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-48- <br />Growth of fish determined from creeled fish may not accurately <br />represent actual growth rates. Catchable fish planted in 1977 <br />increased in size most between stocking and the earliest month of <br />capture, while catchables stocked in 1976 and creeled in 1977 grew <br />most late in the summer. A late summer growth pattern is most likely <br />in the Flaming Gorge tailwaters because the warmest water temperatures <br />occur late in the summer. Also, recently stocked catchables usually <br />require an acclimation period before growing well in the non-hatchery <br />environment. Therefore, the apparent early growth of recently planted <br />catchable trout is most likely erroneous and is more likely a result <br />of fisherman selection. As a result, growth estimates based on creeled <br />fish appear unreliable. <br />Recommendations <br />The use of electro-shocking to collect fish on the Green River <br />should continue, since this approach furnishes the best estimates of <br />fish growth and population composition. An effort should be made to <br />perfect techniques so that this type of gear can be used consistently <br />in an effective and quantitative manner. The clear waters of the <br />Green River necessitate shocking at night, so the shocking techniques <br />devised must take into account adequate safety precautions. In <br />addition to estimating growth and species composition, shocking will <br />be useful for evaluating the success of stocking, comparing various <br />strains or species of trout and assessing changes in growth or abun- <br />dance of fish after modification of the penstock intakes on Flaming <br />Gorge Dam. <br />Marking of fish should continue until clear annuli develop in