Plasma metabolite concentrations of dunlins sampled at the Tagus estuary at different migratory stages (early, mid and late) during spring and autumn migrations.

Data (mean ± confidence intervals of the mean) are predictions from the selected models (see Table 1) where significant covariates were set with the same mean value in all groups. Different letters indicate significant differences between stages within the same migration (see Results). N = 13, 33 and 16 for early, mid and late stages, respectively, in spring migration; N = 16, 19 and 18 (20 for β-hydroxybutyrate and uric acid) for early, mid and late stages, respectively, in autumn migration.