Vegetation community selection by ungulates on the Isle of Rhum. II. Vegetation community selection.
Abstract
The seasonal pattern of vegetation community use and selection by free-ranging cattle, red deer, goats and ponies on the Isle of Rhum, Scotland in 1982-83 is described. Cattle, red deer and ponies preferentially selected grassland communities, whereas goats preferred heath communities. All species showed marked seasonality in their use of the available vegetation communities. The majority of the grazing species selected the mesotrophic Agrostis - Festuca communities in spring and summer. During the autumn and winter, the cattle selected oligotrophic grasslands, Molinia fen and Schoenus fen, whereas, the red deer and ponies remained on the mesotrophic communities. Female goats selected the mesotrophic communities, whereas the males selected the oligotrophic communities. All species showed an increase in their breadth of vegetation community use in spring and autumn and concentrated their feeding activity on few communities during the winter and summer. The feeding ecology of the red deer stags appeared to be affected by the cull during the summer months, as they used the mesotrophic communities less than did the hinds and less than the stags in an unculled area of the island. The female red deer made more use of the higher quality mesotrophic communities in winter than the stags.