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1 1 1 Anderson et al. 1994) with final model goodness-of--fit estimated by the scaled deviance. Abundance of Colorado squawfish larvae in dawn nearshore samples and in samples collected at other times and positions was compared by inspecting the mean and standard error (SE) of catch rates. Position, time, and date effects on age and TL of larvae captured. --Dawn-nearshore- samples may detect only a subset of the age- or length-classes of larvae drifting at other times or locations across the channel. Therefore, differences in age (d) and TL (mm) of Colorado squawfish captured in the 1992 diel and cross-channel sampling were analyzed by least-squares GLM (SAS Proc GLM) which had sampling time, net position, and their interaction as covariates. Differences in age and TL of larvae on 30 June, and 4, 13, 15, 24, and 27 July when large numbers were captured were evaluated by analysis of variance (ANOVA). Age and TL response variables were normally distributed. Means and SE's of ages and lengths of larvae in these analyses were also inspected to determine if statistically significant differences were biologically important. Annual transport abundance.--Previous studies calculated number of larvae/volume of water sampled to obtain a density index for Colorado squawfish abundance. Although this was adequate for comparing densities of larvae from samples collected at different positions in the stream or during times of a single day, comparisons of abundance of larvae produced and transported downstream past the sampling station among years or rivers would be flawed because the percentage of the river sampled by drift nets was inversely correlated with river discharge. Hypothetically, if an identical number of larvae was present in the river at both a high and low discharge, density/sample would be higher at low discharge and lower at high discharge but actual numbers transported past the station would be the same. Therefore, transport abundance was estimated by dividing the number of larvae captured in drift net samples adjusted to an hourly rate (dawn samples only) by the estimated percent of total discharge that was sampled. Discharge for Yampa River transport abundance calculations for a given day were those recorded from a station about 75 RK upstream. Discharge for lower Green River transport abundance calculations were from the gage at Green River, Utah (station # 09315000) the day of sampling. Summing transport abundance values for all sampling days within each year allowed an estimate of the abundance of larvae transported past each station during the sampling period.