Grazing preferences of mountain hares on heather moorland and hill pastures.
Grazing preferences of mountain hares in relation to the area available of each of 7 main classes of moorland and vegetation in NE Scotland were studied by means of dung plots in 1984-85. On heather [Calluna vulgaris] moorland adjacent to resown hill pastures, mountain hares preferred the youngest class of heather (pioneer) followed by successive age-classes of early-building and late-building. If pioneer heather contained >20% grass, it was less preferred than early-building heather. Wild grass was preferred to all types of heather except pioneer, but resown hill pastures ranked 5th in use among the 7 categories of vegetation. Preferences between the main classes of vegetation were consistent over 2 years. Within the main classes of vegetation (5 of heather, 2 of grass), there were consistent differences between sites. These were associated with the proportion of grass among pioneer heather, preferred sites having >20% heather cover and less grass than the other sites. Preferred sites on early-building heather resembled pioneer heather more closely than did less preferred sites. Selection against height of building heather was the likeliest cause of preferences, and probably a contributory cause in old heather. Old heather, covering 37% of the study area, was used more if it contained open spaces big enough to contain a grazing hare. On hill pastures, grazing by mountain hares declined sharply when sheep were introduced; number of sheep and hares were negatively correlated. Hill sheep preferred the same types of moorland vegetation as mountain hares. There was no obvious competition between hares and rabbits, and grazing by red deer was negligible.