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Fishery and Sea ResourcesFigure 6: % of Variations of Spawning Fraction and Biomass between new and old evaluationmethods.of the present paper that is more devotedto analyze the effect of spawning fractioncomputation method on the total biomassvariability. Generally when applied in newareas or to new species DEPM estimateshave to be re-evaluated after several yearsperiod application, as it is also suggestedby the rather long time lag existing betweenthe DEPM worldwide applicationsand their publication [14].Using the system applied in the Ocean, theresorption rate of postovulatory folliclesis overestimated. Consequently, the dailyspawning fraction was underestimated,thus overestimating the stock biomass.References[1] IREPA. Osservatorio economico sulle strutture produttive della pesca marittima inItalia 2006. XV Rapporto. 2007.[2] A.R. Wallace and K. Selman. Cellular and dynamic aspects of oocyte growth inteleosts. American Zoologist, 21:325–343, 1981.[3] J.R. Hunter and S.R. Goldberg. Spawning incidence and batch fecundity in northernanchovy (Engraulis mordax). Fishery Bulletin US, 78:811–816, 1980.[4] K. Parker. A direct method for estimating northern anchovy, Engraulis mordax,spawning biomass. Fishery Bulletin US, 78:541–544, 1980.[5] J.R. Hunter and B.J. Macewicz. Measurement of spawning frequency in multiplespawning fishes. in R. Lasker, editor. An egg production method for estimatingspawning biomass of pelagic fish: application to the northern anchovy, Engraulismordax. U.S. Dept Of Commerce NOAA Technical Report, 36:41–69, 1985.2122