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One female's eggs were bad and were not utilized in the hatching trials. Mean viability for the two hatching methods was 60.7% (of 2,100,587 eggs); expected number of fry was 1,274,753. Actual number of swim-up fry was 354,000 for Y 27.7% of expected fry and 16.9% of good eggs produced. Hatching success per viability expectations was excellent but we encountered severe fry loss due to "bunching" in the square corners of the holding tanks. The fry would bunch together in piles up to two inches deep that extended outward five to six inches. lifter extended periods of time the majority of the fry in these piles would s-uffocate. All losses occurred at night when we were not around to keeo the bunches dispersed. In 1984 we will experiment with round tanks to determine th--.r suitability in preventing these type of losses. We had planned on utilzing 500,000+ fry but were restricted to the 354,000 reported above. These fry were distributed as follows: 10,000 to California Fish and Game Department; 10,000 to the Columbia National Fishery Research Field Lab, Jackson, Wyoming; 100,000 to Willow Beach NFH; and 234,000 to Dexter rearing ponds. We had anticipated planting 350,000 fry at Dexter and providing Willow Beach with 150,000 fry. Of the 234,000 fry stocked in rearing ponds we returned 160,000 advanced fry (68°0). We restocked 120,000 of the advanced fry and shipped 40,000 to Willow Beach. We returned 87,153 of the advanced fry as fingerlings for a 72% return. We moved the fingerlings to new ponds for one month and got a return of 9q.A°% (86,638), 13,362 short of the 100,000 fingerlings requested. The fish were osetagged with CWT's and hauled to Region 6 where they were olanted in selected ground water ponds and backwaters of the Colorado River near Grand Junction, Colorado. Feed conversion for Colorado squawfish were 3.90. Requests for up to 600,000 CSF fingerlings for the near future has been discussed. Consequently we are maintaining 215 mature adult CSF and 460 two-year-old future brood. The young broodfish should spawn in 1987. Bonytail chub - We carried over two female and three male adult bonytail chub from 1982. One additional male bonytail was collected from Lake Mohave in the spring, but the fish was in poor condition and died shortly after being brought to Dexter. The two adult female bonytail were spawned in mid-April utilizing carp pituitary as the egg ovulation stimulating hormone. One female gave 50,096 eggs (38% viable) and the other 35,376 (11% viable). Mean viability was 26.8% and expected fry 22,906. Twenty four two-year-old female bonytail were spawned over a four week period during May. Good quality eggs were obtained throughout the spawning trial. Mean weight of the 24 fish was 0.28 lbs (127 gm). Fecundity ranged from 1,015 to 10,384 and the mean fecundity was 4,677. Average number of eggs per pound of body weight varied from 5,075 to 29,930 with a mean of 17,280. These are pro.jected figures due to the small size of the fish (0.1 - 0.5 lbs). A total of 119,764 eggs were taken with a mean viability of 67.5%; expected number of fry was 80,840. We shipped 10,000 BTC fry to the California Fish and Game Deoartment and 28,711 to the Arizona Game and Fish Department. Arizona's fish were stocked in Lake Mohave backwaters. The additional fry were preserved as specimens.