Habitat variability and spatial assemblages of House Sparrows (Passer domesticus) along a gradient of urbanization

Abstract

House sparrows (Passer domesticus) have declined world over, with their presence rarely seen in cities. Urbanization has lead to significant changes in the population biology of the species affecting their structure and community composition. We investigated the spatial and temporal distribution of House sparrow in various landscapes and the role of habitat attributes along a gradient of urbanization to uncover their possible sites of nesting and habitat preferences. With the study, we report that urban centres have lost favourable nesting habitats for House sparrows and they have locally migrated to the suburban and rural parts of the city. House sparrow abundance was higher in the suburban landscapes, compared to the rural and urban landscapes. House sparrow in the urban occupied a broader niche breath, than the populations in the sub urban and rural matrix. In the urban, the most preferred habitats of the House sparrow were residential areas with tiled and thatched roofs, in the sub urban, rice mills were most preferred and in the rural landscapes residential areas with tiled and thatched roofs and rice mills were equally preferred by the species. Our results revealed that along the gradient shrub cover, built up cover, socio economic status and economic prosperity were positively related to the abundance of House sparrow populations. We summarize the possible decline of Passer domesticus due to lack of insectivorous and granivorous food in the urban, lack of nesting sites and non availability of straw. We suggest to the urban planners and city managers to built urban structures that are eco-friendly to sparrows which can host viable nesting sites for the species.