Seeing through the static: Within-season temporal dynamics of plant-pollinator interaction networks

Background/Question/Methods . Ecological networks are largely characterized as temporally static entities, thereby implicitly assuming that interactions among species are fixed. This static approach has obscured our understanding of the timescale at which interactions form and dissolve, the drivers and consequences of such dynamics, and our general understanding of the interactions themselves. Here, we explore the within-season temporal dynamics of plant-pollinator interactions from weekly censuses across three years in a subalpine ecosystem in Colorado. We investigate the temporal turnover of these interactions as the season progresses, the relative importance of interaction rewiring (the reassembly of interactions among species), and what ecological factors may be underlying such temporal dynamics. We then explore the consequences of these temporal dynamics for our general understanding of ecological networks and species interactions.

Results/Conclusions . We find that changes in the phenology and abundance of plants and pollinators across the season is a major factor underlying the magnitude of interaction turnover and the frequency of interaction rewiring. When examining the topological features of these ecological networks, we find that many measures are inaccurate when the interactions are pooled across the entire season. Finally, at the scale of individual species, we find that interactions can vary widely––from relatively generalized to completely specialized––as the season progresses. Our findings highlight the diversity of species interactions that may be missed when the temporal dynamics of networks are ignored.