Fraser Shilling is the Director of the Road Ecology Center at UC Davis and says California's car culture is hard on mountain lions. "Mountain Lions being hit by cars has been going on probably ever since there were cars on highways in California," said Shilling. "In California, we have so much traffic, so many roads that where mountain lions are moving, we've built barriers. We've built road barriers; we've also built moving barriers that could stop them or kill them when they try to go there." As apex predators mountain lions traverse large areas looking for resources this usually means they have to cross a road. "They might be really hungry, they're in search of a mate, they're young males dispersing away from an adult mountain lion, and sometimes that puts them in conflict with the road." Some of the highest death rates occur where the human population is the largest, the San Francisco Bay area and here in Southern California. https://www.cbs8.com/article/news/local/outreach/earth8/californias-car-culture-and-its-impact-on-mountain-lions/509-1966e241-958c-4729-b3cc-fa935c144b99