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0 14 were equally dominant at all three intensive sites (Figure 2). No Colorado squawfish were collected from spring-intensive samples; however, six northern pike were collected at Lilly Park. Intervening sampling occurred in eight backwaters from RMI 45.4 to 106.8. This resulted in capture of 30 squawfish and 32 pike (Table 5). Four of the squawfish mentioned above were observed but not captured in Morgan Gulch at RMI 103.4. These fish probably escaped into the river channel. To increase success in sampling backwater areas the confluence of each backwater was blocked with a trammel net prior to electro-shocking. This technique proved effective in capturing fish that would have otherwise avoided capture by 0 fleeing to the river channel. In most backwater samples, equal numbers of Colorado squawfish and northern pike were collected except at Morgan Gulch (RMI 103.4) 111 squawfish (plus 4 observed) and 3 pike] and Lay Creek (12 pike and no squawfish). Lay Creek is a perennial stream that maintains a fairly constant, clear flow and often remains clear up to its confluence with the Yampa. It is also well 0 vegetated and relatively shallow. By contrast, Morgan Gulch is incised along its banks and is more erratic and turbid, flowing only during locally wet periods or flash floods. 0 As spring runoff flows increase, many fish species, including squawfish and pike, seem to utilize backwater habitats as refuge. Water temperature can be several degrees higher in backwaters than in the river, thus providing 0 better conditions for growth or pre-spawning conditioning. Conductivity is also higher, especially in tributary stream backwaters. For these (and probably other) reasons, backwaters provide excellent habitat for large 9 picivorous fishes during spring runoff. Our ability to catch fish in these areas may also reflect greater efficiency of the gear. Electrofishing is 10