Investigations into the early life histories of the razorback sucker and bonytail in Cibola High Levee Pond, Arizona - Fish Survey data

Razorback sucker and bonytail were once common throughout the Colorado River Basin. Both are now federally listed as endangered. Efforts to help the fish began with the creation of the Colorado River Fishery Project in 1976. Since then wild populations continued to decline and in some cases have totally disappeared. Today less than 5,000 wild razorback sucker exist and wild bonytail may be gone. Cibola High Levee Pond (CHLP), historically part of the Colorado River channel, was initially set aside as a grow-out facility for bonytail and razorback sucker. The pond is located in the Cibola National Wildlife Refuge, approximately 5 miles south of Palo Verde, California. CHLP was chemically renovated in 1993. Nearly 58,400 small bonytail and 14,000 razorback sucker were stocked between 1993 and 1996 by Fish and Wildlife Service (FWS). Fish growth was monitored and as fish reached 30 cm in length they were removed, PIT tagged and stocked elsewhere. In December 1998, biologists discovered both species had successfully produced thousands of young. This level of “natural” reproduction is simply unprecedented anywhere in the basin. The fact that one, let-alone both species had produced young stimulated interest into the mechanisms and factors that led to their survival. Fish removal was suspended in December 1998 in hopes of studying this phenomenon. The Cibola Pond can provide researchers the first opportunity to study the early life history of both species in a seminatural setting and examine community composition, fish densities, standing crop, age frequencies, spawning ecology and behavior, and recruitment strategies. These data represent measurements recorded during fish surveys, using trammel nets and light traps. Captured fish were measured, sexed, and tagged.