Using citizen science observations to monitor urban biodiversity

A multi-taxa framework scoring species by their urban tolerance and towns by their "biodiversity urbannness"

Data resources used via GBIF : 643,000 species occurrencs

Monitoring the response of biodiversity both to threats and to restoration efforts, is essential but expensive. Broad-scale citizen science may play an important role in understanding how to best preserve and manage biodiversity in the future.

This study uses 643,000 observations in the Boston Metropolitan region, shared through iNaturalist and published in GBIF, to study the effects of urbanization on biodiversity, scoring more than 1,000 species by night-time light levels at occurring sites—derived from a remote sensing infrared imaging dataset—as a proxy for urban tolerance.

Among the most urban species were Japanese creeper (Parthenocissus tricuspidata) and northern seaside goldenrod (Solidago sempervirens), while the least tolerant were Canadian bunchberry (Cornus canadensis) and frosted whiteface (Leucorrhinia frigida). The analysis highlighted a clear difference between native and non-native species, as the mean urban score was almost three times higher for non-natives.

Using the species-specific urban scores, the study then assessed 87 towns in the region by the community of species observed, ranking them by "biodiversity urbanness". This analysis revealed no bias among observers for more urban species but showed that biodiversity urbanness is negatively correlated with EVI (enhanced vegetation index) but positively correlated with the mean impervious surface of a town.

Overall, the study showcases how citizen science data can be leveraged for monitoring urban biodiversity and its responses to increased urbanization.

Callaghan CT, Ozeroff I, Hitchcock C and Chandler M (2020) Capitalizing on opportunistic citizen science data to monitor urban biodiversity: A multi-taxa framework. Biological Conservation. Elsevier BV 251: 108753. Available at: