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<br />Bo ytail <br />Survival <br />Abundance of bonytail at the termination of the study was estimated to be 952 (95% CI = <br />~ 941-972) in the high-density enclosure, and 368 (95% CI = 364-381) in the low-density <br />enclosure. A total of 898 were harvested from the control enclosure. This equates to 1.3% <br />survival in the high-density enclosure, 1.7% in the low-density enclosure and 17.1 % in the <br />~ control enclosure. The population outside the enclosures was estimated the last week of July to <br />be 11,553 bonytail (95% CI = 9,649-13,915), twelve percent of the bonytail introduced had ', <br />escaped the enclosure. Therefore, survival estimates within enclosures are conservative, as it is <br />likely that fish escaped as larvae through very small holes and would have difficulty reentering <br />the enclosures after they grew. <br />Growth <br />~ Bonytail were sampled on June 22 with a single fyke net per enclosure to measure growth <br />rates. Bonytail were the most numerous fish captured in each net on this date. <br />However, nonnative age-0 fish were observed to be abundant in the enclosures, but the <br />~ mesh size of the fyke nets (0.32 mm) was too large to adequately capture smaller individuals. <br />On this date, no significant difference in mean total length of bonytail was observed between <br />high 47.2 mm (std 5.6 mm), and low-density 46.5 mm (4.9 std mm) enclosures. Samples were ', <br />~ not taken from the control enclosure. <br /> <br /> <br /> <br />Fish were again sampled between July 30-August 13, 2003. Growth rates for fish in I, <br />both enclosures were 0.8 mm/d for the 51 days following stocking. Total length of bonytail <br />harvested from study enclosures was 63.0 mm (std 7.7 mm) in high-density enclosures, 57.4 mm <br />(std 7.0 mm) in low-density enclosures, 51.3 mm (std 5.8 mm) in the control enclosure, and 95.0 <br />mm (std 8.2 mm) from outside the enclosures. <br />13 <br />