The geographical area served by the Arkansas Valley Audubon Society consists of that part of Colorado along the Arkansas River from its headwaters near Leadville to Holly at the Kansas border then south to New Mexico and west to the western edge of the San Luis Valley. Ours is a region of over 20,000 square miles.

This huge, sparsely populated area contains a great variety of habitat. The eastern plains are mostly semi-arid short grass prairie with the notable exception of the Arkansas River riparian corridor. The area along the New Mexican border east of Trinidad is a unique combination of mesas and high grasslands. The western third of our area is mountainous, with some of the most spectacular scenery and wildlife habitat in Colorado. The Sangre de Cristo range for example contains several 14,000-foot peaks and some of the most diverse plant life in the entire Rocky Mountain system.