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<br /> <br />the riffle and all-habi.tat categories (methods 3 and 6) greatly <br /> <br />.~,~jtk . <br />excee4.i~i\... <br />}/i;~:~~f[~"; <br />ins trea.m' <br /> <br />available late summer flows. This could create rather than resolve <br /> <br />flow conflicts by damaging a biologist's credibility or falsely implying a need <br /> <br />for upstream storage of water. <br /> <br /> <br />Estimates of MF based on statistical documentation methods showed generally <br /> <br />similar levels of bias with from four to six unbiased recommendations. J!t?i1:h the <br /> <br />exception of Method 5 (AF minus LSD for riffles) I no significant trends were <br /> <br />observed when es timates were not unbiased. <br /> <br />All of the biased recommendations <br /> <br />for Method 5 were biased low. Combining all unbiased and upwards-biased recom- <br /> <br />mendations for each method showed that methods 7 and 4 generateds~.&~ificant <br />-....... .... <br /> <br />numbers of recommendations that were not biased low. <br /> <br />Although none of the wetted perimeter methods provided consistently unbiased <br /> <br />recommendations, statistical documentation of MF recommendations offers certain <br /> <br />ad van tages over sub j ec tively identified recommendations. <br /> <br />Mos t obvious among <br /> <br />these is precise documentation of estimates through the use of defensible sta- <br /> <br />tis tical tools and the removal of investigator bias. <br /> <br />Though we found none of <br /> <br />the wetted perimeter methods to be cons.istently unbiased.(according to our defi- <br /> <br />nition) or different from each other, statistical documentation methods (such as <br /> <br />methods 7 or 4) may be preferred over subjective methods where the wetted peri- <br /> <br />meter approach is the only method that will be used and an objective MF selec- <br /> <br />tion technique is desired. <br /> <br />Habitat Retention <br /> <br />Methods 10 and 14 (where all three 'criteria were met for the average of all <br /> <br />riffles and where two of three criteria were met for a critical riffle respec- <br /> <br />10 <br />