President George H. W. Bush signed the Everglades National Park Protection and Expansion Act on December 13, 1989, that added 109506 acres to the eastern side of the park, closed the park to airboats, directed the Department of the Army to restore water to improve the ecosystems within Everglades National Park, and "Direct(ed) the Secretary of the Interior to manage the Park in order to maintain the natural abundance, diversity, and ecological integrity of native plants and animals, as well as the behavior of native animals, as part of their ecosystem."