Migratory patterns of mountain lions: Implications for social regulation and conservation

Abstract

We studied movements of mountain lions (Puma concolor) in the southern Sierra Nevada of California from 1992-1997. We observed two distinct patterns, which likely represent strategies of mountain lions for coping with variability in abundance of their primary prey, mule deer (Odocoileus hemionus). Some mountain lions migrated together, often slowly, following movements of mule deer from winter range toward the summer range of their prey. Those mountain lions remained together on the eastern scarp of the Sierra Nevada and overlapped in distribution throughout the year. Other mountain lions exhibited rapid movements to disjunct summer ranges, on the western side of the Sierra Nevada, shared with mountain lions that did not occur on their winter range. Mountain lions that moved more slowly and overlapped in distribution had large annual home ranges (95% adaptive kernel; X̄ = 817 km2), whereas mountain lions with distinct summer (X̄ = 425 km2) and winter (X ̄= 476 km2) distributions had smaller home ranges. Such disparate patterns of movement may lead to difficulties in sampling population size for mountains lions. Moreover, maintaining corridors that would allow for both patterns of movement may be critical for the conservation of these large felids. Finally, extensive overlap in the distribution of mountain lions, especially the association of one group of individuals on winter range and another on summer range for mountain lions with disjunct distributions, indicates a more flexible social system than previously described.