While the occurrence and function of vocalisation by pikas has been studied (genus Ochotona), little is known about vocalisation by hares (genus Lepus). In this study, we investigate the vocalisation activity of mountain hare (Lepus timidus) over the course of a year to better understand its occurrence and function. We found that mountain hares have a low vocalisation rate of one vocalisation every 33 night hours. We hypothesise that this low rate is the result of a strategy to minimise detection by predators. However, the 20 recorded vocal events correspond with intraspecific communication events such as warning others about danger and defending resources. This case study identifies further research directions to help strengthen our understanding of communication between solitary hares.