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MEDITERRANEAN SWORDFISH. SCI-020. Background. Unique genetic stock Some mixing with the N. Atlantic one Different biological characteristics than the Atlantic stocks Last assessment few weeks ago. Fishery. Catches around 12000-16000 t in the last decade.
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MEDITERRANEAN SWORDFISH SCI-020
Background • Unique genetic stock • Some mixing with the N. Atlantic one • Different biological characteristics than the Atlantic stocks • Last assessment few weeks ago.
Fishery • Catches around 12000-16000 t in the last decade. • 14000 t in 2005. Incomplete information for 2006. • Gears: Longlines & Gillnets
Catch composition • Large catches of juveniles (50-70%) SWO Figure 4 Proportion of catch numbers at age by year.
Stock assessment } • Two assessment types • Production modelling (long data series) • Age based VPAs (short data series) Stock decline
State of the stocks Current stock level about 13% lower than optimum Production modeling Current F about 25% higher than optimum 40% reduction in spawning stock level but modest changes in the last decade VPA Stable recruitment over the past 20 years. Current spawning stock level half than optimum Y/R Current F double than optimum
Current (2005) stock status VPA median Prod. Mod. median
Time trends VPA Production modeling
Projections VPA Production modeling
Assessment conclusions • The stock is below the level which can support MSY • Current fishing mortality exceeds FMSY. • The degree to which biomass is below BMSY and F is above FMSY differs between assessment models. • Fishing pressure needs to be reduced to move the stock towards to biomass levels which could support MSY and away from levels which could result in non-negligible risks of rapid stock decline; although such worrying signals have not been seen so far in the fisheries.
Exploitation scenarios Fishery closures during recruitment
Management recommendations • Adoption of a management plan with the goal of rebuilding the stock to levels that are consistent with the ICCAT Convention objective. • Technical measures, such as fishery closures and gear modifications, as well as capacity reductions should be considered in the frames of a management plan