The system of impoundments, channels, marshes, and backwaters extending form Imperial Dam to Fisher's Landing (below Martinez Lake).

Ornithological Summary

Ornithological Summary: Supports substantial populations of Yuma Clapper Rail and California Black Rail. High quality marsh habitat supports other wetland bird populations, such as Virginia Rail, Sora, Least Bittern, and American Bittern. Also, supports a large wintering population of American Coots (>2000 individuals). The site is part of a major migratory corridor, providing habitat for migrating neotropical birds, including Southwestern Willow Flycatcher and Western Yellow-billed Cuckoo. The site provides foraging habitat for herons and egrets.

Conservation Issues

Most riparian habitats have been overgrown by tamarisk and some areas by phragmites, but no management actions are presently being taken. Dredging would be a threat to marsh habitat if implemented (no pending proposals). Increasing selenium levels along the lower Colorado River poses a threat to avian populations.


Owned and managed jointly by the Bureau of Land Management (BLM) and the US Bureau of Reclamation (USBoR).


Marsh, open water, and riparian habitat. Most riparian habitats have been overgrown by tamarisk and some areas by phragmites.

Land Use

Land use is primarily recreation (fishing, hunting, and boating), and secondarily wildlife/nature conservation. Imperial Dam is operated with the primary objective of providing water to the All American and Gila Gravity Main canals.

Protected Areas:
None. Open to hunting.

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