Flemish Cap cod collapsed in early 90’s after facing multiple threats due to climate variability and anthropogenic pressures. This study try to disentangling the effect that these and other extrinsic factors (prey availability, density dependency and maturity) have on cod growth, analysing 35-years of growth chronology reconstructed by using sclerochronology techniques. The quality of the dating was checked with COFECHA software. Moreover, hierarchical mixed-effects models were used to identify drivers of growth. This study shows that cod growth has decreased over the years and it is currently at minimum level of the historic series. Individually, Bottom temperature, CLIME index, Pandalus abundance, Cod abundance, Recruitment, Proportion of matures and Fishing mortalityhas either a linear or curvilinear relationship. The optimum final model indicates that changes in the ecosystem structure are the main responsible of growth variations, being most of these changes directly driven by fishing. However, Flemish Cap is highly vulnerable in the context of climate change as future scenarios predict an increase in temperature and a strong deoxygenation, which may exacerbate cod shrinkage. Understanding the effect of extrinsic factors on cod growth is key to forecast stock productivity and to set limit referent points that guarantee the stock sustainability.
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