Communities within communities: Investigating the biodiversity of prairie pollinators and their endosymbionts

Pollinators are suffering declines worldwide due to native habitat loss, pesticide use, and global climate change. North Dakota is one of the most pollinator dependent states for agricultural crops; little is known about the composition of the pollinator community and their overall health. Environmental and land management practices in the region impact both the insect and its microbiome, a community of gut bacteria that maintain pollinator health. Much is known about the microbiomes of commercial pollinators, such as the honey bee, but less is known about the microbiome of native pollinators (bees and flies), which are crucial to natural habitats. Gut microbial diversity is central to pollinator health, and microbes spread between species of pollinators through the flowers that they pollinate. Microbes found in flowers and their nectar, which attracts insects, may impact the microbial diversity of pollinators. We seek to understand how these microbes spread through pollinator communities by identifying pollinators, plants and symbionts found in insects and plants. During the last three summers (2021-2023), we collected plants, native and feral-commercial bees, and flies to address microbial sharing between community members. Using DNA identification and Next Generation Sequencing Approaches, we identified pollinator and bacterial species in these samples. We documented shared microbes for both hymenopteran and dipteran pollinators and examine if these microbes are found on plants where these insects were collected. We also confirm host plants by identifying pollen within insect digestive systems. This work represents first steps for understanding pollinator communities in the Northern Great Plains.