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1 ) of those sex products is unknown (no records). Also, records indicate that all fish captured on 23-24 April were taken to Ouray NWR. Toney (1987) indicates that on 27 April, one ripe female and two ripe males were spawned in the field. Records show that seven females (6 ripe, 1 non-ripe) and four males (all ripe) were captured on this date. It appears that all of these fish were taken to Ouray NWR. Collection of sex products on the spawning grounds is not indicated on the field data sheet for this date. Five attempts at spawning 1-4 females with 2-7 males 26 April to 4 May, produced an estimated 118,000 eggs (Table 2). Lanigan (1987) reports that about 15,000 eggs were fertilized (12.7% fertility ?). Toney (1987) reports that fertility was 50-90%. Personal communication with Toney suggests that Lanigan's numbers may be erroneous. Eggs produced from 26 April to 1 May were incubated indoors in a Heath incubator at water temperatures of 10-110C. A problem with fungal growth developed in the incubator. On 3 May, fungus was hand cleaned from all of the incubation trays. By noon the next day, 4 May, all incubation trays were again covered with fungus. Eventually, the fungus wiped out all but a few hundred eggs (200 ?). Also, it has been shown that egg incubation temperatures may be a critical factor in the survival of razorback suckers. Studies by Toney (1974) and Marsh (1985) indicate that there is almost 100% mortality of eggs at incubation temperatures of 120C or less. Approximately 110 fry hatched from this group of eggs (55% hatch ?). The fry hatched 14-16 days after fertilization and were placed in holding tanks. Eggs produced on 4 May were incubated in an earthen pond (pond #1 ?) at water temperatures of 17-200C. Apparently a problem with fungus developed also in this group of eggs. Most or all of these eggs died, and it is not known if any fry hatched.