Burning and mowing as habitat management for capercaillie Tetrao urogallus: An experimental test

Capercaillie Tetrao urogallus benefit from abundant bilberry Vaccinium myrtillus, and associated invertebrates, which are important to foraging broods. We tested burning and mowing, as means of increasing bilberry, at a Scottish pinewood with ericaceous ground vegetation. After six years, bilberry cover in burnt and mown areas was about 35% more than that of controls. The biomass of spiders, which are taken by capercaillie chicks, also increased in burnt and mown areas. Burning and mowing, in habitats similar to those of our study site, are techniques that are likely to help capercaillie conservation. [Display omitted] ► Capercaillie Tetrao urogallus benefit from abundant bilberry Vaccinium myrtillus. ► We tested burning and mowing, as means of increasing bilberry. ► After 6 years, bilberry cover in burnt and mown areas was ∼35% more than controls. ► Abundance of spiders, taken by capercaillie chicks, also increased. ► Burning and mowing are techniques likely to help capercaillie conservation. In Scots pine Pinus sylvestris forests, the important ecological effects of natural fires could be emulated using prescribed fire. Species that may benefit from fire effects include capercaillie Tetrao urogallus, a large forest grouse. A key component of forest habitats for capercaillie is the ericaceous shrub, bilberry Vaccinium myrtillus, which is eaten by capercaillie, and supports abundant arthropods, taken by young chicks. We carried out an experiment testing whether prescribed burning would be a valuable technique for capercaillie habitat management. The study took place at Abernethy Forest, the largest ancient native pinewood in Britain, and a key capercaillie site, holding c 8–20% of the British population. Prescribed fire in woodland is highly novel in Britain. We therefore also tested mowing, which might replicate some fire effects more cheaply and safely. Twenty-five experimental blocks were established within open pine stands with ground vegetation including bilberry, but dominated by heather Calluna vulgaris. Each block held three 700 m 2 plots, randomly assigned to control, mow and burn. Vegetation, arthropods and capercaillie dung were monitored over a 7-year period, including 1 year prior to treatment. Mean bilberry cover, initially around 12%, increased in mown and burnt areas, but there were also increases in controls, following unusual natural die-back of heather. By the sixth season after treatment, bilberry cover was significantly higher in burnt