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95% CI = 2.85 to 3.49) than in spring (1.88 fish/h, 95% CI = 1.54 to 2.30) or summer (1.73 <br />fish/h, 95% CI = 1.55 to 1.93). Spring and summer catch rates were not different (Xz = 0.54, 1 <br />df, p = 0.46). <br />Mean catch rates of all fish species in samples between autumn (3.05 fish/h, 95% Cl = <br />2.73 to 3.41) and summer (1.72 fish/h, 95% CI = 1.53 to 1.93) in 2002 to 2004 were also <br />different (Xz = 48.19, 1 df, p < 0.0001). Comparison of summer and autumn catch rates for <br />abundant species, such as brown trout, bluehead sucker, flannelmouth sucker, white sucker, <br />channel catfish, and smallmouth bass showed that capture rates were higher in autumn. <br />Colorado pikeminnow capture rates were not different between the two periods (p = 0.32). <br />Species richness in electrofishing samples collected from 2002 to 2004 was also higher in <br />autumn (N = 31, including hybrids) than in summer (N = 24). <br />The CPUE data for electrofishing samples in the 2002 to 2004 period showed differences <br />among years (XZ = 11.77, 2 df, p = 0.0028). Mean catch rates in 2002 were lowest (1.95 fish/h, <br />95% CI = 1.69 to 2.25), and different from 2003 (p = 0.0007) and 2004 (p = 0.015). Catch rates <br />were higher in 2003 (2.72 fish/h, 95% CI = 2.39 to 3.10) and 2004 (2.54 fish/h, 95% CI = 2.17 to <br />2.96); the catch rate difference among those years was not significant (p = 0.49). Species <br />richness in electrofishing samples collected in the 2002 to 2004 period was highest in 2002 and <br />2004 (N = 26 each year, including hybrid combinations) and lowest in 2003 (N = 23). <br />Capture rates of fish in samples when water was turbid were similar to or higher than <br />those when water was clear. For example, in the 1994 to 1996 period, average capture rates of <br />all fish species in turbid water (3.01 fish/h, 95% Cl = 2.40 to 3.78) were higher (Xz = 3.59, 1 df, p <br />= 0.0581) than when water was clear (2.3 fish/h, 95% CI = 1.97 to 2.70). In the 2002 to 2004 <br />period the same pattern prevailed because capture rates of fish in turbid water (2.51 fish/h, 95% <br />CI = 2.26 to 2.78) were higher (Xz = 1.28, 1 df, p = 0.26), but not significantly so, than those <br />when water was clear (2.28 fish/h, 95% Cl = 1.99 to 2.60). Catch rates for individual species <br />such as brown trout, bluehead sucker, flannelmouth sucker, white sucker, Colorado pikeminnow, <br />and smallmouth bass in turbid and clear water were also similar. Channel catfish capture rates <br />were slightly lower in turbid (5.0 fish/h) than clear water (6.9 fish/h, p = 0.06). <br />r <br />s <br />38