Prairie bee community composition along a precipitation gradient in Kansas

Pollinators face many threats today including habitat loss and fragmentation, increased pesticide usage, and new pathogens. Climate change can accentuate these threats through increased temperatures, expanded arid areas, and more frequent and intense extreme weather events. Climate change has made the Great Plains drier overall and is predicted to continue doing so. As Kansas dries, eastern areas of the state will become more climatically similar to western areas, forcing pollinators to move eastward, or face local extinction. Over 400 species of bees have been recorded in Kansas and little is known about the distributions of many of them. To better understand how bee communities vary throughout the state, we sampled 30 prairie sites spread across the precipitation gradient found in Kansas during the summer of 2023. These sites were divided evenly amongst tallgrass, shortgrass, and mixed-grass prairies. Within each prairie type, five sites were grazed and five were ungrazed. Bee communities in mixed and shortgrass prairies were similar, compared to those in tallgrass prairies. Bee abundance was greatest in tallgrass and shortgrass prairies and in prairie dominated landscapes. Grazed sites had greater bee abundance in shortgrass prairies. Halictidae abundance increased with greater short-term precipitation in mixed and shortgrass prairies but decreased in tallgrass prairies. This study aims to establish baseline information on the distribution of bee species in Kansas and to predict how bee communities will change with predicted changes in climate and land use. These results will inform efforts to conserve wild bee populations in Kansas.