Development of winter outdoor leisure activities in areas of high natural value is a key issue in the sustainable use of mountain environments. Ski touring, an emerging outdoor activity in the Tatra Mountains, is believed to affect protected mammal species such as the Tatra chamois (Rupicapra rupicapra tatrica), alpine marmot (Marmota marmota latirostris), red deer (Cervus elaphus), European roe deer (Capreolus capreolus), brown bear (Ursus arctos), and red fox (Vulpes vulpes). To assess the impact of ski touring on these species, various studies are underway in Tatra National Park. The aim of this study was to investigate the interactions between ski tourers and large mammals in the park using a social science approach. A total of 274 skiers completed an online questionnaire about their encounters with large mammals during their ski tours in Tatra National Park and their perceptions of animals' reactions to their presence. Just over half of the respondents reported encounters with large mammals—most often with chamois, followed by deer (red or roe), foxes, and marmots. Only 6% reported encounters with brown bears. The most commonly reported animal reactions were vigilance and indifference (no reaction). Flight or aggression occurred less often—in about 22% of encounters with all species and 12% of encounters with chamois. An online survey on human–wildlife interactions can provide a cost- and labor-efficient complement to field research such as direct observation, GPS tracking, and physiological testing.