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<br />002749 <br /> <br />facility, at its current capacity, can handle. Fish held at too high a density are more vulnerable when <br />exposed to pathogens. Losses due to disease and stress can be expected. <br /> <br />Between 1990 and 1994, adult razorback sucker from Upper Colorado River, Etter Pond in the <br />Upper Colorado River, Colorado River ann of Lake Powell, and San Juan River ann of Lake Powell <br />were captured and placed in ponds at Horsethieffor development of brood stock. Because there were <br />too few remaining in the wild to develop a broodstock from the Upper Colorado River, the consensus <br />of the Genetics Panel and Upper Basin biologists was that the broodstock should be developed from <br />a mixed stock. Starting in 1994, a spawning matrix was constructed consisting of 10 females and 13 <br />males, which includes five first generation male progeny from the San Juan River Ann of Lake <br />Powell. A total of34 family lots were spawned in 1994, 1995, and 1996 using this matrix with a <br />current population of approximately 200 fish per lot Only 8 females and II males included in this <br />original brood stock matrix are still alive. <br /> <br />Summary: The following table illustrates the current location of the primary and backup refuge <br />populations, if any, and the number oflots being held for each of the presumptive genetic stocks. <br /> <br /> REFUGIA BROODSTOCK <br />S pedes Presumptive stocks Primary Backup Primary Backup <br /> (# offamily lots) <br />Razorback sucker Green River Ouray -None- 4 0 <br /> Colorado River Horsethief -None- 34 0 <br />Bony tail chub Upper Basin Dexter Horsethief 2 4 <br />Humpback chub Yampa River -None- -None- 0 0 <br /> Desolation-Gray Canyons -None- -None- 0 0 <br /> Black Rocks Canyon -None- Horsethief 0 15 fish <br /> Westwater Canyon -None- -None- 0 0 <br /> Cataract Canyon -None- -None- 0 0 <br />Colorado squawjish Yampa River -None- -None- 0 0 <br /> Desolation-Gray Canyons -None- -None- 0 0 <br /> Gunnison River -None- -None- 0 0 <br /> Upper Colorado River Dexter Horsethief 3 17 <br /> <br />Ouray - Ouray Endangered Fish Culture Experiment Station. Utah <br />Horsethief - Horsethief State Wildlife Area and Grand Valley Endangered Fish Facility, Colorado <br />Dexter - Dexter National Fish Hatchery, New Mexico <br /> <br />The draft 1997 Propagation Operation Plan has proposed Ouray as the primary refuge for <br />presumptive stocks of all four species in the Green River subbasin. Similarly, Horsethief has been <br />proposed as the primary refuge for presumptive stocks of all four species in the Upper Colorado <br />River subbasin. Backup refuges for all four species would still be needed. <br /> <br />Genetic Management <br /> <br />To ensure genetic diversity is maintained during stocking, the Recovery Program initiated three <br />genetic surveys including (I) genetic survey of!:.iiill complex (bonytail, humpback, and roundtail <br /> <br />v <br />