Effect of Urbanization on the Abundance and Distribution of Tree Sparrows (Passer montanus) in Beijing

Abstract

With rapid urbanization occurring throughout China, the existence of Tree Sparrows (Passer montanus) in big cities is likely to be affected by a decrease in habitat and food availability. Can the urban Tree Sparrow adapt to these changes? To elucidate this question, we studied the effect of urbanization on the abundance and distribution of Tree Sparrows in Beijing. We found the abundance of the Tree Sparrow negatively correlated with an urbanization score. Sparrow abundance was very low in residential areas with high-rise buildings, commercial centers and main roads, while their numbers were significantly higher in parks, university campuses, low building residential and suburban areas. Environmental factors within the 50 m and 200 m scales were most suitable in predicting the distribution of Tree Sparrows during winter, while factors with in 50 m and 400 m scales are suitable during the breeding season. During winter, the number of conifer trees and pedestrians were the major factors at the 50 m scale, while the area of high-rise buildings and vegetation become the predominant factors on a 200 m scale. Alternatively, during the breeding season the area of low buildings and the number of conifers and pedestrians were the main factors on the 50 m scale while the area of high-rise buildings and vegetation remained the most important factors on the 400 m scale. These results indicate that highly urbanized areas are not suitable habitats for the Tree Sparrow, although this species can adapt to human environments. Food and nest sites for urban birds should be considered in urban planning of big cities in developing countries.