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Small pelagics in the Gulf of Lion Protocol of acoustic survey is the same since 1993 and follows Medias one Pelagic species assessed are : –Anchovy and sardine in first priority –Other one’s if present in the area Total small pelagic species biomass fluctuates a lot between 1993 and 2007 with the highest level in 2005 with more than 472000 tons GFCM - SCSA - Izmir 22-26 September 2008
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Pelmed03 - July
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Pelmed04 - July
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Pelmed05 - July
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Pelmed06 - July
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Pelmed07 - July-August
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Pelmed08 - July
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Représentation en % de la densité acoustique détectée, par couche de 20 m pour les 10 campagnes PELMED
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Stock assessment of small pelagics in the Gulf of Lion Estimated biomass for 2007 –Anchovy : 18500 tons –Sardine : 56300 tons –After a downward trend for anchovy since 2001 peak, relative stabilization from 2005 to 2007 at a low level –After an upward trend of sardina from the 2003 to 2005, return at a mean level in 2006 and 2007
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Pelmed 01 - July
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Inshore anchovy biomass In the gulf of Lion 0 20000 40000 60000 80000 100000 120000 199319941995199619971998199920002001200220032004200520062007 Years Biomass (MT) Biomass Bio - Sd Bio + Sd Offshore anchovy biomass In the gulf of Lion 0 20000 40000 60000 80000 100000 120000 199319941995199619971998199920002001200220032004200520062007 Years Biomass (MT) Biomass Bio - Sd Bio + Sd
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Length structure of anchovy in the gulf of Lion during Pelmed surveys 2004 - 2007
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Pelmed 02 - July
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Pelmed05 - July
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Mid-water sardine school
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Pelmed02 à 05 - Bancs de pleine eau Pelmed02 Pelmed04 Pelmed03 Pelmed05
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Bancs de maquereaux de pleine eau Pelmed04 Pelmed05
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Pelmed06 - July
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Pelmed06 - Anchovy biomass/ESDU
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Pelmed07 - Anchovy biomass/ESDU
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Small sardine (<13cm) : total zone 0 10000 20000 30000 40000 50000 60000 70000 20032004200520062007 years biomass (MT) 6 6.2 6.4 6.6 6.8 7 7.2 7.4 7.6 7.8 8 mean weight index (g) Eval. by ESDU Eval. by zone Mean weight index(g) Big sardine (>=13cm): total zone 0 50000 100000 150000 200000 250000 300000 20032004200520062007 years biomass (MT) 22 23 24 25 26 27 28 mean weight index (g) Eval. by ESDU Eval. by zone Mean weight index(g) 0 10000 20000 30000 40000 50000 60000 20032004200520062007 Years biomass (MT) 15.5 16 16.5 17 17.5 18 18.5 19 19.5 20 mean weight index (g) Eval. by ESDU Eval. by zone Mean weight index(g) Anchovy : total zone Comparative evolution between biomass assessed by ESDU and by homogeneus zones, mean weight index
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Pelmed08 - June July
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Juvalion07 - December
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?
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Length structure for anchovy landed in the gulf of Lion
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Length structure for sardine landed in the gulf of Lion
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Stock assessment of small pelagics in the Gulf of Lion Conclusion –Small pelagic assessment by acoustic methodology seems reliable for anchovy and sardine –Sardine and anchovy stocks show important annual fluctuations. Anchovy stock, more sensitive, has to be follow carefully from biomass and landing indicators –Alternative methods for estimating biomass has to be implemented and compared with currents one ’s ‘
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Small pelagics in the Gulf of Lion SCSA management advice and recommendations –Anchovy As biomass estimation for 2005 - 2007 remain lower than previous years, SCSA recommend to not increase fishing effort and to follow with a great attention the gradual changes in all indicators of stock status –Sardine As biomass estimation for 2006 - 2007 remain lower than 2005 one, SCSA recommend to not increase fishing effort, even if it appears that there could be a strong recruitment in 2008.
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Small pelagics in the Gulf of Lion GSCSA scientific recommandations For anchovy, as GSA07 is closed to GSA06, a survey has been done in 2008 from the south of Ebro to the Gulf of Lion with the aim of assessing anchovy spawning stock in June-July. A second survey could be done for estimate recruitment in November-January in the same area. A strong cooperation between Spain and France to plan these surveys would be encouraged For anchovy and sardine and with the aim of assess shared stocks, re-enforce the cooperation between Spain and France to actualise biological data as well as catches and effort one ’s for the boats of the two nations catching this species in the Gulf of Lion
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