Figure 2
From: What seeds tell us about birds: a multi-year analysis of acorn woodpecker foraging movements
Frequency plots of weighted Z-scores. Distribution of weighted nested Mann–Whitney-Wilcoxson rank order scores permutated within granary for Q. lobata (A) and Q. agrifolia (B) and the actual average value indicated by dashed line and its associated P-value. P-values test whether the difference of foraging movement in bad years minus distance moved in good years is significantly greater than zero. (See text and Additional file 1 for detail).