Conservation Genetics 4: 353–366, 2003. © 2003 Kluwer Academic Publishers. Printed in the Netherlands. 353 Genetic structure of mountain lion (Puma concolor) populations in

Analysis of 12 microsatellite loci from 431 mountain lions (Puma concolor) revealed distinct genetic subdivision that was associated with geographic barriers and isolation by distance in California. Levels of genetic variation differed among geographic regions, and mountain lions that inhabited coastal areas exhibited less heterozygosity than those sampled inland. The San Francisco Bay and Sacramento-San Joaquin River Delta, the Central Valley, and the Los Angeles Basin appeared to be substantial barriers to gene flow, and allele frequencies of populations separated by those features differed substantially. A partial barrier to gene flow appeared to exist along the crest of the Sierra Nevada. Estimated gene flow was high among mountain lions inhabiting the Modoc Plateau, the western Sierra Nevada, and northern section of the eastern Sierra Nevada. Southern California mountain lio