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% r Footnotes or Table 4: 1 This number refers to obtaining 500 fish per family lot for broodstock development in October, 1996. The weight in 1996 is based on 51 fish per pound. The number will be reduced to 250 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 and 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). One thousand (1,000) sucker fry (approximately 70 mm TL) were obtained on April 10, 1996. These fish were placed in another pond to be reared an additional growing season before they can be separated by spcies. Approximately 25 razorback suckers are expected to 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 PIT-tagged and stocked into the Middle Green River. 3/ In 1995, 200 fish from each family lot were stocked into the Middle Green River after one growing season. The number of fish to be stocked into the Middle Green River is equalized by the number of fish (200 per family lot) after the first growing season. The numbers were adjusted using the estimated survival rates. 4/ The target production of approximately 330 razorback suckers for stocking as 12-inch fish in October, 1997. The wild larvae would be captured in light traps from the Middle Green River in 1996. Approximately 1,000 wild razorback sucker larvae are required for this production based on a survival rate of 33% (Mueller 1995a). 5/ 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 N growout ponds will be identified and modified, if necessary, for FY 1997 production identified in the plan. O 6/ Sac fry will be reared in ponds at the Wahweap State Fish Hatchery through 1996 and 1997. Two thousand (2,000) bonytail will be stocked into the Upper Colorado River Basin at 6 inches TL in October, 1996 and an additional 2,000 (possibly more based on power analysis of expected recaptures) bonytail will be stocked at about 10 inches TL in October, 1997. The remaining fish will be stocked as 12 inch fish in 1998. 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. 7/ Larger (6-inch) progeny from the 1995 year class are available at the Dexter National Fish Hatchery NM. These 5- to 6-inch fish will be tested at Utah State University since bonytail would be 6 inches or longer when stocked into the Upper Basin. An additional thousand sac-fry bonytail will be used for other studies at Utah State University.