The term “desert river” may seem like an oxymoron but several major waterways slice through the southeast corner of Utah such as the Colorado, Delores, Green, and San Juan rivers.

Along their course, the river has carved deep canyons through millions of years of geologic history creating spectacular stretches such as Westwater Canyon, Richardson’s Amphitheater, Cataract Canyon, and Glen Canyon. At times the river is placid as it gently meanders past groves of cottonwoods and willow and tamarisk stands lining the river. Other times the river boils and churns over rapids with names such as Skull, White’s, and the Big Drops.

When the heat of summer makes hiking a challenge in the canyons, the place to be is on the river. Floating a stretch of river is a favorite summertime activity, but these river corridors are also great places to look for wildlife which live along the river.

As the river passes through southern Utah, it carries a lot of silt and debris washed down from above or carried to the river by numerous tributaries. The lack of clarity hides an essential component of the river ecosystem: fish.

Four of the 14 native fish species of the Colorado River drainage are Federally listed as endangered or threatened. Razorback sucker, Colorado pikeminnow, bonytail chub, and humpback chub are rarely seen except for anglers or wildlife biologists studying these creatures. For most visitors, the fish are “out of sight, out of mind,” but that doesn’t minimize their existence.

Three semi-aquatic species that may be observed while floating the river are river otters, beavers, and muskrats. Both muskrats and beavers inhabit ponds, and slow-moving sections of the river. Though it would be a beaver’s pipedream to dam the river, high water flows would blow out these structures. Instead, the beaver selects side tributaries or wetlands in which to build their dams and dens in slow moving water.

River otters are making a comeback in the Colorado River and its tributaries thanks to reintroductions by the Utah Division of Wildlife Resource which started back in the 1980s. Historically, these sleek creatures were ruthlessly trapped for their fur (same goes for the beaver and muskrat) and extirpated in many stretches of the river.

Though gracefully in the water, on land the animals hump along on webbed toes to den sites or when traveling overland. Even though the otter primarily feeds on fish, it will large aquatic invertebrates, amphibians, crayfish, small mammals such as young beavers or muskrats, and occasionally young ducklings or goslings.

Rivaling otters as supreme fishing creatures, great blue herons use their long bills like tweezers to grab a fish. With their long legs, the herons can stand in the water, often along the edge of the river or one of the sandy bars midstream. Stealth and patience are their strategies combined with a lightning-fast jab of their bill.

There are several heron rookeries along various stretches of the Colorado where birds nest near one another in a large cottonwood grove. Watching these birds fly in and land on their nests does not seem possible for such a gangly-looking bird, but they accomplish this feat with (mostly) grace and ease.

The streamside or riparian vegetation comprised of willows, tamarisk, coyote bush, cottonwoods, and other plants is also an excellent summer spot to bird watch. Warblers, vireos, grosbeaks, flycatchers, and other species nest in these protective thickets.

A highlight of any river trip is viewing desert bighorn sneaking down to the river for a drink or foraging on plants on the drier uplands. These majestic mammals are the quintessential desert dweller and even they know where to go during the heat of summer for a drink of water or a bit of shade.