Urban bird assemblages in India: the role of traffic, greenspaces, and dietary traits in shaping community composition

Abstract The urban communities of birds in tropical regions are generally understudied, despite these areas hosting most of the bird diversity worldwide. Therefore, understanding the factors that influence tropical urban bird communities is crucial. This study explores ecological patterns of avian communities in the India’s district of Karnataka. A variety of urban settings with different human populations were surveyed to account for the geographical variability of the bird assemblages in the region. Additionally, this study concentrated on the common but often overlooked urban environments– building structures and street vegetation. Using generalized linear mixed models, this study revealed that the most important environmental factor impacting the species richness and diversity of bird communities was the number of motor vehicles, likely inducing various kinds of disturbance to birds, and local cover of greenery, which offers foraging and breeding opportunities for birds. This underscores the importance of including quiet, traffic-free green spaces in urban areas. The most significant trait characterizing the species in the surveyed cities was diet: birds with broader dietary preferences were more abundant in urban settings. This result is consistent with knowledge on predictors of urban bird abundance shaping bird communities in Global North cities, implying common drivers acting in urban areas across the globe.