Mountain Lion (Puma concolor)
General Distribution
Mountain lions occur in all of the mountain ranges within the four national forests (Stephenson and Calcarone 1999). Known historic records of mountain lions in California exist for the San Bernardino Mountains and San Jacinto Mountains in the vicinity of Strawberry Creek (Grinnell and others 1937). Between 1992 and 1997, 26 accounts of mountain lions have been recorded on the Los Padres and Cleveland National Forests (USDA Forest Service file data). Beier (1993) reported a population of 20 adults in the Santa Ana Mountains on the Cleveland National Forest.
Systematics
Goldman (1946) recognized 14 subspecies in North America, three of which occur in California. Hall (1981) adopted Goldman's taxonomy. Felis concolor californica is the California subspecies found on southern California National Forest System Lands.
Habitat Requirements
Mountain lions are habitat generalists, inhabiting a variety of habitat types throughout California, from deserts to humid Coast Ranges (Dixon 1982). They are most abundant in areas that support a large population of deer, their primary prey. Within these habitat types, mountain lions tend to prefer rocky cliffs, ledges, and other areas that provide cover (Dixon 1982). They are rare at higher elevations in pure stands of conifers and at lower elevations in pure stands of chamise (Adenostoma fasciculatum). Fire plays an important role in determining the suitability of habitat for mountain lions. Fires, which reduce canopy closure, increase vigor and accessibility, and improve palatability of shrub species preferred by deer, will benefit mountain lion populations. In California chaparral, mountain lions were attracted to the edges of recent burns where deer tended to congregate (Quinn 1990). Fire exclusion can reduce habitat suitability for deer and consequently mountain lions.
Reproduction
Mountain lions reach sexual maturity at approximately 2.5 years of age, after which time they are capable of breeding throughout the year (Dixon 1982). They generally produce one litter every other year but can breed in consecutive years under optimal conditions. Gestation lasts 82–98 days, and litter size ranges from one to six (Dixon 1982). A peak in births occurs during the summer. In California, females commonly produce three kittens per litter (Torres and others 1996). Average lifespan is about 12 years in the wild, but mountain lions have been known to live up to 25 years in captivity. On average, only one kitten out of three survives to sexual maturity (Torres and others 1996). Adult male mountain lions are known to kill mountain lion kittens and sometimes eat them.
Daily/Seasonal Activity
Mountain lions are solitary, secretive, and elusive (Torres and others 1996). They are primarily nocturnal and commonly forage at dawn and dusk.
Diet and Foraging
Dixon (1925) determined the diet of mountain lions in California to be almost 80 percent mule deer. Because they are opportunistic feeders, mountain lions exploit whatever food source is available, including bighorn sheep, skunk, porcupine, rabbit, raccoon, badger, squirrels, mice, wild pig, and domestic animals (Currier 1983).
Territoriality/Home Range
The home range of adult males in California was reported to encompass more than 100 square miles (260 square kilometers) (Torres and others 1996). Female home ranges are generally much smaller, covering 20-60 square miles (52–155 square kilometers). The size of an individual's home range can vary from season to season and year to year, and is probably dependent on prey density and available stalking cover (Currier 1983). In areas where habitat is limited, population densities can reach 10 adults per 100 square miles (260 square kilometers).
Predator-Prey Relations
Mountain lions do not have any natural predators but compete for food with black bears, wolverines, coyotes, and bobcats where they coexist (Currier 1983). Mountain lions are heavily dependent on deer and do not occur in areas where deer are absent (Dixon 1982). Around communities, mountain lions are also believed to opportunistically consume dogs and cats that are allowed to run free. This helps reduce the number of unattended domestic animals on national forests. This may also account for higher mountain lion numbers around some communities, even when deer are at low densities (Loe pers. comm.). Mountain lions have been identified by the Forest Service and California Department of Fish and Game as potentially having an adverse effect on bighorn sheep populations in the San Gabriel Mountains. Increased predation on bighorn sheep is possibly a result of deer populations decreasing in the area as fire exclusion continues to contribute to poor habitat quality (Loe pers. comm.).
Literature Cited
Beier, P. 1993. Determining minimum habitat areas and habitat corridors for cougars. Conservation Biology 7: 94-108.
Currier, M.P. 1983. Felis concolor. Mammalian Species 200: 1-7. Published by the American Society of Mammalogists.
Dixon, J. 1925. Food predilections of predatory and furbearing mammals. Journal of Mammalogy 6: 34- 46.
Dixon, K.R. 1982. Wild mammals of North America: Biology, management, and economics. Chapman, J. A.; Feldhamer, G.A., eds. Baltimore, MD: The Johns Hopkins University Press.
Goldman, E.A. 1946. Classification of the races of the puma. In: Young, S.P.; Goldman, E.A., eds. The puma, mysterious American cat. Washington, DC: Wildlife Management Institute.
Grinnell, J.; Dixon, J.; Lindsdale, J. 1937. Furbearing mammals of California, their natural history, systematic status, and relations to man. Volume 1. Berkeley, CA: University of California Press.
Hall, E.R. 1981. The mammals of North America. 2d ed. Toronto: John Wiley & Sons. McCarthy, J.A.; Williams, J. 1995. Cougar. Montana Outdoors 6(22):24-28.
Quinn, R.D. 1990. Habitat preferences and distribution of mammals in California chaparral. PSW-202. Berkeley, CA: USDA Forest Service, Pacific Southwest Research Station.
Stephenson, J.R.; Calcarone, G.M. 1999. Southern California mountains and foothills assessment: Habitat and species conservation issues. General Technical Report PSW-GTR-172. Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture.
Torres, S.G.; Mansfield, T.M.; Foley, J.E.; Lupo, T.; Brinkhaus, A. 1996. Mountain lion and human activity in California: Testing speculations. Wildlife Society Bulletin 24: 451-460.
Information gathered from California DFG - California Interagency Wildlife Task Group