Scientific Cooperation to Support Responsible Fisheries in the Adriatic Sea General Fisheries Commission for the Mediterranean (GFCM) Scientific Advisory Committee (SAC) Subcommittee on Stock Assessment (SCSA) - Rome, 26-30 September 2005 Anchovy (Engraulis encrasicolus, L.) stock assessment in the Adriatic Sea: 1975-2004 N. Cingolani a , A. Santojanni a , E. Arneri a , A. Berlardinelli a , S. Colella a , F. Donato a , G. Giannetti a , G. Sinovcic b , B. Zorica b , B. Marceta c a Istituto di Scienze Marine - Sezione Pesca Marittima, Ancona (Italy) b Institute of Oceanography and Fisheries, Split (Croatia) c Fisheries Research Institute of Slovenia, Ljubljana (Slovenia)
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Scientific Cooperation to SupportResponsible Fisheries in the Adriatic Sea
General Fisheries Commission for the Mediterranean (GFCM)Scientific Advisory Committee (SAC)
Subcommittee on Stock Assessment (SCSA) - Rome, 26-30 September 2005
Anchovy (Engraulis encrasicolus, L.) stock assessment in the Adriatic Sea: 1975-2004
N. Cingolani a, A. Santojanni a, E. Arneri a, A. Berlardinelli a, S. Colella a, F. Donato a, G. Giannetti a, G. Sinovcic b, B. Zorica b, B. Marceta c
a Istituto di Scienze Marine - Sezione Pesca Marittima, Ancona (Italy)b Institute of Oceanography and Fisheries, Split (Croatia)
c Fisheries Research Institute of Slovenia, Ljubljana (Slovenia)
FAO – Fishing area 37: FAO – Fishing area 37:
Mediterranean and Black Sea - GSAMediterranean and Black Sea - GSA
GSA 17GSA 17
Map showing the boundaries of the Adriatic Sea Geographical Sub-Areas (formerly Geographical
Management Units) as originally indicated by the GFCM (solid line) and with the recent revision (dotted line)
The trend of mid-year total (=stock) biomass at sea derived from the VPA performed using data from 1976 to 2004, is compared with the average density (t/nm2) of anchovy, obtainedby acoustic survey in North Adriatic (1987 - 2004; in 2002 and 2003 acoustic survey was not performed)
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Year
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nm
sq
.)
CatchesMid-year stock biomassAnch. density (echo-survey)
Anchovy GSA17: CPUE calculated for the fleet of Porto Garibaldi(mid-water trawlers or volanti), from 1976 to 2004
Anchovy GSA17: empirical relationship between the abundance at seaof spawners in the year n and recruits in the year n+1 (the latter beingreported near the data points), on the basis of VPA estimates
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76 78 80 82 84 86 88 90 92 94 96 98 00 02 04
Year
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Estimated
Threshold (Patterson, 1992)
ConclusionsStock biomass of anchovy dropped at very low level in 1987.After this collapse a slow, but continuous recovery of biomass took place.The present assessment shows a stronger recovery during last two years.Due to high biomass fluctuations of small pelagicsit is recommended to maintain the current level of fishing effort.
