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active nest sites was 1.2 acres for the eight dates examined. This was significantly <br />greater than the mean of 0.6 acre for systematic sample sites (Ziewitz et al. 1992). <br />Channel Width <br />Mean channel width measured at nest sites was 975 feet, significantly greater than the <br />mean of 660 feet for systematic sample sites (Ziewitz et al. 1992). <br />Off- Channel Nest Sites (Sandpits) <br />Sandpit habitat consists of fine- grained sand, which is dredge spoil from commercial <br />gravel mining operations (Jenniges and Plettner 1999). Spoil piles at sandpits often <br />remain unvegetated for 6 to 8 years (Currier and Lingle 1993). <br />Managed Sandpits <br />Management strategies include electric predator fences, fencing for human control, <br />signing with "do not enter" signs, vegetation control on the nesting area, placing drain <br />tiles and driftwood on nesting areas, and clean up of potential predator hiding places in <br />the general vicinity of the nesting area. Additional management techniques, used as <br />warranted, include strobe lights, snake fences, and traps and predator removal by USDA <br />Animal Damage Control (Jenniges and Plettner 1999). <br />Proximity to river <br />Orthophotos from 1998 and other aerial photographs are available to estimate the location <br />and proximity of off - channel sandpits and the river. <br />Size <br />Orthophotos from 1998 and other aerial photographs are available to estimate the size of <br />off - channel sandpits. <br />Distance and density of tree and brush cover <br />Gross estimations are obtainable from 1998 infrared orthophotos and other aerial photos. <br />Isolation <br />The 1998 GIS database provides information to identify primary land uses that represent <br />sources of potential disturbance. <br />Habitat use <br />Draft Baseline Report, July 2002 <br />4 -14 <br />