Plant-pollinator interactions under climate change: The use of spatial and temporal transplants

Abstract

Climate change is affecting both the timing of life history events and the spatial distributions of many species, including plants and pollinators. Shifts in phenology and range affect not only individual plant and pollinator species but also interactions among them, with possible negative consequences for both parties due to unfavorable abiotic conditions or mismatches caused by differences in shift magnitude or direction. Ultimately, population extinctions and reductions in pollination services could occur as a result of these climate change-induced shifts, or plants and pollinators could be buffered by plastic or genetic responses or novel interactions. Either scenario will likely involve altered selection pressures, making an understanding of plasticity and local adaptation in space and time especially important. In this review, we discuss two methods for studying plant-pollinator interactions under climate change: spatial and temporal transplants, both of which offer insight into whether plants and pollinators will be able to adapt to novel conditions. We discuss the advantages and limitations of each method and the future possibilities for this area of study. We advocate for consideration of how joint shifts in both dimensions might affect plant-pollinator interactions and point to key insights that can be gained with experimental transplants.

Keywords: climate change; phenology; plant–pollinator interactions; pollination; transplants.

Fig. 1.

Conceptual depiction of phenological and distributional shifts in populations of plants and pollinators under climate change, with populations depicted as single icons (after Alexander et al., 2016). The timing of flowering for plants and activity for pollinators is represented as shades along a color scale. Pre–climate change distributions are shown in gray. (A) Positions occupied by populations pre–climate change (historical baseline). (B) Phenological/temporal shifts alone. (C) Distributional/spatial shifts alone. (D) Joint phenological/temporal and distributional/spatial shifts. (B–D) Each panel illustrates possible outcomes of shifts: (i) maintenance of historical interactions (indicated by O), (ii) loss of historical interactions (indicated by –), and (iii) gain of novel interactions (indicated by +). For simplicity, population abundances and shapes of distributions are not shown. Although some shift types in this figure appear to be less severe than others (D changes one interaction and maintains another, while C loses both interactions), these are intended only as example outcomes. The severity of the outcome will vary depending on the pre–climate change situation, the degree of shifting of each population, and many other factors.