This bill amends the Marine Mammal Protection Act of 1972 to grant specific authority to federally recognized Indian Tribes with ancestral ties to the Columbia River. It authorizes these Tribes to intentionally lethally take California sea lions and Steller sea lions (Eastern Distinct Population Segment) within a defined portion of the Columbia River's mainstem and tributaries, specifically from River Mile 0 to the McNary Dam in Washington and Oregon. This measure is intended to address the impact of these pinniped populations on salmon. The authorization allows for the take of an unlimited number of these marine mammals at any time, without requiring individual identification, provided the Tribe determines the methods used are humane and appropriate. Tribes are also permitted to designate other individuals to carry out these actions on their behalf. Importantly, the bill clarifies that this new authority does not diminish any existing Tribal rights or authorities under treaties or other laws.