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I I I I I I I I I I I I I I I I I I I or early July, remained connected the river channel (and therefore inundated) until at least early August. This is believed to be a desired condition for better growth and survival of native fish larvae, but high water levels in nursery habitats and constant inflow of water from the river lowered water temperatures and raised turbidity levels, which probably reduced light trap sampling efficiency. Additionally, in habitats such as Millard Canyon, high water inundated rooted vegetation and flash floods caused by local rainstorms washed woody debris into nursery habitats. Over the season, the inundated rooted vegetation died, and subsequent decay of vegetation and woody debris possibly reduced the water quality of important nursery habitats (qualitative observations suggested that this was the case; water inside Millard Canyon during late July-early August had a yellow-brown tint). Presence of large amounts of woody debris and abundant rooted vegetation also reduced the effectiveness of seining. 1995, Colorado River inflow to Lake Powell, 11-13 July.-A total of 13,734 fish was collected in five light trap samples during 11-13 July (Table 9). Nonnative minnows dominated the catch (> 99% of the total number collected), with red shiner (50%, GMcpe = 220.4), sand shiner (20%, 92.7), and fathead minnow (30%, 133.3) predominating. Threadfin shad and common carp were the other non natives collected. Native fishes were represented by the collection of one speckled dace. High water levels greatly reduced the effectiveness of sampling and prevented sampling in many important nursery habitats (e.g., flooded side canyons). Summary of captures of larval razorback sucker in the middle and lower Green River systems, 1992-1996.-Focused efforts to collect larval razorback sucker for documentation of successful reproduction and abundance and distribution of young started in 1992 in reaches of the middle Green River (from confluence of the Yampa and Green rivers, RK 551.7, downstream to the Ouray Bridge, RK 397.0; concentrated in the Escalante, RK 511.0-482.7, Jensen, RK 482.7-443.0, and Ouray, RK 443.0-397.0, reaches) as part of the Five-Year Flaming Gorge Flow Recommendation Investigation Research Program; sampling conducted by the U.S. Fish and Wildlife Service, Vernal, Utah. Based largely on results of the 1993 NPS/LFLlarval razorback sucker sampling in the lower Green River, sampling under the Flaming Gorge Research Program expanded in 1994 to include reaches of the lower Green River (San Rafael/Green River confluence, RK 155.2, inside Millard Canyon, and in the Anderson Bottom-Bonita Bend area); sampling conducted by the Utah Division of Wildlife Resources, Moab, Utah. A monitoring program for razorback sucker in the Green River system started in 1996 and includes sampling for razorback sucker larvae in the middle and lower Green River. Captures of larval razorback sucker in the middle and lower Green River systems , during 1992-1996 by gear type and principal collector are summarized in Table 11, and show high variability in catch rates among years within river sections. In 1996, when sampling efforts were standardized between the middle and lower Green River, catch rates of larval razorback sucker were similar between the two river sections. Diet of Adult Red Shiner: 1994 (Objective 5) Percent of adult red shiner examined for diet with empty digestive tracts was low and ranged from 4% (1 out of 28) for fish from Millard Canyon to 17% (4 out of 24) for fish from Lathrop Canyon (Table 12). Organic detritus occurred in most digestive tracts (63-84% of those with food) and on average contributed 59-72% to the total volume of food in each digestive tract. Insects, including parts, chironomid larvae, simulid pupae, and corixids, were 24 / (\