Presenter: Ceci Rigby
Authors: Ceci Rigby, Elsa Godtfredsen, Amy Iler
Faculty Advisor: Amy Iler
Institution: Westminster College
High elevation plant ecosystems are heavily dependent on snowmelt for maintaining spring soil moisture levels. As climate change alters traditional weather patterns and reduces snowpack, snow is melting earlier and altering flowering phenology. With this change in flowering time potentially exposing plants to increased physical stressors including drought and frost, changes in floral characteristics may consequently affect pollination. This study aimed to understand the impacts of climate change-induced early snowmelt on the pollination of four subalpine plant species at the Rocky Mountain Biological Lab of Gothic, Colorado in the summer field season of 2021. I conducted pollinator observations to assess pollination within manipulated early snowmelt plots and control plots upon four wildflower species that flower at different times throughout the summer:Delphinium nuttallianum,Linum lewisii, Hymenoxys hoopesii,andDelphinium barbeyi. I hypothesized that the early snowmelt’s potential stressors upon floral characteristics will lead to lower pollinator visitation rates and a higher probability of visitation than control plants. Plants in the early snowmelt plots had significantly lower pollinator visitation rates and probability of receiving a visit on three of the four species studied. These results are concerning as snowmelt timing continues to advance in alpine and subalpine ecosystems. Decreases in viable pollination can lead to decreases in plant reproduction, potentially leading to falls in population size over time. More research into possible explanations for this decreased rate in visitation, such as how drought stress impacts floral rewards, can help us better understand potential long term consequences that earlier snowmelt will have on subalpine plant and pollinator populations.