The cougar does occur on Mount Diablo, but is rarely seen. Cougars require such a large range that there may be only one or two cats in the area. Cougars eat mainly deer, but will occasionally take smaller prey or carrion. This shy cat is widespread on Mount Diablo, but is rarely seen by park visitors. Residents of the park often see bobcats in the early morning or evening.
Bobcats eat rodents, rabbits, birds, and an occasional deer.
The grey fox is widespread and abundant on Mount Diablo. Foxes are often seen along park roads at night by park residents. Foxes eat rodents, insects and berries. Coyotes are abundant on Mount Diablo, but are rarely seen. Campers and park residents often hear them at night.