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Harvest of lake trout increased annually until 1980 when it stabilized at just over 10,000 fish. Harvest in 1981 declined to approximately 8,000 fish and then increased to 9,000 fish in 1982. Table 1 summarizes the harvest of lake trout from Flaming Gorge Reservoir from 1978 through 1982. During this time period, there was an average of 0.26 lake trout (1.6 pounds) harvested per surface acre. McAfee (1966) states that in order to maintain a wild population indefinitely, lake trout populations in most inland Ontario lakes can sustain a yield of slightly less than 0.5 pounds/surface acre. Harvests from Flaming Gorge are over three times the sustained harvest recommended by McAfee (1966) for inland Ontario lakes. Preliminary harvest data from 1984 and 1985 indicate that lake trout harvest has increased slightly and will be the highest number yet recorded. Harvest regulations for lake trout changed from an eight fish/day limit prior to 1978, to a two fish/day limit in 1978. In 1982, the creel limit was modified so only one fish of the total trout daily limit could be 20 inches or larger. Although the limit on lake trout remained at two fish/day, the new regulation essentially limited the catch of trophy lake trout to one fish/day. Daily limits and possession limits are one in the same. During 1981, the Wyoming Game and Fish Department and Utah Division of Wildlife Resources became concerned about the future of the lake trout fishery in Flaming Gorge Reservoir. Publicity about the trophy lake trout fishery resulted in increased fishing pressure directed toward the lake trout. Both management agencies wondered whether the new harvest regulation (one fish 20 inches or greater) would be restricive enough. To adequately analyze the impact of the harvest of lake trout, a tagging study was devised to study movement, assess angler harvest (exploitation), analyze population dynamics and study age and growth in the reservoir. The primary objective of the tagging study is to evaluate the exploitation of lake trout from Flaming Gorge and to design more restrictive harvest regulations, if necessary, to preserve the quality of the fishery. Initially, the tagging study was to be done on a limited basis during fall netting in 1981 and intensively during.the spring of 1982. Preliminary harvest data during 1984 caused increased concern that lake trout exploitation was higher than rates calculated during 1982, and the study was reinitiated during the spring of 1985. Lake trout tagging will also occur during the springs of 1986-1988 to collect sufficient data to analzye exploitation rates and evaluate harvest regulations. METHODS Fish were tagged in October, November and December of 1981 and April and May of 1982 with Floy plastic anchor tags (FD68B) with the inscription "$5 REWARD UTAH FISH AND GAME SLC" and a serial number. The tags were inserted between the interneural spines below the dorsal fm with a Floy tag gun which had a 29 mm needle. In April and May of 1985, Floy plastic cinch-up tags with the inscription "$5 WYO. GAME AND FISH $ CHEYENNE, WY 82002" and a serial number were used. The cinch-up tags were inserted between the last two interneural spines of the dorsal fin with a hollow needle. The tag was then cinched up close to the body so it fit snuggly, but allowed adequate room for growth. Antiseptic was then sprayed on the wound to prevent infection. Utah and Wyoming participated in the lake trout tagging in 1981 an4 1982, while Wyoming tagged all the fish in 1985. Lake trout were captured using sinking monofilament exploratory gill nets. The nets were 200 feet long by 6 feet deep. Three nets had a bar mesh of 2.5 inches. Three other nets had bar mesh sized of 2.0,3.0 and 4.0 inches, respectively. Each of the three reservoir areas was sub-divided into smaller zones arbitrarily so netting effort could be spread over the entire reservoir. Each zone was to receive equal sampling effort so results would accurately reflect exploitation of the entire population and not be biased by returns from heavily or lightly fished zones. Each zone was to be sampled 16