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Pucherelli et al. (1990) found that the number of backwaters was maximized in all three sites of Reach 2 (Island Park, Jensen, and Ouray) atflows of 1600 cft (45 cms). They also noted that backwater surface area was maximized at 1300 cft (37 cms) in Island Park and at 1870 cft (53 cms) in Jensen and Ouray. Not reported in the Flow Report was that total area of all three sites in Reach 2 was maximized atflows of 1300 cft (37 cms). See Figure 1 in the attached Excel Worksheet. There was no significant relationship between flow and backwater area in the Ouray reach; but, regression equations indicated that backwater area increased as flow decreased in Island Park and Jensen. Flows below 1300 cft that would have been more similar to unregulated conditions were not examined. Although Ouray is presently one of the primary reaches for pikeminnow nursery habitat in the Green River (Flow Report Page 4-20) and its backwater area was maximized (5.3 hectares) at 1800 cft (53cms), flows of 1300 cft (37cms) still maintained high backwater area (4.2 hectares) in Ouray. At the same time with flows of 1300 cft (37 cms), backwater area in the Island Park and Jensen reaches almost doubled in area to 2 hectares at each reach (Excel Figure 1). Response: The statement that backwater habitat area for Reach 2 was maximized at 37 m3/s is true, but this ignores the fact that this results from the predominance of backwater area in Island Park at this flow. Island Park is unoccupied habitat. If occupied habitat alone is examined (Jensen and Ouray), backwater area for Reach 2 was maximized at 53 m3/s (6.5 hectares). It is important to remember, however, that these values were obtained in a single year and that very different relationships could occur in other years depending on sediment transport and deposition patterns. It is also important to recognize that backwater area alone is not the only factor influencing recruitment of Colorado pikeminnow. Suitability is also important and it has been demonstrated that pikeminnow prefer deeper backwater habitats. Lower flows will reduce backwater depth. Comment: Rakowski and Schmidt (1997) studied geomorphology of nursery habitat in Reach 2 near Ouray. The Flow Report summarized the findings that the "availability of nursery habitat... during low- flow periods is dependent on channel form that results from. recent floods and antecedent channel conditions" (Page 3-50). Another important conclusion was that establishing a single target flow every year is inappropriate because habitat availability changes annually in response to peakflows (Page 3-50). Interestingly they found that habitat was maximized atflows much greater than base flow levels in some years; in 1993 habitat was maximized at close to 5000 cft (140 cms) and in 1993 at about 4200 cft (120 cms; Page 3-50). Surprisingly, the flow that produced the maximum amount of habitat in 1993 produced no habitat in 1994. For 1992 after some drier years, they reported that the maximum area of backwaters occurred at a discharge of less than 1200 cft (35 cms; Page 3-51). Response: The Rakowski and Schmidt (1997) report was important in developing a conceptual understanding of the relationships between antecedent sediment deposition patterns on the backwater to flow relationship. The data presented in our report and in the comment above indicate the fallacy of establishing a base flow target that would be applied across a range of hydrologic conditions and should caution one from placing too much stock in the types of comparisons made in the previous comment. It is important to note that the base flow 3