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Trends in flannehnouth and bluehead sucker catch rates differ greatly (see Appendix Figure 3 ). Since 1989, flannelmouth suckers were collected at each trend site with only two exceptions: RM 175.3 in 1991 and again in 1996. Trends in the flannehnouth sucker catch rate has followed a similaz same pattern to that of the chubs, with relatively high catch rates recorded in 1989 followed by a general decline throughout the canyon through the 1994 sampling trip. In 1995, CPE increased dramatically at all sites with the greatest site CPE recorded at RM 184.8. Electrofishing has also produced large catches since 1994, with 122 individuals captured that year and 175 collected in 1996. A length frequency analysis for flannehnouth suckers (Appendix Figure 5) indicates poor recruitment of juvenile flannehnouth sucker through 1993. Beginning in 1994 and continuing through 1996 the population, as defined by length frequency analysis, looked healthier. Flannehnouth sucker reproduction, as indexed by YOY catch rates, was remarkably consistent from 1992 through 1995 and appeared to increase in 1996. However, YOY sampling in this study (PART B) targetted Gila spp. first and squawfish second;- airy information gathered on native suckers is qualitative at best. The companion study (PART A) will provide more definitive analysis of native and non-native reproductive success. Bluehead snickers were more spottily distn'buted; absent from 25% of the trend site samples over since 1992. Bluehead suckers were -more common in the upper reaches of Deso/Gray canyons (Appendix Figure 3) . Average annual net catch rates were lowest in 1990 (0.009) and greatest in i 994 (0.08). As with-the flannehnouth suckers, blueheads became relatively abundant in electrofishing samples in 1994.. Bluehead YOY catch rates declined steadily from -1992 through 1996 as did the native speckled dace. Channel catfish were the most abundant species collected from main channel habitats with nets and electrofishing every year of study. Throughout the course of six years offish community monitoring channel catfish have been nearly twice as abundant as Gila spp. As with chubs and flannelmouth suckers, channel catfish average annual net catch rates were greatest in 1989 (0.918) and were lowest in 1994 (0.149)(see Appendix Figure 3). The highest channel catfish catch rate (1.21) was recorded in 1990 at Cedar Ridge (RM 184.4). A length frequency analysis reveals a dynamic population with Age 1 catfish (TL range 100-200 mm) present every year with the exception of 1994 (Appendix Figure 6). The 1993 cohort of YOY catfish apparently did not overwinter well evidenced in the 1994 histogram where catfish between 100mm and 200mm were relatively scarce for the first time in this study. DRAFT - ~ ~ , . 15 - _. ~ ~.~~~~: