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<br />Proposed Water Year 2005-2006 Experimental Actions <br /> <br />("f' <br /> <br />" <br /> <br />13 <br /> <br />provide structure to habitat. Cover estimates for the river as a whole, but not for specific <br />SWWF sites have decreased by approximately 10% for vegetation up to the 45,000 cfs <br />stage level (Kearsley et a12004), TItis loss is associated with the prolonged drought in <br />the southwest. The scour of dead plants during the high flow may provide open patch <br />areas for establishment by new understory plant species and improve habitat in the long <br />term, The reworking of sediment may set the stage for improved SWWF habitat along <br />the river's edge by changing productivity in marshes, promoting the presence of <br />standing water associated with return channels, and exposing sandbars through <br />aggradation. <br /> <br />Non-native Fish Suppression Flows <br /> <br />SWWF do not establish nests prior to May and as such the non-native fish suppression <br />fluctuations would not interfere with their life history requirements, The flows would <br />occur following sediment reworking and would affect the vegetated areas as well as <br />beach areas, The physical effects of the fluctuations on the habitats may. include either <br />loss or accumulation of sediment along the shoreline up to the 20k stage level. The <br />reworking may expose seed banks for plant colonization below the 45k stage, Plant <br />colonization below the 20k stage will be delayed due to the unstable environment, <br />Subsequent months may have the effect on terrestrial vegetation and associated SWWF <br />habitat of increasing marsh habitat by increasing the wetted area available for marsh <br />vegetation to occupy, <br /> <br />Conclusion <br /> <br />We conclude that the Proposed Action may affect, but is not likely to adversely affect, <br />SWWF or its critical habitat. <br /> <br />Bald Eagle <br /> <br />Alternating Low Steady and Low Fluctuating Flows <br /> <br />Bald eagles are not in the project area during the period of these flows and thus will not <br />be affected by them, <br /> <br />High Experimental Flow <br /> <br />A high flow taking place in November-January would likely have little affect on feeding <br />behavior of bald eagles along the Colorado River. In the past, the presence of bald <br />eagles along the river peaks in February and coincided with trout spawning in <br />tributaries (Brown and Trosset 1989, Brown 1992). Bald eagles begin arriving in late <br />November, so that timing of a high flow in under the No Action alternative may have a <br />slightly larger affect on bald eagle foraging than would the same flow at an earlier time <br />