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Length-Frequency A The length-frequency histograms for Westwater Canyon roundtail chub indicated no clear separation of size classes for 1998 and 1999 (Figure 9). In 2000, there was a bimodal distribution with the size classes being 170-190 mm and 240-350 mm. The largest roundtail chub caught in each year was 390 mm in 1998, 380 mm in 1999, and 390 mm in 2000 (Figure 9). ~ Growth Mean annual growth rates of Westwater Canyon roundtail chub were compared with respect to the bimodal distribution of size classes determined from the 2000 length-frequency histogram. To allow comparison between roundtail chub and humpback chub, mean annual growth rates were also examined with respect to the bimodal distribution of humpback chub exhibited in the 1998 and 1999 length-frequency analyses (Figure 3). Mean annual growth rates were 45.67 ~ 8.51 mm for roundtail chub less than 210 mm and 16.10 t 1.70 mm for roundtail chub greater than 210 mm. Roundtail chub less than 28S mm had a mean annual growth rate of 22.56 ~ 2.26 mm and roundtail chub greater than 28S mm had a mean annual growth rates of 7.30 ~ 1.60 mm. Analysis of the larger data . sets from recaptures in 1999 and 2000 indicate a pattern of growth that may shift slightly between years (Figure 10). Movement Movement of roundtail chub as determined from long-term recaptures (individuals tagged in ~' previous years) varied from 1998 to 2000. However, through the entire study, 89% exhibited no net movement. There were 291ong-term recaptures of roundtail chub in 1998. These individuals had been tagged in the period 1-6 years prior to 1998.Of the 29 recaptures, 24 (82.8%) were recaptured in the same location, three had moved from Hades Bar to Cougar Bar, and two had moved from Miners Cabin to Cougar Bar. Only three of these roundtail chub had been captured in 1997. In 1999, there were 341ong-term recaptures of roundtail chub that had been initially captured in the previous 1-7 years. Of those, 33 (97.0%) were recaptured in the same location and one individual had moved from Hades Bar to Cougar Bar. In addition, twenty-two of these 341ong-term recaptures were captured in 1998. Two additional fish were tagged in Black Rocks in September 1999 and subsequently recaptured at Miners Cabin in October 1999. The final year (2000) resulted in the ~ recapture of 46 roundtail chub that had been previously captured in the preceding 1-8 years. Of these 461ong-term roundtail chub recaptures, 41 (87.2%) were recaptured in the same location, two had moved from Hades Bar to Cougar bar, one had moved from Cougar Bar to Miners Cabin, and one had moved from Black Rocks to Miners Cabin (originally tagged in 1999). The 461ong-term recaptures in 2000 resulted in 27 individuals that were captured in 1999 and 13 individuals that were . captured in 1998. Comparison with ISMP The historic (1988-2000) ISMP catch per unit effort for roundtail chub in Westwater Canyon indicates a slight decreasing trend (Figure 11). The slope of this trend does not significantly depart ~ from zero. Mean catch per unit effort between 1988 and 2000 as per ISMP sampling protocol was significantly different between 1990 and 2000 and between 1993 and 2000 (p < O.OS; Kruskal- ~ 8