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_ Evaluation of the genetic identity of Colorado squawfish in the -_ San Juan River and throughout the Upper Colorado River Basin should be - completed. Identifiable stocks should be maintained in hatchery ~ facilities to ensure propagation in case natural production fails. Individual stocks should be studied to gain an understanding of their stock-recruitment relationships, reproductive rates and factors af- fecting reproduction, mortality and- growth. Management may best be directed towards individual stocks. ~ The San Juan River may be a suitable site for supplemental stocking experiments with Colorado squawfish. Several tasks should be completed prior to initiating stockings. The evaluation of stocks should be completed before supplemental stocking experiments. If a San Juan stock of Colorado squawfish is identifiable, reintroduced fish should be propagated from that stock. Further habitat inventory ~ should be completed, especially during a lower water year than that of 1986-1987. The need for preparation or restoration of a stocking site should be evaluated. Stocking and monitoring plans need to be devel- oped. Release of young life stages of Colorado squawfish would be best in the braided channel area of the San Juan River versus the canyon area. Backwater habitats are more prevalent in the braided ~ channel area. Also, the relative abundance of channel catfish, a potential predator, is lower in the braided channel area than in the canyon area. Razorback sucker in the Upper Colorado River Basin appear to be _ in a perilous situation. The San Juan River should be surveyed fur- ~ they for razorback sucker. Documentation .of razorback sucker in the San Juan River would be significant., in light of their rarity in the Upper Colorado River Basin. During 1988, off-stream impoundments with direct connection to the river should be located and sampled. Spring (April and May) electrofishing has been effective in capturing razor- back sucker in spawning condition in the Upper Green River (Tyus et ~ al. 1987). This technique should be used in the San Juan River in 1988 to attempt to locate razorback sucker. Spring electrofishing for razorback sucker should be conducted in the braided channel area of the San Juan River. Emphasis should be directed towards the Bluff, Utah area of the river because of previous documentation of razorback sucker in that area (BLM 1981). Electrofishing should begin no later ~ than mid-March, since the razorback sucker collected by BOR in late March 1987 in the San Juan Arm of Lake Powell were reproductively ripe. Monitoring of razorback sucker in the San Juan Arm of Lake Powell should continue. During March and April 1988, netting opera- tions should be conducted in the vicinity of Piute Farms Marina where razorback sucker were collected in 1987. ~ Sampling of backwaters in 1987 indicated no successful repro- duction by razorback sucker in the San Juan River, Utah. In the Upper - Green River, there appears to be no recruitment of razorback sucker (Tyus et al. 1987). Unfortunately, little is known of razorback - sucker life history requirements, and such data is difficult to - 45 -