Summers, R.W., McFarlane, J. & Pearce-Higgins, J.W. 2007: Measuring avoidance by capercaillies Tetrao urogallus of woodland close to tracks. - Wildl. Biol. 13: 19-27.
We carried out a study in four stands of Scots pines Pinus sylvestris at Glenmore Forest and Abernethy Forest, Scotland, to measure distances over which capercaillies Tetrao urogallus avoided woodland close to forest tracks (gravel roads designed for vehicles, but also used by recreational walkers and cyclists) during autumn and winter. Tracks with low and high human use were selected in the two forests, and the presence of capercaillie droppings under trees gave ameasure of use for feeding at different distances from the tracks. At all sites, the use of trees by capercaillies was lower close to tracks. The amount of woodland effectively avoided by capercaillies ranged from 1 ha per 46 m of track to 1 ha per 82 m of track at the different sites.Given the high density of tracks atGlenmore and Abernethy Forests (1,950 m/km² in both forests), the percentage of woodland avoided by capercaillies ranged within 21-41%. A likely explanation is that human activity in these small native pinewoods is disturbing capercaillies, and may reduce their carrying capacity. Possible micro climate or predator effects were discounted.
Key words: capercaillie, forest management, National Parks, pinewoods, Pinus sylvestris, recreational disturbance, Tetrao urogallus
Ron W. Summers & Joanna McFarlane, Royal Society for the Protection of Birds Scotland, Etive House, Beechwood Park, Inverness, IV2 3BW, UK - e-mail addresses: ron.summers@rspb.org.uk (Ron W. Summers); Jo.McFarlane@rspb.org.uk (Joanna McFarlane)
James W. Pearce-Higgins, Royal Society for the Protection of Birds Scotland, DunedinHouse,Ravelston Terrace, Edinburgh, EH4 3TP,UK- e-mail: James.Pearce-Higgins@rspg.org.uk
Corresponding author: Ron W. Summers
Received 26 July 2005, accepted 1 December 2005
Associate Editor: Ilse Storch