A Colorado woman died Thursday, January 1, in what officials believe was a suspected mountain lion attack.
Authorities found a mountain lion roughly 100 yards away from the woman, whose identity had not been released as of publication, around 12:15 p.m. on the Crosier Mountain trail in unincorporated Larimer County. Colorado Parks and Wildlife said hikers scared the lion away before checking on the woman. One of the witnesses, a physician, did not find a pulse.
Colorado Parks and Wildlife is investigating the death as a suspected mountain lion attack. According to the agency, the last fatal mountain lion attack on a human was in 1999. There have been 28 attacks reported since 1990, fewer than one per year. Eleven of those 28 attacks have occurred in northeastern Colorado, an area that includes Larimer County.
CPW spokesperson Kara Van Hoose said agency biologists euthanized two mountain lions they found nearby “in accordance with CPW policies.” A necropsy will reveal if they were involved in the attack or had any diseases.
A woman was killed in a suspected mountain lion attack while she was hiking alone in the mountains of northern Colorado on Thursday — the state’s first fatal attack in over 25 years, officials say. pic.twitter.com/JnzWcaBEEN
— ABC News (@ABC) January 2, 2026
According to Denver7, first responders closed all three Crosier Mountain trailheads and the Houston Heights Trailhead while investigating. CPW estimates there are roughly 3,800 to 4,400 mountain lions in Colorado.
“This is an area where mountain lions are very common, along with a lot of other wildlife — bears and moose,” Van Hoose said.
It is believed the woman was alone when she died. As of publication, it remained unclear whether she had been hiking alone the entire time or had been separated from someone else or a group.
According to Colorado Parks and Wildlife (CPW), the incident occurred on Wednesday and, if confirmed, would be the first fatal mountain lion attack in the state since 1999. A group of hikers discovered the woman’s body on a secluded trail and reported seeing a mountain lion… pic.twitter.com/hSYg1NHW45
— anreads (@newyorktaxcon) January 2, 2026
CPW shared several tips for hikers who encounter a mountain lion:
- Do not approach a lion, especially one that is feeding or with kittens.
- Talk calmly and firmly to the lion, and never turn your back on it.
- Stop or back away slowly, and do not run. CPW says running “may stimulate a lion’s instinct to chase and attack.”
- Do all that you can to appear larger, including raising your arms and opening your jacket if you’re wearing one.
- Protect your children so they don’t run.
- Throw stones, branches, or anything nearby to try to convince the lion that you are not prey.
- Fight back only if necessary, aiming for the eyes or nose.
A 31-year-old man encountered a mountain lion in Fort Collins, Colo., while walking in 2019. He escaped without significant injury, though he required 25 stitches on his face and three on his wrist.
“I think it’s one of those really weird sensational stories — super rare,” Travis Kauffman said then. “I feel like I should go buy a bunch of lottery tickets… It’s a modern-day man vs. nature scenario.”
