While California's human population has been moving elsewhere in recent years, the state's big cat population appears to be adding residents from Nevada.
Mountain lions have been moving west from the Great Basin into the Sierra Nevada in contrast to biologist's expectations, according to a study recently published in the online version of Molecular Genetics.
Because mountain lion hunting is allowed in Nevada, but not in California, researchers anticipated more of the felines would head east as hunters killed the cats in Nevada and opened up territory for cougars living in California, said Alyson Andreasen, a doctoral student at the University of Nevada, Reno, and the lead author of the study.
But the opposite proved to be true following the analysis of 739 genetic samples from lions in both states.
"We were surprised by the fact that we found more movement from the Great Basin to the Sierra Nevada," Andreasen said.
The mountain range's relatively lush habitat may be attracting members of the reclusive species from tougher conditions in the Great Basin, Andreasen said.
Researchers don't have a firm grasp on exactly how many mountain lions are moving west. Andreasen said she hoped future studies, including ongoing studies involving collared mountain lions, would refine scientists understanding of the movement of the species, as well as the relationship between the cats and their prey.
Future efforts may also give scientists a better understanding of the movement of mountain lions on a smaller scale, like around the Lake Tahoe Basin, Andreasen said.
"This is the first, kind of large scale, study using these kinds of technologies," Andreasen said.
The research - a partnership between the University of Nevada, the Nevada Department of Wildlife and the Wildlife Conservation Society - was only recently completed and it's unknown how the findings may effect future management decisions, said Nevada Department of Wildlife spokesman Chris Healy.
But information contained in the study is very exciting and will help the agency in its decision-making process regarding the species, Healy said.
"The more you know about wildlife, the better you can manage them," Healy said.
The Nevada Department of Wildlife estimates there are between 1,200 and 1,300 adult mountain lions in Nevada. If juvenile mountain lions are included in the count, the estimate swells to about 3,000, Healy said.
The California Department of Fish and Game estimates there are between 4,000 and 6,000 mountain lions throughout California. Whether the population is increasing or decreasing is unknown because of a lack of an ongoing statewide study, according to the agency.