The Alaska Native Claims Settlement Act of 1971 (ANCSA), an outgrowth of the Alaska Statehood Act, is a law of enormous importance to the National Wildlife Refuge System. Among numerous other provisions, it authorized the addition of immense areas of highly productive, internationally significant wildlife lands to the NWRS. Further far-reaching resource protection measures for Alaska were mandated by Congress in the passage on December 2, 1980, of the Alaska National Interest Lands Conservation Act (ANILCA). The Act added nine new refuges, expanded seven existing refuges and added 53.7 million acres (217,000 km²) to the NWRS. This Act alone nearly tripled the area of lands encompassed in the Refuge System.