Do Green Space Attributes Influence Avian Health? Evidence from the Nutritional and Oxidative Status of a Neotropical Bird

Abstract

Urbanization impacts public, wildlife and environmental health. Studies comparing rural and urban populations reveal negative effects of urban life on animal health, however, there is a paucity of research on its intra-urban variation. Specifically, whether wildlife health varies with green space attributes in cities remains poorly understood, which limits strategies for healthier urban environments. We investigated whether island hills promote a better nutritional and oxidative status than urban parks for a Neotropical bird dwelling in urban areas, and whether vegetation variables influence bird health. In the capital city of Santiago de Chile, we estimated the nutritional status (scaled mass index, residual index, tarsus length and body size index) and oxidative status (level of lipid peroxidation, total antioxidant capacity and an index of oxidative stress) of rufous-collared sparrows ( Zonotrichia capensis ), a native passerine bird. We found that birds living in island hills exhibited better nutritional and oxidative attributes than birds living in parks. Hills providing greater woody plant richness promoted a better nutritional environment and lower levels of oxidative stress in birds. Body size also increased with the percentage of shrub cover of the hills. We found that in parks birds’ body condition also improved with the proportion of native woody species. Our results evidence that bird health is related to green space type and vegetation variables. These results also highlight the importance of conserving large green spaces (island hills), promoting shrub cover and prioritizing native plants in afforestation projects. These planning and management strategies will contribute to achieving healthier urban environments.

Keywords: Body condition, body size, oxidative stress, island hills, parks, Zonotrichia capensis