Diversity and plasticity of vocalisations in an elusive and arboreal small mammal: the edible dormouse (Glis glis)

The acoustics of small mammals, particularly dormice species, are generally understudied. During this study, we explored the vocalisations and acoustic behaviour of the edible dormouse (Glis glis) in various environments in Catalonia using ultrasound recorders. Up to five different types of calls were identified in various environmental conditions (captivity and free-ranging animals) and developmental stages, from pups to adults. Additionally, one new call type was described. Significant differences were observed between captive and wild dormice (e.g. length of the calls and position of the peak harmonic), enhancing the plasticity of their vocalisations. In addition, ultrasonic sound production was discovered in pups, suggesting ontogenetic changes in the vocal repertoire. The lack of differences in vocalisations between sexes reported in captivity highlight the importance of traditional monitoring methods (i.e. nest boxes) for population monitoring in the case of the edible dormouse. The potential of the acoustic method as a non-invasive tool for studying ecological behaviours and interactions, or early detection of the species in the natural environment is emphasised. This study provides an open call reference library, laying the groundwork for a better understanding of edible dormouse acoustics, and focuses on the importance of future research to explore the acoustic social behaviour of the species.