Sex, seasonal and spatial differences in the diet of Cantabrian chamois Rupicapra pyrenaica parva

Abstract

The relationships between availability and quality of food, diet composition and habitat use of female and male chamois herds Rupicapra pyrenaica parva (Cabrera, 1911), were investigated in the Cantabrian Mountains (Spain). The two vegetation types studied were grass-forb and shrub. Grass-forb contained higher crude protein and lower fibre than shrub throughout year (crude protein: 17.2% vs 8.6%, p = 0.018; acid detergent fibre: 27.0% vs 35.8%, p = 0.018). The diet of female and male herds showed more grass-forb than shrub (p = 0.012), however, a discrepancy between site selection and bite selection was found. Generally male herds were found in shrub areas although they mainly chose grass-forb in their diet. Female herds had a higher percentage of grass-forb in the diet than male herds throughout the year (81.6% vs 65.6%). Diet composition pattern was similar in both sexes, with a peak of grass-forb in spring and autumn, and a minimum in summer. Both sexes selected grass-forb throughout the year, but its use was increased when its quality was high, inde-pendently of quantity available. Females showed higher grazing activity than males throughout year (53% vs 37%, p < 0.0001). Male herds showed less grazing activity during the rut (October-November) in comparison with the rest of the year (25% vs 43%, p < 0.0001). Some hypotheses to explain the segregation of the herds of both sexes are presented and discussed.