The Colorado River doesn’t just flow through the Southwest ecosystems, it creates them. Water flowing in the Colorado River provides habitat for moose, trout, and river otters in Rocky Mountain National Park. As the river flows downstream and into the arid Southwest, it is one of the only sources of water within hundreds of miles for wildlife of all types. Four federally listed endangered species of fish still cling to existence in the river; its water and wetlands provide habitat for migrating birds from the top of the basin all the way to the bottom; and bighorn sheep, elk, mule deer, bear, and mountain lion prowl its banks all along its 1,450 mile journey.

When dams, reservoirs, and diversions drain the river, they also drain and destroy the ecosystem in and around the river. Fish are endangered due to dam construction. Wetlands are threatened because the river no longer fills them. Wildlife is threatened because their habitat and food source no longer exists. Human use of the water competes with the necessary role that the water plays in the life of fish and wildlife in the entire ecosystem. When we take water out of the river, we take it from other life forms that were using it – and that life form is sometimes destroyed because of us. Protecting the Colorado River will help protect the Southwest United States and the biological diversity its wild ecosystems contain.