Avifaunal diversity in urban parks of Delhi is shaped by both anthropogenic and natural factors

Urbanization leads to fragmentation and reduction of natural habitats which become islands of remnant biodiversity. As predicted by the Theory of Island Biogeography (TIB), fragment area and fragment isolation are major predictors of bird species richness in urban and rural habitats. This study is to understand patterns in avifaunal composition in select urban parks specifically in terms of area and size effect. To assess this, alpha and beta diversity indices were calculated and compared. Species–area curves were generated to test the relevance of TIB, and correlations were examined between species abundance, park area, and proximity to forested patches. Overall, the findings suggest that TIB alone is insufficient to explain avifaunal diversity in urban context. Instead, factors such as vegetation complexity, habitat age, human disturbance, and park management appear more significant, highlighting the multifaceted nature of urban ecological dynamics. This study demonstrates that small urban parks can support surprisingly rich avifaunal diversity, even in densely populated cities. The urban ecological future depends on recognizing and nurturing these green fragments as critical spaces for biodiversity.