Tag, you're it! Tracking pollinators on the prairie with radio telemetry

Precipitous declines in pollinator species richness and abundance the past 20 years are primarily attributed to habitat loss, decreased floral resources, pesticide use, disease, and global climate change. The negative impact of these threats to pollinator persistence are synergistic in nature, with the joint impact of habitat loss and decreased floral resources thought to be particularly important in grassland ecosystems. However, detailed population-level studies are lacking for most native pollinator species, and the effects these threats have on pollinator persistence are poorly understood. This knowledge gap makes it difficult to implement effective conservation practices on working landscapes because resource-use data for individual species are needed to inform practices. In grasslands, pollinators evolved with a shifting mosaic of vegetative habitat patches across the landscape, yet traditional rangeland management practices select for uniformity in vegetative habitat structure and plant species composition, thus selecting against many pollinator species. Patch-burn grazing is a conservation practice that selects for habitat heterogeneity on rangelands. This study investigates the resource-use of bumblebee queens using radio telemetry in both traditionally and patch-burn grazing managed cattle pastures. Results indicate tagged queens nested exclusively in one patch-burn grazing patch-type, with all nests within 100meters of the patch edge. Conversely, queens foraged 70% of the time in a second patch-type and 27% in a third patch-type. These findings indicate patch-burn grazing has significant potential to conserve and restore one of North America’s most threatened taxonomic groups of wildlife, grassland bumblebees, with one of it’s most dominant land-use management practices, cattle grazing.