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This Working Document summarises the results of applications of the Annual Egg Production Method (Armstrong et al. 2001, Armstrong and Witthames 2012) to estimate spawning stock biomass of cod and plaice in the Irish Sea in 1995, 2000, 2006, 2008 and 2010, and haddock in 2006, 2008 and 2010. This work is conducted jointly between Cefas and AFBI (Belfast). The Marine Institute (Galway) assisted with fecundity estimates in surveys up to 2008.

Poster.-- NAFO/PICES/ICES Symposium on Reproductive and Recruitment Processes of Exploited Marine Fish Stocks, 1-3 Octubre 2007, Lisboa, Estimation of individual egg production is a key step either to understand the relationship between stock and recruitment or to carry out fisheries independent assessment of spawning stock biomass using egg production methods. The work is demanding on human resources and some times requires large quantities of toxic fixative because many fish are highly fecund and their ovaries may weigh over a kilogram. On the other hand, it has recently been shown for cod (Gadus morhua) that image analysis can automate estimation of fecundity determination using the Auto-diametric method. In this paper, we focus on the precision of the Auto-diametric method applied to a range of species with different spawning strategies caught in ripe or spawning condition. A new method using a solid displacement pipette to remove small (