** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** POLLINATORS SERVE A CRITICAL ROLE IN OUR NATIVE ECOSYSTEMS AS WELL AS AGRICULTURAL CROPS, PROVIDING BILLIONS OF DOLLARS IN POLLINATION SERVICES ANNUALLY. RECENTLY, PARASITES HAVE BEEN LINKED TO DECLINES OF SEVERAL POLLINATOR SPECIES, WITH SPILLOVER OF PARASITES FROM ONE SPECIES TO ANOTHER IDENTIFIED AS A MAJOR CONCERN. THUS, A BETTER UNDERSTANDING OF PARASITE SPILLOVER AMONG BEES HAS IMPORTANT CONSERVATION AND ECONOMIC IMPLICATIONS. OUR PROJECT SEEKS TO UNDERSTAND AND ULTIMATELY CONTROL DISEASE SPILLOVER IN BEE COMMUNITIES. WE WILL COLLECT DETAILED TIME-VARYING EMPIRICAL CONTACT PATTERN DATA FROM PLANT-POLLINATOR NETWORKS AND QUANTIFY TRANSMISSION PARAMETERS FOR DISEASE SPREAD AT FLOWERS AND WITHIN COLONIES OF SOCIAL BEES TO IDENTIFY POTENTIAL TRANSIENT RESERVOIR COMMUNITIES AND/OR SPECIES. THESE DATA WILL BE USED TO PARAMETERIZE DYNAMIC MODELS AND CONDUCT TIME-DEPENDENT SENSITIVITY ANALYSES OF DISEASE SPREAD AND SPILLOVER. MODEL PREDICTIONS WILL THEN BE TESTED VIA WHOLE-COMMUNITY MANIPULATIONS OF BEES, PARASITES AND PLANTS IN MESOCOSMS. THE WORK OUTLINED IN THIS PROPOSAL WILL PROVIDE TANGIBLE INSIGHT INTO FACTORS SHAPING DISEASE SPILLOVER IN BEE COMMUNITIES, WHICH HAS THE POTENTIAL TO IMPROVE MANAGEMENT EFFORTS, SUCH AS GUIDELINES FOR BEEKEEPERS AND COMMERCIAL BEE DISTRIBUTERS, AND THE DESIGN OF POLLINATOR-FRIENDLY WILDFLOWER STRIPS ON STATE AND FEDERAL LANDS.