Seasonal changes of body mass and fat reserves in chamois. a Seasonal changes of the eviscerated body mass of males (blue) and females (red), b of relative visceral fat mass, and c of relative kidney fat mass. Among males, we discriminated between reproductively active males older than four years  (circles, solid lines), and younger animals (diamonds, dashed line). Plotted are monthly means ± standard errors with sample sizes of one indicated by symbols with white dots. Sinoidal curves are the seasonal mass changes predicted from cosinor analysis (all amplitudes differ from 0 with P < 0.001). Horizontal thick lines indicate the 95% confidence interval of the estimated date of the annual nadir (a), or corresponding peaks (b,c), respectively.