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OC) t.". r- ~iller (1995) followed five radiotagged squawfish in 1994 and found similar habitat use and ::movement patterns to those observed in 1993. During prespawning periods (early June), two of the five fish used eddies (mouth of Mancos River) exclusively, one used run habitat exclusively, and two used slackwater habitat most of the time. During late June the fish started moving more between eddy, run, and slackwater habitats, using runs about 60 percent of the time, but eddies and slackwater habitats were still used about 40 percent of the time. As spawning approached in early July, three of the fish moved to the spawning areas observed in 1993, RM 131 to RM 132. One fish moved downstream to the spawning area, and two moved upstream to reach this area. Spawning activities were observed over cobble bar type habitats in close proximity to, but in different locations from, the spawning activity noted in 1993. During the time spent in the spawning area, the three fish used run habitat about 60 percent of the time and eddy and slackwater areas about 35 percent of the time. These habitats were adjacent to the fast, chute-type habitats where actual spawning likely occurred and were probably used for resting and feeding during the spawning period. Spawning chutes are characterized by fast water velocity and clean, loose cobble with a median diameter of 60-80 millimeters (mm). One site (RM 131.1) had overhanging vegetation providing shade and cover (Miller 1995). Following spawning, the three fish dispersed upstream and downstream from the area. Run habitat was used the most in the late summer and fall periods, with eddies and slackwater habitats still an important part of the habitats used. During the spawning period, Miller (1995) noted that two of the five radiotagged fish did not move to the suspected spawning areas. One fish stayed in or near the mouth of the Mancos River (RM" :' , 122) for the entire period, and the other fish was not located during the spawning period but was ' found upstream (RM 134.4) in mid-July when spawning appeared to be over. To reach this upstream ' location it had to swim through the suspected spawning area. Miller (1995) also noted that one fish that tended to spend its time in eddy habitats was a female. Miller (1995) also studied habitat use of three adult squawfish during February 1994. Runs were used about 90 percent of the time, with an eddy being'used for the remaining 10 percent of the time. The fish were active, especially during midday, suggestingactive feeding. These observations differ from those of Valdez and Masslich(1989) about the Green River in that the San Juan Squawfish were much more active. However, this may be due to warmer temperatures and lack of an ice cover, since the winter of 1993-94 was a relatively warm winter. Several studies have looked at habitat use by young squawfish in the San Juan River. A variety of low velocity habitats have been sampled by several researchers (Platania 1990; Buntjer et al. 1993, 1994; Lashmett 1993, 1994; Archer et al. 1995, 1996) resulting in the capture of 18 YOY in 1987, 1 in 1988, 1 in 1990, 1 in 1992, 11 in 1993, 7 in 1994, and 0 in 1995. Although a variety of slow water habitats were sampled in these studies, including backwaters, embayments, secondary channels, and eddies, all of the young squawfish were caught in backwaters. This is similar to other Upper Basin studies which showed that young squawfish strongly prefer backwater habitats. Summary Studies conducted under the SJRRIP showed that Colorado squawfish habitat use in the San Juan River appears to be generally similar to those in other Upper Basin river systems. Adults use low San Juan River Recovery Implementation Program Summary Report 24 17 January 1997 PR-576-2