Six decades of change across all North American bird interaction networks

Abstract

Species interactions are essential for maintaining biodiversity in the face of global changes. Yet lack of interaction data has hindered progress in understanding spatiotemporal changes in ecological network structure and function. To address this shortfall, we perform network analysis on a continental-scale metanetwork of bird interactions (AvianMetaNetwork), and quantify shifts in trophic, commensalism, parasitism, competition, mobbing, and facilitation networks using 13762 interactions among 687 North American birds. Since 1970, changes in species abundance and human activity drove network shifts, especially in eastern North America. With this metanetwork, we uncovered more than a half century of previously undocumented shifts in the structure of each avian network at a continental scale, with large implications for the functioning of bird communities and the ecosystems that rely on them.