 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 . 
