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44 on the issue of introduced fish impacts upon native fishes. These views are paraphrased below; -Introduced species impacts are well down the list for the Colorado River endangered fishes. -1. Construction of mainstem dams 2. Interruption of seasonal flow regime 3. Introduced fishes 4. Water quality degradation 5. Disease and parasites -Industrialization including agriculture in Utah has created habitats that are more ideally suited to IroUgh" fish or introduced species in a lot of instances. -Introduced fishes represent very little impact compared to the loss of habitat -Habitat loss or change is the primary reason that the other impacts exist -The impact of habitat alteration, flow depletion, and impaired water quality pose as much or greater threats to native fishes than (effects of) introduced fishes. The threat of water depletion will be much greater in the future in view of water deficits projected for New Mexi,co and neighboring states. -Impacts on habitat are the primary reasons for the decline of most threatened and endangered fishes (including dams, grazing, water quality, pollution). -Introduced fishes have almost equal impact as flow alteration, flow depletion, and habitat degradation. -The endangered fish species would have suffered if no other species had, been introduced to the river, primarily because of flow alterations that have negatively affected habitat quality~ and dams that have blocked migration and gene flow among reaches. However, effects from introduced fishes have made survival of endangered fish all the more difficult The relative importance of introduced fishes probably differs among endangered fish species. -Synergism of habitat degradation combined with nonnative species establishment exacts the greatest toll on native wildlife. Natural hydrographs, intact watersheds, elimination of point and non-point pollution sources, and halting of channelization and diversion management practices will ultimately be responsible for counter-acting nonnative species domination. -Most of these activities negatively affect the natives and in many cases positively affect