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found similar trends. A few snails and mayfly nymphs were also found. Amphipods were found primarily in the late summer and fall (Tables 5 and 6). Chironomids were found throughout the sampling period. Samples from the one-to-two-foot depth range produced small num- bers of organisms throughout the sampling period. The canyon area contained the largest number of organisms per square foot at this depth. Organisms from the one-to-two-foot depth range consisted primarily of chironomids in all areas. The largest number of chironomids per square foot was found in the canyon area. Freshwater shrimp were the second most abundant organism found with one exception. In the open area, mayflies and snails made up approximately 48 percent of the total number of organisms sampled (Table 4). The 10-foot depth was the most productive of the levels sampled. At this level, the inflow area samples. contained the largest number of organisms per square foot. Chironomids were the most abundant organism at the 10-foot depth and made up over 99 percent of the total number and total volume of organisms found in the inflow area. Amphipods were found in all the areas but were most abundant in the samples from the canyon area where they made up approximately 20 percent of the total number of organisms. Snails and mayflies contributed slightly to the total number of organisms although snails made up 10 percent of the total volume sampled in the open area. The 25-foot depth was the second most productive depth sampled. At this depth, the highest average number of organisms per square foot was found in the canyon area. Again, chironomids were the most abundant organism found in the samples, with the canyon and inflow areas containing the highest number per square foot. Amphipods were the second most numerous organism and in the open area, amphipods made up over 26 percent of the total number of organisms for this depth. 41