Wilderness Landscape & Natural Heritage
Imperial National Wildlife Refuge spans approximately 25,000 acres along the Colorado River at the California-Arizona border. This refuge safeguards a rare desert wetland ecosystem in the arid Sonoran Desert landscape, featuring riverside cottonwood and willow forests, backwater sloughs, and expansive marshes. Established in 1939, the refuge provides critical habitat for over 270 species of birds including many migratory waterfowl and endangered species such as the southwestern willow flycatcher and Yuma clapper rail. The refuge's landscape is characterized by broad floodplains and tidal inundations from the river, which support a diverse aquatic and terrestrial community. Wildlife enthusiasts visit the refuge primarily for birdwatching, with opportunities to see species like great blue herons, herons, egrets, and bald eagles. Beyond wildlife observation, the refuge allows fishing and boating along designated river corridors, especially in the lower Colorado River. A network of unpaved roads and trails offers limited hiking and wildlife viewing, though the refuge emphasizes preservation and low-impact recreation to protect sensitive habitats. The refuge is a critical natural area buffering the river's edge from ongoing development and water management pressures, helping maintain the ecological health of this desert river corridor. Visitors appreciate the remote and quiet atmosphere that contrasts sharply with the surrounding desert landscape, providing a glimpse into an increasingly rare riparian habitat in the Southwest.
