A runner then took video of the lions where the Courdet Trail meets the Ridge Line Trail.
The video was shot by a Davor Desancic, who had gone running on the trail on Monday morning. He says he recorded the video around 6:15 a.m. Desancic said he didn't hear the mountain lions, he just suddenly saw them.
We asked him if he felt threatened since we're not talking about one or two mountain lions but four of them. Desancic told us he didn't feel threatened since they were 500 or so feet away. They didn't stop at all either. He said it appeared that there were three juvenile lions and an older one. Desancic's thought was that that was their mother. We showed the mountain lion video to hikers, some of whom have seen mountain lions before, but not a group or family of them in the wild.
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"If I had been the one taking that video, I definitely would have been like - okay, that's a little scary there. I think it was kind of trippy because we just hiked that trail so kind of seeing where we had just been and then seeing the lions, that was kind of cool," said a hiker by the name of Camille.
"I just think that it is awesome that there is this kind of wildlife thriving in the Bay Area. They're usually not dangerous if you stay away from them," said another hiker by the name of Danny.
We reached out to those with East Bay Regional Parks, California Fish and Wildlife, and Pleasanton police to see if they were aware of the group of mountain lions. Everyone aware that there are mountain lions in the park areas, but those we talked to didn't know about what appeared to be a family.
Experts say that most of the time mountain lions are calm, quiet, and elusive but if you do see one - stay calm, hold your ground or back away slowly. Do not approach a mountain lion or run from one.