Desolation Canyon Wildlife Guide | Green River Endangered Fish, Bears & Bighorn Sheep
Desolation Canyon Deep Dive
Wildlife of Desolation Canyon
Biodiversity from 9,800 feet to 4,450 feet: mammals, birds, reptiles, and the endangered native fish of the Green River
← Back to Trip Planning Guide
A Canyon Ecosystem
The Green River cuts nearly 5,000 vertical feet through the Tavaputs Plateau, creating dramatic changes in vegetation and wildlife over short distances.
At the upper elevations, subalpine fir, blue spruce, and aspen communities prevail. Pinyon-juniper woodland dominates the mid-elevation slopes, and substantial stands of Douglas-fir extend down shadier north-facing canyon slopes. The canyon bottom supports Fremont cottonwoods, boxelders, willows, and coyote willow along riverbanks.
This wide elevational gradient means river runners encounter species adapted to desert heat at river level and glimpse high-altitude forest on the rim above. The natural landscape reflects complex interactions between geology, river dynamics, plants, animals, and climate, creating one of the richest ecosystems in canyon country.
Mammals
Bighorn Sheep
Ovis canadensis
Move easily through rough, craggy terrain using specially adapted hooves and superb balance. Mature males sport massive curled horns. Often depicted in Fremont petroglyphs along the river. Watch for them on steep canyon walls, especially in the deeper reaches of Desolation Canyon.
Black Bear
Ursus americanus
A substantial population ranges from the high Tavaputs to riparian habitats. Omnivorous, feeding on roots, fruits, animals, carrion, and carelessly cached camp food. Encounters are fairly common throughout the canyon. Bear-proof your food and trash. See BLM website for current recommendations.
Mountain Lion
Puma concolor
Feeds primarily on mule deer. Seldom seen, but tracks appear in beach mud and sand when cats come to the river to drink. Also known as cougar.
Mule Deer
Odocoileus hemionus
Named for their distinctive large ears. Forage on a wide range of plants across all life zones. Good swimmers that easily cross the river. Most retreat to high country in summer but are commonly seen at dawn and dusk near the river.
American Beaver
Castor canadensis
The largest North American rodent. Trapped to near extinction during the fur trade era, now a common river resident. Burrows in river banks, feeds on inner bark of cottonwoods and willows. Look for gnawed stumps and slides along the banks.
Bushy-tailed Woodrat (Packrat)
Neotoma cinerea
A handsome, nimble rodent that lives among cliffs and rocky crevices. Their conspicuous middens contain evidence of climate and vegetation change spanning 50,000 years, making them invaluable to researchers.
Birds
Canyon country birding at its best. Here are the species you're most likely to see from the river.
Great Blue Heron
Ardea herodias
Tall, lanky hunter of fishes and frogs in river shallows. Colonies nest in cottonwood trees. Stalks prey with deliberate patience, then strikes with lightning speed.
Golden Eagle
Aquila chrysaetos
Big cliff-nesting raptor that soars magnificently along canyon rims and swoops down on mammals, snakes, and other animals.
Canyon Wren
Catherpes mexicanus
Its lilting songs of descending whistles resonate off canyon walls. Probes its slim bill into crevices for insects. One of the most evocative sounds in the canyon.
Cliff Swallow
Petrochelidon pyrrhonota
Gregarious birds that carry mud pellets and construct colonies of gourd-shaped nests on riverside cliffs. Watch for clusters of mud nests on canyon walls throughout the trip.
Canada Goose
Branta canadensis
Common nesting river resident. Adults and young swim confidently and easily run rapids. Grazes on low riverbank plants.
Turkey Vulture
Cathartes aura
Often seen soaring along canyon walls on thermals. Nests on cliffs and steep rocky slopes. Uses airborne odors to find carrion.
Common Raven
Corvus corax
Canyon character that rides thermals, sometimes upside down. Scavenges campsites for leftovers and hillsides for carrion.
Chukar
Alectoris chukar
Large quail-like game bird introduced from southern Eurasia. Common in lower Gray Canyon. Listen for its distinctive repetitive "chuck-kar" call.
Reptiles & Amphibians
Midget Faded Rattlesnake
Crotalus oreganus
Desolation and Gray's only venomous reptile. A seldom-seen small snake. Lizards and mice dominate its diet. Give it space.
Eastern Collared Lizard
Crotaphytus collaris
Colorful, active, flashy. When chased, sprints on hind legs with forelegs and tail in the air. Sometimes eats other lizards.
Woodhouse's Toad
Anaxyrus woodhousii
Warty-skinned hopping amphibian of sandy bottomlands. Often active in riverside campsites after dark. Listen for drawn-out "waaaah" calls of breeding males.
Endangered Native Fish
Four of 13 native fish species in the upper Colorado River system are endangered. The unregulated flow of the Yampa River is crucial to their survival.
The upper Colorado River system contains only 13 native fish species. Although the fauna is small, it is highly unique, with extraordinary species that evolved to contend with extremely variable river conditions. Large dams have dramatically altered the rivers, and the fishes' formerly successful adaptations have become disadvantages as they contend with altered flows, temperatures, turbidity, loss of floodplain habitat, and dozens of non-native fish species.
Colorado Pikeminnow
Ptychocheilus lucius
The largest minnow native to North America. Historically reached 5-6 feet long and 60-80 pounds. In summer, spawning adults migrate up to 200 miles to reach specific spawning locations on cobble bars. The Green River through Desolation Canyon contains critical spawning habitat.
Humpback Chub
Gila cypha
Occurs primarily in turbulent, deep canyon reaches. The population in Desolation and Gray Canyons is the third largest, exceeded only by those in the Grand Canyon and the Black Rocks/Westwater reaches of the Colorado River. Feeds on aquatic invertebrates and terrestrial insects.
Bonytail
Gila elegans
Once common, now the rarest fish in the Colorado River Basin. Disappeared quickly after closure of the big dams. Being raised in hatcheries and stocked in the middle Green and Colorado rivers.
Razorback Sucker
Xyrauchen texanus
Specially adapted to feeding in floodplain habitats, with its distinctive boat-shaped "inverted keel" profile. Primary spawning bars are upstream near Jensen, UT, and Ouray National Wildlife Refuge.
Invasive Species Alert
Dozens of non-native fish species now inhabit the Green River, harming native fishes through predation and competition. Smallmouth bass, channel catfish, northern pike, and walleye are all present. Before launching, boaters must certify that boats are free from aquatic invasive species (quagga and zebra mussels). This is required by Utah law. Forms available at Sand Wash or online.
Full Wildlife Guide with Photos
Belknap's Desolation River Guide includes detailed Living Landscapes sections by biologist Geoff Hammerson covering mammals, birds, amphibians and reptiles, trees, shrubs, and flowers, plus endangered native fish and non-native fish sections by Dr. Ed Wick with full-color illustrations by Joseph R. Tomelleri.
Get Belknap's Desolation River Guide →Wildlife content based on Living Landscapes by Geoff Hammerson and Native and Non-native Fish by Dr. Ed Wick in Belknap's Desolation River Guide. Published by Westwater Books, Evergreen, Colorado.