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Findings from this study have provided a somewhat confused picture on razorback migration and movements. In the main upper Colorado, almost no movement has been documented on razorback suckers. Most razorbacks captured in this area were in man-made gravel pits and four recaptures out of five were in the same gravel pit area. However, some movements into and out of these gravel pits have been documented. In the Green River, a razorback was recaptured, after five years, 125 mi from the tagging site. Also in the Green River, one razorback was radiotagged near the confluence of the White ,and Duchesne Rivers. This fish remained very near this area all summer with only very short movements observed. Spawning concentrations have been observed in the spring both in this study and in previous work. One area of concentration was noted in the Green River the mouth of Ashley Creek. Another area that has been observed in past studies is an area in the Green River near the mouth of the White River. Therefore, some limited movement to these areas of spawning concentration must occur. Generally, we concluded that razorback suckers do not make long migrations. Locally, the species concentrated at spawning time in very defined areas of the river to spawn. They also moved into backwater gravel pits at high waters, conceivably for the purpose of spawning. As the water level droped in the gravel pit areas, razorbacks returned to the main rivers. Habitat Selection Few razorback suckers were collected in the standardized sampling program making any extrapolation from the data associated with captures potentially biased. Those few fish that were collected during the systematic sampling generally exhibited a preference for negligible currrent, moderate depths and a silt substrate. Eighty-two percent of the razorback suckers collected from the Colorado River were from gravel pits and backwaters. Those fish in- habiting the Green River did not exhibit this affinity to still waters but were usually associated with deep shorelines and main channel areas of low velocitq. Late spring congregations of this species suggested selection of a specific habitat composite for spawning. Actual spawning was not observed nor byproducts collected; however, it was felt that the con- gregations of razorbacks in the vicinity of~Ashley Creek, the Walter Walker Wildlife Management Area gravel pit and Clifton Fond gravel pit represented some facet of spawning. These areas lacked the clean, loose rubble and gravel suggested as important by McAda and Wydoski (1980) and Ulmer (1981) though some upwelling of water has been detected along one bank of the Walter Walker Management Area gravel pit. Since no recruitment was ever observed during these studies, definitive conclusions relative to spawning habitat cannot be drawn, or if, in fact, these areas represented spawning sites.