Metzger, Sam2024-06-122024-06-122024-06https://hdl.handle.net/1794/2950316 pagesLand use change, invasion of non-native species, and other modes of habitat loss contribute to native bee population declines. A key contribution to population decline may be a loss of nutritional resources, which can occur when landscapes have reduced floral diversity and abundance. Increasing floral resources may mitigate future declines and forest ecosystems may offer necessary food and nesting opportunities for native bees. However, it is unclear whether and how forest management practices influence the capacity of forests to fulfill these roles. Our research advances the field's understanding of bumble bee nutrition as a function of plant community structure by examining it within a forest ecosystem. To do this, we focused on foraging patterns of bumble bees across a gradient of canopy openness in the Oregon Coast Range. With the understanding that bumble bees prefer warm, sunny, fair-weathered spaces with abundant floral resources, we hypothesized (1) there would be a positive relationship between floral diet breadth and canopy openness. We further predicted (2) increased canopy cover would result in less floral richness, and greater niche overlap among bumble bee species. Our results support the first hypothesis for two of our most abundant species but not the third. Moreover, floral richness was indeed lower with greater canopy cover, but responses in niche overlap varied across our three most abundant species. This demonstrates that different bumble bees have varying responses in foraging behavior to forest canopy structure. This research provides information that could assist in conifer forest management practices to better provide for wild bumble bee community restoration and conservation.en-USCreative Commons BY-NC-ND 4.0-USUO theses and dissertations are provided for research and educational purposes and may be under copyright by the author or the author’s heirs. Please contact us <mailto:scholars@uoregon.edu> with any questions or comments. In your email, please be sure to include the URL and title of the specific items of your inquiry.bumble beepopulation declinehabitat losstree canopiesThesis / Dissertation