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SorinQ ElectrofishinQ Two rare Colorado River fishes, 1 adult Colorado squawfish and 1 razorback sucker, were collected in the San Juan River during spring standardized electro- fishing efforts (Tables 1 and 2). The Colorado squawfish was collected at RMI 130.2 on 23 April, while the razorback sucker was collected at RMI 91.0 on 25 April. Three electrofishing runs were made through each of the 1-mi segments and 5-mi reaches. A total of 29.44 hrs was spent electrofishing between Four- Corners (RMI 136.2) and Sand Island (RMI 87.0); 7.17 hrs of the total effort was spent in the 1-mi segments. Carp, channel catfish, bluehead suckers and flannelmouth suckers were the only species collected in the 1-mi segments where all fish were to be counted (Table 2). Flannelmouth sucker was the most prevalent species encountered (N = 1,507) comprising 79% of total catch, while channel catfish was the least prevalent of these four species (N = 64) comprising 3% of total catch (Table 3). Striped bass and speckled dace were not encountered during the spring standardized electrofishing in 1988. The abundance (fish/mile) of channel catfish and carp remained relatively the same in the river reaches (river reaches 18-27, RMI 87-136.2) that were electrofished in the spring 1987 and the spring 1988 (Figures 5 and 6, Table 3). Conversely, the abundance of combi ned suckers (i. e., b 1 uehead, fl anne 1 mouth, hybrid and unidentified) varied considerably between the two periods, especially in the upper five river reaches (Figure 7 and Table 3). Comparisons were not possible between individual sucker species as a result of differential netting effort of suckers between the two years. A greater effort was made to net all suckers and identify to species in 1988 rather than classify them as unidentified. A total of 1.25 hrs of additional target sampling was conducted in the ri ver near the site in wh i ch the razorback sucker was co 11 ected and in an adjacent irrigation pond were razorback suckers were collected in 1976 (BLM 1981); 0.85 hrs of the total target effort was in the river and 0.40 hrs in the irrigation pond. No rare Colorado River fishes were collected in either location. Carp, black bullheads and largemouth bass were the only species collected in the irrigation pond (Table 2). Piute Farms Netting Ten adult razorback suckers were collected near the boat 1 aunch at Pi ute Farms, Utah; half of which were in reproductively ripe condition (Table 4 and Appendix A). Trammel nets were set for a total of 342 net-hours. Lengths, weights, sex and tag numbers of captured rare fishes from both years are compiled in Appendix B. Six of the 10 razorback suckers were recaptures from the netting efforts in 1987. These fish were collected in the same area as in 1987. Carp, channel catfish, black crappie, bluegill, flannelmouth sucker, largemouth bass, smallmouth bass and walleye were also collected near Piute Farms in 1988 (Tables 2 and 5). A comparison of catch rates (fish/net-hour) for population trend information between the two years would be meaningless because of differential effort. Netting effort in 1988 concentrated just on those sites where razorback suckers were collected the previous year, rather than covering a cross section of habitats in and around the mouth of the San Juan River. Based on the ratio 12