Grizzly Bears (Ursus arctos horribilis) have been absent from Rocky Mountain National Park (RMNP) for decades. While RMNP is a premier destination for viewing wildlife like elk, moose, and bighorn sheep, the largest predator in the park today is a different species of bear entirely.
The Definitive Answer
Grizzly Bears once occupied a vast historical range across western North America, including the mountains of Colorado and the area now encompassed by RMNP. Intense hunting pressure and habitat loss throughout the 19th and early 20th centuries led to a rapid decline. By the mid-1950s, the species was officially considered extirpated (locally extinct) from the entire state of Colorado.
The last confirmed Grizzly Bear in Colorado was killed in 1979 in the San Juan Mountains. Since then, no evidence of a resident population has been found in the state. Today, Grizzly Bears in the contiguous United States are restricted to isolated ecosystems much further north, primarily the Greater Yellowstone Ecosystem and the Northern Continental Divide Ecosystem in Montana, Idaho, and Wyoming.
The geographical distance between RMNP and these established populations makes a natural resurgence highly unlikely. Transient bears traveling hundreds of miles would face significant obstacles from human settlements and fragmented habitat. Therefore, visitors exploring RMNP can be certain that a Grizzly Bear encounter is not a possibility.
The Bears Visitors Will Encounter
The only species of bear currently inhabiting Rocky Mountain National Park is the American Black Bear (Ursus americanus). While their name suggests a dark coat, Black Bears in RMNP often display various color phases, including cinnamon, brown, or blonde. This color variation can sometimes lead to misidentification.
Distinguishing a Black Bear from a Grizzly Bear is possible by looking for specific physical markers. Black Bears generally lack the prominent, muscular shoulder hump characteristic of a Grizzly. They also have a straight facial profile, contrasting with the Grizzly’s noticeable “dished” face.
Black Bears possess shorter, more curved claws adapted for climbing trees, while Grizzly Bears have long, straighter claws suited for digging. Behaviorally, RMNP’s Black Bears are shy and omnivorous, with about 90% of their diet consisting of vegetation, berries, and insects. They generally prefer to avoid human contact.
Staying Safe in Bear Country
Proper food storage is the most important component of bear safety in RMNP, as most human-bear conflicts occur when bears gain access to human food or garbage. All scented items must be secured in bear-resistant containers or lockers provided at campgrounds. Backcountry campers are required to carry and use hard-sided, commercially-made bear-resistant food storage canisters below the treeline between April and October.
When hiking, visitors should make noise by talking or clapping, especially when moving through dense forest or around blind corners, to avoid surprising a bear. Hiking in groups is also safer, as a larger presence can help deter an encounter. Bears accustomed to human food sources often lose their natural fear, which can ultimately lead to their removal or death.
If an encounter does occur, the protocol for a Black Bear is distinct from that of a Grizzly. Visitors should never run, as this may trigger a predatory chase response. Instead, stand your ground, make yourself appear large, and speak loudly. If a Black Bear attacks, the most appropriate response is to fight back using any means necessary, rather than playing dead.