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. . downstream. Because a large portion of fish may occur in the middle of the channel, we determined that sampling should also occur there in future efforts to be able to detect their presence. Also, releases larger than those in this test may allow for detections much further downstream. Significantly, average drift rates of beads and larvae were similar (0.62 m/sec vs. 0.44 m/sec, respectively, for the 1.6 km site; 0.37 m/sec vs. 0.32 m/sec, respectively, for the 8 km site). Total capture rates were also similar: 0.3% vs. 0.36% respectively for percent of released materials captured. Although average transport rates were similar, larvae always arrived more quickly than beads (likely a result of the larvae's ability to actively swim). This indicated that beads may be a suitable surrogate for fish larvae, should larvae not be available for all test releases in the future. Cross-channel distribution of beads and marked larvae suggested little mixing over the 8 km distance downstream of the release site because nearly all beads and marked larvae were captured on the right side of the river. This may be explained at the 8 km site by the sharp left turn in the river a short distance downstream from Razorback Bar that likely maintained most drifting particles down the right side of the channel with the thalweg. However, our ability to infer patterns of cross channel distribution of drift material in 2004 is limited due to a small sample size (only one release this year) and uncertainty surrounding the exact release points. Additional releases and additional sampling sites further downstream than 8 km from release sites are needed to better assess mixing across the channel. The few captures of marked larvae adjacent to breaches at the Thunder Ranch wetland complex suggested that, at 2004 flow levels and channel dynamics, few larvae from Razorback Bar would be available for entrainment, even if the breaches had connected to the main channel at these flow levels. Flow dynamics and entrainment rates of additional wild-produced larvae in . . . . . . . . 34 .