Under authority of the Western and Central Pacific Fisheries Convention Implementation Act (16 U.S.C. 6901 et seq.), NMFS proposes to implement fishing effort limits for the U.S. purse seine fishery operating in the western and central Pacific Ocean (WCPO). Regulations at 50 CFR 300.223(a) currently limit U.S. WCPO purse seine fishing effort in a combined area of the high seas and U.S. exclusive economic zone (EEZ). Based on recent decisions of the Commission for the Conservation and Management of Highly Migratory Fish Stocks in the Western and Central Pacific Ocean, this rulemaking would implement separate U.S. WCPO purse seine fishing effort limits for the high seas and U.S. EEZ. This rulemaking could have some economic effects on U.S. purse seine vessels, as the separate effort limits would reduce the operational flexibility provided by the combined effort limits. This rulemaking could also have some economic effects on American Samoa, as the separate limits could lead to a fishery closure earlier in the year than under the combined limits, which could reduce fish supply to the cannery based in American Samoa. Other elements of this rulemaking include modifications to the process for closing the fishery once an effort limit is reached, and modifications to the procedures for obtaining daily purse seine fishing effort reports.