The mountain lion known as P-81, pictured here, is among the first in the Santa Monica Mountains with a tail defect. Credit: National Park Service |
Southern California cougars often make the news with their litters of oh-so-cute kittens, but a UCLA-led study suggests that these mountain lions may soon find it much harder to reproduce due to a lack of genetic diversity.
Scientists tracking two local mountain lion populations, one in the Santa Monica Mountains and another in the Santa Anas, have identified the first reproductive signs of inbreeding among these groups, which are cut off from other cougar populations — and therefore breeding options — by busy freeways.
The animals averaged a whopping 93% abnormal sperm rate, while some also displayed physical signs of inbreeding, like deformed tails or testicular defects. Researchers have long had genetic evidence of inbreeding, but the malformed sperm is the first evidence that inbreeding is manifesting in the reproductive system.
“This is a serious problem for an animal that’s already endangered locally,” said the study’s lead author, Audra Huffmeyer, a UCLA postdoctoral researcher who studies fertility in large cat species and is a National Geographic Explorer. “It’s quite severe.”