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following day, 25 May, five ripe males were collected and transported to the hatchery to fertilize with the captured female. Stripping of the female yielded about a dozen, poor colored eggs which were discarded. All of these fish were released alive at RMI 254.6 on 25 May. On 31 May, one ripe female and ripe four male razorback suckers were stripped in the field. The female yielded about 7,000 eggs (5,224 eggs per Kg body weight) and was 544 mm TL. The four males ranged in size from 450-511 mm TL. These eggs were incubated indoors in a Heath incubator at water temperatures of 20-210C, 31 May to 6 June (Table 4.). Fungus did develop on some of the eggs, and these eggs were removed by hand as encountered. Eggs commenced hatching at 112 hours after fertilization, and were finished hatching by 145 hours. Hamman (1985) calculated the expected number of razorback sucker fry to hatch, for a Heath incubator at water temperatures of 20-220C, as 61% of female fecundity. Based on this, theoretically 4,270 fry should have hatched. The actual number of fry hatched at the Ouray facility was 2100, or 30% of female fecundity. The hatching fry ranged in size 5-7 mm TL. As the fry hatched, 5-6 June, they were captured by aquarium nets and placed into a separate holding tank. Water flow in the holding tank was two gpm, and temperature was 21-220C. The fry were held in the holding tank 5-10 June, at which time 1500 fry were placed into pond #3, and 600 fry were held back for feed trials. POND REARING Pond #3 began filling 25 April, and was full by 9 May. Fertilizers were added to the pond to encourage plankton blooms as a source of food for the fry. Alfalfa is an organic fertilizer and is used to "accelerate the production of zooplankton in rearing ponds, particularly in new or sterile ponds (Piper, et al., 1986)". Phosphorus, an inorganic fertilizer, is known