Results of Convergent Cross Mapping applied to the global and the local abundance indices of the Eastern Atlantic yellowfin tuna. The red and black lines represent the effect of Global on Local and conversely. Thin colour lines show mean ± SD from bootstrapping. The figure presents predictability (rho) as a function of library size (L). The p value is for the significance of each causation direction. Causal forcing is indicated when rho is significantly greater than zero for large library length L and that rho increases significantly with increasing L.