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Rakowski (1997) studied these habitats in the Ouray National Wildlife Refuge and showed that these low-velocity habitats occur adjacent to emergent sand bars. She found that most deep nursery habitats formed in abandoned secondary channels or chute channels on emergent bank-attached compound bars. She also found that the size of these geomorphic features was greatest after a large flood, and that other features that form shallow habitats are more abundant following low annual floods. More generally, she found that the Green River in the Uinta Basin adjusts quickly to changes in discharge, and bars aggrade during large floods. These findings were based on 1993 and 1994 channel measurements and flood passage simulation using the numerical model developed by Nelson (1989) and used by Andrews and Nelson (1989). Schmidt (1996) developed a simulation model of larval Colorado squawfish drift in the middle Green River to evaluate the role that dam releases and large-scale geomorphic organization play in the distribution of critical nursery habitat reaches. He found that habitat availability is greater in restricted meandering reaches such as Ouray than in fixed meandering reaches such as Labyrinth and Stillwater Canyons. Thus, flow recommendations that maximize habitat availability near Ouray will not necessarily accomplish the same objective downstream. Schmidt (1996) also found that squawfish larvae drifting downstream from the Yampa congregate more densely in the Uinta Basin if the Green River is at low discharge when the larvae enter it These findings collectively dictate that the channel conditions in critical nursery habitat reaches be regularly monitored, and that the processes of habitat formation in Labyrinth and Stillwater Canyons be carefully documented as done by Rakowski (1997) at Ouray. STUDY AREAS Ouray Below the Yampa confluence are Whirlpool and Split Mountain canyons. Ouray Wildlife Refuge is located approximately 45 km downstream from the 6