MT. TAMALPAIS, Calif. (KGO) -- For the past three years, 100 motion-activated cameras have been tucked around Mount Tamalpais in Marin County, snapping photos of anything that moves, day or night.
The cameras have taken almost four million photos that are now being analyzed to learn more about which animals live on Mount Tam and their behaviors.
The project is called the Marin Wildlife Picture Index. It's overseen by One Tam, a partnership of national, state and county park departments, the Marin Municipal Water District, and the nonprofit Golden Gate National Parks Conservancy.
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The picture project was started after public land managers realized they were missing basic information about the mammals believed to live on Mount Tam and in the protected land around it.
The cameras have taken so many photos, One Tam Community Science Program Manager Lisette Arellano recruited dozens of volunteers to help sort the pictures. Volunteers gather every few weeks at the Water District headquarters in Corte Madera to scroll through thousands of shots, looking for animals.
Volunteer Meagan Porterfield said the process is like a treasure hunt. Sometimes the animals in the photos are obvious, but often finding the creatures can be very challenging.
Volunteer Chris Anderson showed us a night photo with a fuzzy dark shape. You have to look very carefully to see two little ears that indicate the shape is actually a deer.
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The cameras are designed to be as unobtrusive as possible but the animals still sometimes find them.
Volunteer Anne Libbin discovered photos of a clever coyote who apparently heard a camera clicking and "stuck his nose on the lens." Libbin had to advise the people who maintain the camera to clean the lens because of a "nose smear."
Arellano said the expert analysis of the photos is just beginning, but they have already found some surprises.
"We were able to see animals that we weren't really sure were on the mountain, like spotted skunks, the psychedelic cousins of your regular, run-of-the-mill striped skunk," Arellano said.
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Other unexpected photos show a badger in the woods. Badgers are usually found on grasslands, but a lot of Marin County grassland has been badly degraded, so badgers in the area are rare.
"It is a sign of hope to see them on the mountain," Arellano said.
The photos confirm there are mountain lions on Mount Tam, but fewer than in some other parts of Marin. There are also quite a few photos of adorable bobcat kittens and gray foxes doing everything from playing on trees to sneezing on a dusty trail.
Researchers say all this information about where animals are going, what they're eating, and how they're raising their young will be critical to future efforts to protect Mount Tamalpais and the open space around it.
Funding for the Wildlife Photo Index comes from private donations and the public agencies responsible for the land around Mount Tam. If you'd like to volunteer or see more pictures, click here.
Multi-year photo project captures animal life on Mount Tamalpais