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Based on one year's data, Pucherelli and others (1990) showed that available habitat in the Uinta Basin was maximized at base flows of about 45 m3/ s (1600 ft2/ s). However, Rakowski (1997), showed that the baseflow at which habitat is maximized changes from year to year because of in-channel redistribution of sand bars. Schmidt (1996) also showed that different flows maximize habitat at Ouray than in Labyrinth and Stillwater Canyons, which are approximately.325 km. downstream. Thus, there is a need to continue monitoring channel conditions in critical nursery habitat reaches because (1) annual channel changes affect the distribution of available habitat, and (2) annual changes may affect the relative distribution and characteristics of habitat in the two critical nursery habitat reaches. In spring 1996, runoff projections for the upper Green River were very large. The U.s. Bureau of Reclamation and the Utah Division of Wildlife Resources contracted with Utah State University to measure channel response to passage of the flood in areas of critical nursery habitat This contract supplemented on-going research on the geomorphic basis of nursery habitat in the Uinta Basin and in Labyrinth and Stillwater Canyons. The purpose of this report is to summarize our 1996 field activities and provide a preliminary assessment of the significance of our data in relation to that collected since 1993 at these sites. BACKGROUND The life history of the Colorado squawfish has been summarized by Stanford, (1994); Tyus, (1991); Tyus and Haines, (1991); and Tyus and Karp, (1991). The Uinta Basin, Labyrinth Canyon, and Stillwater Canyon are the parts of the Green River to which Color8;do squawfish larvae drift in mid-summer. There, rearing of age 0 and juvenile Colorado squawfish occurs in backwaters and low velocity areas. 5