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Small pelagics in the Gulf of Lion

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

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Small pelagics in the Gulf of Lion

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  1. 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

  2. Pelmed03 - July

  3. Pelmed04 - July

  4. Pelmed05 - July

  5. Pelmed06 - July

  6. Pelmed07 - July-August

  7. Pelmed08 - July

  8. 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

  9. Inshore anchovy biomass In the gulf of Lion 120000 Biomass 100000 Bio - Sd Bio + Sd 80000 Biomass (MT) 60000 40000 20000 0 1996 1997 2002 2003 1993 1994 1995 1998 1999 2000 2001 2004 2005 2006 2007 Years Offshore anchovy biomass In the gulf of Lion 120000 Biomass 100000 Bio - Sd 80000 Bio + Sd Biomass (MT) 60000 40000 20000 0 1993 1994 1997 1998 2002 2003 2004 2007 1995 1996 1999 2000 2001 2005 2006 Years

  10. Length structure of anchovy in the gulf of Lion during Pelmed surveys 2004 - 2007

  11. Pelmed05 - July

  12. Pelmed06 - Anchovy biomass/ESDU

  13. Pelmed07 - Anchovy biomass/ESDU

  14. Small sardine (<13cm) : total zone Eval. by ESDU 70000 8 Eval. by zone Comparative evolution between biomass assessed by ESDU and by homogeneus zones, mean weight index Mean weight index(g) 7.8 60000 7.6 50000 7.4 7.2 40000 biomass (MT) mean weight index (g) 7 30000 6.8 6.6 20000 6.4 10000 6.2 0 6 2003 2004 2005 2006 2007 years Anchovy : total zone Big sardine (>=13cm): total zone Eval. by ESDU Eval. by ESDU Eval. by zone 60000 20 Eval. by zone Mean weight index(g) 300000 28 Mean weight index(g) 19.5 50000 250000 27 19 40000 18.5 200000 26 18 biomass (MT) biomass (MT) mean weight index (g) mean weight index (g) 150000 25 30000 17.5 100000 24 20000 17 16.5 50000 23 10000 16 0 22 0 15.5 2003 2004 2005 2006 2007 2003 2004 2005 2006 2007 years Years

  15. Pelmed08 - June July

  16. Juvalion07 - December

  17. ?

  18. Length structure for anchovy landed in the gulf of Lion

  19. Length structure for sardine landed in the gulf of Lion

  20. 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 ‘ 

  21. 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.

  22. 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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