Figures:
Figure 1: Size-corrected Δ13C and Δ15N of muscle and liver tissue (i.e. residuals of regressions of TDFs on fish length) of different weight classes in perch. Weight classes with the same letter are not significantly different (Tukey´s pairwise comparisons). Boxplots depict median, 25th and 75th percentile, and whiskers extend to maximum and minimum values, except for outliers (>1.5 times box height, represented by dots).