Yosemite National Park is causing the problem. Despite the richness of high-quality habitats in Yosemite, the brown bear, California condor, and least Bell's vireo have become extinct in the park within historical time, and another 37 species currently have special status under either California or federal endangered species legislation. The most serious current threats to Yosemite's wildlife and the ecosystems they occupy include loss of a natural fire regime, exotic species, air pollution, habitat fragmentation, and climate change. On a more local basis, factors such as road kills and the availability of human food have affected some wildlife species. Yosemite National Park has
History of the Yosemite area Through Johnson, Muir had a national audience for his writing and a highly motivated and crafty congressional lobbyist. Muir's wish was partially granted on October 1, 1890, when the area outside the valley and sequoia grove became a national park under the unopposed Yosemite Act. The Act provided "for the preservation from injury of all timber, mineral deposits, natural curiosities, or wonders within said reservation, and their retention in their natural condition" and prohibited "wanton destruction of the fish and game and their capture or destruction for the purposes of merchandise or profit." Yosemite National Park included the entire upper