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Los Angeles seems like a surprising home for a large wildlife predator.
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In fact, LA is one of only two mega cities in the world to have big cats living within the city limits.
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In LA, the freeways have sliced the mountain lion's habitat into ever-shrinking pieces.
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And this isolates the populations from each other and causes problems with genetic diversity.
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All leading to a risk of local extinction in as few as 12 years.
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But there's hope in saving them by re-linking these lonely lions, even one at a time.
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If one individual could come across every two or three years,
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then the genetic makeup of the population would stay fairly stable.
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Seriously, it only takes the introduction of one new mountain lion to renew genetic health for
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the local species.
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But before we get into that, let's explore how mountain lions got into this situation,
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or more specifically, how we forced them into this situation in the first place.
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Mountain lions live in a variety of habitats in Southern California.
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So they are sort of everywhere that there is cover, habitat and deer.
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We tend to attract some wildlife because of our lawns and our watered areas and our golf courses and things like that.
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So mountain lions oftentimes live much closer to people than we think.
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At the lower elevations and the passes and things where highways, have been built,
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The freeways carve the area up, and they make it such that the animals
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can't reach from one area to another very easily at all.
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Either get killed trying to cross, or the highway itself is so noisy,
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and there's so much light relating to cars that they just can't, they don't want to try it.
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So, although there are quite a few mountain lions living in the Southern California mountain ranges,
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and they've been there for thousands of years, the highways are now forcing individual mountain lions
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to stay where they are, without roaming to new areas as they naturally would.
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They tend to become inbred, they tend to keep breeding with each other,
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they don't have new animals coming in to introduce new genetics and so that inbreeding phenomenon,
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then leads to potentially health problems and susceptibility to disease, reproductive issues.
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Then the population could go extinct or, in the models, actually did go extinct within that 12 or 13 year period.
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So, it can happen quickly. If reproduction rates can't keep up with mortality rates.
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Unfortunately, Dr. Vickers has seen this before.
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The only mountain lion population we have as an example of what happens with inbreeding
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is the the Florida Panther, and it was isolated and is isolated in the Everglades
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and southern Florida.
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And when its population became low because of all of these same factors, and by low I mean
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less than 20 individuals in the entire state, they also were tending to just breed with each other.
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They also started having physical abnormalities changes in their haircoats, kinked tails
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were one thing that they saw.
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Cleft palates, physical abnormalities that began to show up because of inbreeding.
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Female mouth lions were brought in from Texas to breed with that population, and that was a successful
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introduction of genetic material, and the kitten survival went up, and overall survival went up, and the population
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has now expanded to between one and 200 animals.
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In the case of the Southern California mountain lions, conservationists don't want to translocate the animal.
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But what they really want is to enable the mountain lions to move themselves. And one of the best way to
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mountain lions for genetic purposes, is to link one wild area to another, with a network
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of well-disguised movement corridors and road crosses.
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Wildlife corridors aren't a new idea. They've worked in many other areas with other animals,
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a wildlife corridor could be anything from a fish ladder, a tunnel for toads, or a highway overpass.
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Creating passageways across I-15 or improving the existing passageway can certainly allow animals to come
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across the freeway more freely than they do now.
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And that could be enough.
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Overpasses allow the mountain lions to roam freely and mix their gene pools,
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without ever having to dash across traffic.
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Currently, two wildlife overpass projects are being proposed - one over the interstate 15
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in Western Riverside County.
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And another over the US-101 freeway in Los Angeles.
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In 2011, one of the lions that successfully made it across without a bridge proves just how helpful mixing
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individuals can be.
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That was M86, a male mountain lion that found mates in the Santa Ana mountains, after migrating from a
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genetically diverse population.
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He had 11 detected offspring, adding the desperately needed unique genes into the inbred population.
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So far we've only documented one in 15 years that was successful.
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M86 was hit by a car and killed the next time he tried to cross.
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And of course, having these mountain lions so close to humans poses its own challenges, even if the populations
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are able to mix together.
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Many locals worry about having large predators so close to their backyards, pets, and children.
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As top predators they, like wolves and bears, tend to regulate the ecosystem through their prey behavior,
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with their behavior toward prey.
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So they reduce deer numbers, versus what would be present if they weren't there.
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And that can help to downregulate things like vegetation types and browsing levels and things that affect other
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animals down lower on the food chain.
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There's been some work that suggests that their role regulating deer populations has not only promoted vegetation
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balance, but also helps to reduce roadkill and collisions with cars, which endanger humans.
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Of course, it really helps to preserve large spaces of wild land, before we build on it. Rather than trying to
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put the pieces back together after the fact
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I think the role of our populace of people who care about mountain lions is to become more and more
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active in the conservation of land and the conservation of animals and in whatever way might be
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suitable to them because local decisions, oftentimes really determine a lot of these habitat issues.