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subsequently implanted with transmitters for radio tracking on September ll, 1987. It was interesting to note that two of these Colorado squawfish, 641 and 702 rom total length, and the northern pike, 844 rom total length, were captured in the above order on virtually successive casts of a lure to the same spot at the head of the pool/eddy interface. Approximately 2 hours later, another Colorado squawfish, 833 mm total length was captured by angling 10 m away at the tail end of the same interface. Comparison of tracking locations of the two northern pike and four eolorado squawfish bearing transmitters (from Wick and Hawkins 1989) in the Lilly Park reach from September through early June demonstrated the two species crossed paths multiple times, suggesting numerous encounters between the two species were possible. Habitat use during the fall and winter by the northern pike varied between pool, shoreline, eddy, and runs in order of decreasing frequency (Table 5). Habitat use by the Colorado squawfish in this reach during the fall and winter centered primarily on pools with some lesser use of runs, eddys, shorelines and embayments (Wick and Hawkins 1989). In the Maybell reach, seven northern pike and six Colorado squawfish were radio tracked at various periods during 1986 through 1988. In one instance at the major pool at RM 80.8, a 738 rom northern pike used for transmitter implantation was captured by angling at the edge of a large bed of aquatic vegetation bordering the deepest portion of the pool. Within the same afternoon, a 558 rom eolorado squawfish was also captured by angling but this fish was taken near the foot of the same pool where it breaks into riffle habitat. Subsequent sampling of this pool by angling has resulted in the capture of Colorado squawfish at both the head and tail of this pool. Comparisons of tracking locations between the two species in this reach indicated a similar coexistence within a relatively small reach (RM 80.6- 81.4). Both northern pike and Colorado squawfish demonstrated a-strong "attraction" for the pools, embayments, and backwaters in this reach during the fall and winter seasons, though Colorado squawfish also were frequency found in run habitat (Wick and Hawkins 1989). Both species appeared active within these low velocity habitats during the fall and winter seasons and pike would move between adjacent pools at RM 80.8 and 81.1. 30