LOS ANGELES (CBSLA) – New research has found that issues including habitat loss, inbreeding and isolation could cause cougar populations in the Santa Monica and Santa Ana mountains to go extinct within the next 50 years.
According to a study published Wednesday in the journal Ecological Applications, the probability of extinction is between 16 to 28 percent for mountain lions in those ranges.
“Our model predicts that there is a moderate probability of extinction in these two populations over the next 50 years, even before we considered genetics,” the study’s lead author, University of Nebraska wildlife ecologist John Benson, told the Orange County Register.
The researchers termed the problem an “extinction vortex.” In the Santa Monica Mountains, the 101 Freeway exists as barrier for a group of about 7 adult mountain lions and 8 kittens, the Register reports. In the Santa Ana Mountains, the 15 Freeway limits the movement of about 16 adult lions and 13 kittens.
The study found that inbreeding and the lack of fresh genes poses the greatest threat to these cougar populations, according to the Register.
The study also noted that wildfire and disease could result in “catastrophic mortality” and further hasten the animals’ disappearance. Earlier this month, National Park Service biologists became concerned after discovering a case of skin disease in P-53, a female mountain lion in the Santa Monica Mountains, which could be linked to rat poison. According to NPS, mange is rare among mountain lions. Since 2002, only five mountain lions in the Santa Monica Mountains have contracted mange. Two of them, P-3 and P-4, died of rat poisoning.
In November, NPS reported that P-74, a male mountain lion, is believed to have died in the devastating Woolsey Fire.
Caltrans has long proposed building a wildlife bridge across the 101 Freeway in Agoura Hills that would allow animals to travel between the Santa Monica Mountains and Simi Hills. Meanwhile, conservationists have proposed capturing cougars in the Santa Anas and trucking them across the 15 Freeway so they can breed with other mates who are also isolated on the other side.
The study found that over the past 15 years, only five male mountain lions have successfully crossed freeways into the Santa Monica and Santa Ana ranges, the Register reports.
Eighteen cougars have been killed on a freeway or road in the Santa Monica Mountains since 2002, according to NPS. Between 2013 and 2018, at least four mountain lions died crossing the 15 Freeway, the study’s researchers told the Register.
At this time, mountain lions in California are not classified as endangered.
(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. City News Service contributed to this report.)