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METHODS Geomorphic Component Flow patterns and the location of shorelines were mapped in the four study reaches to measure the areal extent and distribution of eddies and low-velocity zones at a wide range of discharges. These data were combined with data describing substrate and bank materials. Maps were made at discharges between 2,100 and 27,000 ft3/s. Surficial geology of the river corridor was mapped to determine the distribution of alluvial. deposits, and to compare and contrast the relationship between these deposits and available habitat in each of the study reaches. Cross sections of the channel were measured to help characterize the geomorphic variability within and between reaches. Finally, historical oblique photos taken in Desolation and Gray Canyons were located through archival searches. These photo sites were located in the field, and photos were matched to identify geomorphic changes.that have taken place in the past (refer to Report A for a more in-depth discussion of methods). Biological Component Nursery Habitat Backwater and low velocity flow habitats of Desolation and Gray Canyons were sampled four times each year from 1994 through 1996 for the presence of endangered fish. The samples were timed to coincide with critical periods in the lives of YOY chubs and Colorado pikeminnow post swim-up (late July/early August), fall (late September/early October) and post-winter (late March early April). In June, 1994, every backwater encountered between RK 345.9 and RK 212.4 was sampled. The same sampling regime was attempted in July, 1994, but because of the large number of backwaters encountered, this was abalidoned at RK 281.6, from which point only the first backwater encountered in each 1.6 km section was sampled. Due to high water, June sampling was eliminated from 1995 and i 996 and also July.1995. April 1997 was canceled because it was thought to be too early to effectively sample swim-up. All subsequent sampling coincided with established adult chub monitoring stations previously established by UDWR {RK 301.7-293.6, RK 285.6-277.6, RK 261.5-253.4 (all in Desolation Canyon) and RK 237.3-229.3 (Gray Canyon)} (Figure 1). Sampling began at the upstream end of the study reach and continued in a downstream direction. Backwaters were sampled by a crew of four- to six. Each backwater encountered was approached with caution in an attempt to avoid "wash" entering the backwater from the boats. Two types of sampling were conducted: habitat features and fish community. Habitat Features Sam~g Backwater habitat measurements and observations were taken along three transects. All physical measurements were made after seining to avoid disturbing the fish. The length (m) of each backwater was measured from the center of the mouth to the extreme upper end using tapes, range finders or known paces. Width measurements (m) of each backwater were taken across the mouth and at 1/3 and 2/3 the distance from the mouth to the upper end. Depth (m) measurements were taken along each width transect with a 2 m staff gauge. The deepest point along each width v