1. Ministry of Food, Agriculture and Fisheries Danish Institute for Fisheries Research ICES Symposium on management strategies - SFMS-25 FLEET-BASED SHORT-TERM ADVICE IN MIXED FISHERIES – THE F 3 APPROACH Clara Ulrich, B.S. Andersen, H. Hovgård, P. Sparre (DIFRES), A. Murta (IPIMAR), D. Garcia (AZTI), J. Castro (IEO)

2. Ministry of Food, Agriculture and Fisheries Danish Institute for Fisheries Research Background – ICES WKMIXMAN Needs to find a method for mixed-fisheries advice to replace MTAC. Issues raised: –Mismatch between the allocation of effort to individual fleets and the relative stability within European fisheries –Constant catch compositions of fleets in the forecast –High sensitivity of results to the inputs, both in terms of fleet/fishery catch data and policy weightings –No respect of management objectives for all stocks Requirements for alternative methods (MoU) : –Simple model –Based on currently available and accessible data –Account for changes in fishing practices

3. Ministry of Food, Agriculture and Fisheries Danish Institute for Fisheries Research Background - TEMAS model and TECTAC project Modelling management strategies in multifleet multispecies fisheries Year Y With data Y-1 With effect Y+1 Y+1 ?

4. Ministry of Food, Agriculture and Fisheries Danish Institute for Fisheries Research F 3 – Fleet and Fisheries Forecast Cornerstone : catch AND effort data Fleet AND métiers (fisheries) Fleet (vessels)Métier (trips) Species (catches) EFFORT CATCHABILITY Data : catch and effort database : each vessel to a fleet, each trip to a fishery F and biomass estimates by stock Forecast by stock

5. Ministry of Food, Agriculture and Fisheries Danish Institute for Fisheries Research F 3 - Main assumptions F=qE A vessel in a fleet can engage in several metiers during the year The catchability of a metier can be measured and assumed known – but not the catchability of a vessel (fleet) The overall catchability of a vessel (fleet) is forecasted as weighted mean of catchability by metier and time spent in each metier The relative stability by country also applies at the fleet level (especially in right-based regimes) The fleet will balance its total effort according to its quota shares, and overquota catches might occur Options : MAXEFFORT : fish until last quota exhausted / MINEFFORT : stop fishing when first quota exhausted

6. Ministry of Food, Agriculture and Fisheries Danish Institute for Fisheries Research F 3 - Overview Assessment F(St)Effort (Fl,Mt)Catches (Fl,Mt,St) PartialF(Fl,Mt,St) Q(Fl,Mt,St) ForecastQ(Fl,Mt,St) EffortDistr(Fl,Mt) ForecastEffortDistr(Fl,Mt) ForecastQ(Fl,St) Forecast F(St) Rel. Stab (Fl,St) ForecastF(Fl,St) Forecast Effort (Fl,St) Management rule Forecast Effort (Fl) Forecast Catches (Fl,Mt,St)Forecast OverQuota (Fl, St) (MAX,MIN,WEIGHTED MEAN Effort bound…) Forecast B(St) Forecast TAC(St) assumptio n Forecast F (Fl,Mt,St) Forecast landings (Fl, St)

7. Ministry of Food, Agriculture and Fisheries Danish Institute for Fisheries Research F 3 – WGHMM06 – Southern Stocks – Trial runs 8 Stocks –MEGRIM (*2), HAKE, ANGLERFISH, NEPHROPS (*4) 6 Fleets and 13 Fisheries: –PT artisanal : 3 fisheries (target species) –PT trawl : 2 fisheries (target species) –SP artisanal : 2 fisheries (areas) –SP gillnet : 3 fisheries (gear*target species) –SP longline : 1 fishery –SP trawl : 2 fisheries (areas) 3 scenarios –2005 ACFM proposal –2006 TAC –Southern Hake recovery plan (reduce F by 10%)

8. Ministry of Food, Agriculture and Fisheries Danish Institute for Fisheries Research Southern Stocks – Sc1 ACFM proposal (trial runs) LDBFsq HKEZero catch MEGFsq MNZZero catch NEP 25Zero catch NEP 26-27Zero catch NEP 28-29 f80 t NEP 28-29 m120 t MAX EFFORT MIN EFFORT (bounded) NOT COMPATIBLE!!

9. Ministry of Food, Agriculture and Fisheries Danish Institute for Fisheries Research Southern Stocks – Sc2 TAC 2006 (trial runs) LDB1129 HKE6661 MEG139 MNZ1955 NEP 25146 NEP 26-2729 NEP 28-29 f116 NEP 28-29 m174 MAX EFFORT MIN EFFORT Effort by fleet, MINEFF vs MAXEFF

10. Ministry of Food, Agriculture and Fisheries Danish Institute for Fisheries Research Southern Stocks – Sc2 TAC 2006 (trial runs) MAX EFFORTMIN EFFORT F landings F total

11. Ministry of Food, Agriculture and Fisheries Danish Institute for Fisheries Research Southern Stocks – Sc3 Hake recovery plan (trial runs) MAX EFFORTMIN EFFORT

12. Ministry of Food, Agriculture and Fisheries Danish Institute for Fisheries Research F 3 –Southern Stocks - conclusions Single-species TAC are not efficient tools for reducing F. They induce unaccounted fishing mortality and bias in assessment Single species management plans cannot be achieved without considering mixed-fisheries interactions It would be possible to formulate mixed-species TAC by fleet including some management objectives and priorities Mixed-fisheries management should ideally be at the fleet/vessel level, rather than at the fishery or stock level, to account for changes in activity No good input and assessment data – results are only used for demonstration

13. Ministry of Food, Agriculture and Fisheries Danish Institute for Fisheries Research F 3 - Discussion A process model; mathematically simple, transparent.  Assume relationship between F and E, needs reliable single species forecast Uses landings and effort (better use of existing data than MTAC)  Good data requirements. Requires preliminary work to define exhaustive fleets and fisheries Compatible with relative stability  Assumption on fixed quota share allocation between fleets Based on manageable units, links with economics and with effort regulation  Sensitivity to aggregation level and fleet-fisheries definitions? No assumptions on fixed catch composition (only fixed catchability by metier)  Catchability varies between vessels, time period etc. Measured on landings! Can account for finer analyses  More complexity would make it less tractable

14. Ministry of Food, Agriculture and Fisheries Danish Institute for Fisheries Research F3 – Future developments Needs additional testing and sensitivity analysis Link with economics – relation with the EIAA model used for economic advice How to deal with age-based approach? Improvement of the relationships between effort and mortality : better effort definitions and catchability estimates (cf TECTAC, CAFÉ…) Inclusion of flexibility in effort allocation by fishery – behavioral analysis of metier choice (cf Andersen et al., SFMS 32) Is that of use for management? Can we implement mixed species TACs for the individual fleets?