Defense Presentation Title: Fields and Foragers: Linking Pesticide Landscapes to Wildlife Demography for Pollinator Risk Assessments

Co-Advisors: Dr. Tom Purucker, US Environmental Protection Agency; Dr. Helena Mitasova, Associate Director of Earth and Environmental Sciences Applications

Abstract: Invertebrate pollinators are exposed to pesticides during and after chemical applications in agricultural landscapes; these exposures can have wide-ranging consequences including loss of pollination services that may impact ecological and economical resources. The landscape of spatiotemporal data available to assess ecological risk is limited due to a lack of information on specific application extents and exposure scenarios (i.e., identification of the duration, frequency and timing of exposure routes along with measurable chemical residues), and their connections to quantifiable population-level impacts in a spatial framework. This work addresses these research gaps across a decreasing spatial extent in the Midwestern United States. We first develop an approach to capture the distribution of agricultural fields that can be used to better quantify pesticide use patterns at regional scales. This work is coupled with a methodology for simulating spatiotemporally explicit pesticide residues that is compared against empirical data. Finally, we evaluate the potential mechanistic impacts of these exposures for an endangered bumblebee species, Bombus affinis, by simulating foundress queen survival under simulated foraging scenarios. Together, outcomes from this work can provide valuable information for decision support and ecological risk assessments for pollinators.