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<br />4. <br /> <br />5. <br /> <br />'. <br /> <br />Flow Regimes: <br />a. Neither the Reasonable Q",j Prudent Alternative or <br />the Preferred Alternative flow element alone will <br />remove jeopardy. Jeopardy may only be removed if <br />all elements of the reasonable and prudent <br />alternative are implemented. This includes the <br />MUltiple Withdrawal structure, research, etc.. <br />b. The reasonable and prudent alternative is <br />considered by the Fish & Wildlife Service and the <br />researchers to be the best for maintenance of the <br />HBC. <br />Present populations <br />a. The LCR population should be considered as a <br />separate population. <br />b. The LCR population is considered presently stable <br />c. The mainstem population is centered around discrete <br />locations and is low to non-existent in terms of <br />recruitment. Very dependent on the LCR population <br /> <br />D. DISCUSSION POINTS AND QUESTIONS <br /> <br />If we cannot displace non-native fish what is being done <br />getting data from other systems to evaluate flow <br />temperature impacts? <br /> <br />1. <br /> <br />with <br />and <br /> <br />a. Upper Basin information = non-natives decrease as a <br />result of high spring flows in 1984-85. By 1987 non- <br />native fish densities had returned to pre-84" levels <br />b. Grand Canyon large non-native fish information: <br />* Channel catfish did not decrease after 84-85 flows <br />* centrarchids did decrease but quickly reinvaded <br />* Carp remained at high levels <br /> <br />2. Daily fluctuations - Is less better? Is the intent to <br />increase temperature? Intent to decrease velocities? <br /> <br />a. Directed to stabilizing the backwaters <br />b. Stable backwaters will lead to warmer water. Stable <br />water will also lead to clearing water <br />c. with clear water the daytime activity of the HBC is <br />reduced <br />d. Sight feeders are aided by clearer water. <br />* Brown trout are heavy predators on HBC <br />* Rainbow trout also prey on HBC but at lesser levels <br /> <br />:3. Backwater roles - do the non-natives also make use of the <br />backwaters? To the detriment of the natives? <br /> <br />a. The spring spike is designed to displace the non-natives <br />from the backwaters prior to the native young arriving <br />b. The stable backwaters benefit all young fish who use <br />shoreline and backwater habitats <br />c. Fluctuating flows in winter destabilize backwaters. <br />Impacts non-natives primarily <br />