Over the last several decades, the
Santa Monica Mountains's mountain lion population has declined and
become genetically isolated, primarily due to the
Ventura Freeway that prevents them from moving between the
mountains and the
Simi Hills to the north. Since 2002, at least a dozen mountain lions have been killed on the freeway), and GPS tracking collars show that most approach the freeway then turn back, while only
one was able to repeatedly cross. In 2020, biologists found the first evidence of physical abnormalities in the isolated population. Wildlife crossings, meant to allow animals to circulate through habitats
fragmented by human development, would allow newcomers to bring new
genetic material to the area and would also allow mountain lions born in the area a chance to leave, in the case of males before they are killed and in the case of females to prevent future
inbreeding. The Wallis Annenberg Wildlife Crossing will be the first bridge in the
California highway system designed specifically for wildlife connectivity. Scientists identified Liberty Canyon, about northwest of
downtown Los Angeles, as the best location for the crossing in a 1990 study commissioned by the
Santa Monica Mountains Conservancy. The crossing is situated along a wildlife corridor within the
Santa Monica Mountains National Recreation Area that consists of thousands of acres of local, state, and federally
protected lands that stretch from Los Angeles into
Ventura County. Other species expected to benefit from this crossing include
bobcats,
coyotes,
gray foxes,
birds of prey,
skunks,
rodents,
American badgers,
American black bears,
fence lizards, and
mule deer. == Design ==