Mountain lions living in the Santa Monica and Santa Ana mountains must boost genetic diversity or risk local extinction. New findings in a UCLA-led study document the first signs of inbreeding in mountain lion reproductive systems — these include a 93% abnormal sperm rate, deformed tails and testicular defects.
Audra Huffmeyer, UCLA Department of Ecology and Evolutionary Biology postdoctoral researcher and National Geographic Explorer, leads this research, which also builds upon work from the National Park Service’s Santa Monica Mountains Recreation Area and the UC Davis Wildlife Health Center.
The Santa Monica and Santa Ana mountain lion populations are isolated from other groups, limiting mating options and therefore genetic diversification. This disconnect is caused by large, busy freeways. Researchers are therefore advocating for the implementation of wildlife crossings, structures which would allow the mountain lions and other animals to cross man-made barriers. Able to roam further, cougars would then have access to the broader mating pools needed to prevent local extinction.
Findings from this study are of particular importance for reasons beyond their signal of cougars’ risk of local extinction. Mountain lions are known as a bellwether species. This means their reproductive struggles associated with inbreeding indicate that inbreeding may soon cause problems for other wildlife in the Santa Monica and Santa Ana mountains. Biodiversity and ecosystems would be severely negatively affected should this come to fruition, making wildlife crossings now more urgent than ever.
Learn more about the study’s research methods, results and proposed solutions at UCLA Newsroom.
Study Authors
Audra A. Huffmeyer, Department of Ecology and Evolutionary Biology, UCLA
Robert K. Wayne, Department of Ecology and Evolutionary Biology, UCLA
Jeff A. Sikich, Santa Monica Mountains National Recreation Area, National Park Service
Seth P.D. Riley, Santa Monica Mountains National Recreation Area, National Park Service
T. Winston Vickers, Karen C. Drayer Wildlife Health Center, UC Davis
Image Source: National Park Service
