Fig. 3

Calculated detection radii during the main eel migration season in autumn of the estuarine receivers (Array 7); 80%-detection range = 98 m; 50%-detection range = 197 m. The blue rounded arrows indicate the current direction and the colouration symbolize different maximum ebb current velocities (red—fast (~ 1.4 m/s), yellow—medium (~ 1 m/s), green—medium slow (~ 0.7 m/s), blue—slow (< 0.5 m/s) originating from Herrling et al. [26]. Resolution of original figure upscaled using an AI-tool (aiseesoft.com)