Short-term temperature variation influences the occurrence of plant-pollinator interactions

Background/Question/Methods

Ongoing patterns of global climate change have been linked to numerous disturbances in plant-pollinator communities. For instance, temperature influences the abundance and distribution of both plants and pollinators, and variation in temperature can have important negative impacts for the long-term persistence of both guilds. Temperature variation has also been connected to changes in the floral resources available to pollinators, and the physiology and behaviors of those pollinators. However, empirical evidence is lacking for the effects of temperature at the level of plant-pollinator interactions themselves. In this study, we compare the occurrence of plant-pollinator interactions at four sites in the Rocky Mountains to fine-scale measurements of temperature at the time of those interactions. We expect that thermal optima among both plants and pollinators will result in hump-shaped curves, in which interaction occurrence generally peaks at moderate temperatures across taxa. However, we also expect that temperature represents an axis of niche space, with specific plants and pollinators experiencing different peaks of these interaction probability curves. Such patterns may provide evidence of thermal niche partitioning and lay the groundwork for addition studies exploring the effects of temperature on plant-pollinator community structure and persistence.

Results/Conclusions

While data collection and analysis are ongoing for this project, preliminary results suggest that temperature is indeed an important predictor of plant-pollinator interaction occurrence. Further, the relationship between temperature and interaction occurrence in our study varied substantially among different plant-pollinator interactions. This variation offers potential evidence of a role for temperature in niche partitioning within plant-pollinator communities. We continue to work on analyses to support our supposition that thermal niche partitioning may be at play in this system, as well as to connect these results to the stability and persistence of plant-pollinator networks more broadly. We anticipate that these results will offer important insights into the connection between environmental conditions and the interaction patterns comprising plant-pollinator communities.