The role of urban waterbodies in maintaining bird species diversity within built area of Beijing

This study aims to provide a comprehensive understanding of the role of urban waterbodies in avian ecology, which is instructive for both biodiversity conservation and urban planning. Based on bird surveys conducted in 41 urban parks in Beijing during the breeding and wintering seasons of 2018-2019, and using standardized regression analyses, we identified the specific effects of waterbody attributes on the full avian community and forest bird guilds. We assessed this at multiple spatial scales, first within the focal parks, and then within buffer zones with radius of 200 m and 1000 m. We found that waterbodies can serve as avian diversity "hotspots" in the urban landscape. More specifically, they support avian diversity in the following ways: (1) Parks with waterbodies maintain a higher number of bird species than parks without waterbodies during the breeding season and attract resident forest birds during the wintering season. (2) When not frozen, waterbodies inside and outside parks contribute equally to resident forest bird species richness, while more individuals were attracted by waterbodies within neighborhoods. (3) In parks without waterbodies, the number of forest bird species significantly increases with the number of waterbody patches within neighborhoods, while the corresponding relationship for parks with waterbodies is insignificant. These findings suggest a preference for habitats nearby waterbodies among forest birds residing highly urbanized areas. This study provides new insights into avian ecology in urban landscapes and scientific support for the idea that creating and maintaining urban waterbodies can conserve biodiversity.