Leveraging soundscapes to identify biodiversity’s role in non-material nature’s contributions to multiple social actors

Non-material Nature’s Contributions to People (NCP) are notoriously challenging to quantify due to their reliance on subjective human experiences. Addressing this challenge requires integrative approaches across ecological and socio-cultural perspectives. Soundscapes are a powerful entry point, as they encompass sounds generated by natural environments and are one of the most accessible pathways of nature experience, i.e., listening to nature. By combining bioacoustic methods with analyses of social preferences, this study explores how the acoustic dimension of biodiversity connects people to nature across cultural contexts. Using Mount Kilimanjaro’s diverse soundscapes, we explored how listening to nature shapes non-material NCP experiences among residents and tourists across different habitats. Overall, dawn soundscapes (i.e., morning choruses) were preferred, likely due to the prominence of birdsong and the greater diversity of other sound sources compared to the louder, insect-dominated dusk soundscapes (i.e., evening choruses). However, the specific habitats associated with these preferred soundscapes, and the non-material NCP linked to them, differed markedly between residents and tourists, revealing distinct ways each group experiences nature. Residents favoured soundscapes from habitats where they live and work, such as maize fields, homegardens, and coffee plantations, whereas tourists preferred soundscapes with minimal human-generated sounds, such as those from sub-alpine habitats. Furthermore, soundscapes evoked distinct non-material NCP, such as cultural heritage for residents and restorative experiences for tourists. Linking these perceptions to acoustic indices revealed how different acoustic properties of biodiversity support seven out of the eleven non-material NCP assessed. For instance, restorative experiences were associated with soundscapes that balanced acoustic evenness and complexity (i.e., birdsong-rich but not acoustically saturated), whereas aesthetic experiences were linked primarily to high acoustic complexity, even in highly saturated soundscapes (i.e., diverse vocalizing species). Associating non-material NCP with specific habitats further showed that local residents also value soundscapes within the protected area, despite access restrictions. These restrictions can erode the significance of otherwise culturally salient places and hence weaken local support for nature protection when local perspectives are ignored. By connecting experiential, sensory, and ecological dimensions, this research provides empirical tools and conceptual pathways to strengthen non-material NCP research and embed its insights into decision-making.