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early July. In the Green River, 50% of adult squawfish were collected in shoreline habitats and 38% in eddies. Eighty-two percent of Green River squawfish were captured over rubble/boulder substrate. No adult squawfish were collected in backwaters in either the Green or Yampa rivers and only two individuals were collected over gravel substrate, both in the Yampa River. A total of 52 adult Colorado squawfish were captured during post- runoff in the Yampa River at water depths averaging 3.4 ft (1.0 m) and velocities averaging 1.4 ft/s (0.43 m/s) (Table 17). In the Green River, 9 adults were captured at an average water depth of 4.6 ft (1.4 (m) and average water velocity of 1.03 ft/s 0.30 m/s) during postrunoff. In both the Green and Yampa rivers, average water depth at point of capture was greater during postrunoff than runoff, although average river depth was noticeably greater in both rivers during runoff (refer to Table 4). Habitat created by high water, such as overbank flooding and creation of side channel connections to the main river, may have provided refuge areas aways from currents during high water. For post- runoff these areas would not be present. Including all collections, average water velocities at point of capture were higher during post- runoff than runoff in the Yampa River, but the reverse was true. if only standardized sampling captures are considered. This difference was due to the large number (36) of adult squawfish captured in relatively swift areas during special spawning/radiotelemetry studies in July, the post runoff period. Thus, spawning activity during postrunoff would bias the velocity preference during that period. Mean water depths and velocities for capture localities of adult Colorado squawfish by habitat types in the Green (Figure 11) and the Yampa (Figure 12) rivers indicated similar preferences for these two parameters in similar habitats between the two rivers. Average shore- line and eddy capture depths were slightly greater in the Green, but were approximately equal in pool and main channel habitat in both rivers. Migration and Movement - Information about migration and movement of adult Colorado squawfish was obtained from recaptures of conventionally tagged fish and from radiotelemetry. Movement of young was evaluated by catch records. By 14 May seven Colorado squawfish from the Yampa River and one from the Green river were surgically implanted with radiotransmitters. In late June the radiotagged fish in the Yampa River began moving down- stream from their original points of capture and in early July were 52