English: "a Mean fish length has changed in a nonlinear pattern, as demonstrated by the nonlinear year effect from GAMs on mean population length with fixed effects of region and population. b Mean freshwater age (in years) has generally declined, except for chum salmon, which leave freshwater shortly after emergence. c Mean saltwater age (in years) has also generally declined, except in chum salmon, which increased in saltwater age until around 1990, then decreased. Plots are conditioned on reference populations with the longest time series for each species, but the pattern plotted is the common pattern through time calculated for all populations. Gray areas represent 95% confidence intervals for the nonlinear year effect. d Male salmon in spawning coloration. Sample sizes are presented in Supplementary Data 5."