The present study investigated whether the flushing distance, the territorial use and the stress hormone physiology of the capercaillie (Tetrao urogallus) were influenced in the winter by the presence of a large number of people engaged in sporting activities. In most cases flushing distances were greater, and higher concentrations of stress hormone were found in the blood serum, in areas having a high intensity of sporting activities than in forest stands relatively undisturbed by tourists. During the ski season capercaillie avoided forest patches within their home ranges where there was a high level of recreational activity. The results lead to the conclusion that intensive winter tourism can be a serious threat to the remaining capercaillie populations in middle Europe. It is recommended that the construction of new recreational facilities and new developments should be avoided in the most important habitats for capercaillie. The important habitats which today already lie in the immediate vicinity of areas intensively used by tourists could clearly receive enhanced status, according to each situation, either as tranquility areas for wildlife where entrance is forbidden or with regulations requiring winter tourists to stay on trails.
