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. DRAFT Table 6. SUmmary statistics for Colorado Squawfish depth utilization. . Sample N Mean variance Minimum Maximum 1987 291 3.68 2.54 0.90 8.00 1988(n)1 208 4.20 5.16 1.20 10.00 . 1988(i)2 144 3.08 4.60 0.30 7.00 1 = 1988 data for no ice cover 2 = 1988 data for ice cover . A statistical comparison of the 1987 versus 1988 depth utilization for no ice cover showed a significant difference for the variance and the means (F=2.03, T=-2.84). However, this difference is related to a single observation at 10.0 feet in the 1988 data set (see Figure 22 and Table 6) and visual inspection of the frequency data would suggest that the two data sets are in fact very similar. The statistical test between the 1988 ice versus no ice data showed no significant difference in the variance (F=1.12), while the means were significantly different (T=4.65). Again, visual inspection of the frequency data shows that this significance is driven by the three observations below 1.0 foot in the 1988 ice cover data. . . Velocity The raw frequency histograms for velocity utilization for the 1987 and 1988 data without ice and the 1988 data with ice are contained in Figure 23. Summary statistics for each data partition are contained Table 7. . Table 7. Summary statistics for Colorado Squawfish velocity utilization. Sample N Mean Variance Minimum Maximum 1987 292 0.69 0.23 0.00 2.20 . 1988(n)1 208 0.67 0.29 0.00 2.30 1988(i)2 144 0.56 0.29 0.00 1.50 1 = 1988 data for no ice cover 2 = 1988 data for ice cover . . A statistical comparison of the 1987 versus 1988 velocity utilization for no ice cover showed no significant difference for the variance and the means (F=1.25, T=0.44). Visual inspection of the frequency data further support the statistical tests. The statistical test between the 1988 ice versus no ice data showed no significant difference in the variance (F=1.19), while the means were significantly different (T=2.07). Visual inspection of the frequency data 37 .