Local impacts of global change: shifting range limits, advancing phenology, and communicating research

Thesis (Ph.D.)--University of Washington, 2016-06

There are two generalizable biological impacts of climate change: first, species are shifting their distributions (both pole-ward in latitude and up in elevation), and second, species are advancing their spring phenology. Climate change is having these effects because climate controls both where species exist and when species reproduce. However, a significant gap in our knowledge are the causes and consequences of species-to-species variability in their responses to climate change, which I address in my first two chapters. In Chapter One I ask: what role (if any) do pollinators play in establishing the range limits of one subalpine flowering plant (published in American Journal of Botany, 2016). I find that in some years, fruit and seed set is limited by pollinators at the high-elevation range limit, suggesting that pollinators may contribute to how far uphill this plant can expand its range, and how rapidly range shifts occur. In Chapter Two I ask: what are the community-wide implications of individual species-specific phenological advance. I find that all species are sensitive to climate (primarily snow disappearance date and growing degree days, and a lesser degree soil moisture draw-down) but that they advance non-uniformly which causes phenological community reassembly in climate change-like conditions. This reassembly causes plants to co-flower in novel ways, and has the potential to alter species interactions both within and between trophic levels. Finally, in Chapter Three, I attempt to make the biological impacts of climate change (like the range shifts and phenological shifts I address in my first two chapters) more relevant to the general public, by asking if it is better to teach (undergraduates) by using local or global examples of climate change’s biological impacts (published in Frontiers in Ecology and the Environment, 2015). I find that a single in-class activity increased students’ content knowledge and leads students to more-strongly believe climate change would alter their lives, to show more willingness to alter their behavior, and to more strongly support government action. Interestingly, I also found a strong gender effect on the influence of local vs. global examples: females learned more if they studied local examples. Together, this work highlights the importance of considering how species interact with their neighbors and environment when assessing the biological impacts of climate change and the importance of implementing evidence-based teaching practices.