Cuartas, Paloma, Gordon, Iain J., Hester, Alison J., Perez-Barberia, F. Javier, and Hulbert, Ian A.R. (2000) The effect of heater fragmentation and mixed grazing on the diet of sheep Ovis aries and red deer Cervus elaphus. Acta Theriologica, 45 (3). pp. 309-320.

PDF (Published Version) - Published Version Restricted to Repository staff only

 

7

1

Abstract

The effects of vegetation fragmentation and mixed grazing (ie mono- or multi-species animal group) on the diet composition of sheep and red deer grazing mosaics of grassland and heather moorland was studied, using faecal cuticle analysis, in two experimental sites in Scotland during the summer of 1992 and 1993. On Site A, the influence of grassland fragmentation on diet composition was estimated for sheep and deer grazing together in plots where the grassland (20% of the area) was artificially distributed as one large, four medium or twelve small patches within a homogeneous moorland matrix (80% of the area). On Site B, differences in diet composition between animals grazing within mono-species (sheep or deer) and multi-species groups (sheep and deer together) were examined for each animal species. In this site all plots used contained a similar natural mosaic pattern of grass and heather (ie similar mixtures of patch sizes, with about 20% grass and 80% heather cover). On Site A, the proportions of grass in the diet of sheep (73%) and deer (27%) were found to be similar across all levels of grass fragmentation. A significant interaction was found between the pattern of fragmentation and the three periods in which the experiment was carried out. On Site B in 1992, sheep had more grass in their diet than did deer (52% vs 46%), and the diets of both sheep and deer responded in the same fashion when the species were grazing in mono- or multi-species groups. The consumption of grass decreased in both species throughout the period studied, Deer showed no change in the proportion of grass in their diet in the presence or absence of sheep in 1992 (deer 48% vs sheep 50%). But on Site B in 1993, the diet of sheep contained a significantly higher proportion of grasses when they were grazing with red deer (52%) than when they were grazing alone (38%). These results suggest that on grassland/heather moorland mosaics sheep may suffer intraspecies competition to a greater extent than do red deer, particularly where grass is in relatively low supply.

Actions (Repository Staff Only)

Item Control Page