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19 <br />of strata to be sampled; but instead used a sequential sampling design <br />with a random start. Utilizing a table of random digits, one stratum <br />was selected as the starting point with the sampling series progressing <br />sequentially downstream to the last strata, shifting back to the uppermost <br />stratum to complete the series. <br />Within each stratum a sample site was selected according to a completely <br />random sampling design. Each stratum was divided into river-mile stations. <br />A table of random digits was consulted and the first numbers encountered <br />in the table that appeared in the section were chosen in the sample <br />1 <br />station. To permit replication and to extend the boundaries of each <br />sample, each station consists of two 0.5 mile reaches; one extending <br />downstream from the selected river mile starting point, the other five- <br />miles downstream (Figure 2). Intensive sampling began in the uppermost <br />0.5 mile section continuing for 24 hours. The second day, the intervening <br />4.5 mile section was surveyed by el;ectrofishing starting at the lower <br />S <br />boundary of the previous sample sits and continuing downstream to the <br />upstream point of the second 0.5 intensive section. From this point, <br />the second 0.5 mile section was intensively sampled for 24 hours. <br />Generally, sampling was discontinued after the second intensively sampled <br />reach was completed and the field crew usually returned to home station.