**AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** SEVERAL BENEFITS ARE ASSOCIATED WITH LARGE-SCALE ADOPTION OF TRANSGENIC CROPS EXPRESSING INSECTICIDAL PROTEINS FROM THE BACTERIA BACILLUS THURINGIENSIS, COMMONLY REFERRED TO AS BT CROPS. HOWEVER, HELICOVERPA ZEA IS RESISTANT TO SEVERAL BT TRAITS IN CORN AND COTTON, AND VIP IS THE ONLY EFFECTIVE BT TRAIT CURRENTLY COMMERCIALLY PLANTED. HELICOVERPA ZEA IS AN ECONOMIC PEST IN COTTON, AND SIMILAR BT TOXINS ARE EXPRESSED IN CORN AND COTTON. HENCE, THERE IS A HIGH RISK OF H. ZEA EVOLVING RESISTANCE TO VIP-EXPRESSING CROPS ON A BROAD SCALE IN THE CONTINENTAL U.S. IN 2018, THE FINAL EPA FIFRA SAP REPORT CONCLUDED THE REQUIREMENT OF NON-BT REFUGE AS ONE OF THE CORNERSTONES OF BT IRM. HOWEVER, THE ASSUMPTION OF RANDOM MATING BETWEEN REFUGE AND BT CROPS IN THIS SPECIES REMAINS UNTESTED. THE OVERALL GOAL OF THIS PROPOSAL IS TO PROVIDE KNOWLEDGE OF SHORT DISTANCE DISPERSAL CAPACITY AND REPRODUCTIVE POTENTIAL OF H. ZEA, USING MARK-RECAPTURE EGG ALBUMIN MARKER, FLIGHT MILLS, AND ESTIMATION OF THE SEX, MOTH AGE, FEMALE MATING STATUS AND MATURITY, AND STABLE CARBON ISOTOPE SIGNATURE OF WINGS AND SPERMATOPHORES OF FIELD POPULATIONS H. ZEA. THE DATA GENERATED IN THIS PROPOSAL WILL BE USED TO REFINE A DETERMINISTIC, FREQUENCY-BASED MODEL OF H. ZEA POPULATION GENETICS, EXPLORING THE RISK ASSESSMENT NULL HYPOTHESIS THAT MOVEMENT AND REPRODUCTIVE PARAMETERS (DISPERSAL DISTANCE, MATING STATUS, FEMALE MATURITY, AND MOTH AGE AND ORIGIN) WILL NOT IMPACT THE RATE OF RESISTANCE EVOLUTION IN H. ZEA. THIS PROPOSAL WILL SUPPORT ACCURATE IRM REGULATIONS CONCERNING REFUGE FOR THE DEPLOYMENT AND SUSTAINABILITY OF BT CROPS.