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Cibola High Levee Pond (HLP) is a man-made backwater in the historical Colorado River channel South of Blythe, CA, located on the U. S. Fish and Wildlife Service Cibola National Wildlife Refuge (link). The river originally flowed through many oxbows, meanders, and shallow, off-channel habitats. The progressive allocation of Colorado River water to agriculture and urban areas required a more efficient means of delivery of water between dams (Palo Verde Diversion Dam to the north and Imperial Dam to the south). Therefore, in the mid 1960's, the U. S. Bureau of Reclamation dredged what is now known as the "new river channel". It is a canal-like waterway with few off-channel habitats and circumvents the "old river channel". Levees were placed to prevent floodwaters from escaping, but in 1988, these levees were breached by high flows. A second levee was put in place to prevent reoccurrence. Between the original "river levee" and the new "high levee" was trapped a small section of the old river channel which is now known as Cibola HLP (see map at right). At about five surface acres, the pond was established as a native fish rearing facility in 1993 by C. O. Minckley of USFWS AZ Fisheries Resource Office, Parker, AZ. All fishes were removed from the backwater and it was subsequently stocked with razorback sucker and bonytail chub.

Though the original intent was a rearing facility for fish to be stocked elsewhere, it was later regarded as a sanctuary due to successful recruitment by both species in the absence of non-native predators. This is especially interesting because it is the first instance of a polyculture of two endangered Colorado River fishes, one of which is an opportunist (bonytail). Up to four generations of each species are estimated to have inhabited the pond. Routine monitoring of the pond has provided a wealth of valuable information on growth rates, spawning behavior, feeding habits, and survival rates, just to name a few.

Unfortunately, the pond was recently compromised by the introduction of multiple adult largemouth bass. The intruders spawned successfully and a healthy bass population now threatens the native inhabitants. Researchers observed a rapid takeover by the introduced fishes, and a second renovation will soon be scheduled to "reset" the conditions of the pond.

Cibola HLP has been an invaluable model for the future of native, imperiled fish management in the west. It is widely supported that mixing native and non-native fishes is to the detriment of the natives; therefore, separate habitats are a necessity. Plans are in place for creating multiple habitats similar to Cibola HLP throughout the region.