Pollinators are declining globally, threatening global crop production and the biological integrity of many ecosystems. Hymenoptera (the order containing ants, bees, and wasps) is one of the most important insect orders for pollination of a variety of plants, including many crops, and is important as biocontrol for crop pests, and other herbivorous insects. Land management practices affect plant community composition, which influences vegetation-dependent insects, and consequently affects their ecosystem services. Fire and grazing are common practices on working landscapes in the Great Plains. However, how these management techniques impact insect diversity, particularly Hymenopterans, in a mixed-grass prairie ecosystem, is poorly understood. The objective of this study was to better understand how grazing practices affect Hymenopteran diversity. Sweep-net samples of insects were collected from three treatment sites on the mixed-grass prairie including wildfire paired with grazing (WF), winter-patch grazing (WPG), and season-long continuous grazing (CG, as a control). These samples were collected over two years, and each plot was sampled twice during each sampling year (totaling four sampling events). Specimens were then identified to family to better explain how land management practices affect diversity. Each treatment was statistically analyzed using single-factor ANOVA for abundance, family richness, evenness, and the Shannon-Wiener diversity index. Ultimately, this study found that two- and three- years after the initial treatment, there were no differences in Hymenopteran abundance or diversity between pastures treated with WPG, or WF when compared to a CG control.
South Dakota State University
Copyright © 2023 Kaitlin Schieuer
Schieuer, Kaitlin, "Analyzing the Effects of Winter-patch Grazing and Wildfire on Insect Order Hymenoptera in the Northern Great Plains" (2023). Schultz-Werth Award Papers. 39.