Intraspecific Killing Among Mountain Lions (Puma Concolor)

Reports of intraspecific strife among mountain lions (Puma concolor) have been presented in the literature. However, there are no published accounts of an actual field observation of lion behavior during an incidence of intraspecific strife. Here we provide a report of such an incident, in which a female mountain lion was killed by a male mountain lion in rural El Dorado County, California, in 2002. Observations from a field investigation of the site and the results of the necropsy of the female also are presented. The investigation indicated that the female lion was healthy and was not pregnant, lactating, or in estrus. Mortal injury was a skull fracture resulting in brain damage and hemorrhage. We suspect the female might have been killed while defending a deer kill or as prey of the male lion.