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<br />. <br /> <br />Similar patterns for bead and marked larvae captures were observed at the sampling site 8 <br /> <br />km downstream of the release location. The first marked larvae arrived at the site approximately <br /> <br />197 minutes after release (Figure 8); the peak in abundance of marked larvae occurred within the <br /> <br />next 60 minutes. Marked larvae were present in samples for only about an hr after they first <br /> <br />appeared. The first beads collected at the site also arrived at a maximum of 197 minutes after <br /> <br />release; peak bead abundance occurred within the next 60 minutes but beads were detected for <br /> <br /> <br />nearly four hr after the first beads were detected at this site. Nearly all beads (n = 1,295,99.7%) <br /> <br /> <br />and all marked larvae (n = 65) were collected on the right bank. <br /> <br /> <br />Substantial numbers of wild (unmarked) razorback sucker larvae (n = 232) were also <br /> <br />collected in the samples, but their distribution differed from that of TC marked, hatchery- <br /> <br />produced larvae. Forty-four wild razorback sucker larvae (19%) were captured at the upstream <br /> <br />1.6 km site; 43 were captured on the right river bank but only one was captured near the left river <br /> <br />bank supporting the notion that particles released at the bar tend to remain on river right. About <br /> <br />81 % of wild larvae (n = 188) were collected at the site 8 km downstream of the release site; 61 % <br /> <br />of those (n = 144) were collected on the left side ofthe river and 39% (n = 44) were collected on <br /> <br />the right side ofthe river. Wild razorback sucker larvae were present for the duration of the <br /> <br />sampling period, about 4.5 hr. <br />From this 2004 effort, we learned that the marking technique was valid and that larvae <br /> <br />from a relatively small batch of fish could be detected in reasonable numbers up to 8 km <br /> <br />downstream. Minimum transport rate at the site 1.6 km downstream of the release point was <br /> <br />about 0.8 m/sec. This is consistent with the transport rate of 0.78 m/sec estimated for larvae <br /> <br />captured at the site 8 km downstream from the release point. Fish densities, based on capture <br /> <br />rates, declined in a downstream direction, but substantial numbers of larvae were captured 8 km <br /> <br />. <br /> <br />. <br /> <br />. <br /> <br />. <br /> <br />. <br /> <br />. <br /> <br />. <br /> <br />. <br /> <br />. <br /> <br />33 <br /> <br />. <br />