[Ital J Anim Sci vol.11:e9, 2012] [page 47] Wild red deer (Cervus ela-phus L.) grazing may seri-ously reduce forage produc-tion in mountain meadows

This study aimed at estimating the impact of red deer grazing on the productivity of mead-ows located in Pian Cansiglio, north-eastern Italian Pre-Alps. These meadows (185 ha; aver-age elevation 1000 m asl are managed for hay/silage production (1-2 cuts per season) and are included in a protected area that hosts a high density of deer (around 30 heads/100 ha). In 2008 and 2010, dry matter (DM) pro-duction and loss due to deer grazing were esti-mated with exclusion cages (1 m2; 48 exclu-sion cages in 2008 and 52 in 2010). Night counts with spotlights were conducted to index deer use of meadows plots. DM production inside the cages was fairly good for the area (first-second cut: 4963-2297 kg DM/ha in 2008, and 4145-2475 kg DM/ha in 2010). DM produc-tion outside the cages was significantly lower (first-second cut in 2008: 4199-1378 kg DM/ha, and in 2010: 3376-2052 Kg DM/ha). Therefore, the magnitude of losses was of 15-20 % at the first and 25-40 % at the second cut. DM losses in the different meadow plots were positively correlated with index of deer use, which in some plots was as high as 7-8 heads/ha. Deer grazing reduced also crude protein (CP) con-tent of forage (15.6±4.4 % DM inside exclusion cages and 13.8±3.5 % DM outside), with losses being greater where CP content was higher. This study demonstrates that high densities of grazing deer may seriously impact on forage production and quality