in models no structured in ages Revision of landed lengths by metiers for possibility of using them in models no structured in ages Revision of landed lengths by metiers for possibility of using them in models no structured in ages Revision of landed lengths by metiers for possibility of using them in models no structured in ages BELGIUM

7 3. Review of models available 7 The model 1 (L.piscatorius & L.budegassa): A Schaeffer type model (ASPIC, Prager, 1994): Landings from 1984 to 2010; for the single species and both species combined. CPUEs from the Vigo fleet in two series: and sue to changes in fishing power improving fleet efficiency. CPUEs from the French benthic fleet in the Celtic Sea (FR-FU04) from 1986 to 2010 (2008?); Biomass index from the French EVHOE survey from 1997 to 2010.

8 3. Review of models available 8 Resultados (L.piscatorius): The strong pattern in the retrospective analysis due to lack of contrast of the data: Absence of a response from the biomass to either an increase or a decrease in catch. Parameters cannot be estimated precisely. Resultados (L.budegassa): As the surplus production model was unable to converge using a number of different input options, there are no results available. Conclusion In view of the instability of the model, it was decided that it could not be used as a basis for management advice.

9 3. Review of models available 9 The model 2 (L.budegassa): Length based stock synthesis model A stock synthesis model (NOA Fisheries Toolbox, 2011) was explored using the fol-lowing datasets: Landings from 1984 to 2010 for L. budegassa. Biomass index from the French EVHOE survey (EVHOE-WIBTS- Q4) from 1997 to 2010.

10 3. Review of models available 10 Resultados (L.budegassa): model 2 In view of the instability of the short time-series of landings, lack of commercial cpue index and biological information, it was decided that the stock synthesis could not be used as a basis for management advice at this time. It was recommended to explore and develop the stock synthesis model.

11 11 Conclusions: No basis for changing the current trends based assessment. CATEGORISATION (WKFRAME, WKLIFE) Cat. 3,: stocks for which survey-based assessments indicate trends: This category includes stocks for which survey indices (or other indicators of stock size such as reliable fishery-dependant indices; e.g. lpue, cpue, and mean length in the catch) are available that provide reliable indications of trends in stock metrics such as mortality, recruitment, and biomass. Survey Indices (EVHOE) used for advice.

12 12 La falta de datos en la evaluacion/gestion: Anglerfish (L.piscatorius & L.budegassa) Divisions VIIb k and VIIIa,b,d Consejo para 2013, Data Limited Stocks (Cat.3): Captura < t * En general, las tendencias del stock son estables, aumentando durante 2000s, disminuyendo en años recientes * Descartes de peces pequeños (< 0.5 kg) han aumentado en los ultimos años. Pero no hay estimas de descartes fiables.

13 13 From ICES presentation to NWWRAC: Anglerfish (L.piscatorius & L.budegassa) Divisions VIIb k and VIIIa,b,d Descargas de t (descartes son desconocidos) Descargas españolas no están disponibles para el 2011 Se usa el indice de biomasa de una campaña como indicador del stock: * L. piscatorius: Megrim (Divisions VIIb-k and VIIIabd): (Promedio de los ultimos 2 años) es 14% más Marina bajo que Santurtun (promedio de los 3 años anteriores) 1. review of current stock status and 14% disminucion sobre las descargas assessment method recientes and quality (promedio ): t 2. review of available data and data quality * L. budegassa: 3. consideration of new input data (Promedio de los ultimos 2 años) es 20% 4. más stakeholder bajo que input (promedio de los 3 años anteriores) 20% disminucion sobre las descargas recientes (promedio ): t 1. Ventana de incertidumbre: 14% disminucion para L.pisc y 20% disminucion para L.bude 2. Margen de precaucion: no se aplica, ya que hay una disminucion estable del esfuerzo en las principales pesquerias. Result: t

14 OVERVIEW 14 In subgroups: Megrim (Divisions VIIb-k and VIIIabd): Marina Santurtun 1. review of current stock status and assessment method and quality 2. review of available data and data quality 3. consideration of new input data 4. stakeholder input - Identification of actions needed in order to improve the stock assessment. - Action plan: responsibilities for actions. - conclusions on discussion

15 15

16 Surveys 16

17 Effort Commercial Fleets 17

18 CPUEs Commercial Fleets 18

19 Suevesy grouped by ages 19

20 Commercial Fleets pooled by ages 20