Figure 1.

(a) Adult green turtles migrate from coastal South America to nest at AI (ocean current velocity indicated by scale and arrows, averaged over January 2014). (b) IBM simulations. Simulated paths over 50 days following an individual's displacement from AI (star), where the individual acts as a drifter, a weak or a strong navigator: only the latter reaches AI within the simulation time; the displayed ocean currents are averaged over the 50 day period. (c,d) Population distribution snapshot of the (c) IBM and (d) continuous model (75 days post-release): simulation details in figure 7. (Online version in colour.)