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. After sorting through drift samples and counting beads and larvae captured in the main channel, these numbers were used to determine patterns of drift downstream from release sites. Location of capture (left bank, right bank, or main channel) was noted, as was timing of capture (relative to release), and numbers of beads and larvae captured within the breaches. The few fish captured were identified and TC marked otoliths from early life stages of razorback sucker were verified. However, we make only passing mention of the fish data collected in 2005 and 2006 because preservation issues, especially in 2005, limited the number of fish recovered from samples. Even though more fish were preserved and recovered from 2006 samples, we could not establish which samples were well preserved and which were not, which made it difficult to know if fish presence or abundance data were reliable. In addition, it became clear upon reviewing sampling data that the GO Model 2030R flow meters did not accurately measure velocities at lower flows in drift net samples. Without backup flow velocity information such as Marsh-McBirney flow measurements in net mouths, we had a number of gaps in data used to estimate the amount of flow sampled by nets. Because of this, results from 2005 were used to calculate only the percent of released beads captured in breach samples as well as to estimate the percent of flow entrained at various sites and at various river stage levels. This data portrays the patterns of bead and flow entrainment over different flow levels but not entrainment rates or densities of beads (e.g., beads per cubic meter of water entrained), which would allow extrapolation of entrainment to the entire breach over the entire sampling period. Because we were unable to extrapolate total bead entrainment, the best measure of entrainment effectiveness then became calculating the percentage of beads entrained into the breach over the different flows. In 2005, this value was calculated using the total number of beads captured in breach samples divided by the total number of beads captured in all . . . . . . . . . 25 .