Regional 2022 Ocean Noise Contributors in Southern Resident Killer Whale Habitat
November 2024 — Canada
Client: Transport Canada
This study uses an advanced soundscape model to investigate how different marine sectors contributed to underwater noise in Southern Resident killer whale (SRKW) habitat during 2022. Key outputs of the model are maps of sound pressure level (SPL) generated by various vessel types and wind-driven ambient noise for the Salish Sea and Swiftsure Bank. Key inputs to the model include ship tracking data from the Automatic Identification System (AIS) and an extensive database of high-quality measurements of vessel underwater radiated noise. Soundscape maps are broken down into 15 vessel categories and 9 geographic sub-regions to calculate the contributions of different marine transportation sectors to the underwater sound energy budget. The soundscape model is also used to calculate natural ambient noise originating from wind and rain. The difference between ship-generated SPL and natural ambient SPL is used to assess how shipping activity contributes to acoustic masking within sensitive habitat areas.
