Abstract

Bird community responses to local and landscape variables in the city of Santiago, Chile. Urbanization has transformed the landscape affecting ecosystems around the planet. To provide scientific evidence for the conservation of birds in urban environments, we evaluated bird community responses to local habitat and landscape variables in Santiago city, the capital of Chile. We evaluated 118 sites (1 km2 in size) distributed throughout the city, which varied in cover and aggregation of woody cover. At each site, we recorded birds and environmental variables at four sampling points during the breeding and non-breeding seasons. Using community indices (Shannon's diversity and Pielou's evenness), we quantified the effect of landscape variables (percent and aggregation of woody vegetation cover) on the bird community. Then, we identified bird guilds, categorized according to diet, foraging substrate, nest substrate and body size. Using canonical correspondence analyses, we observed relationships between bird guilds and environmental variables quantified at the local and landscape scales. We recorded 42 species of birds. We found more diverse and equitable bird communities the higher the cover and aggregation of woody vegetation in the landscape. Granivorous and ground foraging birds dominated the assemblage, being positively associated with the built environment. Vegetation cover at the local and landscape scale had positive effects on most of the identified guilds, including invertebrate-feeding birds, omnivores, carnivores, nectarivores, vegetation foragers, vegetation nesters, ground nesters, nest parasites, medium-sized, and very large birds. Our results show that the bird community responds to environmental variables at local and landscape scales. Greater vegetation cover in cities would contribute to greater diversity and evenness of the bird community, promoting the abundance of different guilds, including those sensitive to the built environment.