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<br />Horsethief Ponds were put into operation in 1992 to maintain secure propagation facilities <br />with adequate equipment and personnel for captive propagation of endangered species as <br />necessary, for the Recovery Program in the upper Colorado River Basin. <br /> <br />IV. Study Schedule: 1998 <br /> <br />V. Relationship to RIPRAP: General Recovery Program Support Action Plan <br /> <br />IV.A. Genetic Management <br />IV.A.I. Augment razorback sucker <br />IV.AA. Secure and manage genetic stocks in refugia <br />IV.C. Operate and maintain facilities <br /> <br />VI. Accomplishment of FY 98 Tasks and Deliverables, Discussion of Initial Findings and <br />Shortcomings: <br /> <br />As a result of poor hatching success in 1997, steps were taken to insure optimal conditions <br />for the 1998 year class in the hatchery. Water quality parameters (temperature, pH, <br />alkalinity...) at Horsethiefwere measured and were mimicked when possible at the hatchery. <br />The feeding rate for the 1997 year class razorbacks remaining in the hatchery was reduced <br />to insure low ammonia and nitrite levels in the water. <br /> <br />In May of 1998, razorback broodstock from Horsethief Ponds were spawned and the eggs <br />were transferred to the 24 Road Hatchery. A total of 14 family lots of fish hatched. <br />Hatching success varied from 0% to 90%. Over 29,000 fish were hatched from the 14 lots, <br />a dramatic improvement over 1997 (hatching success of 0% to 20%, 604 fish representing <br />four family lots). After hatching, the larvae were exposed to morpho line for future <br />chemoreception studies. <br /> <br />In September 1998,6000 50mm fish, from one 1998 family lot were stocked into Clymer's <br />Pond for grow-out and eventual stocking. <br /> <br />By August 1998, all razorbacks from the 1997 year class were PIT tagged. On June 23 1998, <br />231 razorbacks (representing 3 family lots) were stocked into the Gunnison River at Delta <br />Colorado. On August 271998, 30 razorbacks (representing three family lots) were transferred <br />to Horsethief for future use as brood stock. On September I 1998, 246 razorbacks <br />(representing three family lots) were stocked into the Gunnison River at Delta. Forty seven <br />1997 year class razorback (representing four family lots) remain llnhe hatchery as future <br />broodstock. <br /> <br />As of November I, 1998, over 23,000 razorback suckers (representing 18 family lots, four <br />1997 lots held as broodstock, and 14 1998 lots) are being reared at the 24 Rd. Hatchery. <br />Some will be kept at the hatchery or at Horsethief for future use as broodstock. After <br />broodstock requirements are met, fish will be stocked into either the Gunnison or San Juan <br />rivers in 1999. <br /> <br />29u-2 <br />