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less than that of radio-tagged pikeminnow in 1996 and 1997. Contact duration was only 51-142 days. Maximum displacement was predominantly downstream (mean=30.9 miles); mean upstream displacement was only 5 miles. Final displacement from the release point was also entirely downstream (mean=26.7 miles; Appendix Table K.3 ). 1999-Tagged Fish Capture and Release. Only Colorado pikeminnow that were captured in the fish trap were implanted with radio transmitters in 1999. Four of the five Colorado pikeminnow (mean TL=561; range=1,150-1,692) were implanted with a smaller (10-gram) LOTEK° transmitter between 5 August and 9 September. Following radio transmitter implantation, these pikeminnow were all released immediately upstream of the Redlands passageway. Movement and Dispersal. In 1999, two of the four pikeminnow radiotagged (Codes 71 and 73) and released upstream of the diversion dam subsequently passed downstream over the dam. One of these pikeminnow (Code 71) spent 26 days upstream of the dam whereas the other fish (Code 73) was located by boat 19 miles downstream in the Colorado River near Fruita, Colorado (RM 156.5), in mid- February 2000. It was last contacted 0.1-mile upstream on 28 June. Another fish (Code 72) provided the most movement information of the four pikeminnow radiotagged in 1999. Following its release upstream of the Redlands Dam, it was located upstream about 5-1/2 months later at RM 6.8 on 29 February 2000. This same fish then moved downstream in the Gunnison River to RM 3.4, immediately upstream of the Redlands Diversion Dam, on 23 April. It remained there until 27 May. It moved upstream again in the Gunnison River and was contacted at Whitewater at RM 15.3 on 13, 14, and 15 June. This was the farthest upstream movement documented by a Colorado pikeminnow that ascended the passageway, was radiotagged, and released immediately upstream of the Redlands Dam. It then moved downstream and was last contacted on 22 July at RM 3.4, immediately upstream of the Redlands Diversion Dam. The fourth pikeminnow (Code 74) was never contacted following its release (Appendix; Table K.4.). Pikeminnow Spawning Site Identification In the Upper Colorado and Gunnison rivers, the onset of spawning and the duration of the spawning period for Colorado pikeminnow varies among years. The onset for mature pikeminnow to migrate and spawn is highly influenced by the magnitude and duration of the runoff and when water temperatures begin to rise following runoff. Spawning has been documented to start as early as late-June 43