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Razorback sucker - A total of 55 wild RBS females were spawned utilizing chorionic gonadotropin to induce egg ovulation; 46 of them (83.6%) soawned successfully. The 46 fish produced 5,728,025 eggs with-an averaqe fecundity of 124,522. At 70OF RBS eggs begin hatching at about 96 hours and continue through 144 hours; peak hatching occurs on the fifth day at about 120 hours. Egg viability at 72 hours averaged 75.1% with an expected hatch of 4,300,2F5 fry. Actual swim-up fry numbered 2,915,761 for 68.1% of expected fry and 50.9% of eggs produced. These figures represent a substantial improvement over 1982 when females produced an average 103,746 eggs, egg viability was 30.5% and swim-up fry constituted 22.5% of the eggs taken. Information gleaned from the 1982 spawning season (particularly water temperature and egg and fry handling) was very beneficial in increasing egg viability and development and fry survival this year. Additionally, after being held on the station for a year, most of the broodstock were in a superior condition re- sulting in production of better quality sexual products. Of the 2,915,761 swim-up fry produced, 376,213 were stocked in hatchery production ponds and 2,539,548 were hauled to Arizona where they were planted in the Salt River, Cherry Creek and Coon Creek. Fry in one production pond (94,555 fish) were all lost early in the production season. Reasons for the loss could not be determined. The remaining fry (281,658 fish) produced 159,367 advanced fry for a 56.6% return. We stocked 158,367 advanced fry and returned 136,419 three inch fingerlings (86.1%). These fish were nosetagged with stainless steel coded wire tags (CWT'S); 53,845 were restocked to meet fall commitments and 82,487 (620 lbs) were planted in the Gila and Verde Rivers. We got a 91.8% return (49,433 fish; 2,440 lbs) on the restocked three inch fingerlings. We lost 5,900 of these fish (292 lbs) shortly after leaving on a distribution trip but the remaining fish were planted in the Gila and Verde `--? Rivers. Feed conversion for razorbacks was 2.03. In addition to the distribution mentioned above, 1,000 advanced RBS fry were shipped to the California Fish and Game Department and 31 adult and 20 yearling RBS were planted in the Salt River. A list of fish distributions is presented in Table 2. We are maintaining approximately 350 two-year-old future broodfish which should come into production in 1984. Nearly all males were rioe and flowing milt this year and a couple of females were releasing a few egqs during the summer. These fish should greatly enhance our production capability next year. Colorado squawfish - A total of 26 Colorado squawfish females were spawned in late May utilizing carp pituitary to induce egg ovulation; their mean weight was 3.3 lbs. Fecundtity of the domestic broodfish ranged from 57,766 to '13,341 with a mean of 77,436. One wild female weighing 9.6 lbs produced 2;2,981 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 taken for an overall mean fecundity of 83,803. Eggs were hatched both in -Heath incubators and jars. Egg viability averaged 59% in the Heaths and 66% in the ,jars. Viability percentages were more closely related to egg Quality than to',,atching technique but we have determined that Jar hatching of Colorado squaw- fish is possible. By utilizing the iar method, a far greater number of eggs can be handled in less space than required for Heaths.