THE OVERALL GOAL OF THE PROJECT IS TO MAKE SIGNIFICANT HARDWARE ADVANCEMENTS TO THE AERODYNAMIC-WHISTLE-BASED ULTRASONIC DETERRENTS DEVELOPED AT IOWA STATE AND TO DEMONSTRATE THEIR ULTRASOUND-GENERATION CAPABILITY ON A UTILITY-SCALE WIND TURBINE IN FIELD. THE SPECIFIC OBJECTIVES ARE: 1. DEVELOP OPTIMAL ACTIVE AND PASSIVE DETERRENT DESIGNS. DEMONSTRATE ACOUSTIC PERFORMANCE OF THE ACTIVE WHISTLES, INCLUDING AMPLITUDE AND FREQUENCY MODULATION. 2. DEMONSTRATE THE ACOUSTIC PERFORMANCE OF THE PASSIVE DETERRENT MOUNTED ON A BLADE SECTION. 3. DEMONSTRATE THAT THE PASSIVE DETERRENT HAS AN INSIGNIFICANT IMPACT ON THE AERODYNAMIC PERFORMANCE OF THE TURBINE. INVESTIGATE VARIATION WITH FLOW SPEED AND ANGLE OF ATTACK TO COVER THE OPERATING PARAMETER SPACE. 4. FIELD DEMONSTRATION OF THE ACTIVE AND PASSIVE ISU DETERRENTS MOUNTED ON TURBINE BLADES AND NACELLE, RESPECTIVELY.