Use of Road Track Counts as Indices of Mountain Lion Presence

Interactions of mountain lions (Felis concolor) with roads and the effectiveness of searches for tracks on roads as a means of assessing mountain lion populations were examined in Arizona and Utah on 3 study areas. Road crossing frequencies were related to total home area road densities of individual lions. Unimproved dirt roads were crossed most frequently. Improved dirt roads and hard-surfaced roads were crossed less often and were less likely to occur within lion home areas, suggesting possible avoidance. Seventy searches for mountain lion tracks on roads were conducted in southern Utah in areas where densities and distributions of radio-collared mountain lions were known and where tracking conditions on roads were measured objectively. Changes in the density of resident female lions explained 61% (r2= 0.61) of the variation in track finding rates under ideal conditions. Under all tracking conditions, resident females required the least effort to detect (51.1 km searched/track set found) of all population cohorts. All resident lions, 78% of transient lions, and 57% of cubs were detected by track searches. Use of road track searches as indices of mountain lion populations is discussed.