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<br />I requires that bonytail life-history be determined and integrated into <br />reintroduction efforts. <br />Of the bonytail that survived with radio transmitters, Chart and Cranney <br />(1993) were able to conduct a telemetry monitoring study of movement and <br />habitat utilization (see Life history: Habitat). However, this study took <br />place before seasonality of flows was incorporated into operations of Flaming <br />Gorge Dam. Since seasonal flow changes may be important ecological cues for <br />bonytail, the stocking efforts in 1988 may have been implemented under <br />suboptimal flow conditions. Since 1992, releases from Flaming Gorge Dam <br />simulate a more natural annual hydrograph to benefit native fish. <br />Consequently, future reintroduction efforts in the Green River may be more <br />effective because of a more natural riverine environment. <br />Life History <br />Habitat <br />Historical records indicate bonytail resided in open, mainstem sections <br />of the Colorado and Green rivers, whereas roundtail chub tend to occupy <br />reaches closer to headwaters and humpback chub in deep water areas (Miller <br />1946; Banks 1964; Behnke and Benson 1980; Hickman 1983). In contrast, some <br />recent accounts of Gila distribution suggest bonytail were sympatric with <br />humpback chub in canyon reaches, and roundtail chub are now more ubiquitous <br />throughout the upper basin (Valdez and Clemmer 1982; Dowling and DeMarais <br />1993). However, current distribution is confounded by rare observations; the <br />locale of rare captures may represent refugia rather than preferred habitat. <br />The bonytail's more specialized morphological features, such as the <br />i narrow, elongate caudal peduncle, falcate fins, raised nuchal hump and <br />1 • 10 <br />