Hopper Mountain National Wildlife Refuge in the Topatopa Mountains of Ventura County, southern California, was established in 1974 to protect the endangered California condor, its habitat, and other wildlife resources. Covering 2,471 acres beside Los Padres National Forest, it forms part of a major condor stronghold and remains important to the California Condor Recovery Program by providing foraging and roosting habitat. The refuge also supports education about condor recovery. Its rugged landscape includes grasslands, oak and California black walnut groves, chaparral, springs, riparian areas, and a freshwater marsh, sustaining more than 200 plant species and over 130 species of birds, mammals, and reptiles.