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<br />Humpback Chub Monitoring: <br />Gear Type: Entanglement Nets Time Period: September <br />Habitat type: All . <br />River Miles Sampled: Colorado River -- 135.0 to 137.0 or 112.0 to 125.0 <br />All compatible data were combined into a single file for each monitoring program <br />to make data summary and analysis easier. All data collected by different <br />investigators were analyzed separately to allow for comparisons among the <br />different sampling designs. One exception to separate analysis was the post- <br />larval data collected in the lower Colorado River by the Fish and Wildlife <br />Service and the Utah Division of Wildlife Resources from 1983 to 1985. These <br />data were collected jointly and were therefore analyzed jointly. <br />All the examined data exhibited high variability which made data analysis <br />difficult using normal techniques. Therefore all data were transformed before <br />analysis began. Mean CPUE was regressed against variance to determine the <br />appropriate transformation for each data set (Box et al. 1978). The post-larval <br />data had a slope of about 1 which indicated that a log transformation would be <br />correct. The adult data had a slope of about .5 which suggested that a square- <br />root transformation would be correct for these data. Because of the zero catches <br />that occurred in the post-larval data, 1 was added to the CPUE for each sample <br />before the log transformation was done. All calculations were done using the <br />transformed data; however, the numbers were converted back before plotting or <br />reporting in the enclosed tables. To correspond with data collected during <br />previous collections, only data collected from primary backwaters (see ISMP <br />Handbook) in the monitoring program were analyzed. <br />3