Seattle – Quiet Sound, a collaborative program from Washington Maritime Blue dedicated to fostering a more sustainable environment for Southern Resident killer whales (SRKW) through reduction in underwater noise pollution announced the official launch of its voluntary vessel slowdown season beginning October 7 through early 2025.
The effort protects the remaining 75 Southern Resident killer whales in the Salish Sea. The start of the commercial vessel showdown was triggered as Southern Resident killer whales were reported in the waters off of Seattle on the morning of October 5. The slowdown period remains in effect through January 12, 2025, key months for their migration.
Container vessels, vehicle carriers, and cruise ships are asked to voluntarily slow to 14.5 knots speed through water, while general cargo, tankers and bulkers are asked to slow to 11 knots in an area 22 nautical miles long through Admiralty Inlet and north Puget Sound. This season’s slowdown also includes a trial speed target for tugs running lite (not towing or pushing) at 10 knots.
“We know that underwater noise from large vessels is one of the major factors threatening the recovery of the endangered Southern Resident killer whales. Last season, we saw the highest participation yet, which reduced underwater noise pollution by 50%.” said Rachel Aronson, Quiet Sound Program Director. “We’re grateful for the enthusiastic participation of our maritime partners, and we hope to have an even bigger positive impact this season.”
The results of the 2023-2024 voluntary vessel slowdown include:
- 71% of 795 vessels passing through the slowdown area decreased their speed.
- 59% of the transits achieved the proposed speed targets.
- Median broadband sound levels were reduced by 3.0 dB, a 50% reduction in sound intensity.
- Southern Resident killer whales were present in the slowdown area for 20 days of the 92- day slowdown (22%).
This 2024-2025 Slowdown will be monitored using a system of hydrophones, data from mariners and AIS, and whale reporting from Orca Network, with a participation goal of more than 80% this season.
Quiet Sound received a Maritime Sustainable Century Award from the Port of Seattle in 2024 for their work in environmental education and outreach. Quiet Sound recently received the North American Marine Environmental Protection Agency (NAMEPA) Non-profit award for 2023 and NOAA’s 2023 Partner in the Spotlight Award for its work to protect the Southern Resident killer whales.
(Photo of orca in Salish Sea from David Suzuki Foundation)
