Fig. 6

Relationship between salinity of the estimated position and days spent at sea for the eight kelts during the first 15 days at sea, modelled with a mixed effects model. Shaded areas represent 95% confidence intervals of the model, while points represent actual observations. Dotted lines represent trend lines for each of the eight kelts. Residuals for the model are presented in Additional file 1: Fig. S1. Salinity on the estimated position after 15 days at sea was lower than at sea entry for all eight kelts