We, the National Marine Fisheries Service (NMFS), establish regulations under the Endangered Species Act (ESA) and Marine Mammal Protection Act (MMPA) to prohibit vessels from approaching killer whales within 200 yards (182.9 m) and from parking in the path of whales when in inland waters of Washington State. Certain vessels are exempt from the prohibitions. The purpose of this final rule is to protect killer whales from interference and noise associated with vessels. We identified disturbance and sound associated with vessels as a potential contributing factor in the recent decline of this population during the development of the final rule announcing the endangered listing of Southern Resident killer whales and the associated Recovery Plan for Southern Resident killer whales (Recovery Plan). The Recovery Plan calls for evaluating current guidelines and assessing the need for regulations and/or protected areas. To implement the actions in the Recovery Plan, we developed this final rule after considering comments submitted in response to an Advance Notice of Proposed Rulemaking (ANPR) and proposed rule, and preparing an environmental assessment (EA). This final rule does not include a seasonal no-go zone for vessels along the west side of San Juan Island that was in the proposed rule. We will continue to collect information on a no-go zone for consideration in a future rulemaking.