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<br />180 <br /> <br />VALDEZ AND MUTH <br /> <br />contaminants. Historic river habitat is being made <br />accessible by building fish passages around dams and <br />diversions, enabling endangered and other native <br />fish to migrate up and downstream. A 107-m selec- <br />tive fish passage was built at the Redlands Diversion <br />Dam on the lower Gunnison River in 1996, giving <br />endangered and native fishes access to 92 km of his- <br />toric habitat. The fish passage is operated annually <br />by the USFWS, and as of 2004, 67 Colorado <br />pikeminnow, 9 razorback sucker, 1 bonytail, and <br />more than 62,000 other native fish had passed <br />through the facility, and thousands of nonnative fish <br />had been selectively removed. <br />Fish passage is also being reinstated for the first <br />time in nearly a century to 90 km of historic habi- <br />tat in the upper Colorado River above Grand Junc- <br />tion, Colorado, with modification of three diver- <br />sion dams. The Grand Valley Irrigation Company <br />(GVIC) Diversion Dam was modified for fish pas- <br />sage in January 1998. In 2005, a 4-m wide notch <br />was cut in the concrete crest of the Grand Valley <br />Project Diversion Dam to facilitate construction of <br />a 113-m long selective fish passage. The UCRRP <br />funded the $4.5 million construction project, <br />which is a cooperative effort of the Grand Valley <br />Water Users Association, UCRRP, BOR, and <br />USFWS. Construction of fish passage at the inter- <br />vening Price-Stubb Diversion Dam is scheduled for <br />the near future. <br />Canals and water outtakes are also being screened <br />to minimize entrainment and loss of fish from the <br />river. A fish screen was installed at the head of the <br />GVIC canal in 2002 to prevent fish entrainment and <br />similar screens are being constructed in 2005 at the <br />Grand Valley Project and Redlands canals. Design of <br />a fish screen for the T usher Wash diversion canal on <br />the Green River in eastern Utah is completed and <br />construction is scheduled for the near future. <br />Floodplains are being made accessible to all life <br />stages of endangered fish by breaching or removing <br />natural or man-made levees on property leased by, <br />or under agreement with, the UCRRP. From 1992 <br />through 2002, the UCRRP inventoried floodplains <br />in the upper basin (Valdez and Nelson 2004, 2005) <br />and acquired 13 private property sites totaling 440 <br />ha (Nelson and Soker 2002). An additional ease- <br />ment on 184 ha (134 ha of floodplain) was acquired <br /> <br />in 2003 for Thunder Ranch on the Green River, <br />the first major floodplain downstream of the known <br />spawning bar of razorback sucker. Four floodplain <br />sites on the upper Colorado River have been restored, <br />perpetual easements have been acquired on four <br />other properties (32 ha), and two properties have <br />been acquired in fee (69 ha). Perpetual easements <br />have also been acquired on three properties (80 ha) <br />on the Gunnison River. <br />Floodplains acquired by the UCRRP have been <br />evaluated to ensure suitable water quality for the <br />endangered fish. High levels of selenium have been <br />found in some floodplains and remediation has been <br />implemented to reduce these levels. A joint effort of <br />the UDWR, BOR, and USFWS at the Stewart Lake <br />Waterfowl Management Area near Jensen, Utah, <br />involves inlet and outlet channels with water con- <br />trol gates, drainage tiles, and water management, <br />all designed to reduce concentrations of selenium <br />and detrimental effects on fish and wildlife. Studies <br />are ongoing to evaluate fish use, growth, and sur- <br />vival in these floodplains. <br />Nonnative species and sportfishing.-Negative <br />interactions with certain warmwater nonnative fish <br />species have contributed to declines in endangered <br />and other native fish populations. For several years, <br />the UCRRP has worked cooperatively with state and <br />federal partners to identifY management actions to <br />minimize the threat of nonnative fish to survival of <br />endangered fish. In spring 2004, UCRRP partners <br />adopted a policy to identifY and implement nonna- <br />tive fish management actions needed to recover the <br />endangered fishes. The policy was a landmark event <br />demonstrating that these diverse organizations rec- <br />ognize that management of nonnative fish is essential <br />to achieve and sustain recovery of the endangered <br />fishes. The policy also recognizes the dual responsi- <br />bilities of state and federal fish and wildlife agencies <br />to conserve listed and other native fish species while <br />providing recreational sportfishing opportunities. <br />The UCRRP has implemented several actions <br />to reduce threats from nonnative fishes, including <br />mechanical removal, screening off-river impound- <br />ments to prevent escapement of fish to the river, <br />chemical removal of nonnative fISh in small off-river <br />impoundments, implementation of nonnative fish <br />stocking procedures, and changes in state bag and <br />