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276 1962, Koski 1966, and Vaux 1962). In this study, however, when fine sediment was considered as a single variable influencing one area at one time the re- sults differed from those of other authors who compared the effects of the increased fine sediment as it affected the same area over time. As fine sediment increased in the stream channel, stream depths, pool quality, and percent pool ratings increased, while channel gradients and ele- vations decreased. These variables usually equate with increased fish numbers and could bias or hide any effects the increases in fine sediment may have. The multivariate analysis, however, also indicated that the amount of fine sediment in the channel has no effect on any observed variations in fish num- bers (Fig. 1). Although no trend developed between increasing fine sediment and the means of total fish populations, rainbow trout decreased as fine sedi- ment increased, and brook trout appeared to increase. Dolly Varden and brook trout were the only species found in transect areas of stream channels con- taining over 70 percent fine sediment. No clear trend was identified between total fish populations or individual fish species with percent of rubble, although rubble was the only streambed material class that had explained variation (2 percent for total fish numbers). Diversity of fish species was reduced in areas of streams having more than 50 percent fine sediment, but reduced diversity was not the case in chan- nel areas with more than 50 percent rubble and boulder. Fish numbers, fish lengths, and fish species did not correlate with percent of boulder or gravel in the stream channel. Effect of Channel Gradient on Fish Populations As channel gradients (based on the average channel gradient over the complete 200-foot sections) increased from 2 to 4 percent, mean fish numbers per stream length increased. As channel gradients increased above 4 percent, fish numbers declined steadily; no fish were collected when the average gradi- ent was above 25 percent. Fish accumulative length ratings per sample area did not always follow the same trends as fish numbers, in some cases increasing with increasing channel gradients. Young-of-the-year chinook salmon, utilizing the lower stream segments, peaked at 4 percent channel gradient. In contrast, cutthroat trout, mountain whitefish, and dace did not appear in sampling until 4 percent was reached. Rainbow trout numbers peaked at 5 percent gradient. This may have been due to steelhead trout spawning higher in the streams than chinook salmon. Cutthroat trout, which utilize higher elevation areas, did not peak in population numbers until about 10 percent channel gradient. i