Dispersal movements of subadult cougars from the Black Hills: the notions of range expansion and recolonization

Dispersal plays a vital role in cougar (Puma concolor) population ecology, creating genetic viability and maintaining gene flow between populations. The naturally recolonized cougar population in the Black Hills is at the edge of the species' range in North America and completely surrounded by the grasslands of the Northern Great Plains. Our objective was to document dispersal movements and possible range expansion of subadult cougars captured within the Black Hills ecosystem of southwestern South Dakota and eastern Wyoming. Twenty-four (n = 14 males, n = 10 females) subadult cougars were captured in the Black Hills. Independence of cougars from females averaged 13.5 months (range = 10-16 months) from parturition; dispersal occurred 1-3 months post independence. Males dispersed (mean = 274.7 km SE 88.3) farther than females (mean = 48.0 km SE 10.9), with females exhibiting 40% philopatry. We documented several (n = 6) long-distance dispersal movements (>250 km) of male cougars and hypothesize that males making long-distance movements were in search of available mates. The long-distance cougar dispersal movements documented by our study indicate that range expansion and habitat recolonization are occurring and further suggest proactive efforts to increase public knowledge of cougar ecology in areas where cougars are recolonizing previously occupied range.