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technique. Mean viability for the two hatching methods was 60.7%. As with razorback'suckers, Marsh and Pisano (in press) determined that the optimum hatching temperature for Colorado squawfish was near 700F. Heated well water flows through the Heaths at three gpm and through the jars at one to two gpm, depending on the number of eggs in the jar. Colorado squawfish eggs also hatch between 96 and 144 hours with peak hatching at about 120 hours. Hatching success per viability expectations was excellent but we encountered severe fry loss due to "bunching" in the square corners of the holding tanks. Prior to swimup the fry would bunch together in piles up to two inches deep that extended outward five or six inches. If not dispersed the majority of the fry in these piles would suffocate; this occurred at night when the fry were unattended. Following swimup the fry are stocked in rearing ponds. We have stocked fry at rates varying from 25,000 to 80,000 per surface acre; as with razorback sucker fry, Colorado squawfish fry stocking rates have not been finalized. In 1983 we spawned 26 Colorado squawfish females; 25 domestic brood (Toney, 1974) and one wild brood. Fecundity of the domestic brood fish (mean wt = 3.09 lbs) ranged from 57,766 to 113,341 with a mean of 77,436. The wild female (9.6 lbs) produced 242,981 eggs. The average number of eggs per pound of body weight was 25,241 for the domestic fish and 25,310 for the wild fish. A total of 2,178,883 eggs were taken from the 26 fish spawned. We stocked 234,000 fry in rearing ponds and returned 160,000 advanced fry (68%). We stocked 120,000 advanced fry and harvested 87,153 three-inch fingerlings for a 72% return. Feed conversion for Colorado squawfish was 3.90. The fingerlings were nosetagged with coded wire tags and stocked in selected ground- water ponds and backwaters of the Colorado River near Grand Junction, Colorado.