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Footnotes for Table 4: 1/ This number refers to 250 fish per family lot in October, 1996. The weight in 1995 is based on 51 fish per pound. The number will be reduced to 200 fish per family lot in 1997 by attrition. The average weight of these fish is expected to be about 0.5 pound per fish. The fish identified for developing broodstock for the Upper Colorado River is to increase the numbers in family lots that exhibited high mortality in 1995. 21 These are the surviving fish that were collected as wild larvae from the Middle Green River in 1995. These are the from the 6,000 wild larvae in Table 2 that are described in footnote 9 of Table 2. Survival rates of 25% from larvae through the first year were based on Scholz et al. (1993) and 33% from advanced larvae to the end of the first year of life were based on Mueller (1995). An estimate of 1,500 fish should remain at the end of the 1996 growing season. The expected number of fish to survive to the end of the growing season is 495 fish. Based on the proportion of razorback suckers from previous larval sampling approximately 25 razorback suckers will survive until September, 1996. The relatedness of surviving fish to the wild fish being used as broodstock will be determined through DNA fingerprinting. Some of these fish will be used for broodstock development and the remaining fish will be stocked in the Middle Green River. 0 3/ Space limitations in 1996 govern the target production of approximately 999 razorback suckers for stocking as 12- inch fish in October, 1996. These fish would be produced from wild larvae captured in light traps from the Middle Green River in 1996. Approximately 3,000 razorback sucker larvae would be required based on a survival rate of 33% (Mueller 1993). If sufficient wild razorback sucker larvae are not captured in light traps during 1996, then 170 per family lot from the 6 family lots produced in 1996 would be substituted (1,000). If these captive-reared fish are used, they will be treated with morpholine or alcohol and treated as part of the chemoreception study. 4/ This is the number of fish identified in the stocking plan for the Gunnison River (Upper Colorado Recovery Program 1995b). An identical number of fish was identified for experimental stocking of the Upper Colorado River in this plan but this is not realistic for FY 1996 because of space limitations. Additional growout ponds will be identified and modified, if necessary, for FY 1997 production identified in the plan. 5/ Larger progeny from the 1995 year class are available at the Dexter National Fish Hatchery NM. These 5- to 6-inch fish should be 8 to 8.5 inches total length in October, 1996. An additional thousand fish will be produced from sac-fry and should reach a total length of 5 to 6 inches by October, 1996. These fish will be stocked in one location where monitoring effort will be confined to a smaller river reach and will allow for a better evaluation of the two size groups of fish. All fish will be PIT-tagged prior to stocking. The fish will not be maintained as family lots since the original broodstock was derived from only a few bonytail.