Urban bird richness and abundance are responding to different scales of the same city
WHAT THE EVIDENCE SAYS
Across 12 urban-forest parks and 111 matched spatial units in three Italian cities, researchers recorded 2,035 birds from 52 species. Local tree density, crown structure and vertical heterogeneity were more strongly associated with species richness and functional diversity, while total abundance responded more to landscape-scale aggregation and land-cover diversity; several relationships were nonlinear.
WHY IT MATTERS / OUR READ
Urban forest design has more than one ecological scale. Retaining complex stand structure can serve a different part of the bird community than improving landscape connection or surrounding land-cover pattern, so ‘more green’ is a weak substitute for asking which response the design is meant to support.
CAVEATS / UNCERTAINTY
The study is observational, uses Random Forest/SHAP associations rather than experimental treatments, and focuses on forest-associated birds in three Mediterranean cities. City and year coverage were limited, and associations should not be read as universal causal prescriptions for urban planting.
SOURCE
Urban Ecosystems — primary study
View original evidence ↗
Across 12 Italian urban forests, local stand structure was more associated with richness and functional diversity, while bird abundance tracked larger-scale landscape configuration more strongly.
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