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flanne1mouth sucker, speckled dace, roundtail chub, and mottled sculpin) made up 90% of the catch in shoreline drift nets. Of the three non-native species in drift (white sucker, fathead minnow, and green sunfish), only the white sucker made up a significant proportion of the drift (8.6%). Weekly Drift Patterns Drift of larval fishes at the Palisade Site was monitored for 10 weeks, from July 6 to September 13, 1984. Variations in mean weekly drift densities appear to be related to river discharge and water temperature (Fig. 7). Few fish w~re found drifting before and at the initiation of drift net sampling. Drifting fish were first detected the second week of July when water temperatures first reached 16.0 c. Initially, trends in drift densities followed closely trends in water temperature. Mean weekly densities increased from 0.16 fishes per 1000 cfw in the second week of samp1 ing to a peak of 2.34 fi shes in the fourth week as river temperatures rose from 16 to 20 C and discharge decreased from about 18,500 to 11,250 cfs (Fig. 7). The continued warming and decreased discharge of the river in the fifth week of sampling, however, did not result in increased drift; mean weekly density at that time dropped to only 0.31 fishes as the river temperature peaked between 20.5 and 21.0 C. No drifting fishes were observed the seventh week of sampling (August 17-23), suggesting that drift activity was completed. But, a second pulse of drifting fishes was observed in late August and early September as the mean weekly density rose to 1.33 fi shes per 1000 c fw. Thi s pul se cannot be explained as a function of river temperature or discharge, since these parameters were relatively stable during this period (Fig. 7). This second pulse probably reflects the history of spawning activity in the area. Apparently, conditions on the river were suitable for two closely-spaced spawning events, making available one large egg hatch followed by a second smaller one. Di e 1 Dr i ft Drift nets were set over a 24-hour period to evaluate diel patterns of drifting fishes. . This sampl ing was conducted during the week of maximum drift to insure sufficient numbers of fish for the analysis. Paired shore1 i ne surface samp1 es , ta ken at about 2-hour intervals, i nd icate that drift densities at the Palisade Site were related to time of day (Fig. 4). Drift densities were highest between midnight and 0400 hours (0.65 fish in 1000 cfw) and between 2000 hours and midni ght (0.60). About 60% of the drift ,was recorded during these two time periods. The number of drifting fishes between 0400 and 2000 hours was relatively consistent, varying between. 0.26 and 0.11. The lowest drift dens ity was observed between 1600 and 2000 hours. An analysis of variance revealed a significant difference (p=O.Ol) between the hourly means. By using Fisher's least significant difference procedure for multi pl e compari sons, it was determi ned that there were significant differences (p<O.OI) between the two maximum values and the 182 I ( ~ I -, -,,,,._~..._,,-,,,,,~----~~~~.,,.