Endangered Salmon Predation Prevention Act (Sec. 3) This bill amends the Marine Mammal Protection Act of 1972 to authorize the National Oceanic and Atmospheric Administration (NOAA) to issue permits allowing Washington, Oregon, Idaho, the Nez Perce Tribe, the Confederated Tribes of the Umatilla Indian Reservation, the Confederated Tribes of the Warm Springs Reservation of Oregon, and the Confederated Tribes and Bands of the Yakama Nation to kill sea lions in a portion of the Columbia River and certain tributaries in order to protect certain fish from sea lion predation. Specifically, the permits may be issued to protect (1) endangered or threatened species of salmon, steelhead, or eulachon; and (2) species of lamprey or sturgeon that are listed as a species of concern. Permits may be issued to kill sea lions only if the sea lions are part of a population that is not categorized as depleted or strategic. The cumulative annual taking of sea lions each year under all such permits is limited to 10% of the annual potential biological removal level (the maximum number of animals that may be removed from a marine mammal stock while allowing that stock to reach or maintain its optimum sustainable population). In addition, the takings must be humane. NOAA must suspend the issuance of the permits if, after five years, lethal removal authority is no longer necessary to protect fish from sea lion predation. (Sec. 5) The Department of Commerce must study the effectiveness of the permits on the recovery of endangered and threatened salmon and steelhead stocks.