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The current status and distributional uncertainties of some Bombus (bumble bee) species across North America has driven the need for monitoring. The central Appalachian Mountain region has historic and recent records of the endangered Bombus affinis (Rusty Patched Bumble Bee), but the species' distribution within the region is unknown. To address the lack of knowledge on distribution of bumble bee species within the region, specifically Rusty Patched Bumble Bee, I randomly generated a network of 70 roadside transects and conducted 764 ten-minute non-lethal surveys. These surveys recorded 11 out of 14 species, including Rusty Patched Bumble Bee, thereby validating that 10-minute surveys using nonlethal techniques at randomly generated roadside locations can document the bumble bee community of the region. [ABSTRACT FROM AUTHOR]

Declines in bumble bee species range and abundances are documented across multiple continents and have prompted the need for research to aid species recovery and conservation. The rusty patched bumble bee (Bombus affinis) is the first federally listed bumble bee species in North America. We conducted a range-wide population genetics study of B. affinis from across all extant conservation units to inform conservation efforts. To understand the species' vulnerability and help establish recovery targets, we examined population structure, patterns of genetic diversity, and population differentiation. Additionally, we conducted a site-level analysis of colony abundance to inform prioritizing areas for conservation, translocation, and other recovery actions. We find substantial evidence of population structuring along an east-to-west gradient. Putative populations show evidence of isolation by distance, high inbreeding coefficients, and a range-wide male diploidy rate of ~15%. Our results suggest the Appalachians represent a genetically distinct cluster with high levels of private alleles and substantial differentiation from the rest of the extant range. Site-level analyses suggest low colony abundance estimates for B. affinis compared to similar datasets of stable, co-occurring species. These results lend genetic support to trends from observational studies, suggesting that B. affinis has undergone a recent decline and exhibit substantial spatial structure. The low colony abundances observed here suggest caution in overinterpreting the stability of populations even where B. affinis is reliably detected interannually. These results help delineate informed management units, provide context for the potential risks of translocation programs, and help set clear recovery targets for this and other threatened bumble bee species. [ABSTRACT FROM AUTHOR]