Remote Camera Carnivore Study

For the past three years, Park District biologists have amassed an extraordinary collection of photos, video and data of the carnivores living in the Sunol and Ohlone wilderness areas. While most of these carnivores are rarely seen by park visitors, this unique research project has provided an invaluable glimpse into the lives of our most cryptic and elusive creatures.

Using motion-triggered remote cameras affixed to trees and fences, researchers have attained high-quality footage of mountain lions, coyotes, bobcats, gray foxes, and badgers, among other animals, as they move, eat, sleep, hunt and are hunted.

The cameras, placed in both wooded riparian areas as well as higher-elevation ridgetops, have allowed biologists to learn about predation, relationships between species, how animals appear to be coping with the drought, and other information that until now has been difficult to obtain.

So far, the images have shown that the remote East Bay hills support viable populations of carnivores, but the drought could be having an impact. For example, the black-tailed deer population appears to be declining, which will likely affect mountain lions and other carnivores that prey on them.

As part of a long-term biodiversity project, the remote camera study is improving our understanding of the ecological relationships and population dynamics of wildlife in the Sunol-Ohlone Regional Wilderness.  Funding for this research was provided in part by the Regional Parks Foundation and Chevron Corporation.

Here are some facts about the native carnivores in our parks:

Mountain lions

  • Also known as puma, cougar, catamount
  • “Specially protected” in California
  • Females weigh 70 to 90 pounds, males weigh 120 to 160 pounds
  • Rarely seen by people
  • Predominantly preys on deer


  • Named for its short tail
  • Lives in most areas of the U.S. and Mexico
  • About twice the size of a house cat
  • Preys on squirrels, rabbits, mice, birds

Gray foxes

  • Weighs 8 to 15 pounds
  • One of the few animals in the dog family that can climb trees
  • Nocturnal and semi-arboreal (spends much of its time in trees)
  • Eats eggs, fruit, nuts, and berries in addition to small mammals and reptiles


  • One of the more vocal animals, often yipping and howling at night
  • Hunts in packs
  • About the dimensions of a medium-sized dog
  • Depicted in Native American folklore as a trickster