Colorado River Wildlife, Size, Activities, and More

Written by Carrie Woodward
Updated: July 21, 2023
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The Colorado River is a significant and vitally-important waterway in the western part of North America. This long, flowing river travels 1,450 miles through 11 different national parks and monuments. It flows through the diverse landscapes of seven states and two countries. It provides critical water for cities, agriculture, and industry and is part of the functioning economy. This winding river also provides ample opportunity for recreational activities that themselves contribute $26 billion to the United States national economy. The Colorado River has a long and storied history. Over the years, it has played an essential role in history and will continue to be a vital part of the North American environment, economy, and culture for years ahead.

Infographic about the Colorado River.
The Colorado River runs through several states and carved the Grand Canyon.

The Colorado River

At 1,450 miles long, the Colorado River is the sixth longest river in the United States. The Colorado River basin itself covers 260,000 square miles – that’s 8% of the continental United States! This river flows through many of the United States’ national parks and monuments. These include one of the most iconic: the Grand Canyon. In total, the Colorado River crosses seven states in the western U.S. It travels through Arizona, California, Colorado, New Mexico, Nevada, Utah, and Wyoming. It begins in the Rocky Mountains and ends at the border of Mexico. In doing, it is a vital source of water to cities including Las Vegas, Los Angeles, San Diego, Phoenix, and Tucson. 

colorado river

At 1,450 miles long, the Colorado River is the sixth longest river in the United States.

©Beth Ruggiero-York/

The Importance of the Colorado River

However, throughout its history, the Colorado River has done much more than simply provide water for human consumption in cities and for farming work. This river has been used for transportation, recreation, and fishing. As the river passes through different states and regions in the western United States, it provides a home for numerous fish and aquatic species. It also plays an essential part in the habitat of diverse mammal species.  

Visitors who enjoy fishing and other recreation in the Colorado River or along its banks may come to parks like the Grand Canyon simply to witness the majesty of the landscape. They may also engage in canoeing, kayaking, swimming, and other activities. Whether you would like to enjoy the natural beauty fed by the river’s flowing water or simply appreciate its important role in history, there are many ways to enjoy the Colorado River. Let’s go deeper together in learning about the critical role it has played as part of the United States landscape! 

Hoover Dam, The United States

The Colorado River and Hoover Dam have done much more than simply provide water for human consumption in cities and for farming work.

© Pavone


For thousands of years, the Colorado River has had a critical part to play in the broader ecosystem and the lives of humans living in North America.

Ancient History

Dating back to 12,000 years ago, the Colorado River was important to indigenous people living in the western part of the continent. They used the river for transportation, agricultural irrigation, and more. In the upper part of the Colorado basin, the Ute and Paiute lived alongside the river. The Hohokan people and then the Yuman lived in the lower basin area. Native people lived in this area for thousands of years. During this time, the different cultural groups engaged the Colorado River. They created sophisticated irrigation systems. Some used it for flood agricultural methods. They traveled via boat.

However, their lives and rhythms were disrupted by the Spanish exploration. This ushered in a new era of development that began in the 1500s. 

Modern History

Beginning with European exploration, surveyors started mapping the Colorado River. At first, they took an eye toward discovering the routes and territorial boundaries. They wanted to understand trade routes and use the river to travel and establish land rights. Eventually, Mormon settlers moved into Utah’s Great Basin starting in the 1840s and western settling began. Eventually, federal government surveys began in the 1870s. One of the first famous explorers of the area was named John Wesley Powell. He gained fame and celebration for his study of the river, mapping of geologic formations, and vivid descriptions of the indigenous people’s cultures. He was followed by other surveyors. Their focus would eventually land on developing the river and using it for irrigation starting around 1900.

It was during the 20th century that America’s federal government began investing in the development of the river. This included the construction of dams. The first development was in 1928 with the passing of the Boulder Canyon Project Act. This act authorized the building of what is now called the Hoover Dam. Since then, there have many other development projects. Many of these have been marked by controversy. There are also ongoing political disagreements between states about water use rights.

Today, new development projects are impacted by environmental considerations, Native claims to water rights, state reservoir management, and global climate change. Overall, understanding the history of the Colorado River is essential to interpreting the development of the western United States, modern agriculture in the region, and tourism and recreation as part of the National Parks.

Colorado River

Dating back to 12,000 years ago, the Colorado River was important to indigenous people living in the western part of the continent.

©Wisanu Boonrawd/

Activity and Commerce

The Colorado River has long been an important economic driver and transportation route. Because of that, if the river were to dry up, the impacts would be immeasurable. Timothy James, a professor of economics from Arizona State University, summarized the findings of a recent investigation into the river’s importance by saying, “The Colorado River is the lifeblood of the entire region.” The river supports over $1.4 trillion in economic activity each year and contributes to 16 million jobs across the western United States. 

Over centuries, the Colorado River allowed people to begin farming in the desert landscape in the 1800s and 1900s. Even today, the river is a source of vital water irrigated across millions of farmland – farmland which would otherwise be desert. The river is also an important source of hydroelectric power and provides water to urban centers, including Las Vegas, Los Angeles, and Phoenix.

Another important economic impact of the Colorado River is the ample opportunities it provides for recreation. Billions of dollars come from the numerous recreational activities that the river provides, both to residents of the states it crosses through and to millions of visitors who come from across the United States and the world. This article will cover the Colorado River’s importance in recreational activities later on.

Man on Boat in Arizona

Billions of dollars come from the numerous recreational activities that the river provides.



As the sixth largest river in the United States, the Colorado River is significant just because of its immense scale. This iconic river is 1,440 miles long. For its first 50 miles, the Colorado River is about 50 feet wide before growing to 200 feet wide. During the summer, the river’s peak flow exceeds 100,000 cubic feet per second! Imagine the power of a river that, in parts of the Grand Canyon, flows at an average speed of four miles per hour. 

Covering over 260,000 square miles, the Colorado River basin makes up 8% of the continental United States! As the river crosses into different states and travels its more than 1,400 miles, it covers varied terrain and changes elevation – from the Rocky Mountains’ alpine tundra to the low-lying desert of Arizona.


At its deepest, in the far reaches of the Grand Canyon, the river reaches 30 feet deep. In other places, it is only 10 feet deep. 


 The Colorado River’s headwaters begin in the Rocky Mountain National Park in Colorado and cross multiple states until it reaches its mouth in the Gulf of California. As it flows, the river crosses seven states, passing through Arizona, California, Colorado, New Mexico, Nevada, Utah, and Wyoming.

Rocky Mountain National Park Colorado

 The Colorado River’s headwaters begin in the Rocky Mountain National Park in Colorado.


Fish and Aquatic Life

The Colorado River is home to a vast assortment of fish. In the upper Colorado River basin, native fish species include Bonytail, Colorado pikeminnow, Humpback chub, and Razorback sucker. Bonytail fish are a highly endangered species that has long inhabited the river but are now extremely rare. Two species are endangered: the Humpback chub and Razorback suckers, which are also an important part of the Grand Canyon area of the Colorado River.

The Grand Canyon portion of the Colorado River alone was once home to eight species of native fish. In the Grand Canyon area, there are two families of fish: minnows (Cyprinidae) and suckers (Catostomidae). Many of these fish are found only in the Colorado River, likely due to the river system’s geographic isolation. In addition to the Humpback chub and Razorback suckers, other native fish include the Speckled dace, Flannelmouth sucker, and Bluehead sucker. These five are the only remaining native fish species of the original eight that lived in this part of the Colorado River.

However, since the Glen Canyon Dam was completed in 1963, the fish that live in this part of the Colorado River has changed to also include invasive species. These include rainbow and brown trout, which prey on native species such as the humpback chub. Anglers also go to the Colorado River hoping to catch largemouth bass, catfish, black crappie, walleye, or striped bass.

Largemouth bass on ice

Anglers also go to the Colorado River hoping to catch largemouth bass and other fish.



In addition to the fish that dwell in the river itself, the Colorado River is part of forming an important habitat for numerous animals. The wetlands and forests are vital habitats for many animals of the American West. Among these are the beavers that construct their dams in and around parts of the Colorado River. Rabbits, deer, bighorn sheep, and elk come to the riverbanks. Turtles, frogs, lizards, tortoises, toads, and geckos live in or around the water. Overhead, beautiful songbirds and raptors fly in the sky and make their homes in nearby trees. These include falcons, eagles, woodpeckers, goldfinches, alder flycatchers, and others. In other areas, you may see bears, mountain lions, foxes, coyotes, wolves, and raccoons, roaming the nearby land.

Of course, you cannot ignore the diverse snakes that also live around the Colorado River. These include gopher snakes, bullsnakes, northern water snakes, multiple species of garter snakes, and rattlesnakes. Another unique reptile to watch out for is the Gila Monster. Gila Monsters are the only venomous lizards that live in the U.S. They make their home near the Colorado River, particularly in parts of the Grand Canyon National Park!

Additionally, among the animals that make the Colorado River Basin their home are many rare or endangered species. These include the Mexican Spotted Owl and the North American River Otter.

Preserving the Colorado River is crucial to ensuring that all of these creatures, including those on the brink of extinction, can continue thriving along the river.

A rodent species, a large beaver walking over the beaver dam.

The beavers construct their dams in and around parts of the Colorado River.



The Colorado River cuts through geographically and geologically diverse terrain, coursing through billions of years of geologic history and three geologic provinces: the Rocky Mountains, the Colorado Plateau, and the Basin and Range Provinces. Over its evolution, the Colorado River basin’s story included many different geologic processes occurring over millions of years. 

Beginning in the Rocky Mountains, the mountain ranges of central Wyoming and Colorado are composed of igneous (volcanic) rock. The sources of the Colorado River begin high in the mountains, among igneous and metamorphic rock. As these sources were uplifted, erosion from rain and glaciers began cutting away the land. When the water ran downhill, the channels carved rivers and streams. As the river flows southwest, it enters into the Colorado Plateau. In this area, the Colorado River flows through sedimentary rock pocketed by igneous and metamorphic rock. In this area, you can see layers of beautiful, colorful sedimentary rock denoting the area’s history of tectonic activity and sea deposits through limestone and sandstone. Moving toward Arizona and Nevada, the Basin and Range Province shows mountain ranges and basins full of sediment. These basins are dry, flat deserts full of sand and rocky soil.

Recreational Activities

Each year, millions of people enjoy a variety of activities made possible due to the Colorado River. These sports and water activities contribute billions of dollars to the economy, provide millions of jobs, and are a vital part of tourism and entertainment in the states that the Colorado River crosses through. Whether you are a boater, birdwatcher, angler, or hiker, the Colorado River Basin is sure to offer an activity you can enjoy. Fishing, whitewater rafting, paddling, boating, backpacking, hiking, and many other activities contribute to about $26 billion in revenue each year, as people flock to America’s outdoor playground: the Colorado River area.

Grand Canyon National Park - Rafting

Traveling the Colorado River by canoe, kayak, or whitewater raft is a unique and exciting way to enjoy the natural beauty.

©Jim Mallouk/


One of the most popular activities at the Colorado River is fishing! In particular, anglers come looking to catch a “big one” in the form of largemouth bass or catfish, while bluegill, striped bass, and crappie are other popular catches. The river’s diverse ecosystem offers something for new and experienced anglers, who can fish from the river banks or try their luck on a canoe, kayak, or other boat.


Speaking of boats, traveling the Colorado River by canoe, kayak, or whitewater raft is a unique and exciting way to enjoy the natural beauty of geologic formations, nature, and wildlife. From quiet, slow-moving areas to more dramatic rapids, casual boaters and adventurers can both find something to enjoy.

Hiking and Camping

Since the Colorado River moves through so many iconic national and state parks, one of the best ways to take in the majesty of this river is by following it on land. Whether you want to hike into the Grand Canyon, travel through lush forests and fields, or camp on the river’s beaches, there are abundant opportunities to see the Colorado River’s beauty in each state it crosses. Hiking or camping near its banks also gives you the opportunity to see rare birds; wildlife like turkey, deer, elk, or bighorn sheep; and others. But stay away from some of the more dangerous creatures that live near the Colorado River! Animals like bears, coyotes, foxes, and mountain lions are also often spotted along the river’s banks. 


As one of the most important economic drivers, geographic features, and natural resources, the Colorado River is vitally important and touches millions of lives every day. However, it is also a place where you can enjoy being outdoors and marveling at the natural wonders of this world. 

The photo featured at the top of this post is ©

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About the Author

Carrie is a writer and fan of all types of plants and animals. Her apartment is home to more than dozen different houseplants and she aspires to adopt more in the near future. You can find Carrie taking long walks or reading a book under the trees in the park.

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