Underwater Sound Levels in Glacier Bay During Reduced Vessel Traffic Due to the COVID-19 Pandemic

Underwater sound levels in Glacier Bay National Park, USA, dropped significantly during the COVID-19 pandemic due to reduced vessel traffic. Analysis of hydrophone recordings revealed that broadband sound levels were 2.7 dB lower in 2020 compared to previous years (2018 and 2016), with even greater reductions (3.3–5.1 dB) observed during peak tour vessel and cruise ship activity times. The 95th percentile of loudest sounds was 6.3–9.0 dB quieter in 2020, indicating the combined acoustic impact of all vessel types. A notable 3 dB decline in the 125 Hz band suggests changes in medium and large vessel noise or harbor seal vocalizations. This study highlights the substantial influence of vessel traffic on underwater soundscapes and provides insights for mitigating noise impacts in marine protected areas.

Gabriele, C. M., Ponirakis, D. W., & Klinck, H. (2021). Underwater Sound Levels in Glacier Bay During Reduced Vessel Traffic Due to the COVID-19 Pandemic. Frontiers in Marine Science, 8. https://doi.org/10.3389/fmars.2021.674787