A mountain lion killed crossing the 118 Freeway earlier this month has been identified as P–39, a female that was traveling with three 6-month-old kittens, wildlife officials said Thursday.

"Mountain lions need to move,” Beth Pratt Bergstrom, California director for the National Wildlife Federation, told KPCC. “[Her death was] almost predictable given that these home ranges they have to traverse are intersected by so many freeways and highways in this area. It just highlights the challenges these cats face.”

P–39 was the 13th mountain lion hit and killed trying to cross a road or freeway since 2002, when biologists began studying the animals in the area, according to National Park Service spokesperson Kate Kuykendall. P-39 was estimated to have been 5 years old.

“Navigating this complex network of roads in Southern California is a huge challenge for wildlife here,” Kuykendall told KPCC, adding that the 13 believed to have died represents the number of animals killed that biologists were aware of in the study area and that it was possible the real number is higher.

Park Service biologists have been studying mountain lions in the areas around the Santa Monica Mountains to see how they survive in an increasingly fragmented and urbanized landscape. As part of an awareness campaign, the Santa Monica Mountains Recreation Area even created a profile page featuring more than 50 big cats being tracked.

P–39 was one of those animals, and because she was equipped with a GPS collar, biologists were tipped off when she was pregnant. Biologists discovered she had a new litter of kittens in July, and photos of the blue-eyed cubs took social media by storm.

"On the 118, if there was better fencing, it might have led her to better to a place to cross," Bergstrom said. Planting trees and bushes to guide mountain lions and wildlife to safe crossing places, as well as reducing speed limits, could also help, Bergstrom said.

The park service received word that a mountain lion was killed crossing the 118 Freeway near Chatsworth on Dec. 3, but not until days after the accident had occurred. By the time they were able to get to the scene to investigate, the remains were long gone, Kuykendall said.

That made it difficult to confirm that it was in fact one of the animals they were tracking. P–39’s collar had already stopped sending signals, and the last transmission was in the vicinity of the accident. Still, it wasn’t until Wednesday, when a biologist returned to the scene with the person who originally reported the accident, that P–39’s damaged collar was identified near the center divider, according to Kuykendall.

What about the kittens?

The prognosis for the kittens’ survival is not good, according to Seth Riley, a wildlife ecologist with the Park Service.

Mountain lions normally stay with their mother for 12 to 18 months, and it is during that time they learn critical hunting skills, Riley told "Take Two." Because the cubs were only about 6 months old, it’s unlikely they have attempted hunting on their own.

Regardless, it’s unlikely anyone will find out what happened to them, since they are not wearing GPS collars, Riley said.

“Mountain lions use these huge areas, so we just have no idea where they would be,” he said.

Even if they could be found, California prohibits capturing mountain lions and then re-releasing them into the wild. According to Riley, that's because the animals could get too accustomed to human interactions and lose their fear.

Why is this a big deal?

A lot of animals get killed crossing roads and freeways, but for big cats and other large carnivores, each death can have real impact.

Because carnivores spread out and range across larger regions, there are simply fewer of them.

“In the case of mountain lions, especially reproducing adult females like this, each one can be pretty important to the population,” Riley said.

One small consolation might be where P–39 roamed, though. The mountain lions that roam near the Santa Susana Mountains have better access to less developed land to the north, Riley said. In contrast, the lions of the Santa Monica Mountains have been plagued with loss of habitat and inbreeding.

Kuykendall said she hopes the death of another mountain lion will help raise awareness and support of a wildlife corridor.

Efforts have been underway to put a wide overpass with natural turf and plants across the 101 Freeway in Agoura Hills. Bergstrom said that the $60 million overpass is needed to protect mountain lions.

“It’s 10 lanes, first of all. It’s also funnel point. There’s only a few a few other options on that corridor where there isn’t development on both sides of the freeway," Bergstrom said.

So far, the National Wildlife Federation has raised $1.5 million and recently got a pledge of a $1 million matching grant from the Annenberg Foundation for the corridor. They need to get to $10 million by mid-2017 to stay on track.

Even if a corridor is installed, though, there’s no guarantee the animals will find their way to it. Riley said more will be needed.

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