SACHA PFEIFFER, HOST:
Nearly two years ago, ferocious fires burned through Southern California's Santa Monica Mountains, west of Los Angeles.
MARY LOUISE KELLY, HOST:
The Woolsey fire killed three people and destroyed or damaged some 2,000 homes and buildings. The flames eventually scorched about half the mountain range.
SETH RILEY: I mean, it was just, like, moonscape. Like, there was a ton of area where there was just nothing left, almost.
PFEIFFER: Seth Riley is a wildlife expert with the National Park Service. He says in addition to destroying human lives, the fires consumed crucial habitat for mountain lions.
RILEY: You know, we already have limited area in the Santa Monica Mountains because it's surrounded by freeways and development, and then you burn half of it.
KELLY: Now there's a sign of rebirth. Over the summer, park service biologists say five mountain lion moms gave birth to 13 kittens. That is a record number of kittens in the 18 years the park service has kept count.
RILEY: And that's just way more - we've never had more than, I think, three in any one year.
PFEIFFER: Yet despite this baby boom, Riley says the lions still face existential threats. Scientists have predicted that the region's mountain lions could go extinct in the next 50 years.
KELLY: Yeah. One reason is that highways and developments have siphoned off a large, healthy population into tiny pockets with low genetic diversity. This summer, biologists discovered a young male lion with physical abnormalities caused by inbreeding.
RILEY: And the interesting thing there - right? - is that those are exactly the same things that they were seeing in Florida panthers in the early '90s when that population was on the verge of extinction.
PFEIFFER: Riley says the Florida panthers ultimately rebounded, thanks to the introduction of new cats from Texas. But he hopes that scientists in California can increase genetic diversity with a more localized approach.
RILEY: In Florida, that population doesn't have any other populations anywhere nearby, whereas, fortunately in California, we do have mountain lions all across the state. And there are big, genetically healthy populations not that far away.
KELLY: True, but freeways are a big barrier. They slice through the habitats. And in the Santa Monica Mountains, Riley says Highway 101 is a treacherously wide road for mountain lions to cross.
PFEIFFER: So the park service has plans to build the lions their own highway - an overpass that will let them safely roam from one side of the freeway to the other.
RILEY: So it's going to be very wide and vegetated and hopefully feel like, you know, relatively natural habitat.
KELLY: Riley says there are only two places on the whole planet where big cats live within megacities - leopards in Mumbai and mountain lions in Los Angeles. The hope is this wildlife bridge will allow humans and big cats to continue to coexist.
NPR transcripts are created on a rush deadline by Verb8tm, Inc., an NPR contractor, and produced using a proprietary transcription process developed with NPR. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.