Bees and other pollinators serve a critical function in many ecosystems, and their role in pollinating crops is valued at billions of dollars annually. Declines in pollinators have recently been linked to parasites such as the unicellular Crithidia bombi. Pollinators defecate on flowers, and when other pollinators visit the same flower, they can ingest C. bombi and become infected. If environmental and epidemiological factors align—if, for example, plants that attract multiple species of pollinators bloom when parasite infection rates are high in a prevalent pollinator species—parasites may transfer from one species to another, in a phenomenon termed spillover.

Scott H. McArt, Entomology, is leading a cross-college, multi-institutional team of theoreticians, modelers, engineers, and ecologists to understand the temporal and spatial factors shaping parasite spillover in pollinator communities. Over the course of a season, researchers will collect detailed data from plant-pollinator networks and quantify parameters for disease spread. They will then formulate control measures and test the efficacy of those measures by adjusting populations of bees and plants in carefully managed research plots.

This project studies context-dependent temporal dynamics that influence parasite spillover in bee communities. It will generate predictive models that could improve guidelines for beekeepers and commercial bee distributers and could inform the design of pollinator-friendly wildflower strips on state and federal lands. It may also advance our understanding of context-dependent temporal dynamics involved in the spread of disease from animals to humans. Collaborators include Quinn S. McFrederick, University of California, Riverside; Rebecca E. Irwin, North Carolina State University; and Lynn S. Adler, University of Massachusetts, Amherst.

NIFA Award Number: 2021-67015-35235