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GREEN RIVER STUDY PLAN 25 February 2,2007 actions, including these flow and temperature recommendations, is to elicit a positive response by the endangered fishes. An integrated approach is necessary when implementing this Study Plan. Anticipated effects or uncertainties are interrelated and must be considered together to gain a better understanding of the effects of the flow and temperature recommendations. It is also noted that information needs and recommended studies ally closely with priorities identified in the Recovery Program guidance documents (Section 1.2.2). Nonnative fish management is vital to species recovery, and lower priority of some hypotheses related to this topic in this Study Plan does not diminish their importance, but rather reflects the focus of the Study Plan, i.e., the effects of flow recommendations or the degree to which an anticipated effect was understood. As mentioned above, an integrated approach is vital to program success, and nonnative fish response to flows and/or temperature modifications should be a priority study objective. For example, nonnative response to floodplain inundation threatens to over shadow benefits to endangered species and ignoring that threat would not be wise when designing and implementing such studies and recovery actions. Likewise, nonnative fish responses should be an integral consideration in any flow and temperature recommendation. Consideration should be given to tradeoffs among potential effects (e.g., base flow magnitudes and temperatures that maximize benefits to endangered fish may also benefit nonnative species that in turn prey upon and compete with endangered species; spillway use that enhances larval entrainment in floodplains may allow for escapement of nonnative fish from the reservoir into the river downstream, etc.). More integration and synthesis of historic and current information is urged as a first step in the development of sound scientific studies that best address hypotheses and make greater use of existing information. A synthesis of information is also needed to continue to review the scientific basis for the flow and temperature recommendations. Furthermore, study refinements through adaptive management are important to ensure that studies remain focused on the current most vital information needs. 3.3 Recommended Studies This section identifies the studies recommended to address anticipated effects, uncertainties, and information needs. Recommended approaches for implementing studies are also provided. The recommended studies are designed to more fully evaluate the flow and temperature recommendations. These recommended studies are either new studies or revisions of existing studies and are provided to the Recovery Program for revising the RIPRAP. Specific flows to evaluate one or more of these research areas may be requested for the TWG to consider along with the specific flow recommendations for the annual hydrologic condition. 3.3.1 FloodDlain Inundation for Larval Entrainment. Rearin2. and Subseauent Movement of Subadult Razorback Suckers into the Mainstem in Reach 2 Inundated floodplain bottomlands have been identified as the most important nursery habitat for young razorback suckers. Razorback suckers spawn in spring near the peak of runoff, and their newly hatched larvae drift downstream and into bottomlands that are flooded annually ,