Colorado Parks and Wildlife is investigating a suspected fatal mountain lion attack that occurred on the Crosier Mountain trail in unincorporated Larimer County. The incident happened around 12:15 p.m. when hikers reported seeing a mountain lion near a person lying on the ground about 100 yards away.

The hikers approached the scene and scared the lion by throwing rocks. When they reached the adult woman, they found she was unresponsive and had no pulse.

Local authorities responded to the area, including CPW officers, Larimer County Sheriff deputies, Estes Park police, and Glen Haven Area Volunteer firefighters. A CPW biologist who was conducting aerial deer surveys helped locate the animals and assist with transportation. Officials also used dogs to track the scent of mountain lion.

Officers located one lion at the scene and shot it. The animal ran from the area, but officers tracked and euthanized it. A short time later, a second mountain lion was found nearby and also euthanized.

It is unknown if one or multiple lions were involved in the attack. According to CPW policy, wildlife involved in attacks on humans must be euthanized to ensure public safety.

CPW pathologists will perform necropsies on the animals to check for abnormalities and diseases like rabies and avian influenza. The Larimer County Coroner will release the identity of the victim and cause of death.

Mountain lion attacks on humans in Colorado are rare, with only 28 previous attacks reported to CPW since 1990. The last fatal attack occurred in 1999.

In Larimer County and along the Front Range, hikers and outdoor enthusiasts should expect to encounter wildlife. Mountain lions are more visible in winter as they follow deer and elk to lower elevations.

If people spot a mountain lion, they should make noise to scare it away, hold objects overhead to appear larger, and slowly back away. Pets should be kept on a leash and not allowed to interact with wildlife.

Editor’s note: Portions of this article have been augmented with the assistance of Large Language Models for analysis, with human review, editing, and original material.