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Table 5. Comparison of Peak discharge and average June flow, to the onset of spawning, date of <br />18°C, larval drift catch rates (#/1000 m3), and total transport abundance (#fish/hour) at <br />Westwater (WW) and Moab (MO), using Pearson's correlation coefficients. <br />Correlations significant to the p = 0.05 level are shown in bold. <br />Pearson's rz Peak Onset of DD to Date of Avg. June WW WW MO <br />probability p = discharge spawn spawn 18°C flow (#/1000 m') #fish/hour (#/1000 m') <br />Onset of +0.96 <br />spawn 0.01 <br />DD to spawn +0.82 +0.94 <br /> 0.09 0.02 <br />Date of +0.89 +0.98 +0.97 <br />18°C 0.04 0.002 0.007 <br />Avg. June +0.98 +0.98 +0.80 +0.94 <br />flow 0.003 0.005 0.04 0.02 <br />WW +0.74 +0.65 +0.36 +0.57 +0.61 <br />(#/1000 m3) 0.14 0.23 0.54 0.31 0.26 <br />WW +0.35 +0.21 -0.11 +0.12 +0.17 +0.88 <br />#fish/hour 0.56 0.73 0.85 0.84 0.79 0.05 <br />MO +0.72 +0..88 +0.99 +0.94 +0.82 +0.29 - 0.18 <br />(#/1000 m3) 0.16 0.05 0.002 0.02 0.09 0.64 0.77 <br />MO +0.46 +0.68 +0.80 +0.80 +0.56 +0.20 - 0.13 +0.88 <br />#fish/hour 0.43 0.21 0.10 0.10 0.32 0.73 0.82 0.05 <br />Peak discharge appeared to affect the relative abundance of other native and non-native <br />fishes. Particularly in Westwater, low flows were associated with increased relative abundance <br />ofnon-native cyprinids, as shown in Figure 3. In the high water years of 1993 and 1995 the <br />percent ofnon-natives present in the drift was reduced. In 1994, the lowest water year, relative <br />abundance of the non-natives was highest, however volumetric catch rates of both native and <br />non-native fish were high (Figure 11). At both Westwater and Moab, the percent of Colorado <br />pikeminnow larvae in the drift was usually highest in the moderate to high water years of 1993, <br />1995, and 1996. <br />Peak discharge was not linearly correlated to total transport abundance ofnon-native <br />cyprinids, nor were densities correlated between sites (Table 6). At Westwater, abundance was <br />highest in the moderate and low water years of 1996 and 1992, and lowest in the high water <br />years. At Moab, transport abundance was much higher, and more variable, with the highest <br />abundance in the high flow year of 1993, and the next highest abundance in the lowest flow year <br />(1994). At Loma, yet a different pattern was seen. Non-native production varied independently <br />at each site. <br />11 <br />