CAPERCAILLIE HABITAT, DIET AND MANAGEMENT IN A SITKA SPRUCE PLANTATION IN CENTRAL SCOTLAND

The ancestral habitat of capercaillie in most of its range is Scots pi ne forest with an understorey of blaeberry. Keillour forest in Perthsh ire is dominated by Sitka spruce, has little blaeberry, yet had a high density of capercaillie. Food and habitat use by capercaillie were st udied there from 1991 to 1994. Seven cocks and two hens were caught, a nd marked with small radio transmitters. The habitats they occupied an d food remains in their droppings provided information on home range, habitat utilization and diet through the year. Sitka spruce was the ma in food in autumn, winter and spring but was equalled by the fruiting heads of sedge in summer. Larch was the second most abundant item in s pring and autumn diets. Sedge was plentiful on the wet restocks associ ated with the gleyed soils at Keillour and may provide a partial subst itute for blaeberry in summer. Capercaillie showed a clear preference for the oldest blocks of trees, especially in winter. Sitka spruce, No rway spruce and Scots pine were used roughly in proportion to their av ailability in the birds' home range, but larch stands were used more t han expected from availability. In summer, all birds used restocks to some extent. Management recommendations to encourage capercaillie in c ommercial plantations largely comprising exotics are that mature stand s over 45 years and well-vegetated restocks should each occupy at leas t 20 per cent of the forest, larch and blocks of mixed conifers each a t least 15 per cent of the ground. Blaeberry should be encouraged and, if possible, patches of windthrow involving living trees with the mai n root intact should be retained.