Two decades of studying mountain lions has provided researchers with a wealth of information. Regarding mountain lion mortality, we’ve learned that anticoagulant rodenticide poisoning (rat poisons) is one of the leading causes of death.
Researchers believe mountain lions are exposed through secondary or tertiary poisoning, meaning that they consume an animal that ate the bait, such as a ground squirrel, or an animal that ate an animal that consumed the bait, such as a coyote.
Twenty-eight out of 29 mountain lions tested in the study have tested positive for one or more anticoagulant compounds and seven have died from anticoagulant rodenticide poisoning (as of December 2021).
Other major causes of death in mountain lions include intraspecific strife (mountain lions killing other mountain lions) and vehicle strikes.) Since 2002, at least 32 mountain lions (collared and uncollared) have been killed by vehicles on the many busy roads, highways, and freeways in the region (as of December 2022).
Click on the links below to learn more about the more notable mountain lion deaths.
P-015 (the first case of poaching); P-038 (this cat was illegally killed when it was shot in the head)
Road Mortality
P-009 (the first roadkill of a radio collared mountain lion in the study);
P-018 (this cat’s dispersal path led him to the 405 Freeway and getting hit by a car near the Getty Center on-ramp); P-061 (this cat was the first GPS radio collared mountain lion to cross the 405 Freeway but he was killed several months later in the same section of the freeway when trail camera footage showed him being chased by another mountain lion on the east side of the 10-lane highway); Other road mortality deaths include: P-023, P-032, P-039, P-049, P-051 and P-052, P-078
Rodenticide
P-030 (this cougar died of rodenticide poisoning); P-034’s (this cat’s death marked the study’s third case of mortality directly from rodenticide poisoning); P-047 (lab results indicate this cat may have succumbed to rodenticide poisoning); Other anticoagulant rodenticide-related deaths include: P-003, P-004, and P-076
Other
P-022 (this cat was captured by California Department of Fish and Wildlife due to a sudden change in his behavior and unfortunately euthanized upon poor health evaluation results); P-056 (this cat was killed under state depredation law in 2020); P-074 (his last GPS point was recorded the same day the Woolsey Fire moved into the central portion of the Santa Monica Mountains. He likely succumbed to the fire).
Locations:Santa Monica Mountains National Recreation Area
P-104 was a subadult male mountain lion who was hit and killed by a vehicle going northbound on the 33100 block of Pacific Coast Highway (PCH) on the morning of March 23, 2022.
Locations:Santa Monica Mountains National Recreation Area
He lived to be old enough to disperse, but died trying to define his own territory. P-018, along with his sisters, P-017 and P-019, were born in the Santa Monica Mountains in the spring of 2010 to male P-012 and female P-013.
Locations:Santa Monica Mountains National Recreation Area
P-022 was our most famous mountain lion and was known as our “Hollywood Cat.” He was a resident of Griffith Park in the city of Los Angeles and, at about 12 years old, he was one of the oldest cats in our study.
Locations:Santa Monica Mountains National Recreation Area
The only male in the 2013 litter of four birthed by P-013 to P-012. P-030 was last captured in February 2018 and researchers placed a new GPS collar on him at that time. The interesting thing about P-030 is that he is the first male lion kitten we have marked at the den to have survived long enough in the Santa Monica's to reach adulthood and establish a home range.
Locations:Santa Monica Mountains National Recreation Area
Unlike her litter siblings, P-032 and P-033, this female remained in the Santa Monica Mountains. She still did make the news, though, in her own way when she was caught in a stunning photo and later that day found under a mobile home park trailer in December 2014. Again, she made headlines for a more unfortunate reason when a jogger in Point Mugu State Park found her body on the trail.
Locations:Santa Monica Mountains National Recreation Area
P-047's remains were discovered on March 21, 2019 after his GPS collar sent out a mortality signal and NPS biologists hiked in to find him in the central portion of the mountain range. He did not have any visible wounds. Lab results indicate he may have succumbed to poisoning from anticoagulant rodenticide, commonly known as rat poison.
Locations:Santa Monica Mountains National Recreation Area
P-056, a 4 to 5-year-old male mountain lion that was living in the western Santa Monica Mountains south of the 101 Freeway, was killed under state depredation law on January 26. This marks the first time that a radio-collared mountain lion has been killed under a California Department of Fish & Wildlife (CDFW) depredation permit in the Santa Monica Mountains. Read press release here.
