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late-February 2003. However, water temperature data for the same period at Una could not be downloaded in late-February 2003 because ice conditions on the bank precluded retrieval of the cable holding the recorder. At Stateline (RM 134.0) and Cameo (RM 199.8), main channel water temperature of the Colorado River was monitored and recorded by U. S. Geological Survey gages. Daily maximum water temperatures were used at each of these four locations to report the number of days water temperatures between 18 and 23° C were equalled or exceeded during 2000, 2001, and 2002. For Una, the number of days for 2001 and 2002 was estimated by interpolation using maximum daily water temperatures at the Cameo and Rifle recording gages. Statistical Testing A two-tailed, sample t-test (Statistix® soflwaze for Windows) was selected to test differences between size groups offish that moved over the Government Highline Dam and into the canal system versus those fish that remained upstream of the diversion dam during the study. RESULTS AND DISCUSSION The movements of Colorado pikeminnow were described by the yeaz they were radio tagged. The reason for this was, in 2000, domestic-reazed and wild fish were handled and held differently than wild Colorado p~emiimow collected in 2001. Fish Radio Tagged in 2000 Wild Fish The duration of time that radio-tagged fish were contacted varied greatly. Some of the variation could be explained by the guaranteed life expectancy of the radio transmitter used. For the five wild fish, contact was maintained from 5946 days (Table 1). Three of these fish exhibited some upstream movement (meat~5.3 miles; range=0.8-13.7) following release, but were never detected upstream from the stocking point. However, most of the movement of the wild fish was downstream (mean=28.2 miles; range=13.2-35.3). The movement of one fish, Code 134, was particulazly noteworthy. This fish moved downstream about 29 miles from its stocking site and moved into the Government Highline Canal in mid-July (Appendix E). The fish then moved downstream about 1.4 miles in the canal, where its signal was detected by the data 13