Understanding drivers of global urban bird diversity

Around 56% of the world's population live in cities, with rapid urbanisation in developing regions. However, most ecological studies focus on developed countries. Here, we conduct a global analysis on bird diversity for 48,180 cities and assess the drivers of avian diversity. Productivity is one of the best indicators of diversity across biomes, but forest-cover only becomes important in biomes with less tree-cover. Important factors also vary based on city-size, though access to green-space is uniformly a major driver of diversity worldwide. Conversely, percentage of impermeable surfaces, night-time light and population density are nigh-universally negative drivers. Green space becomes increasingly important in larger cities. Space-management dramatically increases the ability of cities to host high bird di-versity, highlighting the need for data-driven approaches to facilitate greener-development.

Automated summary

Most ecological studies focus on developed countries, but the rapid urbanisation in developing regions has significant implications for biodiversity. This global analysis reveals that city size and environmental characteristics have varied impacts on bird diversity, but access to green space is a major driver worldwide.