Overlapping Mountain Lions
F61 and F51, adult female mountain lions (Puma concolor), also called cougars, followed by Panthera’s Teton Cougar Project were both four years old when they gave birth to their first litters of kittens within a month of each other in 2011. The pair of big cats were neighbors in adjacent and overlapping home ranges in the Bridger-Teton National Forest, east of Grand Teton National Park in northwest Wyoming, USA.
A well-placed motion-triggered camera caught a fortuitous image of F61 and F51 spending time together in early 2012, accompanied by their four kittens (1 from F61, 3 from F51). It sparked great discussion among our team, many of whom were convinced they must be close relatives, perhaps sisters. Indeed, prevailing theory supported the idea that close kin were more likely to be close to each other and tolerant of one other. Thus, it just made sense that the two cats would be kin. At the time, however, we did not know the genetic relatedness of cougars in our study, except of course, kittens born to females we were tracking.
Mountain lions are solitary carnivores expected to interact only during the breeding season or to settle territorial disputes. In short, we expect cougars to avoid each other. The two prevailing ecological theories explaining the spatial organization of animals within populations are the land-tenure and kinship theories (e.g., Diefenbach et al. 2006; Griffiths & Armstrong 2001). The land-tenure predicts territorial behaviors—females use smaller home ranges that provide the necessary resources to sustain themselves and their kittens, while males utilize larger home ranges that provide access —> Read More