Buoy will monitor underwater noise in hopes of quieting Puget Sound for endangered orcas
Underwater noise is one of the threats to Puget Sound’s endangered southern resident killer whales. King County has just deployed a new tool in the efforts to address that.
During a livestreamed event, researchers on board King County’s environmental research vessel, Sound Guardian, lowered a special buoy into Puget Sound. It’s about a mile offshore, north of Seattle, in an area where the southern residents are often seen following chum salmon runs at this time of year.
Armed with hydrophones and software, the buoy will monitor the underwater soundscape and scan for the presence of orcas while it measures and records levels of underwater noise. It will then share the data through a cellular transmitter.
“We're hoping that this kind of live feed data might help with some of the efforts in Puget Sound,” said Dr. Jason Wood, standing on deck after the buoy was lowered into the sound.
His company, SMRU Consulting, developed the technology and is doing this study pro bono, with the aim of using the data to alert the pilots of large vessels nearby. The noise from their engines can prevent orcas from finding increasingly scarce salmon in the whales’ customary feeding areas. But slowing down reduces the impact considerably. Wood says they could also opt to switch directions. And it can be used to make decisions about the timing of underwater construction projects, to avoid disturbing the southern residents.
“We've been working for years now with the ECHO program of the Vancouver Fraser Port Authority in Canada, and they've been doing voluntary slowdowns of Haro (Strait) and Boundary Pass since 2017,” he said.
Canada’s ECHO program is voluntary, yet has a compliance rate of 80 to 90 percent.
King County is supporting the mission by providing the use of Sound Guardian. Crewmember Bob Kruger says it’s an exciting addition to the work they do every week testing the water for chemicals and sampling for plankton and other small organisms.
“So to be able to use some other equipment that actually looks at the megafauna, versus all the micro stuff we're looking at, is really exciting for our crew. And we love helping these guys out beause they're doing great work,” Kruger said.
The buoy will be in place for about three months. It will support the goals of Washington’s Quiet Sound program, which will be similar to Canada’s ECHO, but is just now beginning to get off the ground. Quiet Sound was created by the governor’s orca task force in 2018.