Distribution of Bird Communities and Habitat Corridor Composition Shaped by Environmental Factors in Urbanized Landscapes: A Case Study in Beijing, China

Urban biodiversity is crucial for ecological security, balance, and important for fostering awareness on human-nature interconnectedness among the public. The diversity of birds, as an urban ecosystem indicator, reflects ecosystem services and is impacted by urban development. To explore the impacts of urbanization on bird diversity, stratified to songbirds, terrestrial birds, climbers, swimming birds, wading birds, and raptors, we specifically investigated the existing and potential distributions of selected bird species, analyzed different contributions of environmental factors, and compared these with urban biodiversity conservation policies. We used bird records from the China Birdwatching Record Center (over 1400 species of birds for querying) and remotely-sensed landcover data, based on the MaxEnt model, to analyze bird spatial distribution characteristics and potential habitat corridors throughout Beijing. The results showed that: (1) Songbirds and terrestrial birds were predominantly concentrated in water areas in urban areas. Wading birds, climbers, swimming birds, and raptors were gathered in forest-covered areas, near wetlands and farmland in suburban areas. Projections indicated that the raptor species Common Kestrel (Falco tinnunculus) showed a notable shift toward urban cores. (2) Among climbers, Gray-headed Pygmy Woodpecker (Dendrocopos canicapillus) occupied the highest proportion of high-quality habitats (10.34%), contrasting with the representative songbird species Blackbird (Turdus merula) at 1.38%, which demonstrated adaptability to urban environments. Critical habitats were concentrated in shrub forests, supporting habitat connectivity. Proximity to water bodies was critical for raptors, wading, swimming, and climbers, whereas terrestrial birds and songbirds were more affected by artificial lighting. (3) The “urban and suburban park rings” policy has effectively enhanced habitat quality and connectivity, promoting urban biodiversity resilience. This study improves our understanding of how different bird communities adapt to urbanization in terms of habitats and movement corridors, and provides useful information for formulating urban bird biodiversity conservation strategies.