Variations saisonnières du régime alimentaire du chevreuil ( Capreolus capreolus) en Haute Belgique

In Belgium, information related to the deer food are quite uncommon and, as far as the roe deer is concerned, restricted to the hunting season (autumn). Our study was conducted in two areas of Southern Belgium. The first, in Hotton (50°15 N, 5°27 E) is a mixed oak-beech forest with an important cover of brambles. Faeces samples were collected monthly from october 1987 to september 1988. The second area, inside the Nature reserve of "Les Hautes Fagnes" (50°30 N, 6°06 E ; 600 m) is an old peat-bog (Eriophorum vaginatum, Molinia coerulea, Vaccinium myrtillus and V. uliginosum) surrounded by spruce plantations. Sampling took place there only in April and in June 1989. Faeces were boiled and filtered before digestion in the Scharrer-Kurschner mixture for 30 min. Then samples were sieved under water and a small amount taken and mounted on a slide for microscopic observation. More than 13000 small vegetal pieces were identified to the species by comparison between the observed epidermal features and a reference collection of plant epidermis. Woody plants are the main food of the Roe deer in both areas : in the Hautes Fagnes, heather (Calluna vulgaris) and bilberry (Vaccinium) are the main food items whereas in Hotton, brambles are the most important part of the diet in each season. In Hotton, we found that the diet was much more diversified during the green season than in the winter. The winter diet comprises mainly brambles but also heather and Vaccinium myrtillus in low quantities. Spruce needles are present only at the end of the winter. In the spring, grasses were taken but their contribution to the food of the deer was never important. During the summer, the Roe deer ate more tree leaves (Quercus robur and Sorbus aucuparia). In the Hautes Fagnes, grasses were important only in the spring diet and tree leaves (Sorbus) in the summer. Some tree species were very common in both study areas (beech and spruce saplings) but nearly not eaten. The Roe deer can thus be considered as a selective feeder preferring high quality foods (spring grasses or young leaves) to bulky one (old grasses or hard leaves).