Species-Area Relationships in Urban Ponds Differ between Wild and Human-Fed Domesticated Birds

Abstract

We sampled 70 urban ponds (0.001 to >1 ha) in Rome, Italy, to obtain richness and abundance data for wintering wild birds and domestic birds in relation to pond size. The aim was to test the hypothesis that the species-area relationship differs between wild and domestic birds, with the presence of the latter linked with anthropogenic factors, not pond area. We detected eight domesticated avian taxa and 19 wild species at 26 sites. Whereas there was a significant relationship between the number of wild bird species and pond area, the diversity of domestic taxa appeared not to be correlated with area (power function; Levenberg-Marquardt approach). Species-area relationships showed a lower variance in domestic taxa when compared with wild species. As smaller ponds in urban landscapes can host a higher number of domestic taxa than wild species, there may be implications both for increasing risk of disease transmission and for biodiversity perception among urban citizens.