Utilizing Parnassius clodius butterflies and nectar plant species to evaluate ecological responses to climate change

Abstract

Climate change is a pressing global issue leading to species declines, altering species interactions. Changing environmental conditions result in species adaptation or movement to suitable areas. High elevations and latitudes are susceptible to rapid change, potentially leaving no refuge for species. Plants and pollinators are particularly vulnerable to changing environmental conditions with their life cycles dependent on the timing of environmental cues that initiate species morphology, physiology, and behavior patterns. A disruption in a species' typical life-cycle pattern may lead to phenological shifts affecting biological events potentially inducing phenological mismatches between interacting species. This research addresses (1) how current and predicted environmental conditions affect the population growth rate of Parnassius clodius butterflies, (2) investigates the effect of warming and advanced spring snowmelt on arrowleaf balsamroot phenology and morphology, and (3) understands the effect of warming on the phenology, morphology, and photosynthetic performance of three prominent native flowering species in the Rocky Mountain Region. A mark-recapture-release program paired with life-stage hypothesis modeling was used to evaluate population growth rates of Parnassius clodius. Plots with plant species of interest were experimentally manipulated (warming, snow removal) and phenology, morphology, and photosynthetic performance of individuals monitored and evaluated using mixed-effects models. Findings from this dissertation determined that (1) extreme maximum temperatures during the spring led to decreased population growth rates of Parnassius clodius butterflies, (2) heating via passive warming and advanced spring snowmelt via snow removal led to earlier flower onset, extended flowering durations, and more flowers produced by arrowleaf balsamroot, and (3) there was no real effect of our heating treatment, but rather species-specific phenological, morphological, and photosynthetic performance differences with extended flowering durations among yarrow and geranium, more flowers produced by geranium, the greatest photosynthetic performance by yarrow followed by geranium, and maximum soil moisture, soil temperature, air temperature, and surface temperature were the best predictors of photosynthetic performance. Additionally, an iBook science communication tool was produced. These findings suggest that floral communities are faring better under a changing climate with more sensitive butterfly counterparts facing declines. Overall, this could lead to cascading effects on floral populations due to declining butterfly populations.