Claws, Cars and Casualties: How Cougars Die in L.A. – National Park Service (.gov)

National Park Service biologists perform measurements during P-32’s necropsy. | Photo: National Park Service
[Update: Since this post was published, two more mountain lions in the study have died, one due to rodenticide and the other to intraspecific conflict. These deaths are not included in the numbers below.]In 2004, just a couple years into our study of mountain lions in the fragmented Santa Monica Mountains and surrounding area, the first two deaths occurred. Both deaths happened within a month of each other. Both were the result of rodenticide poisoning. And both lived north of the 101 in the Simi Hills and Santa Susana Mountains. 
That was surprising news. To our knowledge, there had never been a documented mortality of a wild mountain lion due to rodenticide until then. And it happened twice in the span of 30 days.  
To a common person, this might seem like the start of trend. But two data points do not make it so. Data need breathing room and, in this case, that means time. Eleven years later, the study is still going strong with more than 40 lions included. 
So what has over a decade of study told us about the causes of mortality for local pumas? Let’s break it down. 

P-22, the lion living in Griffith Park, was exposed to rodenticide, making him susceptible to mange. He was treated and recovered. | Photo: National Park Service
Last updated: December 15, 2015
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