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r position as chief predator. A depressed plankton base, stable or declining Utah chub population, and competition for prey with lake trout result in less favorable conditions for brown trout than those found in the 1960-1970's. The lake trout has, without question, become the dominant predator in the reservoir. However, lake trout are not able to withstand the warm water and poor oxygen conditions existing in the Inflow Area during the summer months. Brown trout are more tolerant of the Inflow conditions and significantly contri- bute to the catch in the Inflow Area. During 1982, 27.8 percent of the harvest in the Inflow Area consisted of brown trout, while lake trout made up 18.4 per- cent of the total harvest. If brown trout will continue to tolerate the rigid environmental conditions of the Inflow Area where there is an abundance of forage during the summer months, brown trout will continue to be a part of the Inflow fishery. A trophy fishery for lake trout developed in 1977 and has become an integral part of the Flaming Gorge fishery. The fishery is maintained by natural repro- duction, though, two small plants of marked lake trout (Table 2) have been made to study growth rates of the species in the reservoir. Lake trout surpassed the brown trout as the second most dominant fish in the harvest in 1979 (Figure 7). Most lake trout are harvested in the Open Hills Area of the reservoir (Figures 2 and 3), although an important ice fishery for lake trout has developed in the Inflow Area. During 1982, ice fishermen harvested almost as many lake trout as rainbow trout. Lake trout are comparatively slow growing, long-lived fish which mature at 5 to 6 years of age, although some mature as early as 4 (McAfee 1966). Lake trout are reported to be easy to harvest by fishermen when they are located in deep water. Conventional trolling gear produces poor fishing results during the summer months when lake trout are confined to the deep, cooler, well- oxygenated waters of the reservoir.. Therefore, the trophy lake trout fishery has developed into a specialized fishery where specific gear is needed to locate fish and fish deep waters. Boat fishermen account for most of the harvest of lake trout in Flaming Gorge (Figures 2 and 3). The harvest of lake trout increased dramatically from 1975 to 1979 (Table 19) when 10,435 fish were har- vested. In 1980, the lake trout harvest remained essentially the same at 10,404 fish. The lake trout harvest estimate for 1981 was 7,831 fish. However, this estimate was based on the 1978 pressure estimate which showed there to be more fishing pressure in the Canyon than in the Open Hills. The 1982 creel survey revealed that there had been a shift in fishing pressure from the Canyon to the Open Hills Area (Table 13). Schmidt et al. (1982b) noted that if a shift in fishing' pressure did occur, the actual harvest of lake trout in 1981 would be higher than originally esti- mated. Undoubtedly, the harvest of lake trout was higher and would be somewhere between the 1980 and 1982 estimates. In fact, most of the shift in fishing pressure seen in Table 13 can be attributed to the fishing effort expended for lake trout. The 1982 harvest estimate for lake trout was 8,997 fish down slightly from the 1980 estimate. Harvest regulations for lake trout have changed through the study period. In 1978, a two fish per day lake trout limit was established on Flaming Gorge. Then in 1982, the creel limit was modified so that only one fish of the eight fish possession limit could exceed 20 inches. The two fish lake trout limit was retained. The new regulation essentially limits the catch of trophy lake trout to one fish per day. What effect the new regula- tion had on the total harvest is unknown. Average lengths of lake trout have -50-