Marin Wildlife Picture Index Project Results Rolling In

May 5, 2016


Marin County, CA—Wildlife cameras installed in Mt. Tam’s open spaces a year and a half ago have begun revealing some surprising things about the mountain’s furry residents. Volunteers have helped catalog hundreds of thousands of photos, which have shed light on the activities of rare mammals like river otters and western spotted skunks—a species that may be in decline. A good number of carnivores, which play a critical role in ecosystem health, have also been caught on camera, including gray foxes, coyotes, bobcats, and even a one-eyed mountain lion. 

The agencies that care for Mt. Tam are entrusted with protecting all the animals that live there, as well as those that may just be passing through. While land managers are aware of many of the species that may be found on and around the mountain, there are many things they do not know about their abundance, how they move across the landscape, or how they might use different areas over the course of the year. Mammals, while responsive to changes in habitat quality, are particularly difficult to study directly so remote cameras offer a way to gather valuable information about these important ecological indicators.

“Mt. Tam is part of a network of protected areas and open spaces that are vital natural refuges and corridors for wildlife. The more we know about when and how animals use different habitats, the better we can protect these creatures and the resources that they need.” said Janet Klein, Natural Resources Program Manager with the Marin Municipal Water District

The motion activated cameras are stationary and weatherproof so they can be left outside for long periods of time. Because they do not emit light or use a flash, they can take pictures day or night without disturbing the animals. The cameras were installed as part of a broader international Wildlife Picture Index Project (WPI) first developed BY the Wildlife Conservation Society and the Zoological Society of London and now supported by HP Enterprise Services and Conservation International.

Cameras were placed in a variety of habitat types throughout the Lagunitas Creek corridor. Sites on all of the One Tam partner agencies lands—including Marin County Parks and Open Space District, California State Parks, the National Park Service, and the Marin Municipal Water District—were chosen to help show how mammals are using these interconnected landscapes. 

“This project is a truly wonderful example of what we can accomplish when we all work together to meet a common need,” said Kevin Wright, Government and External Affairs Coordinator for Marin County Parks. “It has allowed us to leverage the knowledge and resources of each of the One Tam agency partners, and combine that with the support of the Golden Gate National Parks Conservancy to address the resource protection goals that are at the very heart of our work.” 

Around 160 volunteers have signed up to help staff members comb through the 1.5 million images collected by the cameras. Photos of mammals are identified and retained, but pictures of people or pets are not. Classes from Redwood High School, San Rafael High School, City College of Marin, City College of San Francisco, and San Francisco State University have also come by to lend a hand and learn about the project. 

“We’re always seeking ways to engage the public and provide opportunities for people to connect with and appreciate our parks,” said Bree Hardcastle, Natural Resources Manager with California State Parks. “People feel a real affinity for wildlife and having new information and captivating photos to share has given us an exciting new way to demonstrate why these places are so important.”

At least 15 different native mammal species have been photographed since the cameras were installed in September 2014. Black-tailed deer are the most common, accounting for roughly over half of the catalogued photos, followed by gray squirrels, small rodents, and raccoons. Three non-native species—opossums, cows, and turkeys—also have been detected by the cameras. Other highlights include:

  • Cameras on Marin Municipal Water District lands captured spotted skunks, and one of two mountain lions photographed so far. 
  • Cameras at Samuel P. Taylor State Park have revealed a second mountain lion, as well as rarer species such as the spotted skunk and the river otter. Although not part of the study, more bats have been photographed at this site.
  • Roy’s Redwoods Preserve and French Ranch Open Space Preserve have had the highest detection rate for coyotes, but the lowest for gray foxes.
  • The Gary Giacomini Open Space Preserve is one of only two sites where opossums have been photographed more than just a few times. Grey foxes are also more abundant here than at any of the other Marin County Parks and Open Space Preserves. 
  • The working landscapes of Point Reyes National Seashore revealed one mammal not seen elsewhere—cows. It also had the highest number of opossum sightings, which was unexpected as this species usually prefers more densely populated areas.

Photos and summaries for each site are available at and projects/wildlife camera project. For information about volunteering for this project, contact Jacob Kurzweil at

About the Tamalpais Lands Collaborative (TLC) and One Tam Partners:

California State Parks
The California State Parks are dedicated to providing for the health, inspiration and education of the people of California by helping to preserve the state's biological diversity, protecting its most valued natural and cultural resources, and creating opportunities for high-quality outdoor recreation.

Golden Gate National Parks Conservancy
The Golden Gate National Parks Conservancy is the nonprofit membership organization that supports the Golden Gate Recreation Area. Since 1981, the Parks Conservancy has provided support for site transformations, trail improvements, habitat restoration, research and conservation, volunteer and youth engagement, and interpretive and educational programs. In Marin, the Conservancy has restored habitat and trails, engaged youth and volunteers, and managed a variety of wildlife and plant monitoring programs. Learn more at

Marin County Parks
Marin County offers an extensive system of regional and community parks, open space preserves, and trails for public use and enjoyment. It is dedicated to educating, inspiring, and engaging the people of Marin in the shared commitment of preserving, protecting, and enriching the natural beauty of Marin's parks and open spaces, and providing recreational opportunities for the enjoyment of all generations.

Marin Municipal Water District
Marin Municipal Water District is a public utility providing water to 186,000 people in south and central Marin County, and managing 21,635 acres of watershed lands open to public use. In operation since 1912, MMWD is the oldest municipal water district in California. The district’s mission is to manage natural resources in a sustainable manner and to provide customers with reliable, high-quality water at a reasonable price. 

National Park Service
The National Park Service (NPS) is a federal agency within the U.S. Department of the Interior charged with managing the preservation and public use of America’s most significant natural, scenic, historic, and cultural treasures. The NPS manages the Golden Gate National Recreation Area, which includes Mount Tamalpais, as well as 401 other park sites across the U.S.