SEATTLE — Seattle Mayor Jenny Durkan filed a letter of protest Wednesday on behalf of the city of Seattle, slamming proposed testing and training by the U.S. Navy that could harm endangered southern resident killer whales and other marine mammals in Puget Sound.

Durkan filed the letter as a public comment on the Navy’s draft environmental-impact statement (EIS) on its testing program.

The environmental-impact documents outline the Navy’s preferred plan for testing and training — including the use of sonar and explosives — beginning next year in Puget Sound, coastal waters from northern California through Washington state and for Alaska.

In her letter, the mayor asked the Navy to incorporate greater protections for the southern residents, including use of real-time whale-presence alert systems. She also asked the Navy to adjust the time of year for testing and training activities to limit impact on orca habitat.

In addition to her public comment submitted to the Navy in response to the draft EIS, she also transmitted a resolution to the Seattle City Council calling for the Navy to forego all training and testing activities when southern resident orcas, humpbacks and other marine animals are present.

In its modeling of effects of its testing and training program on marine mammals, the Navy predicts the southern residents would exhibit behavioral responses about 15 times over seven years. The documents say endangered humpback whales in waters off California, Oregon and Washington would suffer temporary hearing loss 277 times and alter their behavior 221 times because of sonar.

Sean Hughes, Navy Region Northwest Public Affairs Officer, said the Navy will consider the letter and all other substantive comments on its testing program as part of its work on the final EIS.

“The Navy highly values the comments received from government leaders, American Indian Tribes and citizens of every background as an important part of our decision-making process,” he said. “The Navy takes its obligations to the environment seriously, as we do our obligations concerning national security.”

The Navy previously has acknowledged damaging effects of sonar and underwater explosions on whales, including disorientation and fleeing feeding grounds.

However, the Navy also has several representatives on the Gov. Jay Inslee’s Southern Resident Killer Whale Task Force, “and is proud to be a part of the collective effort supporting the recovery of the species,” Hughes said. “We have also been a key contributor to marine species monitoring projects for a number of years to advance scientific knowledge of Southern Resident Killer Whales and the salmon that they so rely on.”

Durkan said Seattle has a key role to play as the testing-program deliberations continue.

“The City of Seattle offers a unique voice on this issue, as we are the largest United States city within the critical habitat of southern resident orcas,” Durkan wrote in her letter to the Navy.

“These (testing) activities will impact our marine mammals, especially orcas, who rely upon echolocation for hunting and navigation and sound to communicate within and between pods.”

Vessel noise and disturbance is one of three main threats to southern resident orca survival, in addition to lack of adequate available food, especially chinook salmon, and toxins in the environment.