Inbreeding could be the end for Southern California mountain lions, but there’s still a way to save them – Orange County Register

LOS ANGELES – Scientists monitoring two local mountain lion populations, one in the Santa Monica Mountains and the other in Santa Anas, have identified the first reproductive signs of inbreeding between packs. this, which is cut off from fertility options due to busy highways.

According to the UCLA-led study — available online and to be published in the January 2022 edition of the journal Theriogenology — the animals had an average rate of abnormal sperm of 93%, while some There are also physical signs of inbreeding, such as deformed tails or testicles. defects.

Researchers have long had genetic evidence of inbreeding, but malformed sperm is the first evidence that inbreeding is manifesting in the reproductive system.

“This is a problem,” said lead author Audra Huffmeyer, a UCLA postdoctoral researcher who studies fertility in big cats and a National Geographic Explorer. severe for an animal species that is already locally threatened with extinction. “It’s pretty serious.”

The researchers say the results underscore the urgency of the need to intersect with wildlife, structures that allow mountain lions and other animals to roam farther and find see more potential mates. Mountain lions – also known as cougars – are a species with a similar tether, making them a leading indicator that inbreeding could soon cause problems for other species in the Santa Monica and Santa Ana mountains.

The California Department of Transportation has scheduled ground breaking work in early 2022 for one such wildlife highway overpass, a bridge over Highway 101 in Agoura Hills, thanks to a combination of funding. public and private.

Biologists and land managers hope the project will lead to more crossings. Initial plans are being made for a possible structure on Interstate 15 in Riverside County.

The latest study builds on work from scientists from UCLA, the National Park Service’s Santa Monica Mountains National Recreation Area, and the UC Davis Wildlife Health Center. Both NPS and UC Davis are conducting long-term studies of Southern California mountain lion populations, currently tracking 17 cats.

Over the past year, the team has identified nine adult males from the Santa Monica and Santa Ana ranges with signs of inbreeding, including the first evidence of reduced fertility.

Their findings are similar to the signs of severe inbreeding seen early in most Florida cheetahs in the 1990s, including folded tails, underdeveloped testes, and teratogenicity (60% of spermatozoa). anomalous or more), Huffmeyer notes. Florida leopard populations only recovered with the arrival of mountain lions from Texas.

“Florida leopards are also isolated and severely interbred, so the fact that we are seeing similarities in our mountain lion populations is alarming,” she said. speak. “If we didn’t do anything to introduce more genetic diversity to Southern California mountain lions, we would have more males with reproductive problems, fewer kittens, and a better survival rate. of lower kittens.”

Scientists suggest true extinction of mountain lions in the Santa Monica and Santa Ana ranges. According to 2016 and 2019 papers assessing population viability, it included scientists from UCLA, NPS, UC Davis, the University of Wyoming, and the University of Nebraska.

While a few mountain lions – particularly the P-22 cougar, which frequents Griffith Park – have successfully crossed the freeway, many more have been killed attempting to do so.