The Marine Mammal Protection Act (MMPA) prohibits, with certain exceptions, the taking of marine mammals in United States waters, including sea lions and seals (pinnipeds).  Under the MMPA, there are several pathways by which a state may receive approval from National Oceanic and Atmospheric Administration (NOAA) Fisheries Division for the take of protected marine mammals.

Under section 104 of the MMPA, take permits may be granted to states or other entities for incidental takes, scientific research, and for first-time import or capture of wild marine animals for public display.

Under section 109 of the MMPA, NOAA Fisheries may transfer management of a marine mammal to a state.  To receive authority, a state must implement a program for conservation and management of a marine mammal consistent with the goals and policies of the MMPA, requires humane taking of any marine mammals, only permits the taking of marine mammals when a species is at its optimum sustainable population, and meets other specified criteria.

Under section 120 of the MMPA, a state may apply to NOAA Fisheries for the lethal taking of individually identifiable pinnipeds having a negative impact on salmonid fishery stocks, which are listed under the federal Endangered Species Act (ESA), are approaching federal ESA threatened or endangered status, or that migrate through the Ballard Locks in Seattle.  An application must include a description of the problem interaction, expected benefits of the taking, and the means by which the state will identify individual pinnipeds for removal.  NOAA Fisheries may not approve removal of pinnipeds from species or stock listed as threatened or endangered under the ESA, depleted, or identified as a strategic stock.

If NOAA Fisheries determines there is sufficient evidence for a section 120 application to move forward, it must establish a Pinniped-Fishery Interaction Task Force (task force).  The task force must analyze and recommend whether to approve or deny the application, suggest nonlethal alternatives if applicable and a recommended course of action, and, if the application is approved, evaluate the effectiveness of the permitted lethal taking or alternative actions taken.  

Since 2008, Washington, Oregon, and California have received federal approval to remove California sea lions in the vicinity of the Bonneville Dam on the Columbia River.  In December 2018, the United States Congress amended section 120 of the MMPA to create a separate process to authorize the legal take of sea lions in the Columbia River and its tributaries.  This new take authority under the MMPA may address any sea lion, rather than just California sea lions.  In addition, the new authority expands the area in which sea lion take is permitted.

The Department of Fish and Wildlife (DFW) must contract with the Washington State Academy of Sciences to coordinate an independent science panel to review and evaluate the effect of pinniped predation on Chinook salmon in Puget Sound and Washington's outer coast.   DFW must convene a management panel of state, tribal, and federal agencies to communicate with the independent science panel and assess management actions to include in a potential federal take permit application under the MMPA.  The assessment must consider all options available under the MMPA along with how the act may be improved to address the unique challenges in Puget Sound.  DFW must consult with treaty Indian tribes in Puget Sound and the outer coast, recreational and commercial fishers, and conservation organizations, and submit a report of the pinniped predation impacts and the recommendations under the MMPA by December 31, 2022.