WHIDBEY ISLAND — A battle continues over jets at Naval Air Station Whidbey Island, with the most recent fight being over how the noise generated by a growing number of EA-18G Growler jets stationed at the military base impacts wildlife.
Based on research published in November, the nonprofit Citizens of Ebey’s Reserve, or COER, is threatening to sue the Navy, as well as NOAA Fisheries and the U.S. Fish and Wildlife Service, if the federal agencies don’t reconsider how Growler flights may impact endangered southern resident orcas and threatened marbled murrelets.
The threat of legal action is based on two studies, each published in peer-reviewed journals.
NAS Whidbey Island Public Affairs Officer Mike Welding said the Navy disagrees with some of the scientific methodologies and conclusions made in the studies.
One study focused on the noise level on the Olympic Peninsula during practice flights over the area.
The other included placing a hydrophone about 30 meters — roughly 98 feet — beneath the water near the Ault Field runway of the base. That study documented underwater noise during Growler jet flights at levels known to trigger behavioral changes in fish, birds and marine mammals.
The hydrophone collected underwater data over 28 days from mid-August to mid-September in 2019, according to the published report. The researchers looked for noise levels that could have an impact on wildlife including whale, seal and bird species.
“Our goal was to evaluate potential impacts on people and wildlife, using thresholds of response that have been established in previous studies,” the study states.
Lauren Kuehne, an environmental scientist involved in both studies, said during an event Tuesday hosted by Western Washington University’s Salish Sea Institute that underwater noise from aircraft has historically been “ignored based on the assumption that most of it reflects off of the water.”
Other speakers, including conservation scientists and public-health experts, agreed. They said the hydrophone findings, while limited in scope, offer a critical piece of information.
“It’s audible. The energy … crosses that seemingly impermeable air-water interface, and enough energy propagates that it is audible to multiple species,” marine biologist Rob Williams said.
Todd Hass, of the Puget Sound Partnership, was involved with the state’s Orca Recovery Task Force that convened in 2018 and 2019, and said the findings are concerning for whales.
“We now have a definitive answer to the question: Can that noise penetrate the water to depths that might be heard by southern residents?” he said.
Welding said Navy officials do not believe data from the hydrophone study — collected over short durations of localized noise during take-offs — demonstrates that Growler flights significantly affect orcas. The Navy also contends the orcas seldom visit waters near the runway.
Kuehne, the lead author of the study, has said repeatedly that the research was a small step toward understanding the scope of the issue.
“This study was very much a first cut at thinking about and evaluating the underwater noise,” she told the Skagit Valley Herald.
In COER’s Feb. 9 letter giving a 60-day notice of its intent to sue, the nonprofit argues that the “new scientific information relating to the depth to which Growler aircraft noise penetrates into the water column” requires the Navy and federal agencies responsible for protecting at-risk wildlife to reassess NAS Whidbey operations under the Endangered Species Act.
Welding and Michael Milstein of NOAA Fisheries — the federal agency responsible for upholding Endangered Species Act protections of marine wildlife — said their agencies would not comment on pending or potential litigation.
Salish Sea Institute Director Ginny Broadhurst said the Navy declined to join Tuesday’s event.
An email from Welding to the event organizers said Navy participation could be problematic due to ongoing litigation and the recent threat of an additional lawsuit from COER.
Jet noise has been a subject of disagreement for years, with some residents of Whidbey Island and surrounding areas saying that noise from practice flights over homes, schools, parks and waters interrupts daily life and threatens the environment.
The Navy base is an important location for jets that may board military aircraft carriers and engage in electronic warfare. The pilots of those jets need ongoing practice for taking off and landing on those ships.
The Navy is in the midst of a land-based jet noise monitoring study requested by Congress.
The project began collecting real-time noise monitoring over a seven-day period in December.
Welding said the monitoring sites are across Whidbey Island, Lopez Island, Port Townsend and Olympic National Park, and data will be collected during three more seven-day periods before the end of 2021.
The study that recently probed underwater jet noise was led by researchers from the University of Washington’s School of Aquatic and Fishery Sciences, in collaboration with a consulting group, an Australian university and the nonprofit Oceans Initiative.