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<br />miles upstream from its confluence with the Green River (D. Osmundson, <br />personal communication). Wild bonytail are considered extirpated from the <br />Lower Colorado River Basin. <br />Relict populations of bonytail currently inhabit Lake.Havasu and Lake <br />Mohave in the Lower Colorado River Basin (below Lee's Ferry, AZ). A hatchery <br />broodstock was developed from specimens collected from Lake Mohave from 1974 <br />to 1989 (Wydoski 1995). Offspring from these fish are held at Dexter National <br />Fish Hatchery in Dexter, New Mexico (Meyer 1992). This broodstock and, if <br />possible, wild supplementation will provide individuals for reintroduction. <br />The latter, however, is unlikely since very few bonytail have been positively <br />identified in the past two decades from the UCRB (Valdez and Clemmer 1982; <br />Valdez 1985; Kaeding et al. 1986; USFWS 1987). Proper genetics protocol will <br />be followed in establishing a bonytail broodstock for reintroduction (Wydoski <br />1995). This protocol is discussed in the Stocking Plan, Source of fish <br />section of this plan (page 33). <br />Recent reintroduction efforts <br />In an attempt to study bonytail habitat use, movement and survivorship, <br />the Bureau of Reclamation, USFWS, UDWR and Dr. T. Modde of Utah State <br />University conducted an experimental stocking project in 1988. Over the <br />period of this study, eighty-six fish were surgically implanted with radio <br />transmitters and released into the Green River in Dinosaur National Monument. <br />Documented mortality of these fish was 74.5% but suspected to be higher. <br />Sixty-seven fish died while being held in tanks. High mortality was <br />attributed to domestication and stress (Meyer 1992). Handling stress should <br />be reduced and fitness improved to increase reintroduction effectiveness and <br />prevent further prodigious expense and effort towards bonytail recovery. This <br />1 <br />1