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i. consolidate the flow and river channels to maximize stream power and help induce braided channel characteristics; ii. mechanically cut banks and lower islands to a level that will be inundated by anticipated annual peak flows; and iii. mechanically clear vegetation from islands and banks in the single channel as needed to aid the widening process and make sediment available for recruitment to the river. Consolidating flows and widening the river at select locations by cutting banks and leveling islands can begin in Year 1 of the Program prior to increases in annual high flow, provided acceptable Program lands or Cooperator lands are available. Clearing vegetation and widening the river independent of consolidating flow should be concurrent with implementation of increases in annual high flows. Mechanical flow consolidating and river widening actions can occur independent of sediment augmentation, but greater increases in river width are expected at sites downstream of sand augmentation. [tlzis sentence not new, it is moved from the end of this paragraph]. The design and location of inechanical actions should be guided by available data, science, numerical modeling, and the availability of Program lands or cooperator lands. Where favorable conditions exist, mechanical actions may also be used to modify the topography, soils, and/or connectivity with the Platte channel on Program lands to support wet meadow conditions at these sites. Potential Effects: The mechanical action of consolidating flows will help shift the river to a braided condition, which widens the river and creates more sand bars (Physical Processes (PP) Hypothesis 3). Cutting banks and leveling islands in conjunction with pulse flows will widen the river (PP-3). Pulse flows are needed with both mechanical actions of consolidating flow and river widening to raise sand bars to an elevation suitable for least tern and piping plover nesting habitat (PP-1). Sediment augmentation is required in conjunction with increases in flows and contributes to wider sustainable channels, contributes to increases in occurrence of sand bars, restores stream bed elevation, and over time will promote the occurrence of a braided plan form in currently anastomosed reaches of the river (PP-2). Creation of ephemeral sand bars (braided condition) with Land Plan Table 1 characteristics will increase least tern and piping plover production on riverine habitats and will reduce predation by shifting nesting locations from one year to the next andlor maintaining separation between nests and river banks (Tern and Plover (TP) Hypotheses 1 and 3). Creating a wider, braided channel will reduce channel depths, and increase forage opportunities for least tern and piping plover chicks (TP-4) leading to improved growth and survival (TP-1). Increasing channel width, sand bars, and shallow water depths (braided condition) will increase roosting habitat for whooping cranes (Whooping Crane (WC) Hypothesis 1), thereby increasing migration survival of whooping cranes. Restoring stream bed elevation will increase water stage for a given flow, which will increase growing-season groundwater elevations in adjacent meadows, increasing the area/extent of wet meadow habitat. Increasing wet meadows during migrational times will increase migration survival of whooping crane. September 1, 2006 Adaptive Management Plan 23