Pairwise FST values plotted against A distance between sampling sites, or B number of river barriers between sampling sites, paneled by river system. * shows a significant (P < 0.05) result from the MRM models. Slopes derived from a linear regression to aid in visualizing the MRM model results, coloured data points show raw values. Note, the Morava river was not included in the MRM analyses because only two sites were sampled.