Eight distinct ecoregions — from shortgrass prairie to alpine tundra — each home to species
found nowhere else on Earth.
Shortgrass Prairie
Eastern Plains — 3,500–5,500 ft
Colorado's eastern plains stretch into Kansas and Nebraska, forming one of the most ecologically stressed landscapes in the state. Dominated by blue grama and buffalo grass, this region supports prairie dogs, burrowing owls, and the reintroduced black-footed ferret. Over 95% of historic shortgrass prairie has been converted to agriculture.
Key Species
Black-footed Ferret
Mountain Plover
Burrowing Owl
Swift Fox
Primary Threats
Agricultural conversion
Prairie dog control
Sylvatic plague
Energy development
Piñon-Juniper Woodland
Western Slope & Mesa Country — 5,500–7,500 ft
The scrubby, aromatic woodland of Colorado's western slope provides critical habitat for mule deer, black bears, and several raptor species. Increasingly threatened by drought-driven die-offs exacerbated by climate change, these woodlands are also vulnerable to invasive species and energy extraction.
Key Species
Mexican Spotted Owl
Gunnison Sage-Grouse
Colorado River Cutthroat Trout
Primary Threats
Drought and die-off
Cheatgrass invasion
Oil and gas development
Overgrazing
Sagebrush Steppe
Northwestern Colorado — 5,000–7,000 ft
The sagebrush sea of northwestern Colorado represents one of the most biologically rich and most threatened ecosystems in North America. The Gunnison sage-grouse — found nowhere else on Earth — depends entirely on intact sagebrush for food, cover, and breeding display grounds.
Key Species
Gunnison Sage-Grouse
Greater Sage-Grouse
Pronghorn
Sage Thrasher
Primary Threats
Energy development
Cheatgrass invasion
Drought
Fragmentation
Montane Forest
Foothills & Lower Mountain Zones — 6,000–9,000 ft
Ponderosa pine and Douglas-fir forests blanket Colorado's foothills, transitioning to mixed-conifer as elevation increases. These forests are experiencing unprecedented stress from mountain pine beetle outbreaks, wildfire, and drought — cascading into habitat changes for cavity-nesting birds and riparian-dependent species.
Key Species
Canada Lynx
Boreal Toad
Flammulated Owl
White-headed Woodpecker
Primary Threats
Wildfire
Mountain pine beetle
Climate warming
Urban interface development
Subalpine Forest & Meadows
High Mountain Slopes — 9,000–11,500 ft
Spruce-fir forests and lush subalpine meadows support some of Colorado's most climate-vulnerable species. The American pika — an indicator species for climate change — is retreating upslope as warming eliminates its cool talus habitat. Wolverines, if any remain in Colorado, persist only at these elevations.
Key Species
American Pika
Wolverine
Boreal Owl
Colorado Cutthroat Trout
Primary Threats
Climate warming
Spruce beetle outbreak
Ski area development
Recreational pressure
Alpine Tundra
Above Treeline — 11,500 ft+
Colorado's alpine tundra — above treeline and below permanent snow — is among the most fragile environments in the American West. Growing seasons of 6–8 weeks leave little margin for error. Climate change is compressing this zone from below as treeline advances upslope.
Key Species
White-tailed Ptarmigan
American Pika
Wolverine
Primary Threats
Climate warming (treeline advance)
Recreational overuse
Air pollution (nitrogen deposition)
Riparian Corridors
Statewide (along waterways) — All elevations
Though riparian zones cover less than 1% of Colorado's land area, they support over 80% of the state's wildlife species at some point in their life cycles. Colorado's rivers — the Arkansas, Rio Grande, South Platte, Colorado — are critically over-appropriated, leaving many native fish in chronically dewatered conditions.
Key Species
Razorback Sucker
Colorado Pikeminnow
Boreal Toad
Southwestern Willow Flycatcher
Primary Threats
Over-appropriation (water diversions)
Channelization
Invasive tamarisk
Groundwater pumping
Colorado Plateau Canyon Country
Southwestern Colorado — 4,500–8,500 ft
The canyon country of Mesa Verde, the Uncompahgre Plateau, and the Dolores River corridor harbors endemic species found nowhere else on Earth. Ancient rock formations, cryptobiotic soil crusts, and desert seeps create microhabitats for species with extremely limited ranges.