Reintroduction pending. Colorado Parks and Wildlife released a formal Wolverine Restoration Plan in January 2026, targeting reintroduction of 45 animals over three years. No animals have been released yet; a federal ESA designation is required before the first release can proceed.
Overview
The wolverine (Gulo gulo) is the largest land-dwelling member of the weasel family — a muscular, bear-faced predator that looks improbable and behaves accordingly. It crosses mountain ranges in days. It drives grizzly bears off kills. It travels routes that would exhaust a backcountry skier. For an animal that weighs less than 40 pounds, it occupies an almost mythological space in the ecology of the high Rockies.
In Colorado, wolverines occupy a peculiar conservation status: present but not established. Camera traps and track surveys have confirmed individual wolverines in the San Juan Mountains, Never Summer Range, and other high-elevation zones over the past two decades. These are almost certainly animals dispersing from source populations in Wyoming and Idaho — scouts, in effect, testing whether Colorado’s alpine landscape can support a breeding population. So far, no confirmed breeding pairs have been documented in the state.
That framing is changing. Colorado passed Senate Bill 24-171 in May 2024, authorizing CPW to reintroduce wolverines to the state. On January 15, 2026, CPW released a formal Wolverine Restoration Plan — a 106-page document planning for 30 female and 15 male wolverines to be released over three years into Colorado’s high country. No animals have been released yet; the program is working through required state and federal steps before the first release.
After nearly three decades of legal battles, petitions, and withdrawn listing proposals, the U.S. Fish and Wildlife Service listed the wolverine as Threatened under the Endangered Species Act in November 2023. The listing explicitly identified climate change — specifically the loss of persistent spring snowpack — as the primary driver of decline.
Habitat in Colorado
Wolverines in Colorado are creatures of the high country in the most literal sense. Every confirmed detection has come from subalpine or alpine terrain above 10,000 feet — spruce-fir forest, krummholz, and alpine tundra. The Weminuche Wilderness in the San Juan Mountains represents the most consistently documented area in the state, though detections have occurred across multiple mountain ranges.
What makes habitat suitable is not just elevation but snowpack. Female wolverines den in deep spring snow, excavating tunnels that can extend 10 feet or more beneath the surface. The snow serves as insulation — keeping den temperatures stable while kits develop — and the den must hold through April and May when cubs are most vulnerable. Research has established that wolverines require persistent snowpack of at least five feet deep through the spring denning period. Colorado’s highest terrain currently provides this, but modeled projections suggest significant portions of that habitat become marginal by mid-century under most climate scenarios.
Males require enormous home ranges — often 200 to 500 square miles — which means suitable Colorado habitat must connect to larger populations to the north. Isolated mountain ranges surrounded by lower-elevation terrain act as barriers to dispersal.
Primary Threats
Climate change and snowpack loss is the threat that drove the 2023 federal listing. Wolverines are among the most climatically vulnerable mammals in North America because their reproductive biology is physically tied to deep spring snow. As snowpack arrives later, melts earlier, and decreases in depth across the Rockies, the window of suitable denning conditions contracts. Models project a 31–63% reduction in wolverine habitat in the contiguous United States by 2099. In Colorado, this compression occurs from below — as lower treeline sites warm, the band of suitable habitat retreats upslope toward summits that offer diminishing returns in terms of area.
Isolation and low connectivity compounds the climate threat. Colorado’s wolverine detections appear to be dispersers from Wyoming and Idaho source populations. For a breeding population to establish in Colorado, animals must successfully navigate hundreds of miles of fragmented terrain — crossing highways, developed areas, and lower-elevation habitat that wolverines typically avoid. A female making this journey is extraordinarily rare.
Low reproductive rate means any losses are slow to recover. Females typically breed every two years, producing litters of two to three kits. A population absorbing consistent adult mortality — from trapping, vehicle strikes, or habitat loss — cannot replace losses quickly.
Historical trapping eliminated wolverines from Colorado entirely by the early twentieth century. The state has been in a recolonization phase ever since, dependent on animals dispersing south from populations that were themselves reduced.
Recovery and Conservation Status
The November 2023 Threatened listing was the culmination of a process that began with the first formal listing petition in 1994. Intervening decades saw a 2013 proposed listing withdrawn under political pressure, subsequent litigation, and a 2020 court ruling that the withdrawal was unlawful. The 2023 final rule represents the first durable federal protection wolverines have received. The most famous Colorado wolverine was M56, a male tracked from Wyoming to Colorado in 2009 — the first confirmed wolverine in the state in nearly 90 years — before being shot in North Dakota in 2016.
Colorado moved quickly after the listing. In May 2024, Governor Polis signed Senate Bill 24-171, authorizing CPW to reintroduce wolverines to the state and allocating funds from the Species Conservation Trust Fund for the effort. The legislature committed approximately $1.7 million over four years to the program. On January 15, 2026, CPW released its formal Wolverine Restoration Plan — a 106-page document detailing the framework for reintroducing 30 female and 15 male wolverines over a three-year period into Colorado’s high country.
Colorado holds an estimated 20 percent of all modeled wolverine habitat in the contiguous United States, making it one of the most significant potential recovery sites for the species anywhere in its lower-48 range.
No release date has been set. Before animals can be moved, CPW must finalize a livestock depredation compensation rule and obtain a federal designation from USFWS that allows Colorado’s state-managed reintroduction to comply with ESA requirements. The latter step has become complicated by the current political relationship between Colorado’s wildlife management and the Trump administration, which has taken an adversarial posture toward several Colorado wildlife programs.
Critical habitat has not yet been designated for the wolverine. A recovery plan was pending at the time of the 2023 listing.
CPW monitors wolverine presence through remote camera networks and winter track surveys. The state’s wolverine program is now formally structured around restoration rather than passive monitoring.
What You Can Do
- If you observe what you believe is a wolverine in Colorado, report it to Colorado Parks and Wildlife through their wildlife observation system at CPW’s wolverine sighting form. Wolverine detections are rare and scientifically valuable; CPW biologists will follow up. A general area description — mountain range, wilderness unit, or county — is sufficient.
- Support snowpack and climate policy. Wolverine recovery in Colorado is inseparable from the trajectory of the Rocky Mountain snowpack. Organizations working on Western water and climate policy are effectively working on wolverine habitat.
- Follow CPW’s wolverine reintroduction process. Public comment opportunities will arise as CPW finalizes the livestock compensation rule and other steps required before releases occur. Engaged public support for the reintroduction is meaningful given the political headwinds the program faces at the federal level.
- Practice low-impact winter recreation in wolverine country. The Weminuche Wilderness and other high San Juan terrain represent the most likely areas for future wolverine activity in Colorado. Staying on established routes during late winter and spring minimizes disturbance during the period when wolverines, if present, would be denning.