Efficacy of aural detection methods for detecting Northern Pika (Ochotona hyperborea) occupancy in rocky and densely vegetated habitats

Abstract

Abstract Wildlife monitoring plays a key role in species conservation, with growing importance under the threat of climate change. The Northern Pika (Ochotona hyperborea) is a cold-adapted species found in Hokkaido, Japan, presumably vulnerable to such threats. However, its high elusiveness hinders detailed population surveys, and visual detection methods—often used for other pika species—are not applicable to its densely vegetated habitats. In this study, we assessed the efficacy of aural detection methods to survey the occupancy of Northern Pika through their distinct vocalizations. We conducted two types of point-count surveys—auditory observation and playback—during 2021 at 18 sites in and around Daisetsuzan National Park. We then assessed the efficacy of these methods in detecting presence and compared time until first detection of the animal. The Northern Pika was present at 11 of all surveyed sites, with a predominance at higher elevations. Our results suggest that both auditory observation and playback are effective at detecting presence, but playback is more time-efficient. We discuss the advantages and disadvantages of each method given these results. In conclusion, our results demonstrate that both survey methods are applicable for Northern Pika population surveys—even in densely vegetated habitats—representing valid and affordable survey methods that can help to improve current monitoring and conservation efforts, and will be of increasing value given potentially negative effects of climate change on persistence of the species.