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1 <br />1 <br />' several males, would spawn over depressions or swim around the area <br />before dispersing. The spawning act only took a few seconds and, other <br />than orienting with the current was similar to that reported elsewhere. <br />' However, on several occasions spawning groups appeared to seek shelter <br />downstream of large boulders and, while maintaining their position, would <br />roll in mass for several seconds." <br />e <br />Adults. Habitat selection by adult razorback suckers changes seasonally. Tyus <br />' and Karp (1990) detected movements of adult fish into flooded areas in earl s rin , <br />Y P 9 <br />and suggested that flooding of bottomlands during spring runoff was important to adults <br />for feeding and for temperature regulation. The flooding of bottomlands also supplies <br />' allochthonous input to the river, which may subsequent) rovide food for one or more <br />YP <br />t life stages. <br />Radiotelemet showed that adult fish i <br />rY n the Green and Duchesne avers, Utah, <br />selected deeper near-shore runs during the spring, but shifted to relatively shallow <br />' waters of submerged mid-channel sandbars during the summer months. The fish <br />occupied depths ranging from 0.6 to 3.4 m (2.0 to 11.0 ft) over sand or silt substrates <br />' with water veloaties of 0.3 to 0.4 m/s (0.33 to 2.0 ft/s) (Tyus 1987). During summer, <br />1 the fish occupied midchannel sand bars where the water was less than 2 m deep and <br />velocity averaged 0.5 m/s (Tyus 1987). These bars consisted of small, underwater <br />dunes and depressions in which the fish may have been feeding on trapped <br />' allochthonous material (Tyus 1987). In winter, radio-tagged razorback suckers used <br />' 15 <br /> <br />