Abstract

As biodiversity is declining, the dynamics of species interactions is a growing conservation concern. However, estimating and monitoring species interactions across large spatial and temporal scales remain challenging, and thus changes in species interactions and the subsequent networks of interactions remain relatively unexplored. Here, we assess changes in the network structure of common bird communities from France. We estimate associated species pairs using spatial and temporal information for 109 species monitored across 1,969 sites during 17 years. We validate the ecological significance of associated species pairs by testing the relationship between the propensity to be associated and species functional proximity or shared habitat preference. We reconstruct association networks for these intra-guild bird communities and track temporal changes in network layout in terms of size, density of links, modularity and degree distribution. We show that, beyond species change, birds' local association networks become smaller with a similar relative number of associations that becomes unevenly distributed. These structural changes vary among types of bird communities and may impact community functioning and how communities can cope with global change.