Center for Whale Research via AP
A female orca, or killer whale, travels with her offspring in waters around the San Juan Islands in Washington State.
Environmental groups sued the Obama administration on Thursday for granting the Navy permits to test underwater sonar along the West Coast -- and potentially harass up to 650,000 porpoises, seals, dolphins and whales over a five-year period.
The alliance said it wasn't seeking to stop the testing but to scale it back, especially at certain times and in waters important for feeding and giving birth.
Several studies have found that marine mammals can hear low-frequency sonar, which is magnified under water, and periodically dolphins and even whales have been found with perforated ear drums.
The National Marine Fisheries Service "fell down on the job and failed to require the Navy to take reasonable and effective actions to protect" marine mammals, Steve Mashuda, an attorney for the law firm Earthjustice, said in a statement.