© Marcel Burkhardt
Thiel, D., E. Ménoni, J.-F. Brenot & L. Jenni (2007)
J. Wildl. Manage. 71(6):1784–1792
The capercaillie (Tetrao urogallus) in Central Europe is an endangered species of grouse that is thought to be highly susceptible to human disturbance, possibly causing local populations to decline. We investigated the behavioral response of capercaillie in the Black Forest, Germany, and the French Pyrenees to an off-trail hiker by measuring flushing distances. Flushing distance varied with capercaillie sex, visibility of the hiker, intensity of winter tourism, and hunting pressure. Independent of the study area, males flushed at consistently longer distances than females, and lower visual blocking between bird and hiker resulted in longer flushing distances. Capercaillie flew at longer distances from an approaching hiker in areas with high intensity of winter tourism or hunting pressure than in undisturbed areas. We recommend the establishment of regulations requiring hikers to stay on trails and to close trails where intertrail distances fall below 100 m (90% of all flushing events appeared within 50 m). Furthermore, planting or preserving evergreen conifer trees in dense rows along critical parts of disturbance sources, reducing the degree of visibility between capercaillie and recreationists would increase habitat for capercaillie in forests with predictable recreation activities.
Keywords: capercaillie, flight initiation distance, human disturbance, stress, tourism, Western Europe.