Number and diversity (±SD) of ND2 sequences used in this study.

<p>Diversity indices were not calculated for populations with very small sample sizes (Biebrza and Krasnodar), nor for wintering sites (Djoud and Lake Chad). ns – non-significant; *** – P<0.001; ** – P<0.01; * – P<0.05.</p><p>n – sample size.</p><p>S – number of segregating sites.</p><p>H – number of haplotypes.</p><p>Hd – haplotype diversity.</p><p>K – average number of pairwise differences.</p><p><b>π</b> – nucleotide diversity.</p><p>R2– Ramos-Onsins & Rozas (2002) test.</p><p>τ – time of population expansion (τ = 2 µT).