Bee Communities within a Remnant Prairie Site in the Texas High Plains

Declines in native bee populations are thought to be related to increased urbanization, pathogens, insecticides, and a decrease in the availability of native vegetation. Reduced native bee populations can potentially result in impaired pollination of crops and native vegetation, ultimately decreasing landscape biodiversity. Monitoring bee populations and discerning species associations with particular habitat types, vegetation, and weather conditions is critical for understanding how future changes in landscape use and climate may potentially affect native bees. In this study, native bees were surveyed in two ecological sites (“ecosites”), Deep Hardland 16-21" PZ and Sandy Loam 16-21" PZ, on a remnant prairie site located within the city of Lubbock, Texas. We conducted surveys of bee populations, vegetation cover, and floral abundance monthly from early (June) to late summer (September or October) over two years. The number of bees, genera, and species captured along with the number of flowering forb species and the number of individuals with flowers were analyzed using linear mixed models including the effects of year, collection period, ecosite, and their interactions. The relationships between landscape features (e.g., ground cover, floral abundance) and weather and the number of bees caught were analyzed using a correlation analysis. Over two years, 16 genera and 25 species were caught. The most common genera caught were Lasioglossum, Agapostemon, Sphecodes, and Anthophorula. The number of bees captured, floral species, and floral abundance appear to be related to daily weather conditions and prior precipitation. Dominant bee species exhibited positive relationships with cover and/or floral abundance of at least one of the forb species occurring at the collection sites. Bees were generally positively correlated with bare ground and negatively correlated with litter cover. Results can better inform and help predict where and when native bees will be present and provide insight into how native vegetation and other site attributes may be managed to promote populations of native bees.