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<br />Canyon since the emplacement of Glen Canyon Dam, and that proactive management <br />actions may need to be undertaken to reverse this decline. <br /> <br /> <br />Figure 1. Early photograph of humpback chub taken on the mainstem Colorado River, <br />a short distance upriver from Bright Angel Creek. Photograph from Grand Canyon <br />Archive, Rust Collection. <br /> <br />Reasonable and prudent management actions expected to benefit the humpback chub <br />in Grand Canyon were included in the Final Biological Opinion on the Operation of Glen <br />Canyon Dam (USFWS 1994, USBR 1995). Primary among these was the attainment of <br />riverine conditions that support all life stages of endangered and native fish species <br />(Le., primarily achievement of optimal flow and temperature regimes). Other elements <br />included the development of a management plan for the LCR, and establishing a <br />second population of spawning humpback chub downstream of Glen Canyon Dam <br />(USFWS 1994, USBR 1995). To date, the Colorado River in Grand Canyon remains a <br />cold, hypolimnetically-derived, fluctuating flow environment that is not supportive of all <br />life stages of native fish. <br /> <br />Three actions that have been proposed for humpback chub are: 1) development of a <br />captive brood stock (USFWS 1990), 2) supplemental stocking of wild fish from the LCR, <br />and 3) translocation of fish to upstream reaches of the LCR or to other tributaries. We <br />here evaluate the feasibility of each of these potential actions. <br /> <br />9 <br />