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also noted that conservation recommendations, which may implemented at the discretion of the action agency can be included in a biological opinion. Flooding Important factors were listed as temperature, magnitude, and duration of floods; the ratio of base flow to peak flow, timing and frequency of the peak; and the rate of the hydrograph. Floods were defined as: - Maintenance: < 31,OOOcfs; = power plant capacity; estimated occurance of once/year Habitat building: 45,000+/-; 1/8 years Uncontrolled: > 31,000 + tributary flow; turbid water; 1/100 years Timing, if controlled should tend to mimic a natural hydrograph. Floods are important to create/maintain habitat. Impacts from human induced changes to the environment are cumulative, so thinking should not be focused on one type of impact at a time. Magnitude, duration, ratio of peak to base flow and rise/fall of hydrograph scarcely if ever influences adult (>175mm) to a detectable level. However, eggs and larva and juveniles are affected. Therefore, the focus for developing recommendations/ a reasonable and prudent alternative for removing jeopardy, and for future research needs to be on recruitment/early life stages. Most participants recommended that flushing and/or habitat maintence flows be the shortest duration which would achieve habitat maintence/building. However, flows should still mimic the natural hydrograph, with the incorporation of the peak for habitat maintenance/building. The trend in response to floods in other canyons seems to be a significant drop in catch rate of non-natives, but this is followed by a recovery once high flows are reduced. Native fish are better adapted to flood flows. It would take 3 orders of magnitude over base to displace non-natives in Grand Canyon, which is probably higher than anything we will ever see. Controlled floods should be managed to minimize effects on strong year classes. Pood Ba.e :2