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<br />12 <br /> <br />GLEN CANYON DAM ADAPTIVE MANAGEMENT PROGRAM <br /> <br />Project 05 <br /> <br />I. Title: Translocation of native fishes to tributaries of the Colorado River, Grand <br />Canyon National Park and tribal lands <br /> <br />Relationship To Programs: <br />Glen Canyon Dam Adaptive Management Program Information Needs <br />M.O. 2.1 Maintain or attain humpback chub abundance and vear-class strenzth in the LCR and <br />other azzrezations at appropriate tarzet levels for viable populations and to remove ;eopardv. <br /> <br />M.O. 2.6 Maintain mannelmouth sucker. bluehead sucker and speckled dace) abundance and <br />distribution in the Colorado River ecosvstem below Glen Canvon Dam for viable populations. <br /> <br />Section 7 Consultation on Proposed Experimental Releases from Glen Canyon Dam and <br />removal of Non-native fish, December 6, 2002 <br /> <br />Conservation Measure: Approximately 300 HBC will be removed from the LCR and Colorado <br />River confluence and transported upstream to above Atomizer Falls in the LCR. <br /> <br />III. Study Background/Rationale and Hypotheses: <br />Native fishes, including the endangered humpback chub (HBC), were historically found in many <br />tributaries within Grand Canyon. However, with the exception of the Little Colorado River, <br />HBC are no longer found within these tributaries due to high predator loads. In conjunction with <br />concurrent predator removal/suppression efforts (see project I), transplanted HBC may be able <br />to exploit available habitat and remain in these tributaries until they reach larger sizes and are <br />less predator susceptible. The second objective of this project is a direct management action to <br />try and prevent the large-scale loss ofHBC in the 60-l00mm size class in the Little Colorado <br />River. Data suggest that once smaller life history stages enter the Colorado River from the Little <br />Colorado River, either through high flows or downstream drift, that a combination of cold <br />temperatures and predation significantly reduce recruitment. It appears that once HBC exceed <br />the 150-200 size range that survival significantly increases. If transplanted HBC can remain in <br />these tributaries to reach these larger size classes, they may have an increased chance of survival <br />once they enter the mainstem Colorado. In addition, since the largest remaining population is <br />within a single tributary, translocations of HBC to other tributaries would spread out the risk of a <br />single catastrophic event (such as a chemical spill upstream) that could significantly impact the <br />LCR population. <br /> <br />This project proposes to start with a translocation within the Little Colorado River in July 2003 <br />and move approximately 300 50-100mm HBC above Chute Falls. In addition to a conservation <br />action named in the December 2002 BO, this action addresses the Recovery Goal factor titled <br />Other Natural or Manmade Factors. The Chute Falls translocation project is a precursor to other <br />actions in other tributaries and is intended to expand the demographic range of HBC within the <br />LCR. <br /> <br />IV. Study Goals, Objectives, End Product: <br /> <br />00906 <br /> <br /> <br />Created on 5/6/2003 5:41 PM <br />