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downstream to upstream locations may need to be considered. Annual or biannual <br />transfers of 10 or more chub from each of several locations in the lower reach to several <br />locations in the upper reach would. suffice to counter divergence within the river due to <br />genetic drift (Gillespie 1998). <br />3. To reduce the risk of genetic divergence between captive and wild populations, the <br />refuge stock at Dexter should be infused on a regular basis with chub from the Virgin <br />River, as long as removal of fish would not negatively impact the donor populations. <br />Currently, the captive stock is primarily comprised of fish from the upper portion of the <br />river. If the VRRMRP would like the refuge population to be representative of both <br />upper and lower portions of the river, chub should be randomly chosen from throughout <br />the range of the species and brought into the broodstock. We recommend the addition of <br />150-200 wild fish to the refuge population every three or four years. <br />20