Learning To Live İn Mountain Lion Country

Researchers at Stanford's Jasper Ridge Biological Preserve often encounter signs of mountain lion activity, from lion scat to the occasional deer carcass covered with leaves. But few have actually caught a glimpse of the shy feline. Now, images captured by remote wildlife cameras confirm that mountain lions (also called pumas or cougars) make regular visits to Stanford's 1,189-acre preserve in the hills five miles west of the main campus.

Since September 2009, a network of motion-activated infrared cameras has recorded more than 40 photographs and videos of mountain lions in different areas of the preserve. Most of the images were captured between dusk and dawn, occasionally along trails frequented by docents, researchers and staff. However, an analysis of 30 lion photos from summer 2010 suggests that one animal triggered all of the images.

"The cameras are running 24 hours a day," said Trevor Hebert, Jasper Ridge's data manager. "Basically, anything that moves in front of them that's alive will trigger a picture."

The photos suggest a seasonal pattern of lion activity over the last two years, Hebert said, with more visits occurring during the dry months from May to September.

"One of the very encouraging things about all of the mountain lion pictures is that we know that we essentially have an intact ecosystem with the top predator actively killing deer," Hebert said. "We weren't always sure that was the case."

An upsurge in mountain lion photos last spring led the Jasper Ridge advisory committee to recommend a review of preserve policy. In June 2010, Jasper Ridge staff invited a group of Stanford students to serve as academic consultants on the review.

The students were part of the Rising Environmental Leaders Network, a pilot project of Stanford's Woods Institute for the Environment designed to give postdoctoral scholars and graduate students an opportunity to participate in a real-world consulting experience. The project was modeled after the Woods Institute's Leopold Leadership Program. Nicole Ardoin, a member of the Jasper Ridge advisory committee, served as the faculty leader.