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<br /> <br />o <br />o <br /><-., InitiallY, excess fish from existing facilities will be the only fish available for <br />(,~ augmentation efforts. the San Juan Recovery Implementation Program has no <br />C':l hatchery facilities and broodstock of its own. Despite this current lack of <br />~ production facilities. the San Juan Recovery Implementation Program has the <br />opportunity to begin augmentation of razorback sucker at little cost to the <br />program, while still following the sequential genetic guidelines listed above. <br />Currently, three groups of excess fish are available for use: <br /> <br />1. Horsethief State Wildlife Area (Grand Junction, Colorado) arising from <br />paired matings of adults from the San Juan River arm of lake Powell and <br />Colorado River. <br /> <br />2. Ouray National Fish Hatchery (Ouray, Utah) arising from both <br />streamside spawnings and paired matings of Green River adults. <br /> <br />3. Willow Beach National Fish Hatchery (Willow Beach, Arizona) arising <br />from larval collections from lake Mohave. <br /> <br />Although the existing fish at these facilities range in size from 1 50 mm to 300 <br />mm, and are thus smaller than the optimum size, it is necessary for the San <br />Juan Recovery Implementation Program to take possession of and stock these <br />fish by fall 1997. A motion to stock these three groups of fish in the San Juan <br />River in 1997 was considered and passed by the San Juan Recovery <br />Implementation Program Biology Committee on 19 March 1997. <br /> <br />VII. Explanation of effects of the action: <br /> <br />If successful, augmentation will establish a multiple year class population of <br />razorback sucker sub-adults and adults that are largely invulnerable to predation <br />by channel catfish and other predators. The presence of adults attempting to <br />reproduce will facilitate the identification of factors currently limiting successful <br />natural recruitment. <br /> <br />Because of the screening criteria to be in place prior to stocking, it is not <br />expected that hatchery-reared razorback sucker will expose wild fish to <br />pathogens or diseases not already occurring in the wild population. <br /> <br />Based on the length of river available to the stocked and wild populations of <br />razorback sucker and the extremely low populations of wild razorback sucker in <br />the San Juan River, it is not anticipated that competition for habitat or food will <br />occur between the stocked and wild fish. Indeed, it is expected that monitoring <br />of the stocked fish may allow researchers to gather more, criticallY needed, <br />information concerning the wild population of razorback sucker. <br /> <br />The potential to affect the genetic integrity of the wild population of razorback <br />sucker in the San Juan River will be addressed by the safeguards of the <br />Genetics Management Plan and the adherence to the sequential priority of <br />stocks to be used. Razorback sucker from the Green and Colorado rivers, lake <br />Mohave, and the San Juan River arm of lake Powell (the three sources for use <br />in this augmentation effort) were studied to determine if each system contained <br /> <br />4 <br />