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transect (Dmax) was located and recorded. One depth was then taken on either side of this point and halfway from that point to either shore (D 1 and D2). Two depth measurements were taken: depth from the top of the substrate to the surface and a water plus substrate depth were measured. The latter was measured by pushing down on the staff gauge with moderate pressure and recording total depth to the top of the water column. Sub-surface temperatures (°C) were taken at each Dmax. If Dmax exceeded 1 m, a water temperature was also taken just above the bottom. Aspect of the backwater mouth was recorded on a 1-5 scale. A value of "1" indicated the mouth opened parallel to downstream flow. If the mouth opened parallel to flow in an upstream direction, it received a "5". Backwaters which opened perpendicular to flow received a value of " 3". Turbidity of the backwater at the three width transects, and in the main channel, were evaluated on a scale of 1-3: "1"meaning clear and " 3" meaning exceptionally cloudy. Cover (overhanging vegetation, submerged vegetation, rocks, boulders, etc.) on and in the backwater was estimated visually and recorded as percent of the backwater surface area. Each backwater sampled was first categorized by physical type; which was determined by its method of formation or current condition. These categories included horseshoe vortex, isolated pool, low velocity flow-through, migrating-sand-wave, shoreline eddy, secondary channel and are described in Table 1(Report B). Data for physical type classification was complete for the years 1994-1996, but incomplete between 1990-1993. This was due, in part, to changes in the classification system and personnel in 1994. Analyses on these categories were conducted only for those backwaters for which a type classification was available. Fish Community Sam ling Fish were collected by seining. If large enough, the backwater was seined at three different locations with a 4 m x 1 m seine of 3 mm mesh. The seine was pulled across the backwater at the mouth, at a point I/3 the distance from the mouth to the upper end, and at a point 2/3 the distance from the mouth to the upper end. These usually coincided with physical measurements of each backwater. In the case of a parallel seine, however, depths were taken at the outside edge of the net and at points 1/3 and 2/3 the distance from that edge to shore. If the backwater was too deep to wade, the seine was pulled parallel to shore. A smaller (1 m x 1 m) seine of 1.5 mm mesh was used in narrow, shallower backwaters or when larval fish were present. Extremely small backwaters were often sampled completely with one sweep. Each seine haul was examined for the presence of native fishes. Native fishes were placed in a live well until the entire seine had been closely scrutinized. They were then identified to species, measured (TL mm) and released live into the backwater. A11 other fish caught were counted by species and cohort (sub-adult or adult). Samples that were too large to be counted immediately were preserved in 10% formalin in Whirl-pak® bags for later examination after removal of native fish. Preserved -fish samples were examined by UDWR personnel, or by the Larval Fish Laboratory at Colorado State University, Ft. Collins, Colorado. Length (m), width (m) and depth (m) measurements associated with each seine haul were recorded. Fin ray counts were used to categorize young chubs in the field, when possible (i.e. when fish were > 35 mm TL). ~~~ Monitoring ~~ In addition to four trend sites, two or three wild card sites were sampled each trip to pursue the Colorado pikeminnow spawning issue and to determine if repeated monitoring efforts ~. ~~ , in these short stretches of river affected catchability. The wild card sites included: Flat Canyon vi