Long-Term Population Trends of House Sparrow and Eurasian Tree Sparrow in Spain

Urban areas are constantly increasing, which can cause an effect in bird populations since human activities lead to nature alterations. Populations of House Sparrow (Passer domesticus) and Eurasian Tree montanus) have been decreasing Spain according the latest national censuses Spain. In this study, we tried assess population trend over more than two decades using ringing data from Spanish constant effort sites, as well determine breeding success proxy relation habitat composition at landscape level. We analysed confirmed species. However, showed signs increasing presence urban areas. Furthermore, productivity remained stable sampling sites years, meaning that causes affecting both adult juvenile individuals.