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<br />12 <br /> <br />Fine-Sediment Habitats <br /> <br />Fine-Sediment Storage Monitoring: Individual sand bar data collected from 1990 <br />through fall 2001, show that sand bars in the actively fluctuating zone (8,000 to 25,000 cfs), and <br />above the 25,000 cfs stage within Marble Canyon (river miles 0-61) have continued to decline <br />since 1990, despite bar restoration gains achieved by the Beach/Habitat-Building Flow test of <br />1996, and peak power-plant test flows released in November 1997 and May and September <br />2000, Although high-elevation sand bars (above 25,000 cfs) below river mile 61 (Grand <br />Canyon) appear to be in somewhat better condition in 2000 versus 1990, than bars in Marble <br />Canyon, deposits within the actively fluctuating zone continue to show decline throughout the <br />ecosystem, The sand-bar time series (1990 through 2002) suggests that the long-term fate of <br />beaches in the upper, critical reaches of the ecosystem will likely be in continued decline under <br />current ROD operations, Beach data collected in fall 2003 show decline in bar conditions at <br />many sites within the first 100 miles below the dam, The most probable reason for the <br />continuing decline of sand bars appears to be related to depletion of the ecosystem's sediment <br />supply, This trend might be reversed ifnew fine-sediment inputs from tributaries can be <br />managed more strategically using combinations of power-plant operations and BHBF's <br />following tributary floods, Declining beach trends correlate with the findings of the sediment <br />mass-balance project that indicate that new sand inputs from tributaries are transported <br />downstream relatively quickly rather than being retained throughout the river channel and <br />periodically re-deposited on diminishing bars. <br /> <br />Terrestrial Resources <br />Specific terrestrial resources of interest to the adaptive management program include <br />riparian vegetation, riparian breeding birds and waterfowl, invertebrates including Kanab <br />ambersnail, small mammals, and reptiles associated with the river corridor, Monitoring <br />approaches for terrestrial biologic resources underwent review in late 1999 (KAS expert panel) <br />and 2000 (Urqhart, 2000), Recommendations from these reviews were incorporated into 2001 <br />monitoring and research plans and continue to be evaluated and implemented through 2005. <br />A review of previous riparian studies and their applicability to monitoring, as well as the <br />information that these studies provide for assessing change, was completed in 200 I (Kearsley <br />and Ayers, 2001), Power analysis of historic data indicates that change detection of vegetation <br />GCMRC FY2005-2006 Draft Annual Work Plan (November 10,2003) <br />