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<br />3 <br /> <br />Reclamation's concern with the proposed flow regime is that we believe that <br />the humpback chub larval fish production is more dependent on the hydrology <br />and environmental cues of the little Colorado River than the availability of <br />backwater habitats. Secondarily, we are concerned that the creation of stable <br />backwaters will lead to development of habitats that are also conducive to <br />non-native species that will outcompete or exclude the native fish from <br />backwater use, potentially creating a worse condition than has existed in the <br />past. Reclamation believes that this question needs to be evaluated <br />scientifically prior to implementing a flow regime that may result in the <br />opposite effect of that which is desired. <br /> <br />Rather than the flow scenario described in element la, we recommend <br />accelerated implementation of the Selective Withdrawal Structure. <br /> <br />The discussion of direct effects of implementing the MlFF Alternative in the <br />DBO acknowledges positive benefits for endangered fish. These benefits <br />include increased flood protection, increased sediment retention, reduced <br />transportation of young chubs downstream of the little Colorado River (lCR), <br />and an increase in turbidity resulting from fluctuations. Turbidity is <br />important to the young humpback chub as it provides cover from predators. The <br />DBO also recognized that the MlFF Alternative will maintain access to <br />tributaries for endangered fish. For these reasons, we do not believe the <br />action of implementing the preferred alternative as described in Enclosure 2 <br />will adversely impact critical habitat. <br /> <br />Indirect Effects <br /> <br />The discussion of indirect effects focuses on non-native fish. Reclamation is <br />concerned that steady flows may inadvertently benefit non-native fish species <br />to the detriment of endangered and other native fish species. We believe the <br />key to monitoring recommended operational changes while insuring no negative <br />effects occur lies in the implementation of a scientifically based monitoring <br />and research program as part of the Adaptive Management Program. We <br />anticipate the Service will playa vital role in recommending operational <br />modifications to benefit endangered and other native fish as a member of the <br />adaptive management program. <br /> <br />Reclamation is also concerned that the logic for identifying the effects of <br />steady flows as related to the Colorado River system in the Grand Canyon is <br />not well supported. Data coming from the GCES program and in other research <br />programs on Southwestern ecosystems consistently point to the importance of <br />disturbance in maintaining the native species assemblages. The statement that <br />the ecology of the Grand Canyon will be supported by steady flows is not <br />supported in the document or in the literature. <br /> <br />Cumulative Effects <br /> <br />The final factor considered when determining. the effects of a proposed Federal <br />action is cumulative effects. Cumulative effects are defined as those state <br />and private actions reasonably certain to occur that would have an effect on <br />the species or environment of concern. The cumulative effective on which a <br />portion of the Services's justification for a jeopardy call is based is the <br />potential for catastrophic events which may occur in the little Colorado River <br />(lCR). This has led to the Service recommending that Reclamation commit to <br />