The mountain lion, known by a variety of regional common names including cougar, puma, and catamount, is a large, solitary predator native to the Americas. This wide-ranging carnivore is the most broadly distributed terrestrial mammal in the Western Hemisphere, spanning from the Yukon in Canada down to the southern Andes mountains. Across the United States, the species’ distribution is not uniform, with its presence defined by distinct populations that are either stable and breeding or temporary and transient. Understanding the current geographic spread of the mountain lion requires distinguishing between these established populations and the occasional sightings that occur far outside their primary range.
States with Established Breeding Populations
The vast majority of mountain lions in the United States reside in a cluster of Western states where populations are considered stable and self-sustaining. These core areas include Washington, Oregon, California, Nevada, Utah, Arizona, New Mexico, Montana, Idaho, Wyoming, and Colorado. California has one of the largest populations, estimated between 4,000 and 6,000 individuals. Colorado also hosts a significant population, ranging from 3,000 to 7,000, supported by extensive mountainous terrain and large elk populations.
Two states outside this main Western block also contain confirmed breeding populations: Texas and South Dakota. In Texas, the population is concentrated primarily in the rugged western and southern regions. South Dakota is home to a smaller but established group, notably in the Black Hills area.
The only confirmed breeding population east of the Mississippi River is the critically endangered Florida panther, a distinct subspecies. This isolated group is confined to the swamplands and forests of South Florida, including Everglades National Park and Big Cypress National Preserve. The population is extremely small, estimated at only 120 to 230 individuals, and is listed as endangered. Its survival depends on conservation efforts to mitigate threats like habitat loss and road mortality.
Transient and Dispersal Zones
Mountain lions are occasionally sighted in Midwestern and Eastern states, but these areas do not support permanent, reproductive populations. These sporadic appearances are the result of a natural process called dispersal. Young cats are forced to travel hundreds, sometimes over a thousand, miles from their birthplace to find an unoccupied territory and avoid confrontation with older, established males.
States such as Nebraska, Kansas, Oklahoma, Minnesota, Iowa, Illinois, Wisconsin, and Michigan have all recorded verified sightings of dispersing mountain lions in recent decades. These transient animals are often individuals that have traveled eastward from the source populations in the Rocky Mountains or the Black Hills of South Dakota. One documented case involved a male mountain lion that traveled from South Dakota to Connecticut, a distance of over 1,000 miles, before being killed by a vehicle.
The presence of a transient animal does not signify the re-establishment of a population; rather, it represents a brief exploration into the former range. This has not occurred outside of the established Western and Florida populations. The transient sightings indicate the potential for the species to naturally recolonize parts of its historical range if suitable habitat corridors and prey are available.
Habitat Requirements and Historical Range
The current fragmented distribution of the mountain lion is a consequence of its ecological needs and historical human actions. Mountain lions are ambush predators whose survival depends on three primary factors: large, contiguous tracts of land, adequate cover, and a robust prey base. They require extensive home ranges, with males often covering over 100 square miles, underscoring the necessity of vast, undisturbed wilderness.
The preferred habitat consists of steep, rocky canyons, mountainous terrain, and dense forests that offer the necessary cover for stalking prey. The availability of large ungulates, particularly deer, is crucial, as they can constitute up to 80% of the diet. Where deer populations are absent or severely limited, mountain lions cannot establish a permanent presence.
Historically, the mountain lion possessed the widest range of any terrestrial mammal in the Americas, spanning nearly the entire contiguous United States. This vast territory began to contract drastically in the 19th and early 20th centuries due to widespread extermination campaigns and habitat fragmentation. The systematic killing of large predators pushed the species out of the entire Eastern and Midwestern United States, leaving only the Western strongholds and the isolated Florida panther population.