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bladder problems. Four fish were placed in each live car and lowered to a depth of 35 feet. After 5.5 hours, the live cars were hauled to the surface. All fish were in extremely good condition. They were active, brightly colored and showed no signs of stress. All the fish swam away normally after their release. The fish used in the experiment ranged in length from 19.6 to 23.3 inches and in weight from 2.4 to 4.5 pounds. Tags from two of the eight lake trout used in the experiment have been returned. During the spring of 1985, three lake trout were placed in a live car overnight. Conditions of these fish were similar to fish described in the 1982 experiment. All three fish were in excellent condition after being hauled to the swface from a depth of 65 feet. Table 2 summarized the condition of 1985 tagged lake trout at their time of release and how they returned to the creel through February 14, 1986. The condition of tagged lake trout was categorized upon their release as excellent, good, fair and poor, based upon their response and general condition when they were released. Of the 400 lake trout released, 64% were in excellent condition, 25% in good condition, 7% in fair condition and 4% in poor condition. No fish were released that were judged to be fatally injured. Table 2 shows that lake trout returned at almost identical rates to the percent tagged in each category. Returns of the fish in the fair and poor categories are encouraging and add validity to the study. A population estimate was calculated from the 1982 harvest data and tag return data using a modified Peterson method. The harvest of lake trout in 1982 was 8,997 and based upon a return of 21 tagged lake trout out of a possible 212. The population of catchable lake trout was 87,117 :I:. 17,225 at the 95% confidence interval. Angler exploitation, based upon the harvest and population estimate in 1982 was 10.4%, while angler exploitation from the 1982 tagging study was 9.9%. DISCUSSION The number of lake trout tagged during the fall of 1981 and spring of 1982 was disappointing. It was estimated that at least 400 tagged fish were needed to provide adequate returns. Valuable know lege concerning the time of year tagging should occur, lake trout habitat, netting and tagging procedures was gained. Nets with the mesh sizes 2.0, 2.5 and 3.0 inches caught most of the lake trout. The 4.0 inch mesh nets were not used in 1985. The Floy FD68B plastic anchor tags were abandoned in favor of the Ploy cinch-up tag to lower tag loss and add confidence to the study. The exploitation study is based upon the voluntary return of the $5.00 reward tags. The $5.00 reward was used as an incentive for anglers to return all tags from tagged fish which were caught. How many tagged lake trout have been caught and the tags not returned is a question we cannot answer at this time. Weare now asking all anglers contacted during creel census interviews if they have or know someone who has caught a tagged lake trout on Flaming Gorge during creel interviews. This has been responsible for the return of at least a dozen tags which may not otherwise have been returned. The Wyoming Game and Fish Department is working on a non-response correction factor which can be applied to this study. We hope to have an answer to this question by the end of 1986. It may be that a larger reward needs to be offered in order to get most of the tags returned. The literature is rich with examples of tagging studies which have failed because of poor angler response concerning the return of tags. Green et al. (1983) estimated tag return rates directly by surrepititiously implanting reward tags into fish which had already been caught during creel surveys. 22