SEATTLE (AP) – A new federal lawsuit seeks to establish a “protection zone” for endangered orcas in the Pacific Northwest.

The Center for Biological Diversity and the Orca Relief Citizens’ Alliance sued NOAA Fisheries in U.S. District Court in Seattle, saying the agency has failed to act on a petition it filed in 2016.

The petition sought to bar vessels from a 10- to 12-square-mile (26- to 31-square-kilometer) area west San Juan Island where the orcas feed from April through September each year. Canada has already announced that no vessel traffic will be allowed from June through October in three sanctuary zones in prime orca feeding habitat.

Advocates say vessel noise interferes with the echolocation the orcas use to hunt. The whales are struggling with a dearth of their preferred prey, Chinook salmon.