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(RK 291.5) Rock Creek (RK 278.6); Chandler Falls (RK 266.6); and Rabbit Valley (RK 238.1). On occasion it was necessary to incorporate data from the most proximal wild card site in the long term analyses. Sampling targeted two general components of the fish community: 1. small sized cyprinids and the early life stages of all species occupying low velocity habitats and 2. juvenile/adult main channel dwellers (large sized fish). Small sized fish were sampled in backwaters throughout the canyons according to Interagency Standardized Monitoring protocols (refer to the ISMF handbook for details (USFWS 1987)), i.e. sampling frequency of two backwaters every 8 km. A two person beach seine (4 m x 1.2 m; 3.2 mm mesh) was used. Fish were either identified and enumerated in the field or preserved in 10% buffered formalin for lab analysis. Sampling for the main channel fishes was conducted primarily during the crepuscular-and night time hours. A variety of techniques were employed at each site. Six trammel nets (23 m x 1.8 m [25 mm or 12 mm inner mesh]) fished in low flow, main channel habitats (pools or along eddy lines) were checked on two hour intervals through. the evening until midnight. The trammel nets were reset at dawn and fished for 2-hr sets. Three hoop nets (0.6 m diameter, 3 m in length [12 mm mesh]) were fished through the night in shoreline habitats. Electrofishing (4.8 m inflatable sport boat equipped with a 4500 watt generator and Coffelt Variable Voltage Pulsator (VVP-15)) was conducted along both shorelines in the evening prior to setting trammel nets and repeated after the trammel nets were pulled. All target species (Gila spp., Colorado pikeminnow) >175 mm were tagged with Passive Integrated Transponder (PIT) tags. All Gila spp. were photographed on a grid (1 cm2) board and subjected to a series of morphometric measurements and rankings (refer to the ISMP handbook; USFWS 1987). Body scales were collected-above the lateral line immediately posterior to the insertion of the dorsal fin from all target species for later analysis. It was often difficult to come to a consensus when identifying Gila spp. collected in Deso/Gray. Many of the fish were recorded as "chub" with a tendency toward G. cypha or G. robusta, but the researchers did not feel comfortable committing to a specific classification. In 1993, all chubs collected were simply field identified as Gila spp. To be consistent in data presentation native chubs have been reported collectively as Gila spp., however observed species distributions and trends were discussed anecdotally. For the purposes of discussing movement, chub capture locations were identified by site. A sampling site could be a 0.5 - 1.0 km stretch of river. Movement within that site was not detected. All catch per unit effort (CPE) values have been standardized to fish per 23 meter net- hour (trammel nets), fish per actual hour electrofishing, and fish per square meter of low velocity habitat sampled (seine hauls). All locations are presented in river kilometers from the confluence of the Green and Colorado Rivers (RK 0.0). Green River flow as recorded by the United States Geologic Survey (USGS) at their Green River, UT gage (No. 09315000) is reported as cubic feet per second (cfs). All other units of measure are metric. vii