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I I I I I I I I I I I I I I I I I I I backwaters and may provide a better understanding of how flow and stage affect backwater habitat quality and use by young pikeminnow. Recommended Priorities for Geomorphology Research in Endangered Fish Habitats. of the Upper Colorado River Basin Kirk E. LaGory, John W. Hayse, and David Tomasko Environmental Assessment Division. Argonne National Laboratory. Argonne. Illinois We developed and implemented an approach to prioritize river reaches and habitats for geomorphic research in the Upper Colorado River Basin. Recommended priorities are being used by the Recovery Program as it develops a comprehensive research and monitoring program for endangered fish habitats. A scoring system was used to represent the relative importance of(l) existing (or potential) reach use for species and life stages; (2) habitat use for species and life stages; (3) habitat occurrence within planfonn type; and (4) dependencies among habitat characteristics and hydrologic and geomorphic parameters. Scores also were assigned to life stages and species on the basis of sensitivity to environmental variability and population status, respectively. Two workshops involving Upper Basin researchers were held in December 2002 and February 2003 to gather input and assign scores to attributes. A linked-matrix approach was used to combine scores and develop overall (all species combined) and species-specific priorities based on these attributes. Overall priority habitats identified included (1) connected backwaters and side channels in the middle and lower Green River and lower portions of the upper Colorado River; (2) flooded bottomlands in the middle Green, Colorado (near the confluence with the Gunnison), and lower Gunnison Rivers; and (3) spawning bar complexes in the middle Green, Colorado, and Gunnison Rivers. Cibola High Levee Pond: Annual Report 2003 Mueller, Gordon I, Jeanette Carpenter I , Paul Marsh2, Chuck Minckley I USGS; 1 Arizona State University: J USFWS Bonytail and razorback sucker have once again spawned and produced young at Cibola High Levee Pond (CHLP), Arizona-California. Underwater videography during spawning showed both species fed aggressively on their own eggs. Videos also recorded concentrations (average 0.89 to 3.66 animals/m2) of bullfrog (Rana catesbeiana) tadpoles and red swamp crayfish (ProcambanlS clarkii) which in subsequent tank tests illustrated they both fed on razorback eggs and larvae. Telemetry studies revealed that adult bonytail were strictly nocturnal, having a fidelity to specific bank cavities during daylight hours. All life stages exhibited schooling behavior. Predator/prey tank experiments revealed that most nonnative young fed on razorback larvae and fry. Literature suggests that at current densities, tadpoles have the potential to consume nearly a million tish lar\'ae per day. Crayfish were also an effective predator of 19