Identifying, surveying and monitoring urban biodiversity through citizen science in the Siena BiodiverCity project

Urban biodiversity citizen science projects remain relatively rare, despite the potential of cities as living laboratories for studying ecological patterns and the effects of urbanization on various taxa. The Siena BiodiverCity (SBC) project was launched in 2022 with the aim of identifying, surveying, monitoring and promoting urban biodiversity in Siena, Italy through citizen science. The project’s main activities include 1) an annual City Nature Challenge BioBlitz that brings together residents and expert naturalists to survey wild organisms; 2) educational biodiversity workshops and urban field trips to educate citizen science practitioners in biodiversity sampling and identification; 3) hands-on practical classes to raise peoples’ awareness about the importance of urban ecosystem services (especially pollination); and 4) establishment of a Biodiversity Desk for specimen identification. These efforts have raised local awareness about urban biodiversity and its functions and built a collaborative network among residents, environmental and socio-cultural associations, and scientific institutions. In three years, more than 500 local community members have participated in SBC events; over 8000 observations of more than 1600 taxa have been collected through iNaturalist, especially since the launch of the project in 2022. Beyond this, SBC supported Siena for the certification as Italy’s first eco-sustainable city of art by Global Sustainable Tourism Council, inspiring urban planners to increasingly include biodiversity in city development. In 2023, the project expanded, helping the Municipality of Siena win a European partnership grant aimed at fostering urban biodiversity through community-based approaches. This initiative serves as a replicable model for similar projects and underscores the transformative potential of urban citizen science to empower communities to actively explore and monitor their natural surroundings, while supporting city institutions in managing, restoring, and improving urban planning strategies.