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<br />" <br /> <br />Proposed Water Year 2005-2006 Experimental Actions <br /> <br />01816 <br /> <br />7 <br /> <br />reworked and aquatic macrophytes likely scoured. The resulting coarsened substrate <br />should favor recolonization by algae rather than macrophytes (Yard and Blinn 2001) that <br />support a different benthic association like the filamentous green alga Cladophora, <br />diatoms, and the amphipod Cammarus, The terrestrial inputs associated with the <br />increased discharge would provide a pulse of organic material that would be <br />incorporated into sediment deposition and carbon cycling tIuoughout the system, <br />Increased drift should follow during the recovery periods, Removal of algal overgrowth <br />may help facilitate new algal photosynthesis and an increase in gross productivity, Algal <br />biomass recovery rates appear to be rapid following these large flow perturbations if <br />algal basal holdfast structures are retained, <br /> <br />Terrestrial vegetation that is a host for invertebrates will be buried or scoured, but will <br />recover and may respond by increasing vegetative productivity as a result of increased <br />nutrient delivery. Increase vegetative productivity will increase host availability for <br />terrestrial ,invertebrates that contribute to aquatic and terrestrial food base resources in <br />the spring and summer months (Yard et a12004; M, Yard unpublished data). <br /> <br />Non-native Fish Suppression Flows <br /> <br />Proposed Action increased fluctuations likely will produce increased drift relative to No <br />Action fluctuations, but they also will likely increase turbidity in the mainstream below <br />the Paria River confluence. Increased turbidity may affect feeding behavior and food <br />availability of some fish species. It also may serve to interfere with sight-feeding <br />predators on native fish. Shoreline vegetation that serves as host plants may be delayed <br />in their development under this flow regime, but the increase in stage also could <br />increase the area occupied by marsh or wetland plant species, <br /> <br />Kanab Ambersnail <br /> <br />Alternating Low Steady and Low Fluctuating Flows <br /> <br />These flows occur at stages below the lower lin1it of Kanab ambersnail (KAS) habitat <br /> <br />and are expected to have no effect. <br /> <br />High Experimental Flow <br /> <br />There is expected to be no measurable difference in effect or in recovery between a high <br />experimental flow in November-December or January. Habitat utilized by KAS <br />normally has limited growth tIuough the fall and early winter season and begins new <br />growth in mid-February depending on climatic variables, KAS habitat as of August <br />2004 below 45,000 cfs waS 119,40 m' (K. Kohl, personal communication). Values for <br />habitat available in March 1996 prior to the BHBF were determined to be 120 m'. <br />Therefore, primary habitat that is estimated to be taken without mitigation should be <br />