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<br />GW A is a useful reference for identification of habitat availability. For habitat <br /> <br /> <br />availability, WUA is much more informative than individual pool cross sections, since it <br /> <br /> <br />includes both pool and run area exhibiting observed depth and velocity requirements. The <br /> <br /> <br />mean of the inflection points for WUA for adult Colorado squawfish day habitat was at <br /> <br />104 cfs. These results suggests that minimum flows meant to protect Colorado squawfish <br /> <br /> <br />daytime habitat may need to be about 14 cfs higher than those determined by rime <br /> <br /> <br />inflection points (90 cfs). <br /> <br /> <br />The distribution of pools was found to be very patchy and often separated by long <br /> <br /> <br />distances. The patchy nature of pools in the channel suggests that pool habitat <br /> <br />availability may be limited during times of very low flows. Larger and deeper pools may <br /> <br />provide better conditions during low flow events when fish can not migrate up or down <br /> <br />stream due to shallow rimes. If, however, squawfish movement between pools is not <br /> <br /> <br />restricted by low flow, then pool habitat availability is probably not a concern. <br /> <br /> <br />During their evening forays squawfish moved across shallow rimes taking <br /> <br /> <br />temporary positions in the shallower/faster habitats (Miller 1997). The mean of the curve <br /> <br /> <br />break for nighttime habitat was 85 cfs in strata 6 and 8 combined, very similar to the <br /> <br /> <br />mean curve break for runs (86 cfs) in those strata. The inflection points for foraging <br /> <br />squawfish WUA is less than found for riffles (93 cfs). This suggests that a 93 cfs <br /> <br />minimum flow based on rime maintenance will also be adequate to provide foraging <br /> <br />habitat for endangered Colorado squawfish in the upper strata. <br /> <br />The maintenance of passage flows supercedes the concerns about habitat <br /> <br /> <br />availability for endangered fish because they are able to select their habitats. Squawfish <br /> <br /> <br />movement patterns were different between the high and low flow years. Movements <br /> <br /> <br />were longer and more dramatic in the high flow summer of 1997, than in the low flow <br /> <br /> <br />summer of 1996 (Miller 1997). In 1996, when low flows were near 100 to 125 cfs for ten <br /> <br /> <br />31 <br />