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Abstract Understanding habitat needs and patch utilization of wild and managed bees has been identified as a national research priority in the United States. We used occupancy models to investigate patterns of bee use across 1030 transects spanning a gradient of floral resource abundance and richness and distance from apiaries in the Prairie Pothole Region (PPR) of the United States. Estimates of transect use by honey bees were nearly 1.0 during our 3.5‐month sampling period, suggesting honey bees were nearly ubiquitous across transects. Wild bees more frequently used transects with higher flower richness and more abundant flowers; however, the effect size of the native flower abundance covariate (β^native = 3.90 ± 0.65 [1SE]) was four times greater than the non‐native flower covariate (β^non‐native = 0.99 ± 0.17). We found some evidence that wild bee use was lower at transects near commercial apiaries, but the effect size was imprecise (β^distance = 1.4 ± 0.81). Honey bees were more frequently detected during sampling events with more non‐native flowers and higher species richness but showed an uncertain relationship with native flower abundance. Of the 4039 honey bee and flower interactions, 85% occurred on non‐native flowers, while only 43% of the 738 wild bee observations occurred on non‐native flowers. Our study suggests wild bees and honey bees routinely use the same resource patches in the PPR but often visit different flowering plants. The greatest potential for resource overlap between honey bees and wild bees appears to be for non‐native flowers in the PPR. Our results are valuable to natural resource managers tasked with supporting habitat for managed and wild pollinators in agroecosystems.

Background Lake Sinai Viruses (LSV) are common RNA viruses of honey bees (Apis mellifera) that frequently reach high abundance but are not linked to overt disease. LSVs are genetically heterogeneous and collectively widespread, but despite frequent detection in surveys, the ecological and geographic factors structuring their distribution in A. mellifera are not understood. Even less is known about their distribution in other species. Better understanding of LSV prevalence and ecology have been hampered by high sequence diversity within the LSV clade. Methods Here we report a new polymerase chain reaction (PCR) assay that is compatible with currently known lineages with minimal primer degeneracy, producing an expected 365 bp amplicon suitable for end-point PCR and metagenetic sequencing. Using the Illumina MiSeq platform, we performed pilot metagenetic assessments of three sample sets, each representing a distinct variable that might structure LSV diversity (geography, tissue, and species). Results The first sample set in our pilot assessment compared cDNA pools from managed A. mellifera hives in California (n = 8) and Maryland (n = 6) that had previously been evaluated for LSV2, confirming that the primers co-amplify divergent lineages in real-world samples. The second sample set included cDNA pools derived from different tissues (thorax vs. abdomen, n = 24 paired samples), collected from managed A. mellifera hives in North Dakota. End-point detection of LSV frequently differed between the two tissue types; LSV metagenetic composition was similar in one pair of sequenced samples but divergent in a second pair. Overall, LSV1 and intermediate lineages were common in these samples whereas variants clustering with LSV2 were rare. The third sample set included cDNA from individual pollinator specimens collected from diverse landscapes in the vicinity of Lincoln, Nebraska. We detected LSV in the bee Halictus ligatus (four of 63 specimens tested, 6.3%) at a similar rate as A. mellifera (nine of 115 specimens, 7.8%), but only one H. ligatus sequencing library yielded sufficient data for compositional analysis. Sequenced samples often contained multiple divergent LSV lineages, including individual specimens. While these studies were exploratory rather than statistically powerful tests of hypotheses, they illustrate the utility of high-throughput sequencing for understanding LSV transmission within and among species.

The lack of seasonally sustained floral resources (i.e. pollen and nectar) is considered a primary global threat to pollinator health. However, the ability to predict the abundance of flowering resources for pollinators based upon climate, weather, and land cover is difficult due to insufficient monitoring over adequate spatial and temporal scales. Here we use spatiotemporally distributed honey bee hive scales that continuously measure hive weights as a standardized method to assess nectar intake. We analyze late summer colony weight gain as the response variable in a random forest regression model to determine the importance of climate, weather, and land cover on honey bee colony productivity. Our random forest model predicted resource acquisition by honey bee colonies with 71% accuracy, highlighting the detrimental effects of warm, wet regions in the Northcentral United States on nectar intake, as well as the detrimental effect of years with high growing degree day accumulation. Our model also predicted that grassy–herbaceous natural land had a positive effect on the summer nectar flow and that large areas of natural grassy–herbaceous land around apiaries can moderate the detrimental effects of warm, wet climates. These patterns characterize multi-scale ecological processes that constrain the quantity and quality of pollinator nutritional resources. That is, broad climate conditions constrain regional floral communities, while land use and weather act to further modify the quantity and quality of pollinator nutritional resources. Observing such broad-scale trends demonstrates the potential for utilizing hive scales to monitor the effects of climate change on landscape-level floral resources for pollinators. The interaction of climate and land use also present an opportunity to manage for climate-resilient landscapes that support pollinators through abundant floral resources under climate change.