The mountain lion known as P-61, who successfully managed to cross the 405 Freeway in the Sepulveda Pass in July, was struck and killed Saturday on that same section of the freeway, park officials said.
The Santa Monica Mountains National Recreation Area posted the following on its Facebook page at about 10:30 a.m.: "At around 4 a.m. on Saturday, September 7, we believe that the mountain lion known as P-61 was struck and killed on the 405 Freeway in the Sepulveda Pass. His final GPS point indicates that he was between Bel Air Crest Road and the Sepulveda Boulevard underpass.
"California Highway Patrol was initially alerted and moved P-61 out of traffic. City of Los Angeles Animal Control officers then retrieved his body and the radio-collar and notified both California Department of Fish and Wildlife personnel and our researchers here at Santa Monica Mountains National Recreation Area.
"The four-year-old cat had crossed the massive 10-lane freeway near the Sepulveda Pass area just a couple of months ago. Researchers are not sure why P-61 decided to try and cross the 405 Freeway again. Based on his GPS points, he had been staying close to the eastern edge of the 405 more recently. Over the last few years, we and others have gotten remote camera photos of an uncollared male mountain lion that apparently lives in that area. A negative encounter between the two could have caused P-61 to move back west."
Last month, researchers said they thought P-61 managed to cross the freeway from west to east between 2 and 4 a.m. on July 19.
The only other lion known to have crossed the 405 Freeway is Griffith Park's famed resident lion P-22.
That lion was not being tracked with a GPS collar at the time, so little is known about where and when he made the trek.
According to the National Park Service, another lion named P-18 was fatally struck by a vehicle in the same area of freeway while attempting a crossing in 2011, and another lion that was not being tracked by researchers was struck and killed in 2009.
Freeways acting as physical barriers to migration have long been identified as threats to the continued survival of mountain lions in the area.
At least one study has suggested that the lions will be extinct within 50 years due to the lack of breeding partners, leading to rampant inbreeding among the current population.
An $87 million wildlife crossing bridge -- financed largely by private donors -- is being planned for the 101 Freeway in Agoura Hills. Supporters hope to have it finished in 2023.