In the Shadow of Man: Behavioral Changes in Japanese Pika (Ochotona hyperborea yesoensis) due to Human Presence at Mount Highashi-Nupukaushi-Nupuri, Hokkaido, Japan

Wildlife often perceives humans as a threat, which can affect their behavioral ecology and alter their fitness and survival. Studying these behavioral responses can help to evaluate the impact of human activities. We studied the effects of human presence on the anti-predatory behavior of the Japanese pika, Ochotona hyperborea yesoensis, a small mammal found in rocky montane areas of Mount Highashi-Nupukaushi-Nupuri, Daisetsuzan National Park, Hokkaido, Japan, during the summer season (May to August) of 2022 and 2023. We compared the tolerance or habituation behavior of pikas at the control site with no human interference and at the impact site with human visitation, where we recorded the calling and flight initiation distance of pikas when approached by researchers. The Spearman correlation coefficient (Shapiro–Wilk test, p < 0.05) indicated a significant positive correlation between the distance of pikas from the trail and both the calling initiation distance (r = 0.731, p < 0.001) and flight initiation distance (r = 0.860, p < 0.001). Pikas at the control site produced a significantly higher proportion of calls in the presence of humans than pikas at the impact site. Furthermore, at the impact site, repeated encounters with humans reduced the calling and flight initiation distances of the pikas; that is, the pikas were bolder and quieter when approached by humans compared to the pikas at the control site. Our research highlights the potential impact of increased human visitation on pikas behavior, highlighting the urgency of sustainable conservation efforts.