THIS PROJECT WILL USE FATALITY AND BEHAVIORAL METRICS TO EVALUATE THE REDUCTION OF BAT FATALITIES AT WIND TURBINES USING AIRCRAFT LIGHTING DETECTION SYSTEMS (ADLS). THESE METRICS WILL ALLOW US TO UNDERSTAND THE REAL-WORLD EFFICACY AND IMPACT REDUCTION POTENTIAL OF ADLS AS A PASSIVE DETERRENT AT MULTIPLE COMMERCIAL-SCALE WIND ENERGY FACILITIES ACROSS SPACE AND TIME IN AN EFFORT TO LEAD TO STAKEHOLDER ACCEPTANCE OF ADLS AS A BAT FATALITY MINIMIZATION TOOL. SPECIFICALLY, OUR OBJECTIVES ARE TO: 1. DETERMINE FATALITY RATES OBSERVED AT FACILITIES WITH AND WITHOUT ADLS INSTALLED. WE WILL USE POST-CONSTRUCTION MONITORING (PCM) DATA FROM THE RENEW AND AMERICAN WIND WILDLIFE INFORMATION CENTER (AWWIC) DATABASES TO DESCRIBE FATALITY RATES AT WIND ENERGY FACILITIES WITH ADLS INSTALLED AND AN EQUAL NUMBER OF NEARBY FACILITIES WITHOUT ADLS. BY USING EXISTING PCM DATA, WE WILL MEASURE THE EFFECTIVENESS OF ADLS ACROSS YEARS AND SITES IN A COST-EFFECTIVE MANNER. 2. QUANTIFY THE FATALITY RISK REDUCTION ASSOCIATED WITH ADLS USE AT WIND ENERGY FACILITIES. WE WILL COMBINE RADAR ACTIVITY RATES AND BAT ACOUSTIC EXPOSURE ACROSS A LANDSCAPE WITH FACILITIES UTILIZING AND NOT UTILIZING ADLS TO DETERMINE THE RISK REDUCTION ASSOCIATED WITH THE USE OF ADLS. 3. EVALUATE THE ATTRACTION OF NOCTURNAL BAT-LIKE OBJECTS TO AVIATION LIGHTING AT TWO WIND FACILITIES IN TWO LATE-SUMMER PERIODS WHEN FATALITIES ARE HIGHEST. WE WILL USE MULTIPLE RADAR SYSTEMS AND BAT ACOUSTIC SAMPLING AT A PAIR OF ADJACENT WIND FACILITIES EQUIPPED WITH AND WITHOUT OPERATIONAL ADLS SYSTEMS TO MEASURE ATTRACTION TO AVIATION LIGHTING USING ABUNDANCE AND TRAJECTORY OF BAT-LIKE OBJECTS AT A LANDSCAPE SCALE.