Wild bee microbiomes and pollinator health
The holobiont view of organism microbiomes suggests that microbial communities influence and are influenced by animal behaviour. While many microbes are beneficial and necessary for digestion and homeostasis, others can be detrimental, including pathogens leading to compromised immunity and disease states. Recent studies suggest microbiomes covary with landscape floral and fungal diversity, yet fine scale data does not exist examining consistent hubs for beneficial and pathogenic microbes outside of select few crop and flower species. There is evidence that floral diversity promotes healthy microbiomes, but this research has largely focused on mammals and there is surprisingly no data on wild bees in urban systems. Bees are a keystone group responsible for pollinating most wild plants. Yet populations of many wild bees are declining and to ensure sustainable pollination, their conservation is essential. As cities are often hotspots for bee diversity, they may be crucial reservoirs for the maintenance of bee diversity, and particularly so when cities are surrounded by forests or croplands that are less favourable for bees. It is known that habitat heterogeneity is an important correlate of bee diversity, and urban centres, where land management practices vary harbour diverse wild bee assemblages. We will combine state-of-the-art metagenomics document wild bee microbiomes and nutritional ecology for the first time to provide conservation guidelines to promote the sustainability of populations of the major wild pollinators in urban centres. Our findings will be relevant to the >80% of Canadians that are urban dwellers.