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0 C D D b these flows on razorback sucker populations. Levees in river reaches targeted for restoration should be modified to allow fish access during the spring. Future levee construction in river reaches important to razorback sucker recovery should be discouraged. Potential reaches for experimental stocking include the 15- and 18-mile reaches of the greater Grand Valley, the Rifle to Debeque reach on the Colorado River and a 10-mile river reach on the Gunnison River near Delta (Figure 3). Consideration should be made to screen the diversion-canal int at Government Highline Diversion and Redlands Diversion Dam to prevent entrainment of stocked fish into the irrigation canals. Valdez et al. (1982) considered the Grand Valley region of the upper Colorado and Gunnison rivers to be very important habitat for razorback sucker in the early 1980's. Osmundson and Kaeding (1991) believed the '15-mile' reach of the Colorado River in the Grand Valley to be a concentration area for razorback sucker and one of the most important stretches of the upper Colorado River for this fish in the past. Historically, razorback sucker were abundant in most of the Gunnison River (Jordan 1891; Jordan and EvPrmann 1896)., but are extremely rare there now. Razorback sucker were common as recently as the 1950's based on catches made by a mink farmer in the Delta area (Wiltzius 1978). However, only one razorback sucker was collected in the 1970's (Wiltzius 1978). The last capture of a razorback sucker in the Gunnison River was documented by Holden et al. (1981). They captured four adult razorbacks between Escalante Creek (river mile 42) and river mile 54 downstream of Delta in May and June 1981. Two adult razorback sucker were collected in 1981 near the town of Parachute, Colorado (Valdez et al. 1982). A young (21.5 mm TL) sucker 21