Are urban bird communities influenced by the bird diversity of adjacent landscapes?

1. The species diversity of adjacent landscapes influences the conservation or restoration of several animal groups in urban areas, but the effect on birds is unclear. To address this question, we compared bird species richne ss (BSR) and community composition between periurban (area surrounding the town) and urban (suburban and centre areas) landscapes across three spatial scales. 2. At a large biogeographical scale (temperate and boreal climatic zone), r elationships between the BSR of urban areas and their surrounding landscape s were examined in a meta-analysis of 18 published studies. In general, BSR was negatively correlated with latitude and urbanization. The BSR of subur ban and centre landscapes correlated positively with the BSR of periurban l andscapes. However, latitudinal effects were also involved, as BSR in urban and periurban landscapes declined as town latitude increased. Similarity i ndices were low (50%) between periurban and centre bird communities. 3. At a regional scale, we assessed winter bird data from several towns wit hin three regions of temperate and boreal countries (western France, northe rn Finland and eastern Canada). The type of periurban landscape., number of inhabitants and town diameter did not affect BSR. BSR was similar between the cities of a given biogeographical area. Bird communities were more simi lar between similar habitat types of different cities than between differen t habitats of the same city. 4. At a local scale, we tested the influence of proximity to the periurban landscape on BSR in parks of western French towns of different size. Neithe r BSR nor community similarity changed in relation to the distance of the p ark from the periurban landscape. 5. Guild composition according to diet and feeding habitat did not vary bet ween urban and periurban locations at regional or local scales. 6. We conclude that, at regional and local scales, urban bird communities a re independent of the bird diversity of adjacent landscapes, and that local features are more important than surrounding landscapes in determining BSR . Whatever the biodiversity quality of the periurban landscape, site-specif ic actions such as shrub and tree planting, water restoration and increasin g vegetation diversity can change bird diversity in towns and improve the q uality of human-wildlife contacts.