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. . Beads released at Razorback Bar and Escalante Bar in 2005 were collected in all downstream breaches and as far downstream as L-7, 85 km downstream from the release. Some larvae were also captured in the L- 7 near and far shore nets at each sampling occasion. . Wetlands in close proximity to larvae production areas will only see high levels of entrainment if they are located on the same side of the river as the production areas. . Drift particle density declines downstream, based on recaptures of released beads and marked larvae because beads disperse longitudinally and are retained laterally. This suggests that wetlands closer to production areas can potentially contribute greater numbers of razorback sucker to the population. However, downstream bead densities and fish captures were substantial and suggest that sufficient numbers of razorback sucker larvae may drift from upstream production areas to populate flood plain wetlands well downstream. Ifwetlands are to be enhanced or improved, candidate wetlands should be present in a mosaic of locations up and down the river and on each side of the river. . Entrainment rates of beads, water, and presumably fish decline dramatically or cease when single breach wetlands (e.g., Stewart Lake when outlet is closed, Stirrup, L-7) are filled. These same breaches would theoretically release water and some drift material as river flows recede, as was observed at L-7 in 2005. . Bead entrainment is higher in flow through wetlands and increases as river stage and flows increase. Entrainment of beads, water, and presumably fish larvae would be highest when the greatest volumes of river flow are entrained. We suspect this relationship would remain true for Green River flow at levels higher than those we observed. . Bead and flow entrainment rates in flow-through wetlands are similar on the ascending and descending limbs of the hydrograph. . . . . . . . . . 55 .