With its majestic rock cliffs; its ribbon of cool water running through classic Sonoran Desert; and its cattail-filled marsh harboring rails and waterfowl, Bill Williams River National Wildlife Refuge offers a little bit of something for both wildlife and people.This 6,105-acre refuge holds one of the last stands of natural cottonwood-willow forests along the lower Colorado River, creating a unique ecosytem that provides good habitat for resident and migratory wildlife. There are few places where one can stand, look at a Saguaro cactus, a cattail stand, and a cottonwood tree together. This unique blend of upland desert, marsh, and desert riparian haitat provides for a diverse array of birds, mammals, and reptiles. This diversity of wildlife includes: the southwestern willow flycatcher, vermillion flycatcher, yellow-billed cuckoo, western tanager, Lazuli bunting, Yuma clapper rail, beaver, bobcat, mountain lion, gray fox, javelina, mule deer,desert bighorn sheep, ringtailed cat, Razorback sucker and bontail chub.

The rare riparian habitat of Bill Williams River NWR draws a variety of neotropical migratory birds - winging their way from Central and South America to their breeding grounds in the north. Bright colors from birds like the yellow warbler, vermillion flycatcher, and summer tanager flash like sparks in the desert sky as they flit across the riverbed.

The lower Colorado River region is within the ancestral boundaries of the Mojave and Chemehuevi tribes whose legacies date back many thousands of years. Descendants of these tribes still use willow stems from the refuge for traditional Native American basket weaving.