The co-benefits of biodiversity citizen science for well-being and nature relatedness.

Human well-being is dependent on the health of our planet. Biodiversity-related citizen science supports conservation research, and there is increasing interest in its potential as a health co-benefits intervention. This randomized controlled study investigates the health co-benefits of biodiversity citizen science participation. Seventy participants were randomly assigned to a citizen science project or control group for an 8-month period. Both groups completed pre- and post-intervention surveys, evaluating nature relatedness, self-efficacy related to biodiversity loss, subjective well-being, and climate change anxiety. A subset (N = 13) of participants engaged in the citizen science project also took part in focus group discussions. The intervention group reported a significant increase in nature relatedness and self-efficacy to help address issues of biodiversity loss. Although no significant changes were observed for other well-being or anxiety scales, most participants reported positive outcomes related to mental or physical well-being in focus groups. There were stronger positive effects for participants without previous environmental volunteering experience. These results suggest that citizen science participation has the potential to contribute to Planetary Health goals, with sustained co-benefits for well-being and nature relatedness. Future interventions evaluating co-benefits should consider previous environmental volunteering experience and focus on participants with little experience to maximize health outcomes.