This record represents encounters of mid-frequency active sonar. Encounters of mid-frequency active sonar were logged manually from Long-term Spectral Averages using the Logger remora in Triton and user-defined settings. All detected signals with the same characteristics detected within 1 hour of each other were considered one encounter.These data were recorded at SanctSound Site HI04_02 between December 01, 2019 and May 11, 2020.