Discipline: Ecology Environmental and Earth Sciences
Room: Exhibit Hall A
Rustin Bielski - Salish Kootenai College
Native pollinating bees are a vital component of the biologically diverse plant and animal community, which is critical to healthy, ecologically functional landscapes. According to the Xerces Society for Invertebrate Conservation, five species of bumble bees in North America are now listed as critically endangered. Though, even as they are declining, they continue to be keystone pollinators of native food plants as they have for thousands of years. Due to its size and diverse landscape, Montana contains the most bumble bee species in the United States. Bumble bee’s endemic to Montana are being reduced in number, while the number of exotic plants is proliferating with many becoming invasive. Recently, Northwest Montana has seen shorter milder winters and longer drier summers, and these changes in climate are anticipated to bolster exotic plants species. As this happens, the question put forth becomes: how will the relationship between bumble bees and their symbiotic plants differ? This study observes the temporal dynamics of bumble bees foraging behavior on native and non-native flowering plants. Data was obtained using paired sample plot focal observations, transect focal observations, and bumble bee capture and analysis. Paired focal observations saw 58% of bumble bees on native flowers and 42% on non-native, however while the abundance of flowering resources were dominantly native 98% of the bees were seen on native plants, and while the majority of flowering resources were non-native only 28% of bees were seen on native plants. Fixed transects and bumble bee captures saw similar results. Originally hypothesized: if within the Mission valley environ, Bombus species prefer common exotic flowering plants as opposed to native flowering plants as a primary source of food at any given time during the blooming season, then this is due to a higher density of flowering resources of non-native flowers over native ones. Throughout the season, if the order of dominant plant type changes, favorability is likely to change toward that of the dominant plant because it is most likely that bees prefer whichever plant is most dominant. This is relatively what was seen during the course of the experiment, however in continuation of this research I would need to devise a better way of accounting for percentages of blooming flowers for a more accurate comparison. As anthropogenic change continues to affect the temporal dynamics of the growing season, bumble bees might have to rely on late season food sources before they can hibernate. Since within the Mission Valley environ this late food source seems to only be recognized in exotic plant species, will they be an asset for bumble bees moving forward or will they be noxious to their survival?
Funder Acknowledgement(s): Funding provided by NSF EAR 1757451
Faculty Advisor: Janene Lichtenberg, Janene_Lichtenberg@skc.edu
Role: All components.