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DISCUSSION The bottom fauna study was initiated to classify and measure the relative abundance, succession and distribution of bottom organisms in the new reservoir. During the first years of the study, operational problems led to inadequate sampling (1964 and 1965). A full scale sampling program was conducted in 1966. After this time, the study was discontinued because project personnel felt that bottom organisms contributed only slightly to the food web of the reservoir and because of the limited sampling time available. The 1964 and 1965 data show only the species composition of the bottom fauna. The sampling during these two years was so limited that no conclusive results were obtained. Cowell and Hudson (1967) report that wave action limits the number of invetebrates present in shallow water. Wave action probably was the cause for the low numbers of organisms in the samples from the one- to-two-foot depth range throughout the reservoir. Organisms were numerous in the samples taken from the canyon area at this depth. The canyon area is characterized by deep water and sheer rock walls. The limited littoral area in the canyon is generally protected from wind action and consequently may support more organisms per square foot than the more extensive littoral habitat in the open and inflow areas. Stomach analysis data collected in 1966 show that bottom organisms make the greatest contribution to the diet of rainbow trout in the canyon area. Diptera were the most important in this area making up over 16 percent by number of food items in the diet. Mayflies were the most numerous bottom organism in the diet of rainbow in the open area. The overall contribution of bottom organisms to the diet of rainbow trout in the inflow area was very small during the 1966 sampling (Table 7). Diptera were the only bottom organism that contributed significantly to the food of the rainbow trout in the reservoir (Wiley and Varley, 1978.) 45