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<br /> <br />and around the Mancos River confluence (RM 122.6) during pre-spawn periods, <br />May and early June. During the estimated 1993 spawning period, 50% of all <br />contacts made with Colorado squawfish occurred in the Mixer (RM 133.4-129.8), <br />a decline from previous years. Colorado squawfish in the San Juan River from <br />1991-1993 show a trend of making only localized movements. All radio contacts <br />in 1993, except those made with the fish captured in Reach VI, occurred <br />between RM 142.0 and 117.0. The Colorado squawfish captured in Reach VI has <br />not moved more than a mile from its capture location in October 1993. Over <br />the last three years, the highest percentage of ground contacts (45.8%) were <br />made with Colorado squawfish using run habitat. For 1991-1993, mean maximum <br />displacement (8.41 miles) and mean final displacement (4.46 miles) were very <br />close to that of Colorado squawfish in the "IS-mile reach" of the Colorado <br />River near Grand Junction, Colorado. Mean total longitudinal movement (9.86 <br />miles) also indicates only localized movements. All of the above information <br />suggests that Reach III is important to the native fish fauna (adult and <br />juvenile life stages) of the San Juan River. <br />Information to date is insufficient to assess the impacts of existing <br />instream water diversion structures on rare fish movement. <br /> <br />ii <br /> <br />J <br />