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I I I I I I I I I I I I I I I I I I I flow). Density data is now based on wetted width of 55.2 m at 1,400 cfs for the Colorado River and a wetted width of 56.2 m at a flow of 200 cfs for the Yampa River. In theory streams with higher habitat diversity support a more diverse community. Habitat diversity was found to be higher in the 15-Mile Reach and peaked near 1,400 cfs, with the peak at Duffy near 180 cfs (Stewart 2000). Traditional jnstream flow methods have based flow recommendations on optimizing habitat availability. We believe this is generally valid. and are attempting in this study to collect data to show how the fish community interacts with habitat. Results of habitat analysis show large differences in habitat composition between Duffy (Yampa River) and Com Lake (Colorado River). Duffy is comprised of low velocity habitats. At flows below 150 cfs pools are the dominant meso habitat, and above 150 cfs runs are in the majority (Figure 5). The shoal pool (depth from 0.2 to 0.5 m) is the most common type of pool at Duffy at all modeled flow (Figure A51). The shoal run (depth from 0.2 to 0.5 m) is the most common run type at flows below 300 cfs and at flows over 400 cfs shallow run habitat becomes most common (Figure A51). Rime area increases between 150 and 400 cfs, and deep rimes are very rare below 400 (Figure A5!.) Pools are uncommon in the Colorado River at 1400 cfs and for the range of flows mapped (Figure 6). Deep pool was the only pool habitat to increase with flows (Figure A52). Runs decline with increased flow on the Colorado River in contrast to an increase in run habitat at Duffy with increasing flow. The medi-run (I to 2 m) is the most common run habitat at all flows at Com Lake (Figure A52). Riffies are the dominant meso-habitat type at flow over 900 cfs at Com Lake. At 1400 cfs deep and very deep rimes are common (Figure A52). 41