Mountain Lions in the Berkeley Hills
Mountain lion photo from the Bay Area Puma Project remote cameras
Hiking through the Berkeley Fire Trails always seems like a relaxing experience after a busy day of online classes, meeting, and projects. Coast live oak, deer, and other chaparral wildlife are certainly comforting sights. But during dusk and dawn, it is not uncommon for a crepuscular predator to roam through the hills.
An iconic species of the Americas, Puma concolor, is known by many names: Puma, Mountain Lion, Cougar, León de Montaña, Miztli, Onza Bermeja, Leão da Montanha, and many others. There are names for 32 different subspecies throughout the Americas, but genetic analyses suggest there are only 6.Here in Berkeley, and the rest of North America, we are most familiar with P.c.cougar, although there is a limited range of P.c. coryi in Florida.
Historically, the mountain lion has had the most extensive range of any terrestrial mammal in the Americas. The species was very abundant in North America until hunting for livestock protection throughout the 1800s and early 1900s decimated the eastern populations. However, the populations have remained relatively stable and the International Union for the Conservation of Nature (IUCN) lists the mountain lion as a species of least concern.
Mountain lions are an “umbrella species” because a large amount of protected habitat, which can benefit other wildlife, is required for their conservation. As a generalist species, they thrive in a variety of habitats including forests, savannas, shrublands, grasslands, and deserts. The predators use their stealth for a diet of mainly deer, but can include other small animals and even insects. A carnivorous diet is needed for their large size; males weigh between 115 and 220 pounds while females weigh between 64 and 141 pounds. Habitat destruction from urban development continues to threaten mountain lion habitat and increase the risk of conflict, which may lead to deadly consequences.
About half of California is ideal habitat for the mountain lion and it is estimated that there are 4,000 individuals in the state. Although the population trend is slightly decreasing, interactions between people and mountain lions are becoming more frequent. The California Department of Fish and Wildlife is tasked with the responsibility to address the risk of mountain lions on the landscape.
In 1990, Prop 117 in California passed to prohibit the sport hunting of mountain lions. There are only three exceptions that allow killing a mountain lion: if a depredation permit is issued for a specific problem individual, to preserve public safety, or to protect threatened bighorn sheep. Only about 60 individuals are legally killed each year. Many Californians enjoy outdoor recreational activities in mountain lion country, and it is important to follow safety precautions. If you encounter a mountain lion, remember to keep facing the animal, back away, make lots of noise, wave your arms to look bigger, and throw rocks or other objects.
Mountain lion attacks on humans are very rare; there have been less than 20 verified attacks since 1986 of which only 3 were fatal. The most recent incident was in San Diego last June where a 4 year-old boy survived minor injuries. Extracted DNA from the scratches were then used to identify the mountain lion, which was eventually located and put down. Mountain lions are also a risk for pets and predation in human-dominated landscapes is not rare. The California Fish and Wildlife Department performs necropsies on legally taken individuals to produce an annual report on findings. The most recent report of 2019 analyses revealed that 67 mountain lions were necropsied and 5% contained remains of domestic pets. The Mountain Lion foundation shares tips such as keeping pets indoors, cleaning garbage, and others to keep your pets safe in mountain lion country. Research on predator behavior in human-dominated landscapes is especially important for conservation and safety.
The Bay Area consists of landscapes with varying degrees of development, providing a unique study site for human-mountain lion dynamics. Audubon Canyon Ranch is a North Bay environmental conservation and education non-profit organization leading the Living with Lions initiative. The project works on capturing and collaring mountain lions to identify priority habitats and key wildlife corridors. In 2018, the project formed a partnership with Dr. Justin Brashares who leads the Brashares Lab here at UC Berkeley to expand the study area and collaborate on research. Research from the Brashares Lab, Middleton Lab, and partners provide insight on the future of human-wildlife coexistence and how management and policy can be adapted to promote coexistence.
The Santa Cruz Puma Project led by UC Santa Cruz and the California Department of Fish and Wildlife is another hub of research on the physiology, behavior, and ecology of mountain lions in the Bay Area. The project created the Puma Tracker tool which allows the public to track the movement and home ranges of individual mountain lions throughout the Santa Cruz Mountains. Give the tool a try and imagine the range of landscapes these predators must navigate.
These initiatives and tools provide insight on the role of mountain lions as a keystone species throughout the Americas. Research on mountain lions, wolves, and other carnivores is essential to mitigate human-wildlife conflict and develop management strategies that support local communities and conservation. Next time you are on a hike in a natural space, consider the influence of development such as trails, roads, fences, and houses on the mountain lions and other predators that call California home.
