Until late 2009, it had never been seen. The only clues of its existence were fecal matter, slain deer and some paw prints discovered in 2005. Motion-activated cameras set up in 2006 never snapped a photograph of it. But in late 2008, Trevor Hebert, Jasper Ridge geographic information systems and data manager, began an experiment, installing a new motion-activated camera. Almost a year later, a photograph finally surfaced. The clues were confirmed. There was at least one mountain lion roaming Stanford’s Jasper Ridge Biological Preserve.

“It was amazing,” Hebert said. “I don’t think anyone believed that we would ever see one for some reason, and we’re still not sure why we didn’t see any mountain lions for those several years. Everyone was quite amazed when we saw that first picture.”

The photos started to, in Hebert’s words, “trickle” in. Through the winter and following spring, occasional pictures of the lion appeared on the cameras. Then, at the end of May 2010, the trickle intensified. Pictures flowed into the Jasper Ridge database for the rest of the summer. The stream finally slowed at the end of the season, although it never stopped.

In Sept. 2010, members of the Woods Institute for the Environment’s Rising Environmental Leaders Network (RELN) took on the project. Inspiration for the network came from two sources. First, the team was modeled on the Leopold Leadership Program (LLP), which brings together mid-career faculty from across North America to put environmental research to public use.

The second inspiration for the team came from a general recommendation made by the 2005 Stanford Commission on Graduate Education, said LLP program manager Margaret Krebs.

Jasper Ridge offered the interdisciplinary team of five graduate students and postdoctoral researchers three projects to pick from, and the team picked the mountain lion project. Team member and mechanical engineering graduate student Lena Perkins said an earlier encounter with a mountain lion sparked her interest.

“I saw a mountain lion 10 years ago up in Desolation Wilderness, and once you see them, I think everybody’s bitten by a little bit of fascination,” Perkins said.

According to the Jasper Ridge website, the team was assigned to answer how the risks from a mountain lion presence should be evaluated, managed and conveyed to Jasper Ridge users; how the camera trap data on mountain lions should be used and shared — and on what timeframe — for scientific, educational or management purposes; and if there were unique opportunities for Jasper Ridge to contribute to research and communication on mountain lion ecology in ways that are consistent with Stanford’s research policies.

The team gathered information by interviewing 15 experts in “mountain lion ecology, risk assessment, graphic communication, institutional liability, University policy on research on wild animals and regional conservation and coordination.”

Perkins said the team synthesized this information, along with additional material gathered from study of United States Fish and Wildlife policy and from correspondence with California Fish and Game, UC-Santa Cruz researchers, Audubon California Starr Ranch Sanctuary and Orange County Parks and Recreation, into a comprehensive report. They turned the report in for revision in July 2011, and it was recently published online on the Jasper Ridge website. A Stanford news article quoted the report’s conclusion that “there are likely at most only one male, one female and possibly several cubs whose territory includes the preserve.”

Perkins said two important opportunities that Jasper Ridge could pursue involve lion scat genetic analysis, which could help researchers find out the exact number of mountain lions in the area, and radio collaring. Both UC-Santa Cruz and a Bay Area non-profit organization are interested in helping Stanford start a radio-collaring project.

Perkins added that the presence of even a single mountain lion has major consequences for the Jasper Ridge ecosystem. By limiting the size of the deer population, mountain lions prevent deer from overgrazing, and the resulting increased number of plants in the area curbs erosion, improving the area’s water quality.

“The impact of a single mountain lion as a keystone species really shapes a lot of the topography essentially, and therefore the higher water quality and clarity means generally healthier fish populations,” she said. “It has really far-reaching implications, and certainly Jasper Ridge is uniquely poised to… do something there.”

Jasper Ridge Administrative Director Philippe Cohen said the preserve has already implemented a few of the team’s suggestions and said the preserve will “likely implement others” at some point.

In response to the report, a preserve protocol was created that restricts activities to daytime hours “unless staff is informed and approves of the activity.”

“This also includes our requiring that nobody goes out alone at night,” Cohen said. “There must always be at least two people present unless there are extenuating circumstances and require my explicit approval.”

Jasper Ridge Research Coordinator Nona Chiariello added that during the daytime, Jasper Ridge has “implemented strong, routine recommendations that users follow a buddy system, especially researchers who might be working crouched down for extended periods or might be in the field near dawn and dusk.”

In addition to this change, a wildlife photo gallery was created for the Jasper Ridge website, and the preserve also changed the wording of its waiver form.

“[The team] brought a fresh perspective based on expertise in other areas ranging from engineering to economics to marine biology to soil science; they thought hard, with open minds, and researched the subject carefully,” Chiariello said.

While the investigation has concluded, Hebert’s cameras continue to take pictures of the preserve’s wildlife. Since receiving a grant from the National Science Foundation, Hebert has installed more cameras — there are now 16 still cameras and two video cameras.

While the lion has been discovered, another question remains: how many lions are there? Hebert believes all the pictures are of the same lion, but he said it is difficult to know for sure. The lion photographed last year was smaller and less muscular than the lion that was photographed this year. Has the same lion grown? Probably. Could it be a different lion entirely? Possibly.